Solid Waste In China Research Articles

Simulation-based hazard management of a constructed landfill for flow slide scenario

Sanitary landfills have advantages in low investment, large treatment volume, and strong adaptability, which is now the main treatment for municipal solid waste in China. However, flow slides, which present serious threat to the safety of lives and properties, are prone to occur in Chinese landfill due to leachate mound. To achieve maximum reduction in disaster loss induced by flow slides at landfills, we preliminarily explored simulation-based hazard management of a constructed landfill for flow slides scenario. A well-calibrated in-house numerical method of smoothed particle hydrodynamics was employed to conduct hazard management of flow slides. The flow slide scenario at the landfill was firstly assessed by selecting velocity and runout of flow slides to quantify the hazard. Then, different control measures, including initiative and passive prevention and control measures, were evaluated based on the achievement of hazard assessment. The proposed frame of simulation-based hazard management of flow slides can be applied to constructed or planned landfills, which can mitigate or even prevent similar disasters.

Nitrogen flow characteristics of solid waste in China

The surge in solid waste (SW) has become major issues in the fields of public health and ecological environment fuelled by the rapid development of social economy. The fate of nitrogen contained in SW (SWN) varies with different treatment methods, which will affect the environment to varying degrees. It is of great practical and guiding significance to comprehensively evaluate the sources, fate and its cascading effects of SWN. Here, a systematic SWN flow evaluation of the generation, treatment and emissions in China from 2008 to 2017 was established. During this period, the SWN flow and the N pollution emissions from SW treatment increased by 19.7% and 27.6% respectively, with the domestic garbage being the largest contributor. This shows that it is particularly important to reinforce the classified of domestic garbage and resource recycling in China. Landfill was the main treatment, accounting for 51.8% of the total SWN. Landfill and incineration were the main sources of pollution N emissions, while compost treatment has the lowest contribution rate. It highlights the urgency of changing the waste treatment methods in China. About 92.3% of the N pollution emissions was lost to the atmosphere and 7.7% to the groundwater. NH3 and NOx were the main pollutants to the atmosphere. Special attention is paid to the reduction and control of NH3 in landfill, dumping and compost processes, while NOx in incineration. This study provides scientific basis for management and disposal of SW, so as to reduce its impact on the ecological environment and develop more sustainable policies for China and other developing countries.

Energy conservation and carbon reduction potential for solid waste in China.

The generation of solid waste has increased dramatically in China, owing largely to the rapid development and expansion of the Chinese economy. The management of solid waste is critical and becoming a challenge for some cities in China. Waste recycling is an effective solution to solid waste management and seeks to balance ecological sustainability with economic improvements. This study assessed the energy conservation and CO2 emission reduction potential of solid waste using an embodied energy/carbon model from a life cycle perspective. The results showed that compared with the production of virgin materials, solid waste recycling results in a reduction of 294.2 Mtce in energy consumption, and 614.5 Mt in CO2 emission is shown in 2017. The recycling of steel waste was the highest contributor, accounting for more than 45% of energy conservation and at least 62% of CO2 reduction. If 100% recycling of recyclable waste like steel waste and plastic waste can be achieved, energy conservation and CO2 reduction could reach 551.89 Mtce and 933.69 Mt, respectively, accounting for 12.29% of energy consumption and 8.46% of CO2 emission. A robust recycling system must be established to achieve the purpose of environment production and resource conservation. The proposed evaluation framework could help in the decision-making process. The waste classification must be promoted to increase waste recovery rate and improve waste reproduction technology to maximize energy conservation and CO2 emission reduction.

Review on the Current Status of the Co-combustion Technology of Organic Solid Waste (OSW) and Coal in China

Increasing economy and population result in the rapid growth of solid waste in China, with more than 70% being carbonaceous components. The generated carbon-bearing solid waste is called as organic...

Estimating Physical Composition of Municipal Solid Waste in China by Applying Artificial Neural Network Method.

