As an important part of municipal supporting facilities, the ‘NIMBY effect’ of domestic waste transfer stations has always been the focus of attention. The fully underground domestic waste transfer station has gradually been favored by engineering designers because its production facilities are all arranged below the ground, which can effectively reduce the negative impact of waste compression treatment process. The design points of the underground domestic waste transfer station were analyzed, mainly including fire compartmentalization and functional layout, ramp design and traffic organization, smoke control and deodorization system, odor control and safe production, landscape greening and sponge storage. When dividing fire zones, it should be kept the same dividing range of fire zones and functional zones. In the design of underground ramps, it is necessary to consider the requirements of clear height, turning radius and slope required by sanitation vehicles. In terms of underground production and operation space, there are both fire protection and smoke emission requirements as well as deodorization requirements,both types of air ducts have large sizes, which need to be considered comprehensively during the design process. Safe production has always been the focus of the operation of environmental sanitation facilities, especially in the underground space. In the engineering design, it is necessary to select the appropriate process and configure toxic and harmful gas detectors to improve production safety. One of the outstanding advantages of the fully underground transfer station is that the above-ground space can be turned into an open park through the reasonable layout of landscape greening, changing the inherent impression of traditional transfer stations in people’s minds. This study was expected to provide ideas and references for the design of similar projects in the future.

Under the vision of global sustainable development, the abandoned sandy soil produced in the process of water conservancy construction needs to be improved because of its loose structure, low compressibility and high permeability, so as to promote the construction of ecological civilization and the sustainable utilization of land resources. High-performance curing agent was prepared by solid waste-based sulfur-aluminum-iron cementitious materials, gypsum and granulated high-alumina slag, and the effects of additives such as glass fiber powder, carbon nanotubes, resin rubber powder and oil sludge residue were explored. The results showed that after adding cementitious materials and additives, the maximum unit volume mass of solidified soil increased, and the strength of solidified soil increased to 10.7 to 18.1 times that of natural sandy soil, which met the strength requirements of secondary highway subbase. In addition, the impermeability of solidified soil had excellent performance, especially the combination of oil sludge residue and cementitious materials, and its 7 d permeability coefficient was reduced by 25% compared with that of simple cementitious materials solidified soil. XRD and SEM analysis revealed that ettringite and hydrated calcium silicate gel were the main filling and cementing components. Admixtures could improve the properties of solidified soil through mechanisms such as accelerated hydration of carbon nanotubes, reinforcement of glass fiber powder, bonding of resin powder and filling and bonding of oil sludge residue. This study not only provides a method for the efficient utilization of sand in the construction field, but also opens up a new way for the resource utilization of solid waste such as pyrolysis residue of oil sludge.

To investigate the techno-economic performance of solid recovered fuel (SRF) production from municipal solid waste (MSW) in China’s county regions, three short-flow SRF preparation processes，namely mechanical sorting, bio-drying, high pressure extrusion and bio-drying, were examined. Considering the characteristics of SRF production, the techno-economic performance of these processes was assessed in terms of investment, internal rate of return, economic transportation radius, and non-subsidized income proportion. Techno-economic analysis of MSW incineration was also carried out for comparison. Additionally, by integrating the four techno-economic indicators above, a comprehensive techno-economic index (CTE) was developed to evaluate the overall techno-economic performance of three SRF preparation processes. The result indicated that the production of SRF could increase power generation revenue, reduce transportation costs, and increase the net income of MSW incineration. The net income (in tons MSW) of the SRF preparation process ranged from 19.1 to 35.9 yuan, which was considerably higher than the 4.8 yuan for MSW incineration. When the MSW disposal allowance was 70.0 yuan/t, the biological drying process had the largest economic transportation radius of 90.9 km, which was 71.0% greater than that of MSW incineration. This significantly expanded the service scope of incineration plants, and was benefit to improve the MSW incineration rate in remote areas, resulting better environmental and economic benefits. Among the three SRF preparation processes, the bio-drying process exhibits the most favorable comprehensive techno-economic performance, followed by high pressure extrusion and bio-drying, and mechanical sorting.

