Air Pollution Control Devices Research Articles

National and provincial dioxin emissions from municipal solid waste incineration in China

China presently lacks an up-to-date regional inventory of dioxin emissions from municipal solid waste incineration (MSWI), although MSWI has grown rapidly in recent decades. Based on dioxin concentrations from the official website for governments and enterprises, we created an inventory of dioxin emissions from 29 areas in mainland China. MSWI released a total of 22.56 g I-TEQ of dioxins in 2020. According to Monte Carlo simulation, the dioxin emissions with 95 %, 75 %, and 50 % certainty are 17.03–31.62, 19.24–27.71, and 20.43–25.96 g I-TEQ, respectively. Notably, Guangdong, Zhejiang, and Jiangsu provinces accounted for 38.8 %. The primary regions with considerable dioxin emission per capita and density are Zhejiang and Shanghai. Furthermore, Jilin and Heilongjiang provinces are the top two regions in terms of dioxin emissions per unit of billion gross domestic product. These indicators were affected significantly by the quantity of MSW generated and incinerated (MSWGI), capacity and operating years of incinerators, and degrees of air pollution control devices (APCDs). Dioxin emission factors (EFs) were about 100 times lower in 2020 than in 2004. Note, however, that there is a gap in dioxin EFs between China and European nations. We have proposed that MSW source classification, stable operation conditions of incinerators and APCDs, categories of incinerators selection, and technological upgrading should be China's major measures to curb dioxin emissions. Moreover, with the future increment in the quantity of MSWGI, it is essential to completely reinvent the dioxin monitoring program.

Particulate PCDD/F size distribution and potential deposition in respiratory system from a hazardous waste thermal treatment process

The particulate polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) of various sizes produced from the waste incinerators might have different toxicities, deposition characteristics, and potential health effects in the respiratory system, and their total toxicity equivalent (TEQ) concentration has been strictly regulated in recent years. There is a knowledge gap on the effects of air pollution control devices on particle size distributions (PSDs) of PCDD/Fs and their TEQ deposition. A hazardous waste thermal treatment plant equipped with an advanced scrubber, a cyclone demister, and activated carbon adsorption coupled with a baghouse filtration was investigated in this study. An 8-stage impactor was used to collect the particle distribution of PM10 and bounded PCDD/Fs from the gas stream at four sampling points located before and after each control unit. A “TEQDE” index is defined for the toxicity deposition of PM10-PCDD/F in the respiratory system. The advanced scrubbers significantly reduced the PM10-PCDD/F levels, especially for those with sizes ≥0.6 and ≤ 0.4 μm. Additionally, the cyclone also showed a better performance than the general dry gas treatment but had an efficiency drop with 1.5–4 μm particles. The PM10-PCDD/F loads in the final adsorption-filtration unit were eased and effectively removed the PM10-PCDD/Fs to sizes ≤0.5 or≥1.5 μm. The total TEQDE was 0.00052 ng WHO-TEQ Nm−3 and had a peak level of 0.000157 ng WHO-TEQ Nm−3 at 1.2 μm. PSDs were more sensitive to the PSDs of PM mass at high PM levels but strongly correlated with the PSDs of “PM10-PCDD/Fs/PM10” at low PM10 loads. Consequently, the advanced control system could effectively remove the PM10-PCDD/Fs and might extend the adsorption-filtration lifetime. However, the PM10-PCDD/Fs ≤ 0.4 μm had a higher TEQ deposition rate and should be further considered in emissions and ambient air quality evaluations.

Emission characteristics of filterable particulate matter and condensable particulate matter from coal-fired power plants

Particulate matter (PM) emission has been widely concerned all over the world. The formation of condensable particulate matter (CPM) was affected by atmospheric temperature. An optimal-designed sampling device and monitoring method for particulate matter in high-humidity flue gas were applied to the particulate matter emission concentration of 12 ultra-low emission coal-fired units. The emission levels and composition characteristics of particulate matter and main inorganic ions in the flue gas were analyzed and evaluated. The results showed that the filterable particulate matter (FPM) concentration range was 0.81–7.52 mg/m 3 , and the condensable particulate matter concentration range was 1.10–12.25 mg/m 3 . The emission characteristics of CPM/FPM was significantly affected by different air pollution control devices. Preferable emission reduction result of condensable particulate matter may be realized by units equipping wet limestone-gypsum flue gas desulfurization and wet electrostatic precipitator. The certain correlation was showed between CPM/FPM and ash content. The inorganic ion concentration range was 1104–8240 μg/m 3 in condensable particulate matter. Ca 2+ concentration accounted for more than 45% of the cation concentration, and SO 4 2− concentration accounted for up to 97.81% of the anion concentration in CPM.