Physical composition of municipal solid waste (PCMSW) is the fundamental parameter in domestic waste management; however, high fidelity, wide coverage, upscaling, and year continuous data sets of PCMSW in China are insufficient. A traceable and predictable methodology for estimating PCMSW in China is established for the first time by analyzing 503 PCMSW data sets of 135 prefecture-level cities in China. A hyperspherical transformation method was used to eliminate the constant sum constraint in statistically analyzing PCMSW data. Moreover, a back-propagation (BP) neural network methodology was applied to establish quantitative models between city-level PCMSW and its socio-economic factors, including city size, per capita gross regional product, geographical location, gas coverage rate, and year. Results show that (1) national-level PCMSW in 2017 was estimated as organic fraction (53.7%), ash and stone (8.3%), paper (16.9%), plastic and rubber (13.6%), textile (2.3%), wood (2.2%), metal (0.6%), glass (1.5%), and others (1.0%); (2) organic fraction, paper, and plastics showed an increasing trend from 1990 to 2017, while ash and stone decreased significantly; (3) organic fractions in East, North, and Central-South China were higher than those in other regions. This enables us to fill the data gap in the practice of municipal solid waste management in China.

Incorporation of Xuan-paper waste residue in red mud/waste polyethylene composites

Xuan-paper waste residue (XPWR) is an unfamiliar and unique solid waste in China, which caused serious environmental pollution and waste of resources. Therefore, it is extremely important to explore the characteristics of XPWR and its application. In this paper, XPWR was analyzed and used as a reinforcing filler to prepare red mud/waste polyethylene/Xuan-paper waste residue (RM/WPE/XPWR) composites by molding method at 160 °C with a pressure of 10 MPa for 5−10 min. There were about 27 wt% of mineral particles and 63 wt% of organic fibers in XPWR, indicating that XPWR can be used as a reinforcing filler. When 60 wt% of XPWR was added in RM/WPE, the bending strength reached 71.81 MPa, which surpassed 43.08 % than that of RM/WPE. Besides, the addition of XPWR increased the water absorption of the composites and helped to promote the crystallization of the composites. This work presented the characteristics of XPWR and provided a new way to use XPWR.

Heavy metals decreased by water elution method on bottom ash from municipal solid waste incineration plant

By incineration treatment became the most important g municipal solid waste disposal method. The bottom ash, which accounting for 20% to 30% of the original municipal solid waste has been a large content source of municipal solid waste in China. The heavy metal will be released to the environment by the eluent produced from the bottom ash. It has a negative influence on bottom ash treatment and reuse. This study analyzed the changing of heavy metals of Cu, Ni and Zn during the elution process by the column simulation experiment. The study revealed the regulation of heavy metals migration under the condition of slow speed elution. These results can help environmental release risk assessment of heavy metal in bottom ash from municipal solid waste incineration plant.

Life Cycle Assessment of Comprehensive Utilization of Calcium Carbide Slag in Cement Kiln

The recycling utilization of solid waste is an important technical means for the sustainable development of the cement industry in China. Calcium carbide slag is a special solid waste in China, which can be used for cement production with a great advantage on CO2 emission reduction. With an view to providing methodological and data support for the development of policies in the cement industry, this paper quantitatively analyzes the environmental effects/environmental benefits of the comprehensive utilization of calcium carbide slag in cement kiln by comparing the traditional system of Portland cement clinker completely produced by natural resources with the system of cement clinker produced by calcium carbide slag based on the life cycle assessment (LCA) method given in standards and specifications of ISO 14040 series. The results show that the latter system has a better effect in material saving and carbon emission reduction, will increase the energy consumption in cement production process, and also slightly increase other pollutants (e.g. SOx, NOx, etc.) emission. The GWP, AP and EP indicators of the calcium carbide slag cement clinker system decrease compared with those of the Portland cement clinker system, while other indicators do not differ much or even slightly increase.

Green Synthesis Method and Application of NaP Zeolite Prepared by Coal Gasification Coarse Slag from Ningdong, China

