Waste Incineration Plants Research Articles

ENVIRONMENTALLY SAFE OPERATION OF MUNICIPAL WASTE INCINERATION

The technology of waste incineration makes it possible to solve the issue of obtaining an alternative type of fuel and eliminate the problem of the excess waste in landfills. A multi-stage emission cleaning technology has been proposed to protect the environment and service personnel. The chemical processes that take place in the furnace space have been considered.
 The purpose of the research is to develop the concept of control systems for the technological cycle of the installation of thermal disposal of solid household waste to protection of the environment from these toxic substances: dioxins, carcinogenic hydrocarbons, products of incomplete combustion, in particular, polycyclic aromatic hydrocarbons, nitrogen and sulfur oxides. A complex of methods of system analysis and the method of data analysis was applied to achieve the goal of the research. An analysis of modern international literary sources, an analysis of the morphological composition of solid household waste, an analysis of the interaction of chemical substances, and experimental studies at a research and industrial facility were carried out. As a result of the research, the scientific and applied task of improving the system of protection of the environment and service personnel from emissions of thermal disposal of solid household waste was formulated and substantiated.
 Research results might apply to designing equipment for waste incineration, for choosing rational parameters of the furnace, location of fuel supply burners. General recommendations for the use of chemical properties of harmful substances in the design of cleaning equipment have been provided. The effectiveness of the method of supplying an inert medium (flue gases) to the combustion zone at a temperature below the flame temperature was evaluated. Effective thermal destruction of dioxins is possible in modern waste incineration plants, provided high temperatures, excess air and sufficient residence time followed by a catalytic cleaning. Homogeneous and heterogeneous formation of polychlorinated dibenzodioxins and polychlorinated dibenzofurans formed and released in zones with relatively low temperatures.

Untreated municipal solid waste incineration ashes for cement replacement

This paper characterised the two different ashes, namely Boiler Ash (BOA) and Residue Ash (RA), collected from Qatar's Municipal Solid Waste Incineration (MSWI) plant through a range of detailed analyses (chemical, physical and morphological). The potential utilisation of these raw MSWI ashes as supplementary cementitious material (SCM) in cement-based composites has been investigated by replacement with 0%, 10%, 20%, and 30% by weight of cement. The effect of the replacement levels on workability, setting time, and strength was investigated. Test results showed that setting time increased and workability decreased with the increase of BOA content. On the contrary, RA substitution decreased the setting time and increased the workability. The highest compressive strength was obtained in RA-incorporated mortars at a 10% replacement ratio. Beyond the 10% replacement ratio, RA incorporation significantly reduced the strength. Due to BOA's high unburned carbon content, BOA substitutions reduced the strength of the mortars. However, the impact of the replacement ratio was not as strong as those in RA mortars. Considering setting time, workability, and compressive strength, BOA and RA's optimum percentage of cement replacement was 20% and 10%, respectively. Heavy metal and salt leaching from MSWI ash-incorporated mortars were evaluated by the monolithic tank test. Results indicated that most toxic metals and salts, except Ba and Cl-, were stabilised in the cement matrix.

The impact of pollutant emissions from co-incineration of industrial waste in municipal solid waste incinerators

A large amount of industrial solid waste (including waste plastics, textiles, wood, etc., which are byproducts of industrial production) urgently needs to be treated. Incineration is undoubtedly the most efficient and convenient method. The existing municipal solid waste incineration plants can be transformed to burn such industrial wastes. However, the potential risks associated with high levels of heavy metals in industrial waste and the air pollution caused by co-incineration pose significant challenges to the co-incineration disposal of industrial solid waste. The change of physical and chemical properties of municipal solid waste and the emission characteristics of flue gas pollutants after co-incineration of industrial waste were studied by means of material flow simulation and experiment. In addition, experiments were designed to study the effects of temperature, calcium sulfur ratio and chlorine content on heavy metal emission during the incineration of industrial waste. The results showed that co-incineration of a certain proportion of industrial waste significantly increased the calorific value of municipal solid waste, but excessive mixing of plastic and paper industrial waste would increase the ash content. Co-incineration of plastic industrial waste can significantly increase HCl, and with the increase of temperature, the transformation of Cl to HCl is more thorough. The increase of temperature can promote the migration of Cr, Pb and Se elements to the gas phase. When Cr, Pb, and Se elements are present in the gas phase, they can combine with other gases and aerosols to form particulate matter and toxic substances, causing air pollution. When Ca/S is 1, Ba, Mn, Ni, Zn can effectively reduce the retention rate of elements in the ash. Under certain conditions, chlorine in industrial waste plastics will react with Zn to form tiny particles and low boiling point chlorides, which will increase its volatility. The mineral components in the ash can also be used for making ceramsite and building materials. These results will provide reference for the pollutants controlling during co-incineration of industrial waste and municipal solid waste process.