A typical 300 MW ultralow emission coal-fired power plant: source, distribution, emission, and control of polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are one of the dominant contributors to toxic organic pollutants emitted from coal combustion. In this study, the PAHs and condensable particulate matter (CPM) were sampled from a 300 MW ultralow emission coal-fired power plant. The effect of air pollution control devices (APCDs) on PAHs migration regularity and the influence of coal species changes on the emission of PAHs were studied. Note that the APCDs have definite selectivity for the removal of PAHs with different phases and ring numbers. The low-low temperature electrostatic precipitator (LLT-ESP) presented the best removal effect on PAHs (PAHs in flue gas, 29.92%; PAHs in CPM, 94.76%). The concentrations of PAHs were reduced at the outlet of the furnace (PAHs in flue gas, decreased from 3.318 to 2.850 μg/Nm3) and at the stack (PAHs in flue gas, decreased from 4.737 to 3.008 μg/Nm3; PAHs in CPM, decreased from 0.554 to 0.429 μg/Nm3) by replacing bituminous coal with blended coal (lower volatiles) as fuel. The adsorbent injection coupled with LLT-ESP had a preferable removal effect on the PAHs (decreased from 4.949 to 1.451 μg/Nm3), which was nearly 40% higher than the efficiency without the spray adsorbent.

Utilization of municipal solid waste into electricity energy: A performance of PLTSa Bantargebang pilot project

Municipal solid waste (MSW) has become a serious problem for cities in Indonesia. The increasing population and economic activity as well as the increasing difficulty in obtaining land for landfills are the real problems faced. Waste generation from urban areas currently reaches 29.4 million tons annually and that has been managed reaches 62.29%. The Indonesian government has targeted 100% waste management by 2025 by processing 70% and reducing it by 30%. To accelerate the achievement of this target, Presidential Regulation No. 35/2018 concerning installation construction acceleration of waste processing into electricity energy based on environmentally friendly technology has been issued. MSW in Indonesia contains 62.4% of biomass in the form of food waste, wood, vegetables and fruits which have the potential to be a source of energy. This paper describes the performance of PLTSa Bantargebang based on operating data in 2020. PLTSa Bantargebang was designed to be able to burn 100 tonnes of waste/day with an average calorific value of 1,500 kcal/kg and an electricity output of 700 kW. This plant was also equipped with a pre-treatment plant to reduce water content and air pollution control devices that can emit exhaust that met national emission standards. When this study was conducted, the WtE plant electricity production was around 350 kW which was only used for the internal operational needs of the WtE plant. In this condition, the WtE plant burns waste on average 65 tons waste per day. During 2020, the plant had burned 9,878 tonnes of waste by generating electricity of 784 MWh or an electricity conversion rate of 110.66 kWh/ton waste. Both exhaust gas emission and liquid waste have met national quality standards, so that it is an environmentally friendly WtE plant. The plant also produced fly ash and bottom ash around 19.41% of the weight of the waste burned.

Electricity Generated by Waste Material

This paper introduce the future sustainability, there is great concern for the steady supply of affordable, renewable and clean energy sources with minimum societal and environment damage. To meet growing energy demands, solid waste is a great hope among the available renewable energy source. Inflammation dominates the waste-to-energy (WTE) market all over the world, and specifically in developed countries. After thermal processes, without oxygen digestion is the arising technology in clean energy production. Incineration in one of the thermal processes with low environmental impact and reduces the waste volume to be dumped in landfills. For the evaluation for the environmental impact of WTE technology, life-cycle asessement help to find suitable option for a particular region. Reduction of greenhouse gas emission and generation of alternatives to fossil fuel are major goal of Waste to Energy. Moreover the development of compact, cost-saving, yet highly efficient technology required, with the best solution for the disposal/utilization of filter ashes and residues from air pollution control devices.