In view of the current and urgent environmental protection needs, the use of industrial solid waste in China’s Ningdong is becoming more and more important. In this paper, NaP zeolite with good physical properties is synthesized by using coal gasification coarse slag (CGCS) as the raw material, without the addition of a silicon and aluminum source, without the addition of a template agent, and without high-temperature calcination. Add a small amount of NaOH and deionized water to the CGCS to adjust the molar ratio to SiO2:Al2O3:Na2O:H2O = 5.2:1.0:5.0:100. The effects of aging time, crystallization temperature, and crystallization time parameters on synthetic zeolite were studied. The raw materials and the obtained zeolite were tested by XRF, XRD, SEM, FT-IR, TG-DSC, BET, and other technologies. The results show that the specific surface area of the synthesized NaP zeolite can reach 161.06 m2/g, which has the characteristics of large specific surface area, regular morphology, and high crystallinity. We obtained NaP zeolite through a simple and low-cost synthesis method. The synthesized NaP zeolite was used to simulate the removal of ammonia nitrogen in wastewater, and the optimal removal rate was 92.67%. Among them, Na+ plays an important role in the synthesis of NaP zeolite and ion exchange with NH4+. Our research provides new ideas for solving the large-scale accumulation of CGCS and treating ammonia nitrogen in industrial wastewater. Thus, it is a promising green environmental protection and “treating waste by waste” route.

Understanding the emission pattern and source contribution of hazardous air pollutants from open burning of municipal solid waste in China

The open burning of municipal solid waste (MSW) is common in China. Therein, low–temperature anoxic combustion results in the emission of hazardous air pollutants. This study employed a dilution sampling system to conduct open burning testing on MSW samples from different functional urban areas. Additionally, modified combustion efficiency was used to distinguish smoldering and flaming combustion in two of the most common open burning practices in China: pile–up burning and barrel burning. The sampled pollutants included gaseous pollutants (e.g., CO2, CO, SO2, and NOx) and fine particles (PM2.5). This study also analyzed the carbonization compounds, 9 water–soluble ions, and 8 toxic heavy metals in PM2.5. Emission factors of air pollutants from open burning of different MSW compositions and burning modes were determined. The composition of PM2.5 from MSW open burning comprised average 43.9%, 22.5%, and 0.4% of organic carbon (OC), water–soluble ions, and toxic heavy metals (THMs), respectively. OC was found to be the primary component of PM2.5. Based on localized emission factor database, the emissions and source contribution of open burning of MSW in China were quantified. The open burning of MSW can contribute averaged 8.7%, 16.7%, 3.8%, 1.3% of PM2.5, OC, THMs, and gaseous air pollutants of reported emissions of anthropogenic sources, respectively. This work can complement current anthropogenic emission inventory and assist policy–making.

From generation to treatment: A systematic reactive nitrogen flow assessment of solid waste in China

The continuously increasing amount of solid waste (SW) that is being generated in China calls for environmental assessment and management strategies. However, the pattern and magnitude of the reactive nitrogen (Nr) loss associated with SW have received negligible attention. Here, we established a systematic Nr flow assessment of the generation, treatment and emissions of SW in China from 1978 to 2015. The Nr flow of SW increased by 87% during this period, with the livestock sector being the largest contributor. Composting and animal feed were the two main methods of SW treatment, accounting for more than half, whereas the two fastest growing treatments were remanufacturing and sewage treatment, which increased 13- and 62-fold, respectively. Each SW treatment method would inevitably lead to Nr emissions. Our results showed that the total Nr emissions from SW treatment increased from 8.7 Tg N yr−1 in 1978 to 18.6 Tg N yr−1 in 2015. The development of sustainable SW management requires considering both economic and environmental impacts. We use an optimization model (Solid Waste Optimization Life-Cycle Framework) and provide evidence that recycling SW resources will be an option for economic and environmental trade-offs.

Analysis of the factors that affect the production of municipal solid waste in China

Municipal solid waste (MSW) has received extensive attention due to its large output volume and role in urban mining. Currently the main waste disposal methods in China are sanitary landfill and incineration, but due to technological limitations, MSW causes enormous pressure on the environment and natural resources. Based on panel data of 258 prefecture-level cities in China from 2003 to 2016, this paper adopts an expanded stochastic impact by regression on population, affluence and technology (STIRPAT) model with the difference-in-difference (DID) method to study the impact of waste charging policy and key socio-economic variables on MSW and test the environmental Kuznets curve (EKC) hypothesis. The findings support a reasonable formulation of MSW and urban mining management strategies and policies. The results suggest that the implementation of waste charging policy reduced the generation of MSW, especially in the central region but has not affected the northeastern region. A significant N-shaped curve, U-shaped curve or inverted N-shaped curve exists between MSW generation and economic growth at the national level and in various areas, but no evidence supporting the traditional EKC hypothesis is found. The total amount of MSW will not decrease in a short term. Increased population and urbanization promote the generation of MSW. Increased gas penetration rate has reduced MSW, especially in Central and Western China. The share of tertiary industry has a positive relationship with MSW, especially in the eastern region, but has a negative relationship with it in the northeastern region. According to the results of the empirical analysis, policy suggestions are proposed in accordance with the national situation and regional characteristics.

