一段英文文献的翻译The CAAA were designed to reduce SO2 and NOx air emissions. No mercury control policies from electric facilities are specified in the CAAA. Mercury emission reductions reflecting lower mercury release than available from co
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一段英文文献的翻译The CAAA were designed to reduce SO2 and NOx air emissions. No mercury control policies from electric facilities are specified in the CAAA. Mercury emission reductions reflecting lower mercury release than available from co
一段英文文献的翻译
The CAAA were designed to reduce SO2 and NOx air emissions. No mercury control policies from electric facilities are specified in the CAAA. Mercury emission reductions reflecting lower mercury release than available from coal are due to emission control technologies for other pollutants, such as SO2 and NOx, that can also incidentally capture mercury. Currently, emission control technologies are fairly broadly applied for control of
particulate, SO2, and NOx from coal-fired power plants. U.S. utilities generally employ one of two strategies to control SO2 in the flue gas stream: 1) FGD units or 2) compliance fuels.
Particulate control is typically accomplished by the use of fabric filters (also called baghouses or electrostatic precipitators [ESPs]). NOx is typically controlled through low-NOx burners, overfire, selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), or a combination of these technologies. Particulate NOx control technologies will not be discussed in this report except in relation to the issue to SO2 control. Other methods including fluidized bed
combustion (FBC) units can also control SO2. Many western coals and some eastern coals are naturally low in sulfur and can be used to meet SO2 compliance requirements. Utilities may also
physically clean or wash all or part of the fuel prior to combustion. Physical coal cleaning at the mine, transshipment point, or power plant is quite widespread in the United States not only because it reduces emissions, but also because an increase in steam generator efficiency is often possible if the fuel feedstock can be made more homogeneous. Utilities may also blend coals of different sulfur contents to achieve a mix that is in compliance with applicable regulations. Most
utilities, approximately 70%, utilize compliance fuel to achieve the SO2 emission levels currently mandated. According to the U.S. Department of Energy (DOE, 1997), FGD scrubbing unit
utilization is estimated to cost $322 per ton of SO2 removed and is the most expensive compliance method, although costs vary widely across regions. Also, according to DOE,modifying a high-sulfur bituminous coal-fired plant to burn lower-sulfur subbituminous coal is estimated to cost $113 per ton of SO2 removed and is the least expensive method. Although FGD
scrubbing units are the most expensive compliance method, FGD can be cost-effective. The type of compliance method implemented needs to be carefully evaluated for the specific coal-fired plant.
一段英文文献的翻译The CAAA were designed to reduce SO2 and NOx air emissions. No mercury control policies from electric facilities are specified in the CAAA. Mercury emission reductions reflecting lower mercury release than available from co
CAAA 被设计减少二氧化硫和氮化物空气放射.水银控制政策从电设施不被指定在CAAA .水星放射减少反射更低的水银发行比可得到从煤炭归结于排出物控制技术为其它污染物,譬如二氧化硫和氮化物,可能附带并且夺取水银.当前,排出物控制技术相当宽广地申请控制 微粒物质、二氧化硫,和氮化物从燃煤电厂.美国公共事业一般使用二个战略的当中一个控制二氧化硫在废气小河:1) FGD 单位或2) 服从燃料.属于颗粒的控制由对织品过滤器的用途典型地完成(并且叫做baghouses 或静电除尘器[ ESPs ]) .氮化物是典型地受控通过低氮化物燃烧器、overfire 、有选择性的催化作用的减少(SCR),有选择性的noncatalytic 减少(SNCR),或这些技术的组合.属于颗粒的氮化物控制技术不会被谈论在这个报告除了关于问题对二氧化硫控制.其它方法包括fluidized-bed 燃烧(FBC) 单位可能并且控制二氧化硫.许多西部煤炭和一些东部煤炭是自然地降低在硫磺,可能被使用符合二氧化硫服从要求.公共事业并且可以 清洗或完全洗涤燃料的全部或部份在燃烧之前.物理煤炭清洁在矿、转船点,或能源厂是相当普遍在美国不仅因为它减少放射,而且因为在蒸汽发电器效率的增量经常是可能的如果燃料原料可能使更加同类.公共事业也许并且混和不同的硫磺含量的煤炭达到是依从可适用的章程的混合.多数 公共事业,大约70%,运用服从燃料达到二氧化硫放射水平当前被托管.根据美国能源部(DOE 1997),FGD 洗刷的单位 运用估计花费$322 每吨二氧化硫被取消和是最昂贵的服从方法,虽然费用广泛变化横跨地区.并且,根据母鹿,修改高硫磺沥青燃煤工厂烧低硫磺subbituminous 煤炭估计花费$113 每吨二氧化硫被取消和是最少昂贵的方法.虽然FGD 洗刷的单位是最昂贵的服从方法,FGD 可能是有效的.类型服从方法实施了需要仔细地被评估为具体燃煤工厂?