Curbing dioxin emissions from municipal solid waste incineration: China's action and global share

China generates the world's second-largest amount of municipal solid waste (MSW) and incinerates the largest quantity of MSW. However, data on the latest dioxin emissions from MSW incineration (MSWI) and the related global share were lacking. In the context of MSW classification, distinguishing the long-term MSW generation and incineration quantity, and dioxin emissions was necessary for macro-control and policy-making by the Chinese Government. By considering population size and GDP per capita, China's MSW generation toward 2050 was projected based on Monte Carlo simulation. Moreover, dioxin emission factors were also assumed based on the diffusion rate of four grades of air pollution control devices (APCDs). Finally, we show that the quantity of China's MSW generation in 2050 will be 363.50 million tonnes (Mt) with 341.06–382.45 Mt of 75% certainty. China's dioxin emissions from MSWI were approximately 15.46 g I-TEQ in 2019, which accounted for 26.1% of total emissions from global MSWI. We discuss dioxin emission reduction scenarios depending on MSW diversion and APCD upgrades. China's dioxin emissions will be 70.38 g I-TEQ for the business-as-usual scenario, and the dioxin emissions will be 9.29 g I-TEQ (within the range of 8.88–9.64 g I-TEQ) for the optimal scenario in 2050. Moreover, in 2050, the APCD diffusion rate will account for 98.8% of the sensitivity of dioxin emissions from China's MSWI. According to the assumed scenarios, there is a dioxin emission reduction potential of 18.6% and 86.8% in 2050 by MSW diversion alone and maximum APCD upgrades combined with food waste diversion, respectively.

Distribution and emission characteristics of filterable and condensable particulate matter in the flue gas emitted from an ultra-low emission coal-fired power plant

Total particulate matter emitted from coal-fired power plants can be classified into filterable particulate matter (FPM) and condensable particulate matter (CPM). In this study, the FPM and CPM in the flue gas were sampled from a 300 MW ultra-low emission coal-fired power plant by the simultaneous sampling system, which was conducted according to ISO 23210-2009 and U.S. EPA method 202. The results show that the emission concentration of CPM rose from 5.15 mg/Nm3 to 7.19 mg/Nm3 at the stack when coal mixed with sludge. Almost all of the air pollutant control devices have a positive effect on the removal of CPM and FPM in the flue gas, except the influence of the selective catalytic reduction (SCR) denitration device on CPM. And the SCR denitration equipment increased the concentration of inorganic components of CPM in flue gas. The low-low temperature electrostatic precipitator had the most obvious removal effect on CPM and FPM, and the removal efficiency for FPM and CPM was more than 90% and 75% respectively. The organic fraction in CPM was mainly composed of hydrocarbons, esters, organosilicon, and other organics. In particular, the proportion of hydrocarbons and organosilicon was relatively high. In the case of co-combustion of sludge and coal, the concentration of CPM and FPM in flue gas increased as a whole, but the distribution trend of CPM and FPM was consistent with that of the non-combustion sludge and the distribution of organic components in CPM was almost the same.

Study on the condensable particulate matter removal characteristics of air pollution control devices in a Chinese ultra-low emission coal-fired generating unit

Condensable particulate matter (CPM) belongs to PM25. In addition, it is one of PM2.5 main contributors. But CPM emissions are often overlooked in coal-fired power plants. As a result, this paper studies the removal characteristics of (CPM) from air pollution control devices (APCDs) in a Chinese ultra-low emission coal-fired generating unit. The quality and content of flue gas particles, including CPM and filterable particulate matter (FPM), were measured at four points: the selective catalytic reduction (SCR) input, air preheater (APH) inlet, electric precipitator (ESP) outlet, and wet flue gas desulphurization (WFGD) outlet. The removal characteristics of each APCD were studied. Within the scope of this study, it is found that: ® CPM emission concentration accounts for 94.9% of total particle emission concentration, and is higher than the ultra-low particulate matter outflow guidelines for coal-fired power plants in China; ©WFGD has the highest CPM inorganic component removal radio of 97.02%, and ESP has the highest CPM organic component removal radio of 58.46%, among APCDs; ©SO4 2−, NH4 +, F−, and Cl− are the most abundant water-soluble ions in CPM.