Characteristics of fly ash from the municipal solid waste incineration plant in Can Tho

Characteristics of fly ash from the municipal solid waste incineration plant in Can Tho

Characterization of different solid fuels from waste for an advanced online fuel control system designed for large-scale incineration plants.

Despite many years of experience in the incineration of solid fuels from waste, the heterogeneity of solid fuels and their varying properties still pose a challenge for a stable and clean combustion in large-scale incineration plants. In modern facilities such as municipal waste incineration plants there still exists a lack of knowledge on the exact amount and calorific value of waste entering onto the grate. Based on the works of Warnecke et al. and Zwiellehner et al., in our project 'AdOnFuelControl', we determined the initial bulk density at the feed hopper by measuring the weight of the waste via the crane weigher and the volume via a high-performance 3D laser scanner. With the help of the determined bulk density, the lower heating value (LHV) and the compression in the feed hopper were calculated. All this information was integrated into the combustion control system, which provided a high potential for an optimized operation of the plant. In this article, six different fuels (fresh and aged municipal solid waste, refuse-derived fuel (fluff), refuse-derived fuel (fine grain), waste wood and dried, grained sewage sludge) were examined for the elemental composition, the LHV, fuel-specific parameters and the compression behaviour. In addition, initial tests with the 3D laser scanner as well as formulas for the calculation of the density in the feed hopper were presented. Based on the results of the experiments, the chosen approach seems very promising for optimized combustion control in large-scale incineration plants. As a next step, the gained knowledge and technology should be integrated in the municipal waste incineration plant.

Material flow analysis-based assessment of polypropylene-fiber-containing microplastics released from disposable masks: Characterizing distribution in the environmental media

With the upsurge in the use of disposable masks during the coronavirus disease pandemic, improper disposal of discarded masks and their negative impact on the environment have emerged as major issues. Improperly disposed of masks release various pollutants, particularly microplastic (MP) fibers, which can harm both terrestrial and aquatic ecosystems by interfering with the nutrient cycling, plant growth, and the health and reproductive success of organisms. This study assesses the environmental distribution of polypropylene (PP)-containing MPs, generated from disposable masks, using material flow analysis (MFA). The system flowchart is designed based on the processing efficiency of various compartments in the MFA model. The highest amount of MPs (99.7 %) is found in the landfill and soil compartments. A scenario analysis reveals that waste incineration significantly reduces the amount of MP transferred to landfills. Therefore, considering cogeneration and gradually increasing the incineration treatment rate are crucial to manage the processing load of waste incineration plants and minimize the negative impact of MPs on the environment. The findings provide insights into the potential environmental exposure associated with the improper disposal of waste masks and indicate strategies for sustainable mask disposal and management.

Baseline Soil Dioxin Levels from Sites Where Municipal Solid Waste Incineration Construction Is Planned throughout China: Characteristics, Sources and Risk Assessment

