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Leachate generated during the treatment and disposal of municipal solid wastes (MSWs) can be an important source of pharmaceutical and personal care products (PPCPs) in the environment. With the implementation of garbage classification policy in China, the disposal methods of MSWs have changed, while its impacts on the occurrence of PPCPs in the generated leachate remain unknown. In this study, we investigated 49 target PPCPs in the leachates of classified MSWs, i.e. residual waste leachate (RWL) and food waste leachate (FWL), and revealed the influence of garbage classification implementation on the occurrence of PPCPs in leachates to be treated. The results showed the concentration and mass load of target PPCPs in the RWL samples (median values: 34.9 ng/L and 52.3 mg/d, respectively) were significantly higher than those in the FWL samples (median values: 19.3 ng/L and 14.5 mg/d, respectively). Macrolide (ML) antibiotics were the predominant PPCPs in the RWL samples, while in the FWL samples, quinolone (QL) antibiotics exhibited the highest concentration and mass load. The implementation of garbage classification policy led to the reduction of PPCP mass load (from 739 g/d to 262 g/d) in leachates to be treated. The findings are helpful for better designing or managing MSW treatment and disposal processes to minimize the emission of PPCPs from MSW leachates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Policy is a powerful tool determining solid-waste treatment and disposal. In 2019, China carried out the "garbage-classification policy" in 46 cities. So-called dry garbage is then separated from municipal solid waste and treated alone by incineration. This work investigated the influence of the policy on contents and leaching characterizations of municipal solid waste incineration fly ash. Median value of Cl was significantly increased from 17.43 wt% to 28.63 wt%. Median content of CaO maintained a similar value (51.21 wt% and 47.27 wt%). Ten year ago, CaClOH was not generally observed in fly ash. However, this phase was widely detected nowadays. Median value of heavy-metal (Zn, Pb, Cu, Cd, Cr, and Ni) was decreased from 9007.69 mg/kg to 7652.72 mg/kg. Thus, the policy also positively affected hazardous-waste collection. Heavy-metal leaching concentrations were decreased and chemical speciation became more stable because CaClOH supplied more alkalinity and binding ability for heavy metals. Therefore, fly-ash treatment technologies and their running parameters should be regulated to adapt above new characterizations after the garbage-classification policy., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Although waste incineration is a promising disposal method, it produces unwanted combustion by-products, such as toxic dioxins, that can be unintentionally emitted. Kitchen scraps can result in incomplete combustion of waste, which accelerates the formation of dioxins, especially for the small-sized incinerators without identical operating temperature. Consequently, garbage classification before waste incineration is critical for dioxin control in the small-sized waste incineration industries. To date, the influence of garbage classification on dioxin emissions has not been quantified. In this study, a model framework integrating the grey prediction model and autoregressive prediction model was established and used to predict future dioxin emissions from small-sized waste incineration. If garbage classification is ideally strictly implemented, annual dioxin emissions could be reduced by up to 1697 g TEQ over the next 10 years. Garbage classification reduced emissions by about 30.7% compared with incineration of mixed municipal solid waste without classification (5534 g TEQ over the next 10 years). The established model framework can effectively assess the influence of garbage classification on dioxin emissions from waste incineration, which could facilitate the widespread adoption of garbage classification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The GHGs contributions (tally by carbon emissions) during treatment of domestic food waste and residual waste from pilot communities (contained 2365 families) in Shanghai, China, under different Modes induced by garbage classification were investigated. It was found that under the present condition of garbage classification in Shanghai, 51.8% of the food waste could be separated finally. With garbage classification, the load of landfill was saved by 17.3% (Mode 2) and 16.5% (Mode 3), the moisture of garbage for incineration was reduced by 13.6%, and the lower heating value (LHV) of garbage was increased by 16.2%. Applying the life-cycle assessment (LCA) methodology and Life Cycle Inventory (LCI) with material flows, net carbon emissions during the treatment of garbage were found to be in the following order: Mode 3 (1.60 × 10 -3  kg CE/kg waste) < Mode 2 (4.85 × 10 -3  kg CE/kg waste) < Mode 1 (4.94 × 10 -3  kg CE/kg waste) < landfill (1.49 × 10 -2  kg CE/kg waste). Mode 2 and Mode 3 were replaceable patterns of Mode 1, and anaerobic digestion was the recommendable strategy to recover energy from food waste. Especially, there was no obvious benefit of increasing the separation proportion of food waste to 60% (or above) for reducing net carbon emissions in the following treatment processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)