In order to study the cross flow filtration performance of disk ceramic membrane from different sludge, a dynamic filtration device with an average ceramic disc aperture of 2 μm was adopted to conduct experiments on thermal hydrolyzed sludge, digested sludge, and AO sludge. The impact of sludge with different properties on filtration permeation flux, the filtered concentrated liquid and clear liquid were investigated. The results indicated that under the operating conditions of normal temperature feeding, a membrane rotation speed of 900 r/min, and a transmembrane pressure difference of 0.1 MPa, the permeation flux of the disc ceramic membrane decayed rapidly within 20 minutes, and then with the increase of time, the overall trend fluctuated and declined. After 90 minutes, the filtration fluxes of thermal hydrolyzed sludge, digested sludge, and AO sludge stabilized at 22.93, 13.97, and 14.20 L/（m2·h）, respectively. The disc ceramic membrane has a significant interception effect on particulate matter and dissolved organic matter of sludge from the three sources. After the digested sludge was filtered through the membrane, the solid content of the concentrated liquid could reach to 11.85%. The disc ceramic membrane cross-flow filtration system could achieve high-efficiency concentration and filtration of sludge simultaneously, providing a new approach for the solid-liquid separation treatment of sludge.

The emission of malodorous gases, such as ammonia and hydrogen sulfide, during the aerobic composting of food waste has attracted extensive attention from researchers. In order to reduce the harm of malodorous gases to residents and the environment, the types and generation mechanism of malodorous gases during the aerobic composting process of food waste were deeply explored and summarized based on existing literature. Meanwhile, the influences of different process parameters and additives on the production of malodorous gases were expounded, the existing deodorization technologies and their advantages and disadvantages were systematically sorted out, and the challenges faced in the treatment of malodorous gases in the aerobic composting of food waste were summarized. Finally, a research direction integrating in-situ odor reduction, efficient resource transformation, combined ex-situ odor removal and odor control strategies were proposed, which could offer theoretical insights and practical foundations for a more profound comprehension and resolution of odor-related issues in the aerobic composting process.

Paper waste is rich in cellulose, hemicellulose and nutrients, which can be bio-converted to energy and resources, while simultaneously reduce the environmental pollution caused by improper disposal. The implementation of suitable pretreatment technology is a crucial path in ensuring the effective bioconversion of paper waste, which has the potential to significantly enhance the bioconversion efficiency of paper waste. While it is important to develop an appropriate route for the full-scale bioconversion of paper waste to maximize energy/resource recovery and minimize waste generation. Therefore, a comprehensive and systematic analysis of the current bioconversion technology of paper waste was carried out. Based on this, an innovative bioconversion route applicable to the treatment of paper waste was proposed and the economic feasibility and environmental sustainability were comprehensive analysed. Finally, the directions forward of paper waste bioconversion technology was also prospected.

