4.5.1 Factors to consider when selecting flue-gas cleaning systems
4.5.1 選擇煙氣凈化工藝需要考慮的因素
4.5.1.1 General factors
4.5.1.1 總的原則
[54, dechefdebien, 2003]
The following (non-exhaustive) list of general factors requires consideration when selecting flue-gas cleaning (FGC) systems:
如下列表(不限于)是考慮選擇煙氣凈化工藝需要考慮的因素
?type of waste, its composition and variation;
廢棄物類型,構成和種類
?type of combustion process, and its size;
焚燒工藝類型,規(guī)模
?flue-gas flow and temperature;
煙氣流量和溫度
?flue-gas content, including magnitude and rate of composition fluctuations;
煙氣內(nèi)容,包括組分的變化量和變化率;
?target emission limit values;
目標排放限制;(脫除效率)
?restrictions on discharge of aqueous effluents;
對廢水排放的限制要求;
?plume visibility requirements;
對煙羽可視性的要求(是否要脫白)
?land and space availability;
土地和空間的大小
?availability and cost of outlets for residues accumulated/recovered;
回收副產(chǎn)物的可利用性和成本;
?compatibility with any existing process components (existing plants);
與現(xiàn)有工藝設備的可匹配性(現(xiàn)有工廠)
?availability and cost of water and other reagents;
水和其他物料的可獲取性和成本;
?energy supply possibilities (e.g. supply of heat from condensing scrubbers);
是否能對外提供能源輸出(如:濕法冷凝塔的熱量對外輸出)
?availability of subsidies for exported energy;
對外輸出能源是否有補貼;
?tolerable disposal charge for the incoming waste (both market and political factors exist);
入場垃圾補貼費(包括:市場和政治因素)
?reduction of emissions by primary methods;
減少污染物排放使用的主要工藝手段;
?noise;
噪音;
?arrangement of different flue-gas cleaning devices if possible with decreasing flue-gas temperatures from boiler to stack.
規(guī)劃不同的煙氣工藝裝置,盡可能地減少煙囪排煙溫度;(從尾氣中盡可能多地獲取能量)
[ 74, TWG 2004 ]
4.5.1.2 Energy optimization
4.5.1.2 能源優(yōu)化
Some flue-gas treatment techniques can add significantly to the overall energy requirements of the incineration process. It is necessary to consider the additional energy requirements imposed by applying lower ELVs(Emission limit values). The following key observations can be made:
一些煙氣凈化技術可以顯著增加焚燒工藝的能源需求(消耗更多能源)。在有些低排放應用是必須要消耗更多能源的。關鍵點如下:
?Reducing dust emissions including boiler ash (and metals filtered with dust) generally requires additional filtration and increases energy consumption.
減少粉塵排放包括鍋爐灰(以及粉塵中的金屬過濾)通常會需要額外的過濾裝置,從而增加能源消耗。
?Reducing NOX emissions to below 100 mg/Nm3 is most often achieved using SCR – which, due to the catalyst sensitivity to fouling and acid attacks, is generally used as a low-dust system in waste incineration, situated at the clean gas end of the FGC system. It therefore
usually requires some additional energy for flue-gas reheating. Very low SOX levels in the raw flue-gas may allow SCR to be used without reheating (see Section 2.5.5.2.2). The energy required for the additional flue-gas cleaning (to achieve very low emission levels)
will result in a reduction of the amount of energy generated by the incinerator that is available for export, or in the equivalent consumption of externally supplied energy. Although infrequent, high-dust SCR is used in some waste incineration plants.
減少NOx的排放至100mg/Nm3以下,通常使用SCR是比較適宜的。但是催化劑比較敏感容易受到污染和酸腐蝕的影響,其通常在垃圾焚燒中在低塵區(qū)域使用,布置于煙氣凈化系統(tǒng)的尾部。因此,通常需要額外的能源來對煙氣進行再加熱。如果原煙氣中的Sox水平很低則可以允許SCR系統(tǒng)不進行在加熱(詳見2.5.5.2.2章節(jié))。要實現(xiàn)額外的煙氣凈化目的(達到超低排放水平)所需要的能源將會使垃圾焚燒所產(chǎn)生的本來可以對外輸出的能源進一步被消耗,或者消耗外部提供的等量的能源。雖然不常見,但是高塵布置的SCR在某些垃圾焚燒廠中也有使用。
?The boiler exit temperature has a major influence on FGC energy requirements – if it is below the acid dew point, additional energy input will be required to heat the flue-gas.
鍋爐出口溫度是決定煙氣凈化系統(tǒng)能源需求的主要決定因素,為了加熱煙氣使他不低于酸露點就需要消耗額外的能源。
?In general, placing the FGC components so that those requiring the highest operational temperatures precede those that operate at lower temperatures results in a lower overall
FGC energy demand (but this cannot be achieved in all cases, e.g. SCR usually requires
clean gas and is therefore placed after the lower temperature gas cleaning stages, as
implementing high-dust SCR avoids the use of energy to reheat the flue-gas but is challenging to implement).
[ 64, TWG(technical working group) 2003 ] [ 74, TWG 2004 ]
通常來說,在布置煙氣凈化各工藝段時,應當將那些最高運行溫度的工藝段優(yōu)先布置在那些低運行溫度的工藝段上游,這樣可以獲得較低的能源需求(但是這個不可能在任何情況下都能實現(xiàn),如:SCR通常需要布置在干凈煙氣區(qū)域,而導致需要布置在溫度較低的凈煙氣段,布置在高塵段可以避免消耗能源去對煙氣再熱,但容易面臨煙氣中污染物組分對催化劑壽命影響的挑戰(zhàn))
4.5.1.3 Overall optimisation and the ‘whole system’ approach
4.5.1.3 整體優(yōu)化及“全系統(tǒng)”方式
As well as considering the energy aspects (see sections on energy above), there is a benefit to considering the FGC system as a whole unit. This is particularly relevant to the removal of pollutants because the units often interact, providing primary abatement for some pollutants, and having an additional effect on others. Depending on the position in the cleaning sequence, different cleaning efficiency values are obtained. [ 74, TWG 2004 ] Multifunctional devices are common, and include the following:
基于能源因素的考慮(看上述能源章節(jié)),將煙氣凈化系統(tǒng)作為一個整體考慮是非常必要的,因為不同工藝段之間經(jīng)常會相互影響,從而與實現(xiàn)最終的去除污染物的目的密切相關。(Sox高了會影響SCR的催化劑,從而影響壽命。預除塵效率過高會造成酸露點偏高從而影響系統(tǒng)的穩(wěn)定性。HCL如果太低,會導致Sox在150度左右的脫除效率等等,很多密切相關的因素)基于在煙氣凈化系統(tǒng)中的不同位置布置,會獲得不同的去除效率。多用途裝置非常常見,包括如下:(如:布袋有除塵功能,還有二次脫酸功能。)
?If a bag filter (BF) is used downstream of reagent injection, in addition to its dedusting effect, it acts as a complementary reactor. The pressure drop through the fabric material distributes the flue-gas on the adhered cake which contains some deposited reagent and, due to the low velocity of the gases, the residence time is long. A BF can, therefore, contribute to the treatment of acid gases, gaseous metals such as mercury and cadmium, and POPs (persistent organic pollutants) such as PAHs, PCBs, dioxins and furans.
如果布袋除塵器被用于干粉噴射的下游,除了作為一個除塵裝置外,它還將成為一個二次脫酸的反應器。通過濾料纖維的壓降會將煙氣分配到濾餅上與存留的反應劑進行接觸,由于除塵器中的氣體流速較低,會因此獲得一個較長的停留時間。因此,除塵器有助于去除酸性氣體,氣態(tài)金屬類如汞和鎘以及POPs(持續(xù)性有機污染物)如PAHs,PCBs,二噁英和呋喃。
?In addition to acid gas treatment, wet scrubbers can help with capturing some dust and, if the pH is low enough and/or with the use of scrubber reagents, mercury.
除了脫酸功能外,濕法洗滌塔對粉塵捕捉也有一定功效,如果PH值夠低或使用一些洗滌劑還能脫汞。( 在脫硫液中加入Fenton試劑可以促進單質(zhì)汞氧化為二價氧化態(tài)汞,從而被脫硫液吸收,提高WFGD的脫汞效率。Lu和Tan等針對利用Fenton反應促進汞的脫除分別進行了實驗室規(guī)模和中試規(guī)模的試驗,試驗發(fā)現(xiàn),脫硫液中加入Fenton試劑時,實驗室試驗中,當H2O2質(zhì)量分數(shù)為0.02%左右、Fe3+質(zhì)量分數(shù)約為0.01%、pH為1.0~3.0條件下,煙氣中單質(zhì)汞的氧化率可達到75%;而中試試驗中也能達到30%~40%的單質(zhì)汞氧化率。)
? SCR de-NOX has an additional destruction effect on dioxins if designed (sized) accordingly.
SCR脫硝裝置如果設計得當,還有一個額外功能,就是能破壞二噁英的能力。
?Adsorption by activated carbon and lignite coke has an effect on dioxins as well as on mercury and other substances.
[ 64, TWG 2003 ], [54, dechefdebien, 2003]
活性炭和褐煤焦(活性焦)吸附工藝能去除二噁英,汞和其他物質(zhì)。
4.5.1.4 Technique selection for new or existing installations
4.5.1.4 新設備或現(xiàn)有設備的技術選擇
Overall optimisation and the interface between FGC system components (as well as the rest of the incineration process) is important for both new and existing installations. With existing installations, the number of options may be more severely restricted than with new installations. Information regarding inter-process compatibility may be found in the sections that deal with individual FGC techniques.
煙氣凈化系統(tǒng)各工藝段(包括焚燒工藝的其余部分)的整體優(yōu)化和內(nèi)部接口對新上或現(xiàn)有設備來說都是同樣重要的。重視現(xiàn)有的設備比新設設備更重要,有關工藝可以在其他章節(jié)找到。
4.5.2 除塵技術
The application of a system to remove dust from the flue-gas is generally considered essential for all waste incineration plants.
通常來說,垃圾焚燒廠都需要煙氣除塵系統(tǒng)。
This section considers the locating of a dust removal stage before other subsequent FGC stages(i.e. upstream dedusting or pre-dedusting) or after other FGC systems (i.e. downstream dedusting).
本章節(jié)考慮了煙氣凈化系統(tǒng)的前置除塵(上游除塵或預除塵)和后置除塵(下游除塵)。
Upstream dedusting is used in combination with wet processes in order to protect the scrubbers.
上游除塵通常和濕法工藝相結合,為了保護洗滌塔。
Downstream dedusting is generally necessary for dry and semi-wet processes in order to capture at the same time as dust the salts produced by the reaction between acid gases and alkaline reagents. In some cases, double dedusting is applied, in which case the downstream deduster is sometimes called polishing deduster. [7, TWG 2017]
下游除塵通常和半干法(SDA)工藝相結合以同時便捕捉吸收塔中由酸性氣體和堿性脫酸劑生成的副產(chǎn)物和粉塵。在有些應用案例中,會使用雙除塵技術,下游除塵器通常被稱為拋光除塵器。(就像濕法洗滌塔被稱為拋光洗滌塔一樣,用于最后的防守和精細脫酸)
4.5.2.1 Pre-dedusting stage before other flue-gas treatments
4.5.2.1 煙氣凈化系統(tǒng)的預除塵
Description
4.5.2.1.1 說明
This section refers to a dust removal stage located after the pre-dedusting in the boiler, [ 74,TWG 2004 ] but generally before other subsequent FGC stages.
本節(jié)是指鍋爐后段的預除塵階段,通常都布置在整個煙氣凈化系統(tǒng)之前。
Technical description
4.5.2.1.2 技術說明
The following pre-dedusting systems are used for waste incineration:
如下預除塵應用于垃圾焚燒:
?cyclones and multi-cyclones (generally in combination with other FGC components for the efficient capture of the finer dust fractions);
旋風或多管旋風(通常要和其他更高效的除塵工藝相結合<估計后面濕法洗滌是不是可以不再追加布袋或靜電>,歌本山項目是個例外);
?electrostatic precipitators (ESPs);
靜電除塵器;
?bag filters (BFs).
布袋除塵器。
(注:這里未提及陶瓷濾筒)
The individual techniques are described in Section 2.5.3.
單獨的技術在2.5.3章節(jié)描述。
Wet ESPs are not generally applied to pre-dedusting on account of the flue-gas temperatures in the pre-dedusting area. [ 64, TWG 2003 ] In general, they are used for polishing after scrubbing. [ 74, TWG 2004 ]
濕式除塵器通常不作為預除塵使用是因為要考慮到溫度因素。通常,他們布置在洗滌塔之后用于拋光處理。
Achieved environmental benefits
4.5.2.1.3 獲得環(huán)境效益(該技術的優(yōu)勢)
Benefits include the reduction of emissions to the flue-gas stream by reducing the particulate
load on later FGC processes
這個利益包括減少了粉塵進入煙氣凈化系統(tǒng)的下游設備或工藝段。
Separation of the fly ash from the FGC residues allows:
將煙氣凈化系統(tǒng)中的副產(chǎn)物提前分離出來:
? reductions in the quantity of FGC residues produced;
減少了煙氣凈化系統(tǒng)副產(chǎn)物的數(shù)量
? separate treatment of fly ashes for possible recycling uses.