Differentiated emission control strategy based on comprehensive evaluation of multi-media pollution: Case of mercury emission control

In order to comprehensively evaluate the environmental impact of multi-media mercury pollution under differentiated emission control strategies in China, a literature review and case studies were carried out. Increased human exposure to methylmercury was assessed through the dietary intake of residents in areas surrounding a typical coal-fired power plant and a zinc (Zn) smelter, located either on acid soil with paddy growth in southern China, or on alkaline soil with wheat growth in northern China. Combined with knowledge on speciated mercury in flue gas and the fate of mercury in the wastewater or solid waste of the typical emitters applying different air pollution control devices, a simplified model was developed by estimating the incremental daily intake of methylmercury from both local and global pollution. Results indicated that air pollution control for coal-fired power plants and Zn smelters can greatly reduce health risks from mercury pollution, mainly through a reduction in global methylmercury exposure, but could unfortunately induce local methylmercury exposure by transferring more mercury from flue gas to wastewater or solid waste, then contaminating surrounding soil, and thus increasing dietary intake via crops. Therefore, tightening air emission control is conducive to reducing the comprehensive health risk, while the environmental equity between local and global pollution control should be fully considered. Rice in the south tends to have higher bioconcentration factors than wheat in the north, implying the great importance of strengthening local pollution control in the south, especially for Zn smelters with higher contribution to local pollution.

Suggestion on further strengthening ultra-low emission standards for PM emission from coal-fired power plants in China

China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants (CFPPs) to achieve ultra-low emission. The potential for further particulate matter (PM) emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue. In this study, PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed. The results revealed that the average filterable particulate matter (FPM) concentration, measured as the total particulate matter (TPM) according to the current national monitoring standard, was (1.67±0.86) mg/m3, which could fully achieve the ultra-low emission standard for key regions (5 mg/m3), but that achieving the near-zero emission standard was difficult (1 mg/m3). However, the condensable particulate matter (CPM), with an average concentration of (1.06±1.28) mg/m3, was generally ignored during monitoring, which led to about 38.7% underestimation of the TPM. Even considering both FPM and CPM, the TPM emission from current CFPPs would contribute to less than 5% of atmospheric PM2.5 concentrations in the key cities and regions in China. Therefore, further reduction in FPM emission proposed by the near-zero emission plan of CFPPs may have less environmental benefit than emission control of other anthropogenic sources. However, it is suggested that the management of CPM emission should be strengthened, and a national standard for CPM emission monitoring based on the indirect dilution method should be established for CFPPs. Those measurements are helpful for optimal operation of air pollutant control devices and continuously promoting further emission reduction.

A comprehensive emission inventory of hazardous air pollutants from municipal solid waste incineration in China

The Hazardous air pollutants (HAPs) released from increasing municipal solid waste incineration (MSWI) plants have drawn great concerns in China. However, a full picture of their emission characteristics is still urgently needed, especially after the implementation of stricter emission limits on MSWI. In this study, a comprehensive historical emission inventory of HAPs emitted from MSWI plants in China during the period of 2006–2017 was dedicatedly established by integrating with detailed plant-level activity data and renewed localized emission factors. Overall, HAPs emissions initially increased with years, then peaked or slowed increase in the year 2014, but leveled off after 2016 due to the gradually and fully implementing of newly revised national emission standard (GB18485–2014) applied to mainland China and much stricter local standards for several provinces and cities. It was estimated that totally 50,716 tons (t) of NOx, 13,026 t of CO, 7988 t of SO2, 4399 t of PM, 1943 t of HCl, 9916 kg of Pb, 5901 kg of Mn, 4805 kg of Cu, 3574 kg of Cr, 3329 kg of Ni, 2154 kg of Hg, 1168 kg of Cd, 862 kg of As, 409 kg of Co, 216 kg of Sb, 13 kg of Tl, and 19 g toxic equivalent quantity of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans were emitted from 337 MSWI plants scattered in 30 provinces of mainland China in 2017, respectively. HAPs emissions were heavily concentrated in developed coastal provinces and cities. Scenario analysis highlighted the importance of continuous improvement and upgrade on advanced air pollution control devices and MSWI management to meet the future ultra-low emission limits and minimize the harmful impacts of HAPs on atmospheric environment and public health.