Research on Pollution Control of Solid Waste in China

Solid waste is some solid and semi-solidified waste objects produced in production and other activities in our lives, typical of which are industry, agricultural, life and dangerous solid waste. Due to the restrictions on conditions and objects themselves, some objects cannot be used in production and will become waste in mankind activities, so the existence of solid waste is unavoidable. Therefore, it is impossible to stop the production of solid waste. However, it cannot be abandoned either. Instead, it is necessary to carry out proper disposal to effectively prevent secondary pollution.

Dechlorination effect of slow speed elution on municipal solid waste incineration bottom ash

The bottom ash, accounting for 20% to 30% of the original living garbage, has been a large content source of municipal solid waste in China and incineration treatment becomes the most important garbage disposal method. The water-soluble chloride ions will be released to the environment by the eluent produced from the bottom ash. It has a negative influence on bottom ash treatment and reuse. This study analyzed the changing of residue of chloride ion, ammonium nitrogen, pH value during the elution process by the column simulation experiment. The dechlorination investigation may improve the commercial application of bottom ash by revealed the regular of chloride ion migration under the condition of slow speed elution.

Focus on the investment of Waste Incineration in China—Based on PEST-SWOT analysis

Due to the rapid development of economy and the increase of population, the number of municipal solid waste in China is increasing, and the harmless disposal of waste is the urgent problem to be solved. The paper use PEST-SWOT model to analyze the investment environment of waste incinera-tion power generation industry. Also it analyzed the investment environment of waste incineration power generation industry from four aspects of policy, economy, society and technology, and point out the opportunities, threats, strengths and weaknesses of it, which can provide the reference for inventors. Based on the analysis, the paper put forward corresponding policy recommendations. It has far-reaching significance for the healthy development of waste incineration power generation industry in China.

Research on Environmental Management and Monitoring Technology of Solid Waste in China Based on Knowledge Map

In recent years, environmental governance has attracted wide attention of domestic academia, and relevant research has achieved fruitful results. Some scholars have used bibliometric methods to discuss the current research situation of environmental governance, but few have analyzed the current domestic research path of environmental governance. Based on the key words, authors and authors of the 8962 journal articles on the environmental management and environmental monitoring technology of solid waste in China from 2016 to 2018, the article uses CiteSpace software to apply knowledge maps and common word analysis. A variety of quantitative analysis methods such as cluster analysis and strategic coordinate graph analysis. The knowledge map in the field of environmental monitoring is constructed, and the map is analyzed and interpreted. The analysis results show the structural characteristics of Chinese solid waste environmental management and environmental monitoring technology in the form of knowledge map, and obtain the research frontier and its evolution law in this research field.

A value-added multistage utilization process for the gradient-recovery tin, iron and preparing composite phase change materials (C-PCMs) from tailings

Tin-, iron-bearing tailing is a typically hazardous solid waste in China, which contains plenty of valuable tin, iron elements and is not utilized effectively. In this study, a multistage utilization process was put forward to get the utmost out of the valuable elements (tin and iron) from the tailings, and a gradient-recovery method with three procedures was demonstrated: (1) An activated roasting followed by magnetic separation process was conducted under CO-CO2 atmosphere, tin and iron were efficiently separated during magnetic separation process, and 90.8 wt% iron was enriched in magnetic materials while tin entered into non-magnetic materials; (2) The tin-enriched non-magnetic materials were briquetted with CaCl2 and anthracite and roasted, then tin-rich dusts were collected during the chloridizing roasting process; (3) The roasted briquettes were infiltrated in melting NaNO3 to prepare NaNO3/C-PCMs by a infiltration method. Three kinds of products were obtained from the tailings by the novel process: magnetic concentrates containing 64.53 wt.% TFe, tin-rich dusts containg 52.4 wt.% TSn and NaNO3/C-PCMs for high temperature heat storage. Such a comprehensive and clean utilization method for tin-, iron-bearing tailings produced no secondary hazardous solid wastes, and had great potential for practical application.