The environmental pollution and resource waste caused by livestock and poultry breeding manure represents a significant practical problem for large-scale livestock farms. Composting is an effective way for the resource utilization of livestock and poultry manure. The present research subjects were cattle manure and sawdust, which were treated with peanut shell (CSP) and without peanut shell (CS). The objective of this experiment was to investigate the effects of the addition of peanut shell bulk agent on the quality and performance of cattle manure compost. The results showed that the maximum temperature of compost in CS and CSP treatments reached 67.1 ℃ and 69.5 ℃, respectively, and the duration of high temperature lasted 26 days and 15 days, respectively. Compared with CS, CSP accelerated the pile temperature rise and the pile maturity and stability. The final germination index of CS and CSP reached 80.10% and 103.56%, respectively, and the organic matter degradation rate reached 11.35% and 13.25%, respectively. In addition, compared with that in the initial state, the E465/E665 in CS and CSP increased by 30.68% and 94.74%, respectively, the content of humus increased by 21.06% and 31.53%, respectively, the content of humic acid increased by 57.48% and 71.15%, respectively，the degree of polymerization increased by 97.96% and 189.29%, respectively, CSP had the better effect on promoting the humification process and aromaticity degree of compost. The results of Spearman correlation analysis and structural equation model demonstrated dissolved organic carbon and the ratio of carbon to nitrogen were key influencing factors in the humification process of cattle compost. The addition of peanut shell enhanced the correlation between humification parameters and spectral parameters. Meanwhile, it also increased the pathways that significantly affected the formation of humic acid, promoting the active conversion of carbon and nitrogen nutrients to humic acid, thus enhancing the degree of humification and aromaticity of compost products. The results provided a scientific basis for the efficient and directional regulation of humification in the commercial composting of cattle manure waste.

The process of anaerobic fermentation of kitchen waste can be enhanced to some extent by increasing the stirring process, which improves the organic loading of anaerobic fermentation and the efficiency of biogas production. Common mechanical stirring processes can accomplish the stirring within the anaerobic digestion tanks, but they also have several drawbacks, such as high operational energy consumption, insufficient stirring, the difficulty of daily operation and maintenance, as well as the inability to break down large particles and fibrous materials. By introducing an innovative gas-liquid mixed jet stirring technology to replace the mechanical stirring process in the anaerobic digestion process, not only the aforementioned issues could be avoided, but also the mixing effect and biogas yield within the anaerobic fermentation tanks were enhanced. This technology has been successfully and stably operated in the anaerobic fermentation project of kitchen waste for over a year. In the anaerobic fermentation tanks of kitchen waste, the gas-liquid mixed jet stirring could enhance the daily biogas production of the kitchen waste slurry and increase the CH4 content in the biogas by about 9%. At the same time, it could also increase the biogas yield per ton of slurry by about 30% and improve the biogas production rate by about 18%. From the analysis results of slurry mixing degree, equipment investment, ease of installation, operation and maintenance, treatment capacity, energy saving and consumption reduction, the gas-liquid mixed jet stirring has obvious advantages in engineering application.

With extensive use of plastic products, lots of fibrous microplastics have been discharged and accumulated in sewage sludge, posing a great challenge for sludge pyrolysis treatment. Moreover, high concentration of fibrous microplastics may alter the sludge pyrolysis behavior and sludge biochar structure, impacting the subsequent reuse of sludge. Therefore, it is urgent to understand the influence of fibrous microplastics on sludge pyrolysis behavior as well as sludge biochar structure. In this study, polyethylene terephthalate (PET, ≤0.15 mm), the typical fibrous microplastic, had been added into sludge with various mass ratios (0, 15% and 30%), and then the mixture was pyrolyzed at different temperatures (300-700 ℃). Results showed that the synergistic interaction of PET and sludge reduced yield of biochar at lower pyrolysis temperatures, while promoted yield of sludge at higher pyrolysis temperatures. Meanwhile, high abundance of PET in sludge could enhance the fraction of larger fused aromatic ring systems and increase degree of structural arrangement in biochar. In addition, for the biochar obtained at lower pyrolysis temperatures, the carbon retention ratio and long-term stability were improved by PET. However, for the biochar pyrolyzed at higher temperatures, high abundance of PET could reduce the carbon retention ratio and long-term stability.

The imported grate furnace of a domestic waste incineration project was designed with insulated furnace wall, and the coking problem was serious during operation. Through characterization analysis, it was found that calcium feldspar was the main component of the coke block, which was easy to form low-temperature eutectic mixture. When the furnace temperature was too high, the ash particles generated by incineration were prone to softening and melting, and adhered to the furnace surface with high temperature to form coke blocks. To solve the problem, the project modularized the side wall of the original furnace, making each section of the furnace wall enclosed and independent. In the local high-temperature area, the original insulated furnace wall was transformed into the air-cooled wall to reduce the temperature. After the renovation, the coking problem has been significantly improved, enhancing the safety and stability of the incinerator operation, improving the furnace thermal efficiency, and saving the operating costs. The project renovation has achieved expected results.