將飛灰單獨提前分離出來,有利于循環(huán)利用(我們在山鷹公安和吉安項目都考慮作飛灰鑒別,以希望減少危廢處理量,降低運行成本。)
Pre-dedusting reduces dust loads on subsequent FGC systems. These may then be reduced in capacity and will experience reduced clogging risks, and hence downstream units may be designed smaller and with some degree of reduced costs.
預除塵減少了下游煙氣凈化系統(tǒng)的粉塵負荷。這些將減少了粉塵量從而減少了系統(tǒng)堵塞的風險。(臨淄項目因為沒有布置預除塵,導致刮板機和灰斗堵塞的運行風險大大增加,這也是業(yè)主商務人員占主導決策地位的一個失敗的案例。)同時,下游設備可以設計的更小以便降低一些成本。
Separate collection of the flue-gas components will not be of any environmental benefit if the separated residues are then remixed afterwards. Consideration of downstream aspects is therefore required to evaluate the possibility of real benefits. [ 64, TWG 2003 ]
在某些情況下,如果最終分離物需要再次混合,那就不必要再設計預除塵。所以,在設計預除塵時,需要考慮下游工藝的實際情況來評估是否需要設計預除塵。
ESPs and cyclones alone may have problems reaching the required dust emission levels. However, they are useful as pre-dedusters and contribute to meeting the lowest emission levels when applied in combination with other techniques.
單靠電除塵和旋風除塵是很難達到排放要求的。但是作為預除塵與其他工藝技術相結合,可以有效達到超低的粉塵排放水平。
Environmental performance and operational data
4.5.2.1.4 排放性能和運行數(shù)據(jù)
[ 2, InfoMil 2002 ] Cyclone collection efficiency increases directly as a function of the dust load, flue-gas flow rate, particle size and density. As the fly ash particles are fine, the density is low and the dust load and flue-gas flow rate change, so the dust removal efficiency of cyclones is limited. Normally, dust concentration values no lower than 200–300 mg/Nm3 can be reached. Multi-cyclones, which are based on the same removal principle, can reach somewhat lower values, but values below 100–150 mg/Nm3 are very difficult to achieve.
旋風除塵器的效率會隨著粉塵入口濃度,煙氣流量,粉塵顆粒的大小和密度的變化而顯著提高。(遺漏翻譯)
[ 2, InfoMil 2002 ] An ESP can reach substantially lower dust concentration values than (multi-) cyclones. Depending on the design and the siting in the flue-gas treatment system (pre- or downstream dedusting), and the number of fields, dust emission concentration values of 15–25 mg/Nm3 can normally be achieved. Achieving values below 5 mg/Nm3 is possible with more fields (two or three) and an increased ESP surface (and hence increased cost and space requirements).
靜電除塵器的除塵效率顯著高于(多管)旋風除塵器。根據(jù)其設計和其所在煙氣凈化系統(tǒng)中的布置位置(上游或下游布置)和設計電場數(shù)量,其粉塵排放可輕松達到15-25mg/Nm3。使用更多的電場(2-3個)和更大的通過面積(會因此增加成本和空間),靜電除塵器也可以低于5mg/Nm3的排放水平。
Bag filters are generally very efficient dust removers. Where bag filters are used, most commonly reagents are also injected (although this is not always the case) to build a pre-coat layer over the bags to protect against corrosion and help filtration (especially for deep filtration). [ 74, TWG 2004 ] The reagents used are commonly hydrated lime and activated carbon. Activated carbon reduces the dioxin and mercury loads passing on to the subsequent flue-gas cleaning stages. For wet systems, this helps to reduce the memory-effect dioxin build-up in the scrubber materials.
布袋過濾方式在除塵方面有非常高的效率。當使用了布袋,通常也會選擇干粉噴射工藝以便形成一層濾餅保護濾袋抵御腐蝕(特別是深層過濾)。通常會使用消石灰和活性炭作為干粉藥劑。活性炭會通過吸附減少下游煙氣設備的二噁英和汞的濃度。對濕法系統(tǒng)來說,這有助于減少洗滌塔填料等材料(我理解是包括填料,各類管道表面等)中的二噁英的累積記憶效應。
Care should be taken concerning the level of ash in the hopper as well as cinder (especially if bag filters are installed directly after the boiler) to prevent risk of fire.
應當注意灰斗和爐渣中灰分水平以防止火災。(特別是直接布置在鍋爐下游的布袋除塵器)
[ 2, InfoMil 2002 ] Cyclones are a relatively simple design without moving parts (except for the transport systems used for the removal of the fly ash from the bottom) and, therefore, can have high availability at relatively low costs. However, the pressure drop of the flue-gas stream is relatively high, resulting in an increased power requirement for the flue-gas fan and therefore in additional energy consumption.
旋風分離器是一種相對簡單的設計,無需移動部件(用于清除底部飛灰的運輸系統(tǒng)除外)。因此,可以以相對較低的成本獲得高可用性。然而,煙氣流的壓降相對較高,導致對引風機的功率要求增加,從而增加了能耗。
[ 2, InfoMil 2002 ] For the proper functioning of an ESP, it is important that the flue-gas stream is evenly distributed over its total surface. The pressure drop of the flue-gas over an ESP is low, reducing energy consumption. However, some pre-dedusting equipment (e.g. ESPs, filters) require electricity for their operation. [ 74, TWG 2004 ].
為了使電除塵正常運作,除塵器內(nèi)流程均勻分布是很重要的。電除塵的壓降很低,可以減少能源消耗。但是一些預除塵設備需要使用電力(如:靜電和布袋)。
Table 4.11: Operational data associated with the use of pre-dedusting systems
Table 4.11: 與使用預除塵相關的運行數(shù)據(jù)
The table below provides a comparison of dust removal techniques (used at the pre- and post- dedusting stages):
下表提供了各種除塵技術的比較(作為預除塵和主要除塵)
Table 4.12: A comparison of dust removal systems
Table 4.12: 除塵系統(tǒng)比較
Cross-media effects
4.5.2.1.5 跨介質(zhì)影響(使用該技術而增加的能源消耗或其他影響)
Energy requirements of different pre-dedusting techniques are evaluated in the table below.
下表評估了不同的預除塵技術對能源消耗的需求。
Table 4.13:Energy requirements associated with the use of various pre-dedusters
Table 4.13: 不同預除塵使用所需要的能源需求
The most significant cross-media effects associated with this technique are:
當這些技術在不同介質(zhì)方面最為顯著的影響是:
?energy consumption due to pressure loss, which is higher with bag filters than for other systems;
布袋壓損所需要的能源消耗高于其他系統(tǒng);
?electricity consumption for ESP operation;
電除塵器的運行電耗
?flue-gas PCDD/F concentrations may increase during their residence time in the ESP, particularly when operated at temperatures between 200 °C to 450 °C.
煙氣中的二噁英和呋喃的濃度可能會因為在靜電除塵器停留的時間而升高,尤其是在200-450度之間運行時。(這是為什么歌本山在濕法洗滌中進行脫除的原因。)
Technical considerations relevant to applicability
4.5.2.1.6 技術適用性的考慮
Pre-dedusting requires space for the additional process unit, which may be a limiting factor for existing plants.
老廠改造可能會因為預除塵需要額外的布置空間而無法實現(xiàn)。
Economics
4.5.2.1.7 經(jīng)濟因素
The key aspects of this technique are:
這項技術的關鍵因素如下:
?increased capital and investment costs – for additional process units;
增加資本和投資成本—用于額外的工藝裝置;
?increased energy costs, particularly for bag filtration;
增加能源消耗,特別是將布袋除塵作為預除塵時;
?possible cost reductions for disposal where outlets are available for segregated fly ash;
當飛灰可以單獨處理時,設置預除塵可以減少處置成本。(如:吉安考慮飛灰鑒別,如最終確定不是危廢,可以減少危廢的處置成本)
?possible increased cost of handling additional residue streams (either for recovery or disposal).
由于預除塵需要額外的飛灰輸送和處理裝置(回收或處置),可能會增加投資成本。
Investment costs for a two-line MSWI with a total capacity of 200 000 t/yr are estimated as[12, Achternbosch, 2002]:
2條線年處理20萬噸的市政垃圾焚燒廠的投資估算如下:(2x300t/d)
?ESP (3-field):EUR 2.2 million;
3電場的靜電預除塵:220萬歐元;
?ESP (2-field): EUR 1.6 million;
2電場的靜電預除塵:160萬歐元;
?bag filter:EUR 2.2 million (not clear if this includes an upstream flue-gas cooler).
布袋除塵:220萬歐元(不確定是否包括上游的煙氣冷卻反應器)
The unit operational costs of a bag filter for pre-dedusting may be higher due to the higher energy use associated with the pressure drop and the reagent injection. However, the bag filter's greater removal capacity for dust and for other pollutants (particularly when used with reagent injection) can result in reduced costs for subsequent components of the FGC system.
布袋除塵作為預除塵的能耗應該是最高的,主要是由于壓降和需要噴入藥劑等因素。但是,布袋除塵的除塵和脫酸具有更好的去除率(特別是和干粉噴射一起使用時),這可以降低煙氣凈化系統(tǒng)下游設備的投入成本。
Driving force for implementation
4.5.2.1.8 實施動力(該技術的優(yōu)勢)
? The FGC residues and fly ash can be separated and treated/recycled separately.
煙氣凈化的副產(chǎn)物和飛灰可以分開處理和回收。
? Smaller capacity downstream FGC equipment is required (dust loads are reduced).
下游設備處理容量減少(如:選型可以適當減小,因為粉塵濃度已經(jīng)降低了)
? Improvements in the operation of downstream FGC systems.
改善了下游設備的運行工況。
? Preference for the removal of PCDD/F before wet scrubbing to reduce the memory effect.
在濕法洗滌塔前能去除二噁英/呋喃,以減少記憶效應。
Example plants
4.5.2.1.9 工廠案例
Widely applied in many incineration plants.
在許多焚燒廠廣泛應用
Reference literature
4.5.2.1.10 參考文獻[ 2, InfoMil 2002 ], [ 55, EIPPCB 2002 ], [ 64, TWG 2003 ]
4.5.2.2 Downstream dedusting
4.5.2.2 下游除塵(主除塵、拋光除塵)
Description
4.5.2.2.1 說明
This technique relates to either one of the following cases:
該技術通常應用于如下某一種情況:
?dedusting associated with dry and semi-wet processes in order to capture at the same time as dust the salts produced by the reaction between acid gases and alkaline reagents.
下游除塵通常和干法或半干法(SDA)工藝相結合以同時便捕捉反應塔中由酸性氣體和堿性脫酸劑生成的副產(chǎn)物和粉塵。
?the application of an additional flue-gas polishing system for the final reduction of dust emissions after other FGC components, before the final release of stack gases to the atmosphere.
應用作為一個額外的煙氣拋光系統(tǒng),為了最后在其他煙氣凈化系統(tǒng)工藝段后,通過煙囪排向大氣前,實現(xiàn)粉塵排放的最后控制。(韓國麻蒲,荷蘭代爾夫載爾。)
Technical description
4.5.2.2.2 技術說明
The main system used downstream of a dry or semi-wet FGC system is the bag filter.
干法或半干法煙氣凈化系統(tǒng)的下游通常使用的主除塵系統(tǒng)是布袋除塵。
The main systems used for flue-gas polishing are:
主除塵系統(tǒng)用于煙氣拋光的主要有:
? bag filters;
布袋除塵器;
? wet ESPs;
濕式電除塵;
? electrodynamic Venturi scrubbers;
電動文丘里洗滌塔;
? agglo-filtering modules;
凝集過濾模塊;
?ionising wet scrubbers. [ 74, TWG 2004 ]
離子濕法洗滌。
The individual techniques are described in Section 2.5.3.
單獨的技術描述在2.5.3章節(jié)中。
The addition of a final wet flue-gas treatment system can also be considered a polishing treatment after other systems that deal with acid gases, etc. This addition is generally made to specifically control HCl and SO2 emissions where they are highly variable; PCDD/F and mercury can also be removed with the use of carbon-impregnated polymer (plastic) material and with the addition of hydrogen peroxide respectively. These additional techniques are described in Sections 4.5.5.7, and 4.5.6.5. [ 64, TWG 2003 ] [7, TWG 2017]
在其他脫酸等工藝后布置一道最終的濕式煙氣處理系統(tǒng),通常被認為拋光處理。這種設計是為了進一步控制HCL和SO2,因為他們的波動性較大。
Polishing devices are also implemented to remove droplets (especially fine ones). They are generally implemented to prevent fouling in downstream devices such as an SCR system. [ 74, TWG 2004 ]
拋光設施也用于去除細小顆粒物(特別是超細粉塵)。他們通常用于防止下游設備(如SCR系統(tǒng))的污染。
Achieved environmental benefits
4.5.2.2.3 獲得環(huán)境效益
In addition to the further reduction of dust emissions, emissions to air of the following substances can also be reduced:
除了進一步減少了粉塵排放外,如下物質(zhì)也隨之減少排放:
?metals – as their emission concentrations are usually associated with dust removal efficiency;
金屬—因為他們的排放濃度通常與粉塵的去除效率相關;
?mercury and PCDD/F – where carbon (usually with alkaline reagent) is added as an absorbent on bag filters;
汞和二噁英/呋喃—活性炭(通常和堿性吸收劑一起)作為附在布袋表面的吸收劑。
? acid gases – where alkaline reagents are added to protect bag filters.