The determination of baseline dioxins levels in soils is fundamental for the quantitative assessment of the net environmental and health impacts of municipal solid waste (MSW) incineration plants, which remains unexplored. Therefore, this study develops a Chinese baseline soil dioxins database (covering 918 soil samples from 292 pre-construction MSW incineration plants nationwide during 2016–2020) to thoroughly explore the baseline contamination characteristics and health risks of dioxins in soils. The empirical results show that (1) for concentration levels, the baseline international toxic equivalency (I-TEQ) concentrations vary from 0.0015 to 32 ng I-TEQ/kg, which are close to or even lower than those in most existing studies and show significant heterogeneity across provinces; (2) for dioxins homolog, highly chlorinated dioxins (i.e., PCDDs) are the dominant contributor to the total dioxins in soils (contributing 54.30% of the total I-TEQ concentrations), implying that dioxins in baseline soils often have an atmospheric fingerprint; and (3) for health risks, the carcinogenic risk and non-carcinogenic risk of dioxins in soils are mostly below acceptable levels, close to or even lower than the results of previous studies. Despite these results being considered as quite preliminary, they have certain implications for local authorities. Future studies can expand the size of the database and the generalizability of the results, and if necessary, establish a long-term dynamic monitoring of dioxins in soils for systematically evaluating the net impact of MSW incineration on environment and human health.

Buffering effect of the economizer against PCDD/Fs in flue gas from solid waste incineration plants

The emission of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from solid waste incineration is always a crucial concern for the society. Less attention has been paid to differentiate its formation and migration in the low temperature range of economizer, leading to a fuzzy understanding on the control of PCDD/Fs before flue gas cleaning. This study first reveals the buffering effect against PCDD/Fs in the economizer, which is contrary to the well-known memory effect, and first recognizes the intrinsic mechanism by 36 sets of full-scale experimental data under three typical operating conditions. Results indicated that the buffering effect, which includes interception and releasing, could remove averagely 82.9 % of PCDD/Fs in flue gas and reconcile PCDD/Fs profiles. The interception effect is dominant and in compliance with the condensation law. The low temperature range of economizer is exactly suitable for the condensation of lowly chlorinated congeners, which condense behind highly chlorinated ones. The releasing effect was non-staple but stimulated by the sudden change of operating condition, proving that PCDD/Fs formation rarely exists in the economizer. The buffering effect is mainly controlled by the physical migration of PCDD/Fs among different phases. The condensation of PCDD/Fs leads to their migration from vapor phase to aerosol and solid phases during flue gas cooling in the economizer. There is no need for excessive anxiety about PCDD/Fs formation in the economizer because it rarely exists. Intensifying the condensation process of PCDD/Fs in the economizer can help relieve the pressure of end-of-pipe measures for PCDD/Fs control.

Investigating the Potential of Biobinder for Bottom Ash Solidification/Stabilization: Leaching Behaviour and pH Dependence

Nowadays, a large amount of municipal solid waste incineration bottom ash (IBA) is produced from waste incineration plants; therefore, it is still a challenge for IBA management. To investigate the potential of microbially-induced carbonate precipitation (MICP) for IBA treatment, a harmless biobinder was prepared by using biosolutions with different bacterial concentrations. A series of tests were carried out on the sample of the IBA treated with different biosolutions, such as leaching behavior, sequential extraction, pH dependence, pore distribution, and microscopic morphology. The results showed that Zn, Cu, and Pb in the IBA after biotreatment were all below the standard limitation. In the sample with 108 cells/mL bacterial concentration, the leaching concentrations of Zn, Cu, Pb, and Cr were 0.39 mg/L, 0.12 mg/L, 0.025 mg/L, and 0.021 mg/L, respectively, and the average immobilization ratio reached 76.4%. The results of the characterization and microscopic morphology showed that biomineralization generated a large number of bioprecipitates and biogels, which formed a compact structure to reduce the pore size of samples, thus immobilizing the heavy metals. The bacteria could change the chemical speciation and bonds of the heavy metals by induction, which turned the heavy metals into stable compounds. Additionally, the lowest leaching concentration of Zn, Cu, Pb, and Cr appeared at pH of 8–10.5. This study analyzed the feasibility of bacterial concentration for IBA solidification/stabilization and provides a new biotechnology idea for IBA management.