In order to explore the effects of exhaust gas recirculation system on the combustion characteristics of garbage incinerators and the reduction of NOx emission concentration, taking a domestic waste incineration plant in Hebei as an example, the engineering experiments were used to study the effects of operating factors such as exhaust gas recirculation ratio and oxygen concentration on furnace temperature, CO concentration, as well as NOx concentration. The results indicated that when using existing waste incineration processes and equipment, with a exhaust gas recirculation ratio of 15% and the oxygen concentration at the outlet of the economizer decreased to below 3.8%, the CO concentration could not be stably controlled below 50 mg/m3, posing a risk of environmental non-compliance. The trend of NOx concentration and oxygen concentration was consistent, and it increased with the increase of oxygen concentration. At the same time, when the oxygen concentration at the outlet of economizer was 4.5%-5.0%, the average NOx concentration and the maximum concentration decreased with the increase of the proportion of exhaust gas recirculation. The furnace temperature decreased by about 70 ℃ with the increase of the exhaust gas recirculation ratio.

Taking fly ash of a MSWI plant in Shanghai as an example, the effectiveness of an acid-washing and pyrolysis combined approach for fly ash detoxification was explored. It focused on influence in the leaching toxicity of heavy metals, chemical composition, and crystalline phase composition of MSWI fly ash before and after water washing and acid washing. Additionally, the study assessed the pollution characteristics of the wastewater generated from the acid washing process and the fly ash generated from the pyrolysis process. The results showed that after treated by water washing, the leaching toxicity of heavy metals in MSWI fly ash could meet the standard requirements of the HJ 1134—2020 Technical Specification for Pollution Control of Fly-Ash from Municipal Solid Waste Incineration. However, the leaching toxicity had fell short of meeting the standards of the GB 5085.3—2007 Identification Standards for Hazardous Wastes-Identification for Extraction Toxicity. Upon implementing acid washing treatment, the leaching toxicity of heavy metals in MSWI fly ash met the requirements of both standards. In addition, the technical feasibility of this combined system, which consists of acid-water washing and low-temperature pyrolysis, was demonstrated. The heavy metals, dioxins, and soluble chlorine,all met the pollution control requirements of HJ 1134—2020， demonstrating successful detoxification of the MSWI fly ash.

Sediment contamination caused by potential risk elements has attracted widespread attention around the world. Comprehensive ecological risk assessment is the key to precise pollution prevention and control. Therefore, many scholars at home and abroad have carried out relevant research on sediment ecological risk assessment. With the help of a variety of indices, including contamination factor, degree of contamination, risk factor, potential ecological risk index, enrichment factor and geo-accumulation index of geochemical methods, with their corresponding evaluation criteria, the pollution degree of current potential risk elements was obtained. In addition, based on the evaluation results, the source of pollution can be traced. A large number of cases in domestic and foreign literature research were summarized in this study, and the application of various indices in the evaluation of sediment pollution degree were further explored through these cases. Finally, the effective remediation countermeasures and prospects of future research for sediment were proposed.