酸性氣體—堿性吸收劑被加入除塵器用于保護布袋。
The benefits of these additional reductions may be small where upstream techniques are already being applied to reduce the concentrations in the flue-gas to a low level.
如果上游工藝措施已經(jīng)將煙氣污染物濃度降低到一個非常低的水平,那么這種拋光除塵器所起到的作用就是很有限的了。
以上述案例應該就是作用很有限的代表了。
Furthermore, the use of two different systems for the removal of solids from the flue-gas enables the separation of fly ash from the FGC residues (salts from acid gas neutralisation). This may then allow the recovery of one or other fraction where suitable outlets exist.
此外,使用二種不同的除塵系統(tǒng)可以將煙氣固體顆粒物中的飛灰和脫酸副產(chǎn)物(主要是中和煙氣酸性物質(zhì)后得到的鹽類)實現(xiàn)分離。這可以使得對飛灰或副產(chǎn)物進行有效回收得以實現(xiàn)。
Environmental performance and operational data
4.5.2.2.4 排放性能和運行數(shù)據(jù)
Generally, similar dust emission levels can be achieved with upstream and downstream dedusting.
一般來說,上游除塵和下游除塵可達到同等的粉塵排放水平。
In the case of double dedusting, further reductions of emissions to air beyond that already achieved by other FGC components are as shown in the table below.
如果使用雙除塵技術,粉塵的減排能力將比其他煙氣凈化系統(tǒng)工藝段更好,正如下表所示。
Table 4.14: Emission levels associated with the use of BF flue-gas polishing systems
Table 4.14: 使用布袋除塵作為拋光系統(tǒng)(末端布置)的排放水平
Careful maintenance of bag filters is very important to ensure their effective operation and hence low emissions. The pressure drop across the bags is monitored in order to maintain a cake on the filter. It can also be used as a means to detect bag damage (such as irreversible fouling). Dust emissions can usually be controlled to a very low level, simply by observing the pressure drop more closely and adopting stricter criteria (i.e. less latitude allowed before maintenance action is taken) for bag replacement. Analysis of the filter media may also be used to assess the reagent dose rate required and to assess its condition and its remaining lifetime.
仔細對布袋除塵器進行維護對確保其運行效率和較低的排放水平是非常重要的。對布袋壓差的監(jiān)控是為了維持濾袋的濾餅層。這也是監(jiān)測布袋是否損壞的一個方法(例如:糊袋),粉塵排放通??梢员豢刂圃谝粋€非常低的水平,只要密切關注壓差和采用嚴格的換袋標準(在維護之前應當嚴格遵守)。濾料的化驗分析可以用于評估吸收劑的給料率,評估其狀況和剩余壽命。
Table 4.15: Operational data associated with the use of flue-gas polishing
Table 4.15: 與使用末端布置除塵相關的運行數(shù)據(jù)
Cross-media effects
4.5.2.2.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
The cross-media effects associated with double dedusting are identified in the following table.
下表列出了與雙重除塵相關的跨介質(zhì)效應。
Table 4.16: Cross-media effects associated with the use of additional flue-gas polishing
Table 4.16: 使用末端布置除塵在不同介質(zhì)下的影響
For this technique, the most significant cross-media effect is the consumption of energy due to the pressure drop across the bag filters.
對于這個技術,最顯著的跨介質(zhì)影響(能源消耗)來自于布袋除塵器壓降造成的能源消耗。
In particular, in the case of using two bag filters in series (even if separated), the potential benefits in terms of improved pollutant control need to be contrasted against the significantly higher fan power required to overcome the additional pressure drop caused by the second bag filter, and therefore higher electricity consumption.
特別是,在串聯(lián)2個布袋除塵器時(即使是分開的),需要對比平衡選擇“潛在地提高了污染物控制能力”和“克服由二級布袋除塵引起的額外的壓降而引起的風機功率明顯提高而造成的更多的電力消耗”。(這是個經(jīng)濟性問題,設計者需要考慮這一因素)
Technical considerations relevant to applicability
4.5.2.2.6 技術適用性的考慮
Flue-gas polishing (double dedusting) requires space for the additional process unit, which may be a limiting factor for existing plants
采用雙除塵公司的煙氣拋光設計,需要更多的額外場地來布置額外的工藝裝置,這對老廠改造來說是有難度的。(還有引風機壓頭余量)
Economics
4.5.2.2.7 經(jīng)濟因素
The key cost aspects of double dedusting are:
采用雙除塵技術的主要成本在于:
?increased capital costs due to the additional process unit;
因為增加了額外的工藝裝置而增加了投資成本;
?increased operating costs – mainly due to energy requirements for the pressure drop, provision of compressed air for back pulsing of the bag filter (if used), and additional maintenance costs.
運營成本增加—主要是壓降造成的成本,噴吹壓縮空氣和運行導致增加的成本。(如果是濕電的話,還有廢水處理成本,電耗等。)
Driving force for implementation
4.5.2.2.8 實施動力(該技術的優(yōu)勢)
Downstream dedusting is generally necessary when using dry or semi-wet FGC systems. For the specific case of double dedusting, driving forces for its use may include:
通常采用干法或半干法系統(tǒng)的時候,下游除塵器是必須的。在這種情況下,仍采用雙除塵的主要原因在于:
?compliance with legislation/local permit conditions that require additional reductions of dust, metals, dioxin and/or acid gas emissions;
依據(jù)法規(guī)或項目所在地的要求,進一步減少粉塵,重金屬,二噁英和/或酸性污染物排放。
?need for effective dedusting for a subsequent SCR process;
基于下游的SCR工藝需要,必須確保除塵的可靠運行。(否則就會國內(nèi)部分項目,出現(xiàn)催化堵塞或堿金屬中毒等)
?possibility to recycle the salts arising from the removal of acid gases;
回收脫酸后的副產(chǎn)物的目的;(個人理解:可能考慮分段噴入活性炭,噴入活性炭后,副產(chǎn)物利用可能受到影響,所以需要在二段設置除塵,在二段噴活性炭等,這樣一段捕捉下來的副產(chǎn)物就可以循環(huán)利用了。)
上面這個是不需要利用的返利,將消石灰和活性炭回噴到一級布袋,減少消耗量。
?where double bag filtration is used, recovering additional heat between the two bag filters enables operating the second filter at a lower, optimal temperature (around 140 °C) for activated carbon injection.
在使用雙除塵的情況下,回收2個除塵之間的熱量可以使二級除塵在更低的最佳溫度(大約140度)下操作,有利于活性炭的噴射反應。
Example plants
4.5.2.2.9 工廠案例
Downstream dedusting is applied at all plants fitted with dry or semi-wet FGC systems
所有采用干法或半干法工藝的煙氣凈化系統(tǒng)的工廠都裝有主除塵器。
There are examples of plants using double dedusting in Germany, Austria, France and the Netherlands.
德國、奧地利、法國和荷蘭都有采用雙除塵工藝的焚燒廠。
Reference literature
4.5.2.2.10 參考文獻
[ 3, Austria 2002 ], [ 2, dedusting associated with dry and semi-wet processes in order to capture at the same time as dust the salts produced by the reaction between acid gases and alkaline reagents. ], [ 64, TWG 2003 ]
下游除塵通常和干法或半干法(SDA)工藝相結合以同時便捕捉反應塔中由酸性氣體和堿性脫酸劑生成的副產(chǎn)物和粉塵。
4.5.3 Techniques to reduce acid gas emissions
4.5.3 脫酸技術
The sections that follow address:
以下各節(jié)說明:
?description and assessment of the performance generally achieved by the main techniques applied for acid gas reduction – including consideration of applicability to various situations;
對通常采用的主要脫酸技術進行描述和性能評估—包括各種應用情況下應考慮的問題;
?description and assessment of some other technological and procedural options relevant to acid gas removal.
與脫酸相關的其他技術和程序性因素的描述和評估。
4.5.3.1 Wet scrubbing systems
4.5.3.1 濕法洗滌系統(tǒng)
Description
4.5.3.1.1 說明
This technique is described in Section 2.5.4.
該技術的描述在2.5.4章節(jié)。
Technical description
4.5.3.1.2 技術說明
Wet scrubbers generally have at least two effective stages: the first at low pH removes mainly
HCl and HF as well as metals, the second stage is dosed with milk of lime, limestone suspension or sodium hydroxide and operated at a pH of 6–8 primarily for the removal of SO2. Scrubbers may sometimes be described as three or more stages – the additional stages generally being subdivisions of the first low pH stage for specific purposes.
濕法洗滌塔通常需要至少2個有效階段:第一需要在非常低PH的階段主要用于去除HCL和HF以及重金屬,第二階段是投加石灰乳,石灰石懸浮液或氫氧化鈉,PH控制在6-8以便主要脫除二氧化硫。洗滌塔有時可描述為三個或更多階段—附加段通常是第一個低pH階段的細分,用于特定目的。(典型的案例可以參考德國的諾因基興或丹麥lab做的4段洗滌塔,目前國內(nèi)只有日系的2段洗滌塔。)
Achieved environmental benefits
4.5.3.1.3 獲得環(huán)境效益
Wet FGC systems provide the highest removal efficiencies (for soluble acid gases) of all FGC
systems with the lowest excess stoichiometric factors. [ 74, TWG 2004 ]
濕法洗滌塔系統(tǒng)可以以“最低的過量化學計量比”(即鈣酸比,鈉酸比等)實現(xiàn)所有煙氣凈化系統(tǒng)中最高的去除效率(針對可溶性酸性氣體)。
Whilst single-stage filtration-based FGC systems (e.g. semi-wet, dry) combine and collect residues together, this is not generally the case with wet systems. The wet systems can treat HCl, HF and SO2 separately from dust, which is usually removed before. That said, wet systems do provide some additional reductions of the following substances:
基于單機除塵的煙氣凈化系統(tǒng)(如設置一級布袋的半干法、干法工藝)會將副產(chǎn)物和飛灰結合在一起收集,但濕法系統(tǒng)通常不會這樣。濕法系統(tǒng)可將HCl、HF和SO2與粉塵分開處理,通常粉塵在上游的除塵設施中就已經(jīng)去除了。那就是說,濕法系統(tǒng)確實可以進一步減少以下物質(zhì):
?Dust - where the scrubber capacity is large enough to prevent clogging (most usually a pre- dedusting stage is used before the wet scrubber to reduce dust loads and prevent operational problems), by up to 50 % of the dust input. [ 74, TWG 2004 ]
粉塵(濕法洗滌還具有除塵功能)—如果洗滌塔的設計能力足夠大就可以阻止系統(tǒng)堵塞(通常大部分情況下在濕法洗滌塔上游會設置預除塵以減少粉塵負荷避免出現(xiàn)操作問題),濕法洗滌塔可以具備高達50%的除塵效率。
?PCDD/F - if carbon-impregnated packing materials are used, a typical reduction of 70 % is achieved by a typical scrubbing system. However, multi-stage scrubbing systems packed with a sufficient volume of carbon-impregnated materials are able to guarantee emission levels well below 0.1 ng I-TEQ/Nm3 in MSWIs and HWIs. Activated carbon or coke may be added to the scrubber for a similar purpose, with similar removal efficiencies. In the absence of carbon additives, the removal rates are negligible. [ 74, TWG 2004 ] [7, TWG 2017]-Sweden
二噁英/呋喃(濕法脫除能力)—如果使用了“碳浸漬包裝材料”(我baidu和google找了半天沒找到準確的信息,估計是類似碳填充的封裝好的一種填料類物品。
http://www.alibole.com/qynews/0198a492/article-452913386.html 這個可以拿來試試 http://www.dginfo.com/chanpin-242667495/ ),那么濕法洗滌的去除率能達到70%。然而裝有足量 “碳浸漬包裝材料”的市政垃圾焚燒廠及生活垃圾焚燒廠的多級洗滌塔系統(tǒng)能夠保證排放水平低于0.1 ng I-TEQ/Nm3。可以通過加入活性炭或活性焦來使之具有相同的效率。如果沒有添加此類碳添加劑,那么是沒有什么去除效率的。
?Hg2+ - if a low pH (~1) first stage scrubber is used, and HCl concentrations in the waste provide for acidification of this stage, then mercury is removed as HgCl2; elemental mercury is in general not affected. [ 64, TWG 2003 ]
2價汞—如果使用一級低PH值的洗滌塔,廢棄物中的HCL濃度足夠在這段進行酸化,則汞可以通過形成HgCl2的化合物進行去除;元素汞通常不受影響。
?Other pollutants - when water-soluble pollutants like bromine and iodine are present in the raw gas, they may be condensed at the low temperatures in the scrubber and in this way enter the scrubber waste water.
其他污染物—當原煙氣中存在溴和碘等水溶性污染物時,它們可能在洗滌器中低溫冷凝,從而進入洗滌器廢水。
Environmental performance and operational data
4.5.3.1.4 排放性能和運行數(shù)據(jù)
The air emission levels generally achieved by plants fitted with wet scrubbers are shown in
Table 4.17.
配置濕法洗滌塔的焚燒廠的常規(guī)可達到的排放水平見表4.17。
Table 4.17: Emission levels associated with the use of wet scrubbers
Table 4.17: 使用濕法洗滌塔的相關排放水平
Table 4.18: Operational data associated with the use of wet FGC
Table 4.18: 使用濕法煙氣凈化系統(tǒng)的運行數(shù)據(jù)
The main operational issues are as follows.