The waste treatment and recycling efficiency of industrial waste processing based on two-stage data envelopment analysis with undesirable inputs

Abstract Achieving a resource-conserving and environment friendly supply chain while pursuing economic development has always been the goal of countries across the world. As an emerging industrial nation, China is battling serious environmental problems. While there have been efforts to address waste processing, researchers are now interested in gauging the efficiency of waste treatment policies. We built a two-stage data envelopment analysis model with undesirable input to assess the efficiency of recycle treating and industrial waste reuse, including wastewater, waste gas and solid wastes in China. Our model is based on a circular economy structure that proposed by Environmental Protection Institute of China. The proposed method can serve as evaluation tool for the government policy in China as well as other emerging economy. We collected the data during the critical environmental policy enforcement period: the 11th five-year plan (from 2006 to 2010). We also analyze the waste treatment efficacy for the solid waste in the 11th and 12th five-year plan period (from 2011 to 2015). In contrast to earlier studies that have mainly focused on pollution disposal efficiency, this work takes both pollution and resource attributes of waste into consideration. The results revealed that integrated efficiency of industrial waste processing system was stable over five years. It also showed that efficiency at the pollution disposal stage was higher than that at the resources reuse stage, and contributed more to overall efficiency. We also find that the efficiency of the pollution and disposal of the solid waste improved during the 11th and 12th five-year plan. Further, the study reveal that the pollution disposal stage shows a similar trend as the integrated system, while the resources reuse stage does not. Finally, it also displays that there are three efficient development modes, namely, balanced, ecosystem, and coordinate development modes. In discussion, we provide benchmarks from developed countries for different development mode. We also point out other emerging countries that can benefit from our research by identifying their development mode and formulating their environmental policy based on these benchmarks in the future.

Selenium in Chinese coal gangue: Distribution, availability, and recommendations

Coal gangue accounts for a large proportion of the solid waste in China, and greater attention has been focused on the concentrations of potentially hazardous trace elements (PHEs) than on the potentially useful trace elements (PUEs), such as selenium (Se). Chinese coal gangue is enriched in Se, and the arithmetic mean value is 2.87 mg/kg (0.06–17 mg/kg), which is 97 times higher than the average Se concentration in the upper continental crust. For coal gangue deposited during different periods, the arithmetic mean Se values are 4.25 mg/kg (C1) > 4.15 mg/kg (C2-P1) > 3.95 mg/kg (P2) > 2.65 mg/kg (T3) > 1.73 mg/kg (J1-J2) > 1.47 mg/kg (J3-K1) > 0.66 mg/kg (E–N). The Se content in lignite coal gangue is 0.88 mg/kg (0.06–4.90 mg/kg), which is 0.26 and 0.21 times lower than that in bituminite and anthracite gangue. Pearson correlation results indicate that carbonates and aluminosilicates are the dominant carriers of selenium in J3-K1 and J1-J2 coal gangue, respectively. Selenium in late Carboniferous and early Permian coal gangue probably are likely primarily associated with sulfide minerals. In addition, crushed Se-enriched coal gangue powder is considered to be a potential resource for Se-enriched fertilizer, although As (avg = 90 mg/kg) and Cr (1.07 mg/kg) are enriched in early Carboniferous and late Triassic coal gangue. The findings suggest that a comprehensive system for managing resources (e.g., coal gangue) should be developed to improve the recovery and utilization of these resources and promote a more eco-friendly society and resource conservation in China.

Testing the hydraulic conductivity of degraded municipal solid waste in China

This paper presents a study on the hydraulic conductivity of degraded municipal solid waste (MSW) and its variations with different degradation ages, using a self-made combined permeability–compression test apparatus to perform hydraulic conductivity tests. The principal outcomes were as follows. (a) The hydraulic conductivity decreased gradually with increases in the pressure, density and degradation age. The relationship between the logarithmic hydraulic conductivity and each parameter could be formulated as a linear function, and the fitted coefficients were >0·92, >0·88 and >0·79, respectively. (b) A hydraulic conductivity–pressure–density–degradation age mathematical model was established. These results can be used to provide an empirical basis to analyse the hydraulic conductivity of MSW landfills and design leachate drainage systems in China.