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Municipal solid waste (MSW) puts an extreme pressure on MSW management for its complexity and the emission of greenhouse gases (GHG). It can provide important suggestions for waste management by predicting GHG emissions. At present, most of the basic data for predicting GHG emissions comes from previous studies, which may cause errors between the research results and the actual situation. The physical composition, proximate analysis, and ultimate analysis of MSW from the waste transfer station in Hefei were systematically analyzed in this study. Seven scenarios of MSW management were simulated; the GHG emissions and offsets during transport, recovery, and treatment were calculated by utilizing the IPCC guidelines and emission factors. The results showed that the physical composition of MSW in Hefei was 49.64% food, 27.45% plastic, and 12.80% paper. MSW in Hefei was not suitable for composting due to the high C/N ratio, and waste classification made Hefei domestic waste more suitable for incineration. When compared with the existing treatment method, no landfill reduced 38.93% of GHG emissions. GHG emissions were reduced by 60.05% with the complete separation of food waste. This study can provide support for choosing MSW treatment and reducing GHG emissions in Hefei.

Excessive ammonium and phosphate in aquatic settings may produce major eutrophication. Adsorbents can be used to reduce the eutrophication of natural water bodies. In this study, a sustainable and efficient ceramic adsorbent (sludge/biomass ash ceramsite [SBC]) was prepared by using sludge and biomass ash with a weight ratio of 1:1; the sintering parameters were 1070°C for 15 min. The NH4+‐N and P adsorption capabilities were improved by utilizing 1 mol L−1 NaOH and 1.6 mol L−1 La(NO3)3·6H2O for modification. When the pH and duration were 7 and 1440 min, respectively, the maximum bending capacity of ammonia nitrogen and phosphorus was 3.2 and 2.1 mg g−1 at 308 K. The pseudo‐second‐order kinetic model better describes the adsorption dynamics of NH4+‐N and P, whereas the Langmuir model better describes the adsorption isotherm models of NH4+‐N and P. The adsorption mechanism of SBC‐NaOH on NH4+‐N is ion exchange between Na+ and NH4+, whereas the adsorption mechanism of SBC‐La on phosphorus is ion exchange and La3+ adsorption. SBC combines efficient wastewater purification with the reuse of solid waste. The findings gave rise to the possibility of recycling ceramics as a plant fertilizer with a delayed release in the future. Practitioner Points New ceramsite was made from sludge and biomass ash. NH4+‐N (3.2 mg g−1) and P (2.1 mg g−1) were effectively adsorbed by ceramsite. The mechanism of NH4+‐N and P adsorption by ceramsite was studied. Absorbed ceramsite can be used as slow‐release fertilizer in plant cultivation.

Increasing amounts of arsenic-containing impurities in Cu ores may deteriorate the smelting process and aggravate the environmental impact of slag tailing. Geochemical, mineralogical and chemical speciation characteristics were investigated to elucidate the association and environmental stability of metal(loid)s in copper slag tailing. Results shown that the bulk chemical compositions of the selected slag tailing are Fe2O3 (54.8%) and SiO2 (28.1%). The selected slag tailing may lead to multi-elemental contamination potential for the elevated concentrations of environmental sensitively elements. The mineral phases in slag tailing are silicate (fayalite), oxides (magnetite and hematite), sulfides (galena, sphalerite, arsenopyrite and chalcopyrite). The invariably overlap of silicate, iron, arsenic and oxygen in the elemental distribution suggested that arsenic is existed silicate minerals as Si-Fe-As-O phases. Meanwhile, arsenic is also associated with sulfide minerals and oxides. The percentages of arsenite (As(III)) and arsenate (As(V)) are 59.4% and 40.6% in the selected slag tailing, respectively. The slag tailing is regarded non-hazardous waste for the tiny amounts of toxic elements in leachates. Nevertheless, the slag tailing should be property disposed for the elevated carbonate bound of As and Cu in the slag tailing.