The co-benefits of clean air and low-carbon policies on heavy metal emission reductions from coal-fired power plants in china

China has implemented a series of measures to address air pollutants and carbon emissions from coal-fired power plants, which can mitigate toxic heavy metal emissions simultaneously. By integrating plant-level information and energy activity data, we investigated the co-benefits of clean air and low-carbon policies by compiling a detailed inventory of historical heavy mental emissions (i.e., Hg, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu, Zn, As, and Se) for China's coal-fired power plants during 2005–2020. Several scenarios were then designed to assess the evolution of heavy metal emissions for each coal-fired power plant with consideration given to the coal washing rate, air pollution control devices, operational hours and lifetime. The total emissions decreased from 12.9 thousand tons in 2005 to 8.8 thousand tons in 2020, which was mainly due to the widely installation of upgraded end-of-pipe devices and the decommissioning of small and emission-intensive plants, especially in Sichuan, Jiangsu and Zhejiang. Scenario analysis shows that reducing the operational lifetime to 20 years is the most effective measure to reduce national HM emissions, but the effects differ widely between regions. This study provides insights for the precise co-control of both heavy metals and carbon emissions, which is highly important for meeting the requirements of the Minamata Convention and carbon neutrality.

Synergistic Removal Effects of Ultralow Emission Air Pollution Control Devices on Trace Elements in a Coal-Fired Power Plant

Synergistic Removal Effects of Ultralow Emission Air Pollution Control Devices on Trace Elements in a Coal-Fired Power Plant

Incineration of medical waste: Emission of pollutants into the environment

Medical waste incinerator is a matter of concern for the environment and public health due to secondary pollutants. The present work aims to evaluate the toxic emissions from medical waste incineration, such as Polychlorinated Dibenzo-Dioxin/Furan (PCDD/Fs), Polycyclic Aromatic Hydrocarbons (PAHs), and the inorganic components in ambient air and ash. Hence, this study discusses several strategies to reduce emissions. For this purpose, searches were done in Scopus, Web of Science, and PubMed databases from 2000 to 2020. After the search, screening was done according to the predefined criteria, 96 papers were finally selected for this study. The results show that the emissions levels depend on many factors like the composition of the feeding, waste type, waste classification, segregation practice, types of incinerators, operation conditions (designed temperature, retention time, and excess oxygen), and air pollution control devices. For instance, emissions of Medical Waste Incinerators (MWIs) rise sharply with a decrease in temperature, increase in oxygen levels and chlorine content in waste, and the absence or weak function of air pollution control systems. This review prepared a comprehensive detailed for decision-makers to help them to understand the environmental consequences of using incinerators. However, there is a gap in finding efficient methods to reduce emissions of incinerators.

Impacts of Removal Compensation Effect on the Mercury Emission Inventories for Nonferrous Metal (Zinc, Lead, and Copper) Smelting in China.

Nonferrous metal smelting (NFMS) is one of the key sources of mercury (Hg) emissions to the air and cross-media Hg transfer in China. In this study, a "Hg removal compensation effect" between upstream and downstream air pollution control devices (APCDs) in NFMS was uncovered based on the investigation of field test data. The relationships between the Hg concentration in flue gas and the Hg removal efficiencies of typical APCDs were established, and an advanced probabilistic mass flow model regarding this effect was developed. Model comparison shows that the probabilistic essence of the advanced model prevents the underestimation of the deterministic model caused by using the geometric means of the Hg contents of metal concentrates, and the consideration of the removal compensation effect leads to more accurate estimation of the overall Hg removal efficiency of cascaded APCDs. The Hg emission abatement in the NFMS sector from 2010 to 2017 was evaluated to be 55.6 t, which was 13.5% higher than the estimate without considering the Hg removal compensation effect. The overall uncertainty of the improved model was reduced. This study provides a new methodology for more accurate evaluation of the effectiveness of the national implementation plan for the Minamata Convention on Mercury.

Arsenic emission and distribution characteristics in the ultra-low emission coal-fired power plant.

The characteristics of arsenic emission and distribution of a typical Chinese coal-fired power plant renovated with ultra-low emission technique have been studied. The results showed that arsenic concentration in coal was 5.72 mg/kg, and the arsenic emissions in fly ash, bottom ash, gypsum, flue gas, and wastewater were 489.12 g/h, 5.15 g/h, 1.14 g/h, 0.46 g/h, and 0.03 g/h, respectively, corresponding to the proportion of arsenic in fly ash, bottom ash, gypsum, flue gas, and wastewater of 98.63%, 1.04%, 0.23%, 0.09%, and 0.01%, respectively. About 87.61% of the gaseous arsenic was absorbed by catalysts used for selective catalytic reduction (SCR). Low-low temperature electrostatic precipitator (LLT-ESP) plays a key role in decreasing particulate arsenic. Wet flue gas desulfurization (WFGD) has positive effects on absorbing both gaseous and particulate arsenic. The removal efficiencies across the air pollution control devices follow the order of LLT-ESP > WFGD > SCR. The LLT-ESP can achieve a significant arsenic removal efficiency of 99.94%, resulting in quite low arsenic emission to the atmosphere. According to the calculated arsenic emission factor, the total emission amount of arsenic to the atmosphere from all Chinese coal-fired stations with ultra-low emission control technique in 2020 is estimated to be about 9.67-11.59 tons/year.