Performance of a pilot-scale EGSB-Bardenpho process treating fresh leachate from municipal solid waste incineration plant

The fresh leachate of municipal solid waste incineration plant (FLIP) has different characteristics from that of sanitary waste landfill plant (LSL), so attention should be paid to the development of FLIP treatment technology. This study proved that EGSB-Bardenpho process with massive effluent reflux could achieve better COD and TN removals. Through the reflux, the effluent organic matter (EfOM) and dissolved organic nitrogen (DON) could be further removed, thus improving the effluent quality. The effluent reflux effectively overcame the inhibition of ammonia nitrogen, and increased the COD removal of the process by about 7.8%, which was attributed to the additional 73% removal of EfOM. The average methane yield of EGSB reactor was 309 N ml·(g COD removed) −1 but the methane production did not timely reflect the state of the reactor. The inhibition threshold of total ammonia nitrogen (TAN) and free ammonia nitrogen (FAN) on the expanded granular sludge bed (EGSB) reactor was 250–360 and 7–10 mg N·L−1, respectively. 20% of the total influent entering the Bardenpho system could provide the carbon source enough for the denitrification when the TN removal rate was about 98%. In the case of 80% of the FLIP treated by the EGSB reactor, its contribution to the total system COD removal was approximately 71%. The presence of TAN appeared to promote the formation of cocci-dominated granular sludge in EGSB reactor.

Coupling of alkaline and mechanical modified fly ash for HCl and SO2 removal in the municipal solid waste incineration plant

In this study, fly ash was modified by ball milling through coupling alkaline and mechanical to achieve the reuse of fly ash. The adsorption capacity of fly ash for acidic gases was improved in experiments using simple ball milling. Under the optimal ball milling conditions with coupled NaOH, the desulfurization efficiency can reach 100% and the dechlorination efficiency can be maintained above 90% for the first 100 s of the experiment. Different characterizations show that the ball milling process increases the specific surface area of fly ash, which makes NaOH adhere uniformly to the surface of fly ash particles in an amorphous structure and improves the adsorption effect of the fly ash on acid gases. In addition, experiments with different gas parameters proved that increased temperature, increase of the flue gas flow rate, and increase of the acidic gas concentration in flue gas all lead to the decrease of the modified fly ash’s deacidification efficiency. This provides a reference for engineering applications of modified fly ash under different working conditions. In summary, a comprehensive technical route of “fly ash collection - online modification - timely injection” is proposed in the municipal solid waste incineration (MSWI) plant.

Integration of dedusting and denitration in V2O5-WO3/TiO2/PTFE-based catalytic bag-filter materials: Lab- and pilot-scale testing and development of SCR models

Removal of dust and NOx from flue gas is highly significant for air pollution control, and integration of these two functions in one unit can greatly improve process efficiency. In this study, a functional catalytic bag-filter material (CBFM) was fabricated from commercial PTFE felt and cheap catalyst V2O5-WO3/TiO2 via a simple immersion-fixation procedure. The attachment of catalysts on PTFE was confirmed, and the material properties of CBFM of various loadings were determined. Their denitration and dedusting performances were investigated individually in lab-scale experiments. Compared to the original PTFE, CBFMs exhibited superior denitration activities, which were positively correlated with temperature (60–90% under 150–210 °C) and negatively correlated with filtration velocity (50–90% under 0.5–0.9 m min−1). On the other hand, introduction of catalysts in PTFE felt did not compromise its filtration efficiency, and almost complete dust removal was achieved. A simplified kinetic model was developed based on Eley-Rideal mechanism, to correlate the materials' denitration efficiency with various operational conditions. The model's accuracy was verified in both lab and pilot environments, where real flue gas from a waste incineration plant was treated with a scaled-up CBFM. In a six-day continuous test, the CBFM maintained >70% NO removal and >99.8% dust removal, confirming its stability and applicability in industrial settings. Therefore, this study offers a low-cost and functional bi-functional filter material capable of efficient simultaneous dedusting/denitration, as well as a simple and practical procedure for its manufacture. In addition, the kinetic model could be applied to speed up production and process optimization, and direct future application of similar materials in real environments.

Radioactivity of residues from waste incineration facilities in Finland

Waste incineration in Europe has been increasing in the past few decades as there is a need to reduce the burden on landfills and their associated environmental concerns. While incineration reduces the volume of the waste, the volume of slag and ash is still substantial. To find out potential radiation risks that incineration residues could set to workers or the public, the levels of radioactive elements in these residues were investigated from nine waste incineration plants in Finland. Natural and artificial radionuclides were detected in the residues, but in general the activity concentrations were low. This study shows that the level of Cs-137 in the fly ash from municipal waste incineration follows the pattern of 1986 fallout zones in Finland, although the levels are significantly lower than in ash from bioenergy production from the same areas. Am-241 was also detected in many samples, although the activity concentrations were very low. Based on the findings in this study, the typical ash and slag residues from municipal waste incineration do not need radiation protection measures for workers or the public even in regions that received up to 80 kBq m−2 of Cs-137 fallout in 1986. The further use of these residues need not be restricted due to radioactivity. Hazardous waste incineration residues and other special cases need to be considered separately, depending on the original waste composition.

