Composting is widely used for recycling of urban sewage sludge to improve soil properties, which represents a potential pathway of spreading antibiotic resistant bacteria and genes to soils. However, the dynamics of antibiotic resistance genes (ARGs) and the underlying mechanisms during sewage sludge composting were not fully explored. Here, we used high-throughput quantitative PCR and 16S
Results showed hyperthermophilic composting enhanced decomposition and humification of municipal sludge in the short terms, while heavy metal concentrations and speciation had no significant change with high copper and zinc levels (101-122 and 292-337 mg/kg, respectively) in compost samples.
Composting is controlled fermentation that converts organic matter aerobically and produces stable humic and pre-humic compounds (figure 1). Aeration will only be effective if the medium is air-permeable. Dewatered sludge often has a low porosity; a bulking agent has to be added, usually in the form of a carbonaceous support (20% of the mixture
May 8, 2020 · Composting is a type of aerobic digestion. Sewage sludge can be combined with other waste materials such as wood chip, straw or green wastes prior to composting to provide a pasteurised product. Around 20−30% of the volatile solids can be converted to carbon dioxide through composting. Composting employs natural mesophilic and thermophilic
Aug 17, 2021 · In this study, a comparative analysis is carried out of the compost produced from industrial composting facilities that process municipal solid waste (MSW) and sewage sludge (SS) and compare them with those produced from green waste (VR).
Jun 21, 2019 · Nutrient recovery from secondary resources, such as wastewater, has received increasing attention in recent years. Nutrient cycle sustainability and recycling approaches are important measures under development and considerations. This paper aims to present an overview of routes and technologies for nutrient recovery from sewage sludge and measures for improving their sustainability. First
Jun 24, 2022 · Moreover, four bio-enhanced degradation scenarios of FQs were set up according to the different temperatures and carbon–nitrogen ratio (C/N) in the sewage sludge composting stage, and the molecular dynamic (MD) simulation assisted by protein–protein docking was used to screen the external environmental factors that promote the degradation
Jun 24, 2022 · Moreover, four bio-enhanced degradation scenarios of FQs were set up according to the different temperatures and carbon-nitrogen ratio (C/N) in the sewage sludge composting stage, and the molecular dynamic (MD) simulation assisted by protein-protein docking was used to screen the external environmental factors that promote the degradation of
Composting is considered an effective treatment option to eliminate or substantially reduce potential hazards relating to the recycling of sewage sludge (SS) on land. The variation of four major types of hazards (heavy metals, instability, pathogenic potential and antibiotic resistance) was studied during laboratory-scale composting of two
Oct 19, 2023 · Here we review applications of hyperthermophiles in composting , focusing on the unique improvements provided by hyperthermophiles in composing temperatures, product safety, nitrogen preservation and humification. Inoculation of hyperthermophiles allows temperature of composting to reach over 80°C.
Nov 1, 2019 · It is thus clear that bioleaching conditioning treatment (79.1%) is much more useful than either adding natural zeolite into composting piles or adjusting the C/N ratio of sewage sludge to reduce
Jan 1, 2019 · The dehydration of sewage sludge consists in lowering the water content of sediments and increasing the dry matter content. It is the key process for posttreatment and further processing of sewage sludge. During this process, the reduction of the volume of sewage sludge occurs simultaneously. The removal of water from sewage sludge is realized
Nov 11, 2023 · Sewage sludge treatment and disposal has become a pressing issue in China. Sewage sludge was passivated by composite phosphorus-bearing materials to decrease heavy metals bioavailability. The optimum immobilizing conditions that were 5 g of phosphate rock, 3 g of calcium superphosphate for 100 g sludge and 14 d of passivation time were determined by an orthogonal test. The physico-chemical
May 12, 2022 · This work reports the results obtained with an innovative configuration of a closed-static solar greenhouse for sludge drying. The novelty of the solar greenhouse configuration consisted in using a forced ventilation system to provide hot air for sludge drying and the utilization of solar irradiation for energy supply. Wet sewage sludge (97% humidity) was successfully dried up to a residual
Therefore, industrial-scale sewage sludge composting was shown to be an effective tool for the elimination of indicator strains of fecal contamination resistant to certain antibiotics in routine use. Thus, it contributed to the reduction of the spread of ARGs in environmental microbiomes, as well as the transfer of the same in the food chain.