主要操作問題如下:
PCDD/F build-up in wet scrubbers can be a problem, in particular from maintenance and start- up periods, and may require specific measures to be taken.
二噁英/呋喃 在濕法洗滌塔中的富集(是否是指記憶效應?)可能是個問題,特別是從維護到啟動的期間,需要采取具體的措施。(停機到下次啟動之前,一定要進去清理。)
Effluent treatment requires highly skilled operation to achieve low emission levels.
廢水處理需要高技術操作才能達到低排放的水平。
For effective operation, wet scrubbers require flue-gases that have already been dedusted using for example an ESP or BF. [ 64, TWG 2003 ]
為了有效地運行,在濕法洗滌塔上游的煙氣凈化系統(tǒng)需要先進行除塵,使用例如靜電除塵或布袋除塵。
Wet scrubbing enables flexibility in terms of the variation in the inlet concentrations of HCl, HF and also SO2 owing to its high buffer capacity. Sometimes additional treatment is required for mercury, for example: the injection of a complex builder in the basic scrubber; injection of activated carbon in the acidic scrubber; injection of oxidising agent or abatement in the gas phase with adsorbent. [ 64, TWG 2003 ]
基于濕法洗滌塔非常強的抗波動能力,它對入口的HCL,HF以及SO2的波動具有較強適應性。有時候汞需要額外的處理(是不是當HCL濃度高的時候不需要,自動生成HgCl2),例如:在堿洗塔(歐洲分為 酸洗acidic scrubber 和 堿洗basic scrubber)里面噴入額外助劑;在酸洗塔中噴入活性炭;在氣相階段隨吸附劑一起噴入氧化劑和消除劑;(???臭氧法?強制氧化法?)
Cross-media effects
4.5.3.1.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
Cross-media effects are identified in Table 4.19 below.
跨介質(zhì)影響在下表4.19中確定。
Table 4.19: Cross-media effects associated with the use of wet scrubber FGC
Table 4.19: 與使用洗滌煙氣凈化有關的跨介質(zhì)影響
For this technique, the most significant cross-media effects compared to other options are:
該技術與其他工藝相比,最顯著的跨介質(zhì)效果如下:
?lowest reagent consumption rates;
最低的吸收劑消耗率;
?lowest solid residue production rates;
最低的固體副產(chǎn)物排放率;
?higher water consumption;
最高的水耗;
?production of an effluent that requires management;
有廢水產(chǎn)生,需要進行處理;
?increased plume visibility;
增加了煙羽的可視性;
?PCDD/F build-up (memory effect) on scrubber plastic components requires addressing;
二噁英/呋喃,在吸收塔內(nèi)塑料部件上的積累(記憶效應)需要處理;(這個addressing有處理的意思,但這里是不是這個意思?)
?if the input temperature is too high the material used in the wet scrubber may be destroyed.
如果進入洗滌塔的煙氣溫度過高,可能塔內(nèi)材料會遭到損壞。
[74, TWG 2004 ]
Technical considerations relevant to applicability
4.5.3.1.6 技術適用性的考慮
The technique is generally applicable as long as there is a sufficient water supply.
只要當?shù)夭蝗彼?,該技術通常是普遍適用的。
Due to the low outlet temperature (approximately 70 °C), the flue-gas may need to be reheated for subsequent FGC systems, e.g. bag filters and SCR.
由于出口排煙溫度低(大約在70度,國內(nèi)如果脫白會更低),考慮到下游煙氣凈化系統(tǒng),如:布袋除塵和SCR系統(tǒng),煙氣需要進行在加熱。
Economics
4.5.3.1.7 經(jīng)濟因素
Estimated capital costs for the technique are as in the table below.
該技術的投資成本估算如下表所示。
Table 4.20: Estimated investment costs of selected components of wet FGC systems
Table 4.20: 濕法煙氣凈化系統(tǒng)的部件投資成本估算
The key cost aspects of this technique compared to the alternatives are:
與可替代的工藝相比這個技術的關鍵成本是:
?higher capital investment costs than other systems, mainly due to the effluent treatment plant and the higher number of process units required, which may be a limiting factor in particular at smaller non-hazardous waste incineration sites;
比其他系統(tǒng)更高的投資成本,是否廢水處理裝置和采用多少段(我理解為2段塔,3段塔或4段塔)工藝單元是影響成本的關鍵,也是小規(guī)模無害化垃圾焚燒場所無法使用的原因;
?operational costs associated with disposal of residues may be lower, due to the lower specific residue production [ 74, TWG 2004 ];
由于副產(chǎn)物外排量較低,處置副產(chǎn)物的運行成本較低;
?labour costs are higher due to the increased complexity of the system.
由于系統(tǒng)更為復雜,所以勞動力成本更高。
Driving force for implementation
4.5.3.1.8 實施動力(該技術的優(yōu)勢)
?Achievement of particularly low and stable acid gas emission levels.
實現(xiàn)特別低且穩(wěn)定的酸性氣體排放控制水平。
?Reduction of disposal costs for flue-gas treatment residues.
減少煙氣凈化系統(tǒng)副產(chǎn)物的處置成本。
?Possibility to recover HCl, salt, gypsum.
可以實現(xiàn)HCL,鹽類和石膏的回收。
?Particularly difficult to predict/control input waste composition.
特別難預測和控制的廢棄物組成。(個人理解為垃圾成分不確定,煙氣系統(tǒng)要面對的就是污染物的波動和高入口濃度,濕法是最佳處理方案,國內(nèi)浙江,特別是溫州這個區(qū)域經(jīng)常會有這個需求)。
?Input waste may contain high and variable loads of acid gas precursors or metals (e.g. ionic mercury) [ 74, TWG 2004 ].
輸入廢棄物可以適應濃度較高且波動較大的酸性氣體的前驅物或金屬(如:離子汞)。
?Reduction of ammonia emissions.
減少氨逃逸。
Example plants
4.5.3.1.9 工廠案例
Wet flue-gas scrubbing is widely used throughout Europe for the full range of waste types.
煙氣濕法洗滌工藝廣泛應用于整個歐洲的各類型廢物處理工廠。
Reference literature
4.5.3.1.10 參考文獻
[ 1, UBA 2001 ], [ 2, InfoMil 2002 ], [12, Achternbosch, 2002], [ 64, TWG 2003 ]
4.5.3.2 Semi-wet scrubbing systems
4.5.3.2 半干法系統(tǒng)
Description
4.5.3.2.1 說明
This technique is described in Section 2.5.4.
該技術在2.5.4章節(jié)描述。
Technical description
4.5.3.2.2 技術說明
The diagram below shows a typical semi-wet FGC system, with a reactor on the left and downstream deduster on the right.
下圖顯示了一個典型的半干法煙氣凈化工藝,左邊是一個反應塔右邊是一個下游除塵器。
Figure 4.6:Typical design of a semi-wet FGC system
Figure 4.6:半干法煙氣凈化系統(tǒng)的典型設計
Achieved environmental benefits
4.5.3.2.3 獲得環(huán)境效益
There is no effluent discharge from semi-wet scrubbers as the amount of water used is generally lower than with wet scrubbers and it is evaporated with the flue-gases. If of suitable quality,
other site waste water (e.g. rainwater) may be sent to the FGC system. [ 74, TWG 2004 ]
半干法反應器沒有廢水排放,其用水量比濕法洗滌要小,水跟隨煙氣蒸發(fā)了。如果水的品質(zhì)合適,其他部位的廢水(如:雨水)可以拿來使用。
Semi-wet FGC systems provide high removal efficiencies (for soluble acid gases). Emission levels can be decreased by adjusting the reagent dosing rate and design point of the system, but generally at the cost of increased reagent consumption and residue production rates.
半干法煙氣凈化系統(tǒng)提供較高的去除效率(針對可溶性的酸性氣體)。通過調(diào)節(jié)吸收劑的添加量和系統(tǒng)的設計點(是不是排煙溫度?看4.5.3.9.4。),排放可以污染物排放水平,但是這通常會增加吸收劑的消耗量和副產(chǎn)物的排放量。
Semi-wet systems are used with fabric filters to remove the reagents added and their reaction products. Reagents, other than alkaline reagents, can also be added to adsorb other flue-gas components (e.g. activated carbon for mercury and PCDD/F).
半干法系統(tǒng)通常使用布袋除塵器去脫除吸收劑和反應副產(chǎn)物。除了堿性吸收劑外,其他試劑也可以被用于吸收其煙氣污染物組分(例如:將活性炭用于汞和二噁英/呋喃)。
They are most commonly used as a single-stage reactor/filter for the combined reduction of:
他們通常采用單級反應器/布袋,然后組合在一起來減少如下污染物:
?acid gases- removed by the alkaline reagent;
酸性氣體—通過堿性吸收劑去除;
?dust- filtered by the fabric filter;
粉塵—被布袋除器過濾;
?PCDD/F- adsorbed if activated carbon is injected as well as alkaline reagent;
二噁英/呋喃—噴入的活性炭與堿性吸收劑一起吸附;
?Hg- adsorbed if activated carbon is injected as well as alkaline reagent.
汞—噴入的活性炭與堿性吸收劑一起吸附;
Environmental performance and operational data
4.5.3.2.4 排放性能和運行數(shù)據(jù)
The air emission levels generally achieved by plants fitted with semi-wet scrubbers are as follows.
安裝半干法工藝的焚燒廠可以達到如下排放水平。
Table 4.21: Emission levels associated with the use of semi-wet scrubbers
Table 4.21: 使用半干法工藝的排放水平
Table 4.22: Operational data associated with the use of semi-wet FGC
Table 4.22: 半干法工藝相關的運行數(shù)據(jù)
Most systems consist of only a reagent mixing unit (reagent plus water) and a spray tower, and then a bag filter – complexity is therefore lower than with wet FGC systems.
大部分系統(tǒng)組成僅僅是一個吸收劑制備單元(吸收劑加水)和噴霧干燥塔,然后一個布袋除塵—系統(tǒng)復雜性低于濕法煙氣系統(tǒng)。
The reagent handling and dosing require good management to ensure effective and optimised operation, particularly where heterogeneous waste types are treated, e.g. merchant HWIs.
吸收劑制備和給料需要非常好的管理來確保有效和優(yōu)化的運行操作,特別是復雜工況的垃圾,如:商業(yè)HWIs(是不是危險廢棄無?吃不準。)
Upstream HCl monitoring (see Section 4.5.3.9) improves optimisation of reagent dosing in these systems and allows management of peak loads of HCl, HF and SO2 without high reagent dosing rates.
上游HCL監(jiān)測(詳見4.5.3.9章節(jié))改進了這些吸收劑計量的優(yōu)化和使得對HCL,HF和SO2的峰值負荷管理不再需要很高的吸收劑使用量。
Some installations produce the Ca(OH)2 for the FGC system on site by slaking of CaO. Effective lime preparation can be critical to good operation, as can be controlling the risk of fouling in the injection device. The injectors have to be located and designed such that they can be easily maintained and/or replaced for cleaning. [ 74, TWG 2004 ]
部分煙氣凈化系統(tǒng)通過在現(xiàn)場增設裝置,用CaO熟化制備Ca(OH)2。有效的石灰制備對良好的運行是非常重要的,也可以有效控制噴射裝置的堵塞風險。噴射器的位置和設計必須使其易于維護和/或更換以便清理。
Bag filters require close monitoring and management to address bag damage and consequent releases. Differential pressure monitors are commonly used to indicate bag damage and monitor operation in general.
布袋除塵器需要密切的監(jiān)測和管理,以便解決布袋破損和隨后的粉塵超標。壓差監(jiān)測儀通常用于指示破袋和監(jiān)測操作。
Temperature requirements are critical. Care is required to ensure dew point corrosion in the bag filter is avoided – inlet gas temperatures of above 130–140 °C are usually used. At temperatures below 130 °C there may be problems due to the hygroscopic nature of the CaCl2 formed. Reagents usually require a specific temperature for optimal reaction conditions.
運行溫度是非常關鍵的。需要關注避開濾袋的露點腐蝕—除塵器入口煙氣溫度通常要高于130-140度。如果溫度低于130度就會出現(xiàn)吸濕性的CaCl2。(二水,四水氯化鈉?參見一下Niro的培訓手冊)吸收劑通常需要一個特殊的溫度來達到最佳反應條件。
It is reported that there may be operational problems when semi-wet FGC systems are used with very highly acidic polluted raw gases as this can lead to an increased risk of filter clogging.
報告稱當入口原煙氣中酸性污染物濃度非常高時,半干法煙氣凈化系統(tǒng)使用會遇到很多操作問題,這將導致布袋糊袋的風險增加。
The operational complexity of reactors and bag filters used in semi-dry systems can itself be decreased further by the use of a degree of pre-dedusting, e.g. use of a single-stage ESP, or by using non-sticky bag materials (see also Section 2.5.3.5). This avoids the problems of:
通過設置一些預除塵,半干法系統(tǒng)中的吸收塔和布袋除塵的操作難度會有所降低,如:使用一級電除塵,或使用防粘材料的布袋(詳見2.5.3.5章節(jié))。這可以避免如下問題:
? sticking of some zinc (and similar salts with low melting temperatures); and
部分鋅的粘念(和類似的低熔點鹽類);和
?hygroscopic salts forming sticky layers on the surface of the reactor. [ 64, TWG 2003 ]
在反應器表面形成粘性層的吸濕鹽。
Cross-media effects
4.5.3.2.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
Cross-media effects are identified in the following table.
