《垃圾焚烧厂最佳可用技术参考文件》2018年版 4.5章 第一部分（待续） 学习笔记（一）

•reduction of emissions by primary methods;

减少污染物排放使用的主要工艺手段；

•noise;

噪音；

•arrangement of different flue-gas cleaning devices if possible with decreasing flue-gas temperatures from boiler to stack.

规划不同的烟气工艺装置，尽可能地减少烟囱排烟温度；（从尾气中尽可能多地获取能量）

[ 74, TWG 2004 ]

4.5.1.2 Energy optimization

4.5.1.2 能源优化

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:

一些烟气净化技术可以显著增加焚烧工艺的能源需求（消耗更多能源）。在有些低排放应用是必须要消耗更多能源的。关键点如下：

•Reducing dust emissions including boiler ash (and metals filtered with dust) generally requires additional filtration and increases energy consumption.

减少粉尘排放包括锅炉灰（以及粉尘中的金属过滤）通常会需要额外的过滤装置，从而增加能源消耗。

•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.

减少NOx的排放至100mg/Nm3以下，通常使用SCR是比较适宜的。但是催化剂比较敏感容易受到污染和酸腐蚀的影响，其通常在垃圾焚烧中在低尘区域使用，布置于烟气净化系统的尾部。因此，通常需要额外的能源来对烟气进行再加热。如果原烟气中的Sox水平很低则可以允许SCR系统不进行在加热（详见2.5.5.2.2章节）。要实现额外的烟气净化目的（达到超低排放水平）所需要的能源将会使垃圾焚烧所产生的本来可以对外输出的能源进一步被消耗，或者消耗外部提供的等量的能源。虽然不常见，但是高尘布置的SCR在某些垃圾焚烧厂中也有使用。

•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.

锅炉出口温度是决定烟气净化系统能源需求的主要决定因素，为了加热烟气使他不低于酸露点就需要消耗额外的能源。

•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 ]

通常来说，在布置烟气净化各工艺段时，应当将那些最高运行温度的工艺段优先布置在那些低运行温度的工艺段上游，这样可以获得较低的能源需求（但是这个不可能在任何情况下都能实现，如：SCR通常需要布置在干净烟气区域，而导致需要布置在温度较低的净烟气段，布置在高尘段可以避免消耗能源去对烟气再热，但容易面临烟气中污染物组分对催化剂寿命影响的挑战）

4.5.1.3 Overall optimisation and the ‘whole system’ approach

4.5.1.3 整体优化及“全系统”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:

基于能源因素的考虑（看上述能源章节），将烟气净化系统作为一个整体考虑是非常必要的，因为不同工艺段之间经常会相互影响，从而与实现最终的去除污染物的目的密切相关。（Sox高了会影响SCR的催化剂，从而影响寿命。预除尘效率过高会造成酸露点偏高从而影响系统的稳定性。HCL如果太低，会导致Sox在150度左右的脱除效率等等，很多密切相关的因素）基于在烟气净化系统中的不同位置布置，会获得不同的去除效率。多用途装置非常常见，包括如下：（如：布袋有除尘功能，还有二次脱酸功能。）

•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 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.

如果布袋除尘器被用于干粉喷射的下游，除了作为一个除尘装置外，它还将成为一个二次脱酸的反应器。通过滤料纤维的压降会将烟气分配到滤饼上与存留的反应剂进行接触，由于除尘器中的气体流速较低，会因此获得一个较长的停留时间。因此，除尘器有助于去除酸性气体，气态金属类如汞和镉以及POPs（持续性有机污染物）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.

除了脱酸功能外，湿法洗涤塔对粉尘捕捉也有一定功效，如果PH值够低或使用一些洗涤剂还能脱汞。（ 在脱硫液中加入Fenton试剂可以促进单质汞氧化为二价氧化态汞，从而被脱硫液吸收，提高WFGD的脱汞效率。Lu和Tan等针对利用Fenton反应促进汞的脱除分别进行了实验室规模和中试规模的试验，试验发现，脱硫液中加入Fenton试剂时，实验室试验中，当H2O2质量分数为0.02%左右、Fe3+质量分数约为0.01%、pH为1.0～3.0条件下，烟气中单质汞的氧化率可达到75%；而中试试验中也能达到30%～40%的单质汞氧化率。）

• SCR de-NOX has an additional destruction effect on dioxins if designed (sized) accordingly.

SCR脱硝装置如果设计得当，还有一个额外功能，就是能破坏二噁英的能力。

•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）吸附工艺能去除二噁英，汞和其他物质。

4.5.1.4 Technique ion for new or existing installations

4.5.1.4 新设备或现有设备的技术选择

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.

烟气净化系统各工艺段（包括焚烧工艺的其余部分）的整体优化和内部接口对新上或现有设备来说都是同样重要的。重视现有的设备比新设设备更重要，有关工艺可以在其他章节找到。