Implementation of electrocoagulation for reduction of Zn in an outlet stream from waste incineration plant

The paper is focusing on the full-scale operation of electrocoagulation for Zn removal from wastewater with origin in a municipal incineration plant. The process was custom designed for continuous full-scale operation. Total capacity of the process varied between 1200 and 1400L/h. This was achieved by two simultaneous electrocoagulation cells operated in parallel. Residual concentrations of Zn in the treated water were consistently lower than 0.5 mg/L during the testing period. Residual concentrations of Zn and other accompanying contaminants were reduced below the desired limits (current limit for Zn in outlet water is 1.5 mg/L). The process cost was critically assessed. The electricity consumption for the operation of electrocoagulation cells is 0.75–1.1 kWh/m3 of purified water. A more significant expense is the consumption of electrode cartridges. The service life of electrode cartridges with a plate thickness of 5 mm is about 1 200 m3 of water/electrode pack, which represents a cost of around 0.6–1 EUR/m3 out of total 1.6 EUR/m3 of purified water. Waste incineration plants usually produce their own electricity therefore technologies like electrocoagulation become affordable and competitive.

In-silico analysis of atmospheric diffusion, crop planting degrading scheme, and health risk of dioxins from a domestic waste incineration plant.

Based on a domestic waste incineration power generation project, the dioxin emission from the waste incineration plant (WIP), phytoextraction and microbial degradation of dioxins, and dioxins human health risks reduction were investigated through in-silico methods. Based on the dioxins concentrations in soil (9.97×10-9-7.00×10-5ng/g) predicted by atmospheric dispersion model system and the Level-III fugacity model, planting schemes under different wind directions were designed considering the dioxin absorption capacity and the economic benefits for crops (i.e., barley, peanut, pea, maize and wheat). The dioxins in soils can be further degraded by five crops' rhizosphere microorganisms and fertilizers, simulated through molecular dynamic simulations. The enhanced degradation rates of dioxin by rhizosphere microorganisms of five crops reached 15.70%-28.66%. Finally, healthy dietary plans were developed to reduce the risk of dioxin exposure to the sensitive populations living around WIP. Results showed that the consumption of maize, fungus, mushroom and bamboo fungus could effectively reduce dioxins toxicity to humans by 58.13%. The systematic approach developed in this study provided theoretical support for soil remediation and human health risk control of dioxins-contaminated sites.

PCDD/Fs in indoor environments of residential communities around a municipal solid waste incineration plant in East China: Occurrence, sources, and cancer risks

Prolonged exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) can pose several adverse outcomes on human health. However, there is limited information on public health associated with indoor PCDD/F exposure in residential environments. Here, we examined PCDD/F concentrations in indoor air and indoor dust samples obtained from households near a municipal solid waste incineration (MSWI) plant. Our measurements revealed that the toxic equivalent (TEQ) concentrations of PCDD/Fs in indoor air ranged from 0.01 to 0.05 pg TEQ/m3, which were below intervention thresholds (0.6 pg TEQ/m3). Additionally, the TEQ concentrations of PCDD/Fs in indoor dust ranged from 0.30 to 11.56 ng TEQ/kg. Higher PCDD/F levels were found in household dust in the town of Taopu compared to those in the town of Changzheng. Principal component analysis (PCA) of PCDD/Fs suggested that waste incineration was the primary source of PCDD/Fs in indoor air, whereas PCDD/Fs in indoor dust came from multiple sources. The results of the health risk assessment showed the carcinogenic risk due to indoor PCDD/F exposure was higher for adults than for nursery children and primary school children. The carcinogenic risks of PCDD/Fs for age groups residing near the MSWI plant were all less than the risk threshold (10−5). Our findings will help to better understand the levels of PCDD/F exposure among urban populations living in residential communities around the MSWI plant and to formulate corresponding control measures to reduce probabilistic risk implications.