跨介質(zhì)影響在下表中顯示。
Table 4.23: Cross-media effects associated with the use of semi-wet acid gas treatment
Table 4.23: 使用半干法脫酸工藝的跨介質(zhì)影響
For this technique, the most significant cross-media effect is higher residue production rates than for wet systems.
該技術的最主要的跨介質(zhì)影響是會比濕法產(chǎn)生更多的副產(chǎn)物。
Separate collection of fly ash is possible if this system is preceded by an ESP. This then increases separation of fly ash and FGC residues, which can be beneficial if separate treatment/recycling options exist for these residues.
如果該系統(tǒng)前置了一個靜電除塵器,那么飛灰可以單獨進行收集。這就促進了飛灰和煙氣凈化系統(tǒng)副產(chǎn)物的分離,從而使得副產(chǎn)物的循環(huán)利用和分離處理的實現(xiàn)獲得更多益處。
The semi-wet FGC system is often applied as a single-stage multi-reactor. Such systems usually have lower energy requirements than more complex multistage FGC systems.
該半干法系統(tǒng)通常作為一個單級多用途反應器使用。這類系統(tǒng)的能耗通常低于哪些多級復雜的煙氣凈化系統(tǒng)。
Technical considerations relevant to applicability
4.5.3.2.6 技術適用性的考慮
The technique is generally applicable.
該技術普遍適用。
Due to the outlet temperature (120–170 °C), the flue-gas may need to be reheated for some subsequent FGC systems, e.g. SCR.
由于其出口溫度(120-170度),為了下游煙氣凈化系統(tǒng)(如:SCR系統(tǒng))的需要,其煙氣需要進行再加熱。
Economics
4.5.3.2.7 經(jīng)濟因素
Capital cost information for the technique is shown in the table below.
該技術的投資成本如下表所示。
Table 4.24: Estimated investment costs of selected components of typical semi-wet FGC systems
Table 4.24: 典型的半干法煙氣凈化系統(tǒng)的選定部件投資成本估算
Key operational factors of this technique are:
該技術的關鍵操作點是:
?investment costs are lower than for wet FGC systems, especially for relatively small capacities [ 2, InfoMil 2002 ]; possible higher cost of disposal of the higher quantity of residues produced (than wet systems);
投資成本低于濕法煙氣凈化系統(tǒng),對規(guī)模較小的焚燒廠而言更甚;副產(chǎn)物的量和處置成本相對較高(與濕法系統(tǒng)對比而言);
?reduced labour cost (compared to wet systems) due to the lower complexity, particularly because it avoids the costs of operating an effluent treatment plant;
由于復雜性相對較低,人員成本會減少(與濕法系統(tǒng)對比而言),特別是因為半干法系統(tǒng)避免了廢水處理島的運行成本。
?increased alkaline reagent cost due to higher stoichiometric ratios.
由于半干法需要更高的化學計量比,其堿性吸收劑的成本較高;
Driving force for implementation
4.5.3.2.8 實施動力(該技術的優(yōu)勢)
?Capability to deal with moderate and moderately variable inlet flue-gas loads.
適用于中等和中等波動的入口煙氣負荷(個人理解包括:污染物濃度和煙氣量波動)。
?No production of effluent.
無廢水排放。
?Lower investment cost than for a wet scrubber.
比濕法洗滌塔投資要低。
?Water consumption lower than for a wet scrubber.
比濕法洗滌塔的水耗要低。
?Lower plume visibility than with wet systems. [ 64, TWG 2003 ]
比濕法洗滌的有色煙羽的程度要輕。
Example plants
4.5.3.2.9 工廠案例
Widely used in Europe, e.g. the UK, Germany, France and Denmark.
在歐盟廣泛使用,如:英國,德國,法國和丹麥。
Reference literature
4.5.3.2.10 參考文獻
[1, UBA, 2001] [ 2, InfoMil 2002 ] [3, Austria, 2002] [12, Achternbosch, 2002] [26, RSP 1999], [54, dechefdebien, 2003] [ 64, TWG 2003 ]
4.5.3.3 Dry FGC systems
4.5.3.3 干法煙氣凈化系統(tǒng)
Description
4.5.3.3.1 說明
This technique is described in Section 2.5.4.
該技術描述詳見2.5.4章節(jié)。
Technical description
4.5.3.3.2 技術說明
Lime (e.g. hydrated lime, high specific surface area lime) and sodium bicarbonate are commonly used as the alkaline reagents. The addition of activated carbon provides for the reduction by adsorption of mercury and PCDD/F emissions.
石灰(例如:熟石灰,高比表面積石灰)和小蘇打是通常使用的堿性吸收劑。通過加入活性炭吸收汞和二噁英/呋喃來實現(xiàn)減排。
Finely ground sodium bicarbonate, when injected into hot gases (above 160 °C), is converted to sodium carbonate of high porosity and hence is effective for acid gas absorption. [59, CEFIC
2002], [7, TWG 2017]- CEWEP-ESWET
研磨小蘇打,當噴入到高溫煙氣(高于160度),轉化為高孔隙率的碳酸鈉,因此對酸性氣體吸收有效。
Achieved environmental benefits
4.5.3.3.3 獲得環(huán)境效益
With this technique, it is generally not possible to reach the same very low emission levels as with other FGC systems without increasing reagent dosing rates and consequent residue generation. Reagent recycling can reduce these cross-media effects to some degree, but can lead to operational difficulties related to reagent dosing systems.
使用該技術,很難如使用其他煙氣凈化工藝一樣,達到非常低的排放水平,除非靠增加吸收劑給料率和進而副產(chǎn)物排出量也會增加。吸收劑循環(huán)可以在一定程度上減少跨介質(zhì)影響,但是可能導致吸收劑給料系統(tǒng)的操作難度。
Environmental performance and operational data
4.5.3.3.4 排放性能和運行數(shù)據(jù)
Technical developments have enabled significant improvements over the last decade in the
performance of dry systems.
在過去十年中,技術的發(fā)展使干法煙氣系統(tǒng)的性能有了顯著的改善。
The air emission levels generally achieved by plants fitted with dry FGC are as follows.
安裝干法煙氣凈化系統(tǒng)的工廠排放通常可以達到如下水平。
Table 4.25: Emission levels associated with the use of hydrated lime in dry FGC processes
Table 4.25: 使用消石灰干法煙氣凈化系統(tǒng)的的排放水平
Table 4.26: Emission levels associated with the use of sodium bicarbonate in dry FGC processes
Table 4.26: 使用小蘇打干法煙氣凈化系統(tǒng)的的排放水平
Table 4.27: Operational data associated with the use of dry FGC
Table 4.27: 使用干法系統(tǒng)的相關運行數(shù)據(jù)
Dry reagents need to be handled in such a manner as to prevent dust emissions, e.g. emissions from loading silo breather vents.
干式吸收劑的處理應能防止粉塵的排放,如:裝載粉倉通氣孔的排放。
Some installations produce the Ca(OH)2 for the FGC system on site by slaking of CaO. Effective lime preparation can be critical to good operation, as can be controlling the risk of fouling in the injection device. The injectors have to be located and designed such that they can be easily maintained and/or replaced for cleaning. [ 74, TWG 2004 ], [7, TWG 2017]
一些裝置通過現(xiàn)場熟化生石灰來為煙氣凈化系統(tǒng)制備消石灰。有效的石灰制備是良好運行的關鍵,也是控制干粉噴射裝置堵塞風險的重要原因。噴射裝置應該布置和設計在易于維護和/或清理更換。
It is reported that the use of operating temperatures above approximately 210 °C may give rise to a deterioration in the PCDD/F and mercury adsorption performance of injected carbon reagents. [7, TWG 2017]-CEFIC
有報道稱,使用高于大約210度的運行溫度可能導致活性炭吸附劑對二噁英/呋喃和汞的吸附能力減弱。
Cross-media effects
4.5.3.3.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
Cross-media effects are identified in the table below.
跨介質(zhì)影響詳見下表。
Table 4.28: Cross-media effects associated with the use of dry FGC
Table 4.28: 與使用干法煙氣凈化系統(tǒng)有關的跨介質(zhì)影響
The most significant cross-media effect of this technique is the production of solid residues, which, all other parameters being equal, is generally greater than with wet systems. The excess may be reduced somewhat by residue recirculation.
該技術最顯著的跨介質(zhì)影響就是副產(chǎn)物的量,在邊界條件相當?shù)那闆r下,通常其副產(chǎn)物量是大約濕法系統(tǒng)的。當使用物料循環(huán)系統(tǒng),副產(chǎn)物可能會減少。
With sodium bicarbonate, the solid residues are more soluble than with hydrated lime, but significantly lower in quantity. Residues from bicarbonate systems, if separated from the fly ashes, may be treated and recycled in the chemical industry (established practice in France and Italy). [ 74, TWG 2004 ], [7, TWG 2017]-CEFIC
在使用小蘇打時,副產(chǎn)物比使用消石灰時更容易溶解,但是排放量明顯減少。來自碳酸氫鹽的副產(chǎn)物如果跟飛灰相分離后,還可以在化學工業(yè)中進行處理和回收(在法國和意大利有投產(chǎn)案例)。
Technical considerations relevant to applicability
4.5.3.3.6 技術適用性的考慮
The technique is generally applicable.
該技術普遍適用。
Economics
4.5.3.3.7 經(jīng)濟因素
Capital cost and system design considerations:
投資成本和系統(tǒng)設計需要考慮的因素:
?Lower capital costs than for semi-wet systems.
比半干法的投資成本更低。
?Higher possible operating temperatures can lead to savings for flue-gas reheating, e.g. for
SCR.
可以使用更高的運行溫度從而降低了煙氣再熱的運行成本,如:下游要使用的SCR。
?Reagent slurry handling/mixing unit not required with dry systems.
干法煙氣系統(tǒng)不需要吸收劑漿液制備系統(tǒng)。
Operating cost considerations relative to other techniques:
與其他煙氣技術相比運行成本要考慮的因素:
? increased reagent consumption rates, compared to wet FGC;
與濕法煙氣凈化系統(tǒng)相比,增加了吸收劑的消耗率;
? increased disposal costs for residues, compared to other FGC systems;
與其他煙氣凈化系統(tǒng)相比,增加了副產(chǎn)物的處置成本;
? savings for treatment/disposal because of lack of effluent.
由于沒有廢水,省下了廢水的處理和處置的成本。
Driving force for implementation
4.5.3.3.8 實施動力(該技術的優(yōu)勢)
The simplicity of such systems is the main reason for their use.
該技術簡單是使用它的主要原因。
The lower energy consumption compared to other FGC options, and the lower possible boiler outlet temperatures allowed by the absence of a temperature drop in dry FGC, also make these systems attractive from the point of view of energy recovery.
與其他煙氣凈化系統(tǒng)技術相比,更低的能源消耗(電耗),可以適用更低的鍋爐出口排煙溫度因為干法煙氣凈化系統(tǒng)不需要溫降段,從能源回收角度來講使得該技術更具吸引力。
Restrictions on water supply and outlets make the use of dry FGC systems favourable. When water discharges are forbidden, dry (and semi-dry) systems are favoured.
對供水限制和限制排放廢水的情況下,使用干法煙氣凈化工藝更為有利。在廢水零排放時,干法(和半干法)工藝是最佳選擇。
Dry systems provide further advantages where a visible plume has to be avoided.
采用干法系統(tǒng)還更有助于那些要求避免出現(xiàn)煙羽的地方。
Example plants
4.5.3.3.9 工廠案例
The technique is widely used throughout Europe. Over 240 plants are operating in more than 10
European countries, and Japan and the US.
該技術在歐洲廣泛應用。在超過10個歐洲國家,日本和美國有240做焚燒廠采用了該技術。
There are examples of merchant HWIs using dry systems in France and Germany.
在法國和德國還有一些商業(yè)危險廢棄物焚燒廠使用干法煙氣凈化系統(tǒng)的案例。
Reference literature
4.5.3.3.10 參考文獻
[ 59, CEFIC 2002 ], [ 2, InfoMil 2002 ], [ 64, TWG 2003 ]
4.5.3.4 Addition of wet scrubbing as a flue-gas polishing system after other FGC techniques
4.5.3.4 在其他煙氣凈化技術末端增加濕式洗滌塔作為拋光系統(tǒng)
Description
4.5.3.4.1 說明
It is possible to consider that the addition of a final wet flue-gas treatment system, or flue-gas condensation, is a polishing treatment after other systems that deal with acid gases, etc. This
addition is generally made to control HCl and SO2 emissions where they are high or variable. [
74, TWG 2004 ]
可以認為,在其他系統(tǒng)之后追加一道濕法洗滌的煙氣凈化系統(tǒng)或者煙氣冷凝系統(tǒng),是一種處理酸性氣體等的拋光處理方式(精細化處理)。這個額外裝置通??梢杂脕硖幚砣肟跐舛容^高或者波動較大的HCL和SO2的。
Technical description
4.5.3.4.2 技術說明
Flue-gas polishing is typically performed in packed bed wet scrubbers. A usual feature of wet
scrubbing in the polishing position is that HCl, SO2, HF and possibly mercury can be removed in one common stage rather than in two separate stages. NaOH can be added to improve the removal of SO2 and HF. The process water may be injected into the furnace or into the upstream dry flue-gas cleaning system for waste-water-free operation. Energy recovery by condensation can be integrated into the system, and the occurrence of wet plume can be avoided by reheating the flue-gas by the addition of a steam heater or by a gas-gas heat exchanger without the need for an additional energy supply.