With the rapid development of the world economy and industry, the demand for energy is constantly increasing. Promoting the resource utilization of kitchen waste oil and vigorously developing the production of biodiesel from kitchen waste oil have important significance for achieving China’s “dual carbon” goal and promoting the construction of ecological civilization. The production of kitchen waste oil in China is increasing day by day. The effective utilization of kitchen waste oil can not only prevent the food safety problems caused by its back-flow to dining tables, but also solve the environmental pollution problems caused by random discharge. The relevant management policies of kitchen waste oil in China and the collection and transportation models at home and abroad were introduced. The current situation of collection and transportation of kitchen waste oil in Shanghai was analyzed, and the management status at home and abroad was compared. At the same time, the current situation of resource utilization in Shanghai was analyzed and studied. At present, there are some problems in the collection and transportation of kitchen waste oil in Shanghai, such as limited supply capacity of raw materials, uneven quality of oil supplied by suppliers, difficulty in meeting oil collection standards for kitchen waste oil, and significant impact of region and process on pre-treatment costs. In terms of resource utilization, there are problems such as uneven treatment facilities, failure to use facilities according to regulations after installation, and low added value of resource utilization products. Finally, relevant suggestions were put forward from the aspects of standardizing and improving the recycling standards of kitchen waste oil, researching and formulating policies for the resource utilization of kitchen waste oil, promoting technological innovation and industrial upgrading, establishing and improving the whole process supervision platform of kitchen waste oil. Especially in the context of “dual carbon”, exploring the introduction of carbon offset mechanisms was innovatively proposed to replace the current subsidy policies, which has a long-term incentive effect on the sustainable development of biodiesel enterprises.

Municipal solid waste incineration has become a major source of greenhouse gas (GHG) emissions in China’s MSW treatment sector, while the GHG emissions during the transportation process have received less attention, especially in small and medium-sized cities. The slower pace of technological innovation and non-standard management in these cities may lead to higher GHG emissions due to unreasonable transportation routes and frequencies. To quantify the GHG emissions and reduction potential of transportation vehicles in the MSW collection and transportation link of Zhanjiang city, a GHG emission accounting model based on the actual transportation situation in Zhanjiang city was constructed, in accordance with 2006 IPCC Guidelines for National Greenhouse Gas Inventories, and the Monte Carlo simulation method was used for variable simulation. The results indicated that the GHG emissions from transportation vehicles of MSW collection and transportation chain in Zhanjiang city ranged from 5.20 t/d to 5.44 t/d, and carbon emission equivalent was 3.47-3.63 kg/t, which significantly increasing with the transportation distance. There is a considerable potential for GHG emission reduction in MSW transportation of Zhanjiang city. In the future, GHG emissions can be reduced through measures such as route optimization, rational siting, construction of MSW transfer stations and treatment facilities, application of information-based collection and transportation management systems, and commissioning clean-energy MSW transfer vehicles. Taking Chikan district as an example, if all MSW transfer vehicles are replaced with large-scale new energy-pure electric transfer vehicles, the reduction of GHG emissions can reach 86.52%, and the cost of using the transfer vehicles will be reduced by 31.88 million yuan after five years of operation. This study provides a scientific basis for optimizing MSW transportation routes and developing associated environmental management strategies.

With the advancement of the municipal solid waste (MSW) sorting system, the characteristics of MSW generation and substance flow in Shanghai, especially the kitchen and residual waste components and their treatment methods, have changed significantly, which directly affects the carbon emission of the MSW treatment process. The carbon emission and reduction under the background of MSW sorting policy in Shanghai were calculated using the benchmark method, focusing on kitchen and residual waste components. The results showed that from the second half of 2019 to 2022, the carbon reduction intensity of residual waste decreased from 0.19 t/t to 0.13 t/t， due to the decrease of the kitchen waste component and the increase of the rubber and plastic component in residual waste. The carbon reduction of kitchen waste increased significantly due to the anaerobic digestion treatment, and carbon emission reduction benefits gradually appeared. On the whole, the carbon reduction of kitchen and residual waste after MSW sorting was stabilized at 0.20-0.23 t/t. In the baseline scenario, the sensitivity analysis with incineration ratio as the key variable found that with the increase of the incineration ratio of MSW, the carbon emission reduction of project scenario decreased. The results of this study could bring reference value for evaluating the environmental performance of MSW sorting, and also provide ideas for carbon emission reduction strategies of the MSW treatment industry under the new situation.