Increasing mercury risk of fly ash generated from coal-fired power plants in China

The trend in mercury (Hg) content of fly ash, the primary solid Hg waste from coal-fired power plants (CFPPs), has not been well evaluated in China. This study integrated a national sampling campaign, a literature survey, and model predictions to investigate the trend in Hg content of fly ash and associated output nationwide. The results demonstrated that Hg content of fly ash from both our campaign conducted in 2020 and the literature survey met the Weibull distribution. The best estimate for the distribution of Hg content in our campaign (401.4 µg/kg) was about two-fold higher than that from the literature survey (236.6 µg/kg). The increasing trend was mainly attributed to the increasing installation of advanced air pollution control devices (APCDs) in CFPPs. The total national Hg output by fly ash was estimated to be 217.7 tons (64.1−501.8 tons) currently. Regarding the disposal of fly ash, a total of 16.1 tons and 105.8 tons of Hg were re-emitted into the air and immobilized in materials, respectively. The increasing trend in the Hg content of fly ash suggested the need for more stringent requirements for the disposal of solid Hg waste from CFPPs in China.

Study on the removal characteristics of different air pollution control devices for condensable particulate matter in coal-fired power plants.

This study reports the emissions of condensable particulate matter (CPM) and filterable particulate matter (FPM) in two coal-fired power plants with different air pollution control devices (APCDs). The mechanisms of CPM removed by existing APCDs in coal-fired power plants were explored, and a series of analyses were also carried out on the composition and characteristics of CPM. The results show that the removal efficiencies to CPM by electrostatic-bag-precipitator (EBP) and ESP are 77.34% and 79.23%, respectively, so the difference is not obvious because the interception filtration mechanisms of baghouses for CPM have less effect on CPM compared to FPM. The mechanism of EBP/ESP to remove CPM is mainly electrostatic adsorption and FPM's adsorption. The concentration of CPM decreases when passing through WFGD. However, the WESP can increase the CPM in different ways. For example, the pollution of the circulation of the flushing fluid may cause the increase of CPM. In addition, CPM mainly includes three parts. The first part is organic fractions such as alkanes and esters; the second is the water-soluble ions that include SO42-, NH4+, and Cl-; and the third is Na, Ca, and other minerals. The research in this study is helpful to understand the impact of existing APCDs in coal-fired power plants on CPM and the sources of CPM.

Field Studies on the Removal Characteristics of Particulate Matter and SOx in Ultra-Low Emission Coal-Fired Power Plant

In order to reduce the environmental smog caused by coal combustion, air pollution control devices have been widely used in coal-fired power plants, especially of wet flue gas desulfurization (WFGD) and wet electrostatic precipitator (WESP). In this work, particulate matter with aerodynamic diameter less than 10 μm (PM10) and sulfur oxides (SOx) have been studied in a coal-fired power plant. The plant is equipped with selective catalytic reduction, electrostatic precipitator, WFGD, WESP. The results show that the PM10 removal efficiencies in WFGD and WESP are 54.34% and 50.39%, respectively, and the overall removal efficiency is 77.35%. WFGD and WESP have effects on the particle size distribution. After WFGD, the peak of particles shifts from 1.62 to 0.95 μm, and the mass concentration of fine particles with aerodynamic diameter less than 0.61 μm increases. After WESP, the peak of particle size shifts from 0.95 to 1.61 μm. The differences are due to the agglomeration and growth of small particles. The SO3 mass concentration increases after SCR, but WFGD has a great influence on SOx with the efficiency of 96.56%. WESP can remove SOx, but the efficiency is 20.91%. The final emission factors of SO2, SO3, PM1, PM2.5 and PM10 are 0.1597, 0.0450, 0.0154, 0.0267 and 0.0215 (kg · t−1), respectively. Compared with the research results without ultra-low emission retrofit, the emission factors are reduced by 1~2 orders of magnitude, and the emission control level of air pollutants is greatly improved.