煙氣拋光處理(高效脫除)通常是在填料塔中完成的。一個典型的特征是,當濕法洗滌在拋光處理的時候,HCL,SO2,HF以及可能的汞是在同一級塔中完成去除的,而不是在分開的二級塔中分別完成的。加入NaOH可以提高SO2和HF的去除率。廢水可以噴入爐膛或在上游的干法煙氣凈化段,從而實現(xiàn)不需要廢水的排放。從冷凝段回收的能源可以繼續(xù)返回系統(tǒng)使用,通過使用蒸汽加熱器或氣氣換熱器再熱(低溫)煙氣可以避免濕煙羽的出現(xiàn),而不需要額外的能源消耗。(冷凝回收的熱量夠平衡這個煙氣再熱嗎?沒算過。)
Achieved environmental benefits
4.5.3.4.3 獲得環(huán)境效益
Increased reliability in acid gas (HCl, HF, SO2) emission reductions down to levels at the lower end of the ranges achievable with wet scrubbing (see Section 4.5.3.1).
增加了酸性氣體(HCL,HF,SO2)減排的可靠性,能達到使用濕法洗滌所能達到的最低限度。(詳見4.5.3.1章節(jié))
The consumption of sorbent and the related production of residues in the upstream dry system may be decreased due to the high efficiency and low stoichiometric factor of the polishing scrubber.
吸收劑的消耗量和上游干法脫酸系統(tǒng)中的副產(chǎn)物可以減少,因為拋光洗滌塔的高效脫除能力和較低的化學計量比(鈣酸比,鈉酸比等等)。
Environmental performance and operational data
4.5.3.4.4 排放性能和運行數(shù)據(jù)
See Section 4.5.3.1.
詳見4.5.3.1。
Cross-media effects
4.5.3.4.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
See Section 4.5.3.1.
詳見4.5.3.1。
Technical considerations relevant to applicability
4.5.3.4.6 技術適用性的考慮
See Section 4.5.3.1.
詳見4.5.3.1。
Economics
4.5.3.4.7 經(jīng)濟因素
The typical investment cost reported for a scrubber sized for treating a 100 000 Nm3/h gas flow is EUR 2 million including circulation pumps. An additional investment of around EUR 100 000 may also be required for a reheater or fiberglass-reinforced plastic stack pipe.
報告稱處理100000Nm3/h煙氣量的濕法洗滌塔的典型投資成本在200萬歐元,包括了循環(huán)泵。再加熱器或玻璃鋼煙囪再需10萬歐元的額外投資。
Operating costs have been reported as EUR 10–15/h for electricity (additional fan pressure drop of typically 1 200 Pa) and circulation pump operation. The NaOH cost depends on the design.
報告稱運行成本為10-15歐元/小時,用于電耗(額外的引風機壓損通常為1200pa)和循環(huán)泵的運行。NaOH的運行成本基于設計情況。
See also Section 4.5.3.1.
詳見4.5.3.1。
Driving force for implementation
4.5.3.4.8 實施動力(該技術的優(yōu)勢)
See Section 4.5.3.1 for the driving forces for the use of wet FGC in general.
詳見4.5.3.1章節(jié)的濕法煙氣凈化的動因。
Where emissions of acid gases are high or variable, the addition of a polishing stage may be driven by legislation requiring improved flue-gas cleaning related to peak concentrations of pollutants. The technique is thus most suited to wastes that have high and variable concentrations of chlorine or other acid-forming components (e.g. hazardous wastes or MW that includes industrial wastes).
當酸性氣體的入口濃度高且波動較大時,可以通過立法增加拋光(濕法)段來改善煙氣凈化應對峰值濃度的污染物。因此,該技術非常適合處理哪些具有高入口濃度且波動較大的含有氯化物或其他酸性化合物的垃圾(如:危險廢棄物或包括工業(yè)廢棄物的市政垃圾)。
The addition of a polishing stage may also be driven by savings in reagent costs in the upstream dry flue-gas cleaning system.
節(jié)約上游干法煙氣凈化系統(tǒng)的吸收劑運行成本也是增加拋光(濕法)段的動因之一。
Example plants
4.5.3.4.9 工廠案例
Many plants in Scandinavia and WTE ACCAM Busto Arsizio (IT) (IT01); Usine de Fort-De-
France (FR) (FR46); Halluin (FR) (FR92).
斯堪的納維亞的很多焚燒廠(包含挪威、瑞典和丹麥)和意大利的ACCAM Busto Arsizio焚燒廠;法國Usine de Fort-De-France焚燒廠;法國Halluin焚燒廠;
Reference literature
4.5.3.4.10 參考文獻
[ 64, TWG 2003 ], [ 97, Denmark et al. 2015 ]
4.5.3.5 Recirculation of FGC residues in the FGC system
4.5.3.5 物料循環(huán)流化煙氣凈化系統(tǒng)
Description
4.5.3.5.1 說明
Residues collected in the bag filters used for dry, semi-wet and similar (but not wet) FGC
systems (see also Sections 4.5.3.2, 4.5.3.3 and 4.5.3.8) usually contain a significant proportion of unreacted flue-gas treatment reagents, as well as the fly ash and other pollutants removed from the gas stream. A proportion of the accumulated residues can be reactivated and recirculated within the FGC system.
從干法,半干法或類似煙氣凈化系統(tǒng)(除了濕法)中布袋除塵收集下來的副產(chǎn)物(詳見4.5.3.2,4.5.3.3.和4.5.3.8章節(jié))通常包括了比例較高的未與煙氣反應的吸收劑,以及從煙氣中去除的飛灰和其他的污染物。一部分副產(chǎn)物可以通過煙氣凈化系統(tǒng)的再循環(huán)系統(tǒng)進行反應。
Technical description
4.5.3.5.2 技術說明
Because of the recirculation, the size of the FGC is generally increased to accommodate the
additional volume of recirculating material.
由于再循環(huán),煙氣凈化系統(tǒng)的選型尺寸通常會放大以滿足再循環(huán)物料的增量。(如:CFB煙氣工藝我們的過濾風速通常會略低)
The technique is particularly beneficial in the case of techniques that operate with a higher stoichiometric excess, and less relevant for the more efficient once-through system in which little unreacted reagent remains without recirculation. Analyses of the FGC residues may be carried out to determine the proportions of reacted and unreacted reagent.
再循環(huán)技術對那些本身化學計量比特別高的煙氣工藝特別有效,但是對那些單次通過就具有很高反應效率的技術沒有作用,因為那類工藝下幾乎沒什么未反應的吸收劑還殘留。(如:濕法洗滌工藝,對于鈉堿法是否有需要還不清楚工程反饋數(shù)據(jù),今后有純小蘇打干法項目可以試試副產(chǎn)物的成分化驗。)可以對煙氣凈化系統(tǒng)的副產(chǎn)物取樣分析以便確定反應完的和未反應完的吸收劑的比例。
The reactivation of unreacted reagents before reuse in the FGC process may take place by:
對未反應的吸收劑在煙氣凈化系統(tǒng)中在使用前的再活化可以通過以下方式進行:
? water addition and high residue recirculation rates;
通過加水和將副產(chǎn)物的循環(huán)倍率調(diào)到高倍率;
? low-pressure steam addition and medium residue recirculation rates;
通過加入低壓蒸汽并將副產(chǎn)物的循環(huán)倍率調(diào)到中等倍率;
? maturation of unreacted reagents and fly ash before recirculation into the FGC process.
未反應完的吸收劑和飛灰在循環(huán)回煙氣凈化系統(tǒng)前進行熟化。(熟化是加水嗎?不太確定)
Achieved environmental benefits
4.5.3.5.3 獲得環(huán)境效益
The recirculation of reagents within the system, combined with water/low-pressure steam addition or maturation, has the following advantages:
在系統(tǒng)內(nèi)的吸收劑再循環(huán),與水/低壓蒸汽或熟化相結合,具有以下優(yōu)勢:
? reduced reagent consumption (compared to dry and semi-wet systems);
減少吸收劑的消耗量(與干法和半干法系統(tǒng)相比);
? reduced solid residue production (contains less unreacted reagent);
減少固體副產(chǎn)物的產(chǎn)量(因為包含了更少的未反應的吸收劑);
? improved control of acid gas peaks (the recirculation results in a higher reagent buffer).
提高了對峰值酸性污染物排放的控制(物料循環(huán)導致了一個更高的吸收劑緩沖,也就是提高了與酸性氣體的接觸概率)。
These techniques are reported to be able to cope with the inlet concentrations associated with most waste types, including variable inlet concentrations that may arise for instance when incinerating merchant hazardous wastes.
據(jù)報道,這些技術能夠處理大部分污染物類型的入口濃度,包括在焚燒商業(yè)危險廢棄物時可能出現(xiàn)的波動較大的入口污染物濃度。
Environmental performance and operational data
4.5.3.5.4 排放性能和運行數(shù)據(jù)
Table 4.29: Operational data associated with the use of residue recirculation
Table 4.29: 使用再循環(huán)系統(tǒng)相關的運行數(shù)據(jù)
Reagent injection and residue bleed rates require optimisation to prevent adsorbent loading and eventual substance breakthrough (e.g. mercury and PCDD/F adsorbed on carbon).
吸收劑噴入和副產(chǎn)物排除的速率需要優(yōu)化,以防止吸收劑的吸附能力過載和最終物質(zhì)突破(個人理解是吸附飽和,進而超標)(例如:汞和二噁英/呋喃在活性炭上吸附)
Moisture levels require monitoring and control to maintain the acid gas adsorption efficiency. Upstream HCl and SO2 monitoring is used to optimise alkaline reagent/water/low-pressure steam dose rates.
煙氣濕度水平需要進行檢測和控制以便控制酸性氣體的吸收效率。上游的HCL和SO2監(jiān)測可以用于優(yōu)化堿性吸收劑/水/低壓蒸汽的給料率。
Some parts of the FGC system volume must be larger to incorporate the additionally recirculated material.
煙氣凈化系統(tǒng)的部分設備選型必須放大以便適應額外的循環(huán)物料。(如:布袋除塵器的選型。)
The reduction of emissions to air and emission levels achieved with these processes in combination with a bag filter and addition of reagent, are as follows.
將物料循環(huán)工藝與布袋除塵器和添加吸收劑相結合,可以減少空氣污染物排放和降低排放水平,具體如下:
Table 4.30: Emission levels associated with the use of intermediate systems
Table 4.30: 使用中間系統(tǒng)的排放水平
Cross-media effects
4.5.3.5.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
This technique enables the reduction of the amount of solid residues produced, as it is lower than without recirculation.
該技術可以減少固體副產(chǎn)物的產(chǎn)生量,它比沒有物料循環(huán)的排放量要低。
The reported reagent stoichiometry is in the range 1.5–2.5 depending on the implemented technology. A better stoichiometric ratio is achieved with low-pressure steam than with water addition or maturation.
據(jù)報告稱該技術的吸收劑的化學計量比(鈣酸比,鈉酸比)范圍在1.5-2.5,具體取決于所采用的技術(是指基于干法的物料循環(huán),還是半干法的物料循環(huán),個人理解半干法的物料循環(huán)化學計量比肯定更低)。通過加入低壓蒸汽會獲得比加水或熟化更好的化學計量比。
Water/low-pressure steam consumption depends on the inlet flue-gas temperature.
水/低壓蒸汽的消耗量取決于入口的煙氣溫度。
Plume visibility is very low due to the minimal amount of water/low-pressure steam used for conditioning.
由于用于調(diào)節(jié)的水/低壓蒸汽量最小,煙羽的可見度非常低。
In some cases, increases in mercury releases have been reported. Consideration of the mercury input rates and the provision of sufficient mecury removal may therefore be required to control this.
在有些案例中,有報告稱采用物料循環(huán)后汞的排放量有所升高。因此需要控制和考慮汞的入口濃度和提供足夠的汞的脫除能力。
Technical considerations relevant to applicability
4.5.3.5.6 技術適用性的考慮
The technique is generally applicable in combination with FGC systems other than wet systems.
該技術通常可應用于除濕法系統(tǒng)以外的其他煙氣凈化系統(tǒng)(如:干法,半干法)。
The recirculation of FGC residues requires a larger bag filter and additional space to accommodate the recirculation/reactivation/maturation equipment.
煙氣凈化系統(tǒng)物料再循環(huán)工藝需要一個選型較大的布袋除塵器和額外的空間來容納再循環(huán)/再活化/熟化等設備。(活化設備是個啥?阿爾斯通的增濕活化器?有可能)
Economics
4.5.3.5.7 經(jīng)濟因素
Capital costs are reported to be somewhat lower than for wet and semi-wet systems due to the
reduced number of process components and consequently the smaller footprint, but slightly higher than for dry FGC without recirculation.
報告稱,投資成本低于濕法和半干法系統(tǒng),因為減少了工藝設備,因此占地面積也減少,但是投資比沒有物料循環(huán)系統(tǒng)的干法煙氣凈化系統(tǒng)要稍微高些。
Operating costs, compared with dry FGC without recirculation, are reduced by the lower reagent consumption (improved stoichiometric ratio compared with dry systems) and the reduced residue disposal costs.