Causes, Types and Consequences of Municipal Waste Landfill Fires—Literature Review

The amount of municipal waste produced worldwide has seen a significant increase in recent years. The need to store waste is a significant problem in the context of environmental threats and spatial development. Due to the fact that the easiest way to reduce the amount of waste is to incinerate it, and despite the fact that waste incineration plants have existed since the late 1800s, the amount of illegal waste burning and landfills has also increased. Subsurface landfill fires are particularly dangerous, as they can affect the structure of the landfill. Methane also plays an important role in fires as it is flammable and contributes to the spread of fire. In addition, the leachate from incinerated waste is much more dangerous than the leachate from waste in its natural state. The effluents from incinerated waste include heavy metals and persistent organic pollutants, as well as sulphates, chlorides, and polycyclic aromatic hydrocarbons. Other pollutants also end up in the atmosphere. The aim of this article is to present the problem of landfill fires and their impact on air, soil, and water, based on a review of the selected documented fires as well as indicators of fires in the areas in which the authors of this article conducted their research. The article presents an overview of methods and tests, such as dynamic leaching tests, monitoring tests, and lysimetric tests, all of which can be implemented to prevent fires as well as for research purposes after a fire has occurred, so that this article can be utilitarian not only for researchers, but also for decision makers.

Differential game analysis between government and waste incineration plants on the management of municipal solid waste classification

PurposeThe purpose of this paper is to study how the government stimulates incineration plants to participate in waste classification management, and how to adjust the subsidy strategy for them.Design/methodology/approachConsidering that the classification behavior of residents will produce herd effect, and waste classification can reduce the disposal cost of incineration plants, the authors constructed a differential game model between the government and waste incineration plants, and analyzed the input strategy of the government and incineration plants when they cooperate in the management of municipal waste classification.FindingsIncreasing the input level of supervision or raising subsidy price, the government can promote incineration plants to increase the input level of incentive. Moreover, from a long-term perspective, increasing the input level of supervision is more effective. Compared with government supervision, the method of incineration plants incentive can more effectively increase the amount of waste disposal. Furthermore, the government supervision and the incineration plants incentive have a positive interaction effect on improving the amount of waste disposal. Increasing the input level of incineration plants incentive or the level of waste-to-energy technology can increase the amount of waste disposal, and from a long-term perspective, increasing the level of R&D investment is more beneficial to increasing the amount of waste disposal.Originality/valueThe results are helpful to improve the investment in the management of waste classification, and also provide a certain theoretical basis for the government's subsidy policy for incineration plants, so as to reduce the financial pressure of the government.

Perspectives on the Promotion of Solid Recovered Fuels in Taiwan

Due to the economic inefficiency of material recycling of general industrial waste and urban waste, the use of solid recovered fuels (SRFs) not only mitigates the environmental loadings from waste incineration plants and sanitary landfills but also creates green electricity and/or heat and thus reduces the use of fossil fuels. In this regard, the Taiwan government formulated the “Solid Recovered Fuel Manufacturing Guidelines and Quality Standards” in 2020 to ensure the manufacturing quality of SRFs. This paper focused on the status of waste management and energy supply, the current regulations for adopting SRFs, and the challenges in the development of SRFs from the viewpoints (or life cycle) of the environmental, economic, and engineering (or technological) characters in Taiwan. Based on the database of the official handbook/yearbook, the energy supply from indigenous biomass and waste was 1678.7 × 103 kiloliters of oil equivalent (KLOE) in 2021, which only accounted for about 1.2% of the total energy supply. Obviously, available indigenous biomass and waste for producing SRFs were mostly from waste wood, sugarcane bagasse, and mixtures containing wood/paper. Finally, some suggestions for the increasing use of SRFs in the energy and industrial sectors were addressed to keep in step with the sustainable development goals (SDGs) in 2030, especially in the mitigation of GHG emissions.

Quantitative risk assessment of occupational exposure to PCDD/Fs in the waste incineration industry

Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.