運行成本與沒有物料循環(huán)系統(tǒng)的干法系統(tǒng)相比則更低,因為吸收劑消耗量減少(與干法系統(tǒng)相比改進了化學計量比,更低)和副產(chǎn)物處置成本降低。
Driving force for implementation
4.5.3.5.8 實施動力(該技術的優(yōu)勢)
? Reduction of reagent consumption.
吸收劑消耗量減少。
? Reduction of residue production.
副產(chǎn)物產(chǎn)量減少。
? Limited space requirements.
需要的占地共空間較少。
? Limited process complexity.
工藝復雜程度相對較低。(對于物料循環(huán)干法工藝而言我不認為負責程度低。)
Example plants
4.5.3.5.9 工廠案例
Existing plants incinerating MSW, RDF and wood wastes in France, the UK, Italy, Sweden, Norway, Germany, Denmark and Spain.
在法國,英國,意大利,瑞典,挪威,德國,丹麥,西班牙的現(xiàn)有生活垃圾,RDF(垃圾衍生燃料)和木材廢料焚燒廠。
Reference literature
4.5.3.5.10 參考文獻
[ 57, Alstom 2003 ], [ 64, TWG 2003 ], [7, TWG 2017]-CEWEP-ESWET
4.5.3.6 Direct addition of alkaline reagents to the waste (direct desulphurisation)
4.5.3.6 垃圾直接添堿工藝(直接脫硫工藝,流化床)
Description
4.5.3.6.1 說明
This technique is described in Section 2.5.4.4. It is generally only applied to fluidised bed furnaces.
該技術在2.5.4.4章節(jié)中描述。它通常適用于流化床焚燒爐。
The alkaline reagent reacts in the furnace with acid gases to reduce the acid loads in the raw flue-gas passing to subsequent flue-gas cleaning stages.
堿性吸收劑在熔爐里面和酸性氣體反應,減少了煙氣下游煙氣凈化段中原煙氣的酸性負荷。(即減少了原煙氣中的原始排放濃度)
Technical description
4.5.3.6.2 技術說明
Adsorption within the furnace at high temperatures is much more effective for SO2 than for HCl; the main applications are therefore processes with a relatively high SO2 content, e.g. sludge incineration.
[ 74, TWG 2004 ]
在爐內(nèi)高溫情況下,SO2的脫除效率要比HCL高;因此,主要適用于SO2含量相對較高的工藝,如:污泥焚燒。
Achieved environmental benefits
4.5.3.6.3 獲得環(huán)境效益
Benefits include some reduction of raw gas loads and the reduction of emissions and reagent
consumption associated with the downstream FGC system.
該工藝獲得的效益來自于原煙氣中的污染物濃度減少導致的下游煙氣凈化設備的吸收劑消耗減少和污染物排放減少。
Environmental performance and operational data
4.5.3.6.4 排放性能和運行數(shù)據(jù)
The main advantage of this technique is that it may reduce corrosion problems in the boiler. As
the stoichiometric ratio is relatively high, it does not improve the overall FGC performance. [64, TWG 2003 ]
該技術的額主要優(yōu)點在于它可以技術那好鍋爐的腐蝕問題。因為其化學計量比相當高,所以它不會改善煙氣凈化系統(tǒng)的整體性能。(我理解是煙氣出來的殘余鈣會進入下游煙氣凈化系統(tǒng),導致下游煙氣系統(tǒng)不缺鈣,性能不會有啥變化和改善。也就是指下游煙氣凈化系統(tǒng)沒什么潛力再可挖了。)
Cross-media effects
4.5.3.6.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
For this technique, the most significant cross-media effects are:
該技術,最重要的跨介質(zhì)影響是:
? consumption of reagents in the furnace (but reduced consumption downstream);
爐內(nèi)吸收劑的消耗量(但是減少了下游煙氣設備的吸收劑消耗量);
? effects on the bottom ash quality since salts and the excess reagent are mixed with it;
由于爐內(nèi)脫酸產(chǎn)生的副產(chǎn)物鹽和過量的吸收劑,會混入鍋爐底灰;
?changing the composition of the flue-gas (SO2 to HCl ratio) can affect the performance of downstream FGC systems, can alter the PCDD/F profile and can cause corrosion problems in the FGC.
改變了煙氣組分(SO2和HCL的比例關系)會影響下游煙氣凈化系統(tǒng)的運行性能,也會改變二噁英/呋喃的屬性和導致煙氣凈化系統(tǒng)中的腐蝕。(是否是Niro培訓是提到的Sox和HCL的比例關系對脫硫效率的影響。詳見:4.5.3.7.4,HCL的脫除率可能很低。)
The addition of hydrated lime will not only affect the bottom ash quality, but also the composition and resistivity of the fly ash (i.e. there will be more Ca and more sulphurous compounds and higher dilution of pollutants with an increasing amount of FGC residues). [ 64, TWG 2003 ]
加入消石灰不僅會影響鍋爐底灰的品質(zhì),也會影響飛灰的組分和電阻率(即煙氣凈化系統(tǒng)會有更多含鈣和更多含硫化合物和更高稀釋度污染物的副產(chǎn)物產(chǎn)生)。
Technical considerations relevant to applicability
4.5.3.6.6 技術適用性的考慮
The technique is generally applicable to fluidised bed systems.
該技術通常適用于循環(huán)流化床鍋爐系統(tǒng)。
Economics
4.5.3.6.7 經(jīng)濟因素
The reduced flue-gas treatment costs need to be considered against the costs of adding the
reagent at the earlier stage.
減少煙氣處理的成本需要與上游添加(直接在垃圾中添加)吸收劑的成本相比較。
There are additional capital costs for the provision of reagent injection into the furnace/waste.
提供吸收劑噴入爐膛/垃圾,會產(chǎn)生額外的資金成本。
Driving force for implementation
4.5.3.6.8 實施動力(該技術的優(yōu)勢)
The technique is implemented as a retrofit at existing plants where there is only a limited possibility to increase the acid gas cleaning capacity of the FGC systems.
該技術通常適用于老廠改造,且該廠的煙氣凈化系統(tǒng)的脫酸能力增加的可能很有限。(個人理解老廠技改沒空間,沒資金之類的情況下,用用這種工藝。)
Example plants
4.5.3.6.9 工廠案例
SOGAMA, Cerceda (ES) (ES07.1/ES07.2); Area Impianti Bergamo (IT) (IT07); SNB, Moerdijk (NL) (NL06).
索加馬,塞爾塞達(西班牙,后面也是用半干法工藝的,且看了一下好像是爐排,不知道是不是后來改造過)(焚燒廠相關參考信息:
https://pdfs.semanticscholar.org/b01c/d2f354d3bfaba74e2e8669ccc35934b73a3f.pdf
https://www.industryabout.com/country-territories-3/2160-galiza/waste-to-energy/33779-sogama-cerceda-incineration-plant
https://ec.europa.eu/regional_policy/sources/docgener/evaluation/pdf/projects/sogama_galicia.pdf );
Impianti Bergamo地區(qū)(意大利);
SNB, Moerdijk(荷蘭)。
Reference literature
4.5.3.6.10 參考文獻
[ 1, UBA 2001 ], [ 64, TWG 2003 ]
4.5.3.7 Boiler injection of alkaline reagents (high-temperature injection)
4.5.3.7 爐內(nèi)噴堿工藝(高溫噴射工藝,爐排和回轉窯)
Description
4.5.3.7.1 說明
Direct injection of dedicated reagents into the boiler at high temperature, in the boiler post-
combustion area, to achieve partial abatement of the acid gases. Hydrated lime and dolime have been used as reagents.
直接向鍋爐的燃燒后區(qū)域,在很高的下噴入專用吸收劑,實現(xiàn)酸性氣體的部分脫除。消石灰和白云質(zhì)生石灰(MgO·CaO)通常被用作吸收劑。
Technical description
4.5.3.7.2 技術說明
In this technique, the hydrated lime reagent is injected and reacts with the acid gases directly in
the furnace, at optimal temperatures of 800–1 200 oC, to reduce the raw gas acid loads passing to subsequent flue-gas cleaning stages. Since adsorption at high temperatures is highly efficient
for SOX and HF removal, this reaction consumes significantly less reagent compared to achieving an equal removal rate at a lower temperature at the stage of the bag filter. The technique also flattens pollutant peaks, allowing the further reduction of reagent use in the
downstream flue-gas cleaning unit.
該技術,在800-1200度的最佳反應溫度下,在爐內(nèi)噴入消石灰吸收劑和煙氣中的酸性氣體直接反應,從而減少下游煙氣凈化段中煙氣的酸性污染物負荷。因為對Sox和HF而言,高溫吸附的效率是很高的,在同樣的去除率下,其(高溫段)吸收劑消耗量與布袋除塵器低溫段的消耗量相比要明顯減少。該技術還有助于解決峰值超標的問題,并可以減少下游煙氣凈化設備的吸收劑消耗。
Achieved environmental benefits
4.5.3.7.3 獲得環(huán)境效益
Benefits are reduction of raw gas loads and reduction of acid gas peaks, and reduction of emissions and reagent consumption in the downstream flue-gas cleaning unit.
其好處在于減少了原煙氣的酸性負荷和酸性煙氣的峰值,減少了下游煙氣凈化設備中酸性氣體的排放值和吸收劑消耗量。
Environmental performance and operational data
4.5.3.7.4 排放性能和運行數(shù)據(jù)
The reduction of SO2, SO3 and HF by 80–96 % and of HCl by 25–30 % (at the exit of the boiler) is reported with an injection rate of 3–8 kg hydrated lime per tonne of waste.
有報告稱,對每噸垃圾噴入3-8公斤的消石灰,其脫除SO2,SO3和HF的效率可達80-96%,對HCL脫除效率為25-30%(在鍋爐出口處的效率)。
Cross-media effects
4.5.3.7.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
Since an overall reduction in the use of reagents in the combined in-boiler and downstream flue-
gas cleaning systems is reported, no cross-media effects are expected.
據(jù)報告稱,因為在鍋爐和下游煙氣凈化系統(tǒng)中使用試劑的總體減少,預計不會產(chǎn)生跨介質(zhì)影響。
Technical considerations relevant to applicability
4.5.3.7.6 技術適用性的考慮
The technique is generally applicable to grate and rotary kiln plants.
該技術通常適用于爐排和回轉窯焚燒廠。
Economics
4.5.3.7.7 經(jīng)濟因素
Investment costs are reported to be in the range of EUR 100 000–300 000.
據(jù)報告稱,該工藝設備的投資成本范圍在10-30萬歐元。
Operating costs, including maintenance and energy costs for the conveying system and reagent costs for for boiler injection, are EUR 0.4–2.20 per tonne of waste.
運行成本,包括維護,輸送系統(tǒng)的能源消耗以及噴入鍋爐的吸收劑成本(為何沒考慮燃燒熱量損失的成本?),是0.4-2.2歐元/噸垃圾。
Avoided operating costs in the case of downstream NaHCO3 sorbent injection are EUR 0.72–
2.04 per tonne of waste.
選擇下游煙氣凈化系統(tǒng)使用小蘇打作為吸收劑的成本是0.72-2.04歐元/噸垃圾。(上面的成本應該是都用消石灰)
Driving force for implementation
4.5.3.7.8 實施動力(該技術的優(yōu)勢)
? Allowance of increased input loads of acidic pollutants in the waste.
可以焚燒酸性污染物含量更高的廢棄物。
? Reduction of boiler maintenance downtime.
減少鍋爐維護停機時間。(減少檢修頻次)
? Reduction of the occurrence of acid gas emission peaks.
減少煙氣中酸性污染峰值出現(xiàn)的概率。
? Increase of the reliability of the FGC system by adding an additional step.
增加了一個額外的步驟提高了煙氣凈化系統(tǒng)的可靠性。
?As a retrofit, the technique can provide a simple upgrade of the existing FGC unit to increase the removal rate of acidic pollutants while keeping the reagent dosage rate moderate.
作為一種技改手段,該技術可以對現(xiàn)有煙氣凈化設備提供一個簡單的升級從而增加了酸性污染物的去除率,且仍可以保持吸收劑的給料量維持在中等水平。(也就是不以增加吸收劑消耗量為代價)
Example plants
4.5.3.7.9 工廠案例
ACSM S.p.A., Como (IT) (IT02); AMSA S.p.A. Milano (IT); REA Dalmine (IT) (IT10.1/IT10.2); Silea S.p.A, Valmadrera (IT) (IT11); Tecnoborgo S.p.A., Piacenza (IT) (IT12);
ACSM S.p.A., Como(意大利);AMSA S.p.A. Milano(意大利);REA Dalmine(意大利);Silea S.p.A, Valmadrera(意大利);Tecnoborgo S.p.A., Piacenza(意大利)
Ambiente 2000 Trezzo Adda (IT); Brianza Energia Ambiente-Desio (IT) (IT03); AEM Gestioni
Cremona (IT); ACCAM S.p.A., Busto Arsizio (IT) (IT01); Ecolombardia 4 Filago (IT); Schwandorf MWI (DE); Heringen RDF plant (DE) (DE50).
Ambiente 2000 Trezzo Adda(意大利 http://termotrezzo.it/ 看了一下它的排放還行);Brianza Energia Ambiente-Desio(意大利);AEM Gestioni
Cremona(意大利);ACCAM S.p.A., Busto Arsizio(意大利);Ecolombardia 4 Filago(意大利);Schwandorf 生活垃圾焚燒廠(德國);Heringen RDF 工廠(德國)。
Reference literature
4.5.3.7.10 參考文獻
[ 99, EuLA 2015 ]
4.5.3.8 Combination of semi-wet absorber and dry injection system
4.5.3.8 半干法+干粉噴射系統(tǒng)
Description
4.5.3.8.1 說明
Combination of a semi-wet process (generally SDA) and of dry sorbent injection (DSI). The
technique is also known as the three-quarters dry system.
半干法工藝(通常為SDA)和干法吸收劑直噴工藝(DSI)相結合。該技術也被稱之為四分之三干法系統(tǒng)。
Technical description
4.5.3.8.2 技術說明
The technique consists of the injection of a dry reagent (DSI) upstream or downstream of the semi-wet reactor.
該技術包括在半干法的上游(吸收塔入口)和下游(吸收塔出口,中國多采用這種工藝)噴射干式吸收劑(DSI)的方式。
The reagent of the DSI can be hydrated lime, high-surface hydrated lime, high-porosity hydrated lime or a blend of hydrated lime and carbonaceous or mineral materials.
干式吸收劑直噴工藝所采用的吸收劑可以是消石灰,高比表面積消石灰,高孔隙率消石灰或是石灰與碳質(zhì)(礦物材料)的混合物。
The basic principle of operation is to keep the injection of milk of lime in the reactor constant at the optimal design rate to capture most of the pollutant load, while the DSI is used to remove the residual acidic gas load including peaks by means of direct regulation control.
基本操作是以最佳設計速率保持反應器中石灰漿液的注入量保持恒定,以捕獲大部分污染物負荷,而干粉噴射則通過直接調(diào)節(jié)控制來去除殘余的煙氣中的酸性負荷(包括峰值的酸性污染物)。
Achieved environmental benefits
4.5.3.8.3 獲得環(huán)境效益
?Reduction of the overall pollutant load released into air compared to a typical semi-wet process.
與典型半干法工藝相比,該工藝可以減少排放到空氣中的污染物總量。
?Reduction of the quantity of residues generated thanks to improved stoichiometry compared to reaching the same removal rate with a semi-wet process alone.
與半干法工藝相比,達到同樣的去除率,該工藝因為改進(減少)了吸收劑的化學計量比而減少了副產(chǎn)物的產(chǎn)生量。
Environmental performance and operational data
4.5.3.8.4 排放性能和運行數(shù)據(jù)
Reported removal efficiencies are > 98 % for SO2 and > 99 % for HCl.
報告稱該工藝的SO2的去除效率大于98%,HCL的去除率大于99%。
Reported advantages are:
報告稱該工藝的優(yōu)勢在于:
?constant operation of the milk of lime preparation;
石灰漿制備系統(tǒng)可以恒定運行;
?fast and accurate response of the DSI to peak pollutant loads;
干粉噴射工藝對峰值污染物負荷出現(xiàn)的反應快速而有效;
?redundancy of equipment for maintenance purposes;
從維護角度而言,多了備用設備;(就是半干法維護時候,還有干法還可以頂一下,有了備用系數(shù))
?reduction of total reagent consumption (at equal acid gas removal rate) compared to the semi-wet process alone.
與單獨使用半干法工藝相比(基于相同的酸性氣體去除率為前提),減少了吸收劑的消耗總量。
Cross-media effects
4.5.3.8.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
Since an overall reduction in the use of reagents compared to the use of SDA alone is reported at the same pollutant removal rate, no cross-media effects are expected.
報告稱,在相同的污染物去除率下,與單獨使用半干法工藝相比其吸收劑使用總量減少了,因此預計沒有跨介質(zhì)影響。
Technical considerations relevant to applicability
4.5.3.8.6 技術適用性的考慮
The technique is applicable to new plants and to existing plants using SDA as the FGC process.
該技術適用于新廠建設和使用SDA半干法煙氣凈化工藝的老廠改造。
Economics
4.5.3.8.7 經(jīng)濟因素
Investment costs are EUR 100 000–200 000 for a DSI system.
干式吸收及直噴系統(tǒng)的投資成本在10萬-20萬歐元。
Operating costs, including maintenance and energy costs for the conveying system and reagent costs (1 kg hydrated lime per tonne of waste) for DSI, are EUR 0.17–0.29 per tonne of waste.
運行成本,包括干式吸收劑直噴系統(tǒng)維護成本,輸送系統(tǒng)的能源消耗成本,吸收劑成本(噸垃圾1公斤消石灰消耗量),總計為0.17-0.29歐元噸垃圾。
Avoided operating costs by reducing reagent consumption in the SDA unit are EUR 0.33–0.38 per tonne of waste, based on reducing lime consumption from 10 kg to 7.5 kg per tonne of waste.
通過半干法+干法工藝實現(xiàn)比單獨使用半干法工藝,從而將石灰消耗量從10公斤/噸垃圾減少到7.5公斤/噸垃圾,這減少半干法系統(tǒng)的吸收劑消耗成本是0.33-0.38歐元/噸垃圾。
Driving force for implementation
4.5.3.8.8 實施動力(該技術的優(yōu)勢)
?As a retrofit, to enable a plant fitted with SDA to further reduce emission levels.
作為技改技術,可以是裝有SDA半干法工藝的焚燒廠進一步提高其污染物控制排放水平。
?Allowance of increased input loads of acidic pollutants in the waste.
可以焚燒酸性污染物含量更高的廢棄物。
?Savings in operating costs.
省下了運行成本。(應該是吸收劑達到同等脫除率時,總耗量減少。)
Example plants
4.5.3.8.9 工廠案例
Intradel Uvelia-Herstal (BE) (BE04); SNVE, Rouen (FR); BSR, Berlin (DE); IPALLE,
Thumaide (BE); Vattenfall IKW, Ruedersdorf (DE) (DE84); SWB MHKW, Bremen (DE) (DE39); SERTRID Usine de Bourgogne (FR); IBW, Virginal (BE); Amagerforbraending, Copenhagen (DK); Slagelse Forbr?ndings Anl?g, Slagelse (DK) (DK03).
Intradel Uvelia-Herstal(比利時);SNVE, Rouen(法國);BSR, Berlin(德國);IPALLE,
Thumaide (德國); Vattenfall IKW, Ruedersdorf (德國); SWB MHKW, Bremen (德國); SERTRID Usine de Bourgogne (法國); IBW, Virginal (比利時); Amagerforbraending, Copenhagen (丹麥); Slagelse Forbr?ndings Anl?g, Slagelse (丹麥).
Reference literature
4.5.3.8.10 參考文獻
[ 100, EuLA 2015 ]
4.5.3.9 Use of acid gas monitoring for FGC process optimization
4.5.3.9 酸性氣體檢測在煙氣凈化工藝中的優(yōu)化
Description
4.5.3.9.1 說明
By using fast-response HCl, SO2, and possibly also HF monitoring upstream and/or downstream of dry and semi-wet FGC systems, it is possible to adjust the operation of the FGC system so that the quantity of alkaline reagent used is optimised for the emission set point of the operation.
使用在干法或半干法煙氣凈化系統(tǒng)的上游和/或下游設置的快速反饋的HCL,SO2以及HF在線監(jiān)測信號,可以調(diào)節(jié)煙氣凈化系統(tǒng)的操作,這樣堿性吸收劑的使用量可以根據(jù)操作的設置的排放值來進行優(yōu)化(減少)。
Technical description
4.5.3.9.2 技術說明
The technique is generally applied as an additional method to control peak concentrations, with
the build-up of a layer of reagent on the bag filters also providing an important buffering effect for reagent fluctuations.
該技術通常作為一種控制峰值濃度的輔助方法使用,通過在濾袋表面形成一層濾餅同時當反應劑波動時,提供了一種重要的緩沖作用。
This technique is not relevant to wet scrubbers as the scrubbing medium is water and the supply of water to a wet scrubber is controlled by the evaporation and bleed rates, not by the raw HCl concentration. [ 64, TWG 2003 ]
該技術與濕法洗滌技術無關,因為洗滌的介質(zhì)是水,給濕法洗滌塔供水是由蒸發(fā)和排放的速率所控制的,而不是依據(jù)氯化氫的濃度。(即我們濕法領域通常所說的脫硫是靠的水洗滌煙氣中的酸性物質(zhì),而不是依靠的吸收劑的濃度多少。先用水洗下來,隨后再考吸收劑去中和。)
Just preventing HCl breakthrough is not always sufficient to ensure for all FGC systems that enough reagent is available to also provide for SO2 and/or HF control and, therefore, reduce peak emissions. [7, TWG 2017]-EuLA
僅僅防止HCl的峰值超標并不總是足以確保所有煙氣凈化系統(tǒng)有足夠的試劑可用于控制SO2和/或HF,從而減少峰值排放。
Achieved environmental benefits
4.5.3.9.3 獲得環(huán)境效益
Benefits of the technique are that:
該技術的好處是:
? peak raw gas loads are anticipated and therefore do not result in elevated emissions to air;
原煙氣的峰值(通過設置cems反饋)可以被提前得知,因此不會出現(xiàn)相應的超標排放;
? neutralisation reagent consumption can be reduced by matching the demand;
脫酸的中和劑的耗量可以通過匹配需要量來減少。
? the amount of unused reagent in residues is reduced.
副產(chǎn)物中未使用的吸收劑的數(shù)量減少。
These environmental benefits are highest where waste quality control at the input to the furnace is limited, and lower where wastes are homogenised and subjected to good-quality control by means of selection, mixing or pretreatment operations.
這些環(huán)境效益是最高的,因為入爐的垃圾質(zhì)量得到了控制,通過分選,混合或預處理操作使得垃圾均質(zhì)化,從而得到更好的品質(zhì)管理。
Smaller plants may benefit the most as rogue waste inputs can exert a larger influence on smaller throughput systems.
小型焚燒廠的得益是最大的,因為較小吞吐量的系統(tǒng)對垃圾的品質(zhì)波動影響最大。
Environmental performance and operational data
4.5.3.9.4 排放性能和運行數(shù)據(jù)
The response time of the monitor needs to be fast to pass the control signal to the reagent dosing
equipment in time to provide an effective response.
在線監(jiān)測的反饋速度要求及時快速地把信號傳輸給吸收劑給料設備,從而提供有效分反饋。
Where the monitors are located upstream of the FGC system, their resistance to corrosion is essential because of the extremely aggressive environment. Fouling can also be a problem.
當在線監(jiān)測位于煙氣凈化系統(tǒng)的上游,他們的耐腐蝕性是至關重要的,因為入口區(qū)域的環(huán)境是非常惡劣的。積灰也是一個問題。
The variation in the absorption capacity in the FGC system can be achieved by:
煙氣凈化系統(tǒng)中的吸收容量的變化可以通過以下方式實現(xiàn):
?changing the flow rate using variable speed pumps or variable speed dosing screws;
使用變頻泵或可變速給料的螺旋來改變給料量;
?changing the reagent concentration in semi-wet systems – where the mixing tank volume is small enough to ensure an adequate concentration change rate;
改變半干法系統(tǒng)的吸收漿液濃度—制備罐的容量足夠小以便確保足夠的濃度變化率;(個人理解,因為制備罐太大,導致制備完一次要等很長時間才能用完,會導致調(diào)節(jié)能力下降。)
?adjusting the ratio of the reagents in FGC systems where multiple reagents or multiple FGC
steps are used.
調(diào)整煙氣凈化系統(tǒng)中的吸收劑劑量,如果有多段煙氣凈化系統(tǒng)使用的那么調(diào)整各種對應的藥劑給料量。
Cross-media effects
4.5.3.9.5 跨介質(zhì)影響(增加的能源消耗或其他影響)
None reported.
沒有報道。
Technical considerations relevant to applicability
4.5.3.9.6 技術適用性的考慮
The technique is generally applicable.
這個技術是普遍使用的。
Economics
4.5.3.9.7 經(jīng)濟因素
No information provided.
無信息可提供
Driving force for implementation
4.5.3.9.8 實施動力(該技術的優(yōu)勢)
?As a retrofit at existing plants, to avoid exceeding short-term emission limits.
作為一種現(xiàn)有工廠的改造手段,可以解決短期排放值超標的問題。
?In the design of new plants, to optimise reagent consumption while ensuring compliance with short-term emission requirements.
在新廠設計時,在確保短期排放值(如:小時均值,半小時均值,15分鐘均值等)的同時還可以減少吸附劑的耗量。
Example plants
4.5.3.9.9 工廠案例
Applied at incinerators across the EU, e.g.Vitre (FR) (FR002); Cergy, Saint-Ouen L’Aum?ne
(FR) (FR075); MHKW Bremerhaven, Breme (DE) (DE39); MKVA Krefeld (DE) (DE55.2R); UTE-TEM, Mataró (ES) (ES04); Allington Incinerator (UK) (UK07); Lincoln (UK) (UK12).
適用于全歐盟的的焚燒廠,如:法國Vitre焚燒廠(FR002);法國Cergy焚燒廠(FR075);德國Breme焚燒廠;德國MKVA Krefeld焚燒廠;西班牙UTE-TEM焚燒廠;英國Allington焚燒廠;英國Lincoln焚燒廠;
Reference literature
4.5.3.9.10 參考文獻
[ 17, ONYX 2000 ], [ 64, TWG 2003 ]