Effect of calcium peroxide assisted microwave irradiation pretreatment on humus formation and microbial community in straw and dairy manure composting

Microwave pretreatment of wastewater sludge technology—a scientometric-based review

“…6 , Chinese and Indian research and development organizations are currently the main players in this research area. Also, through publications in recent years, it can be understood that the main research topics of these organizations are currently focused on the use of different catalysts to synergistically increase the heating rate of microwaves (Li et al 2022b ; Xie et al 2022 ; Lu et al 2023 ), the use of microwave-assisted technology to enhance the energy conversion rate of bio-waste (Yang et al 2022 ; Chandrasekaran and Chithra 2022 ; Usmani et al 2023 ), and microwave pretreatment technology to enhance hydrogen production from sludge (Dinesh Kumar et al 2020 ; Zhao et al 2023 ). This bodes well for the future development of sludge pretreatment in favor of industrialization and energy efficiency.…”

“…This also improved the stability of the digester by increasing the buffering capacity of the digester, AS: FVW (25:75) had the highest nutrient dissolution and 10% methane yield with microwave pretreatment at 300 W Co-digestion and microwave pretreatment make hydrolysis no longer the limiting step in AD, but methane production the new limiting step, and how to improve the final methane yield and reduce energy efficiency costs becomes a new challenge (Agrawal et al 2023 ) CaO 2 -assisted microwave pretreatment Maize straw CaO 2 -assisted microwave pretreatment effectively reduced the crystallinity of maize straw and increased the initial water-soluble carbon (WSC) content and lignocellulose degradation. Degradation of lignin, cellulose, and hemicellulose reached 25.48%, 43.38%, and 66.29%, respectively The addition of CaO 2 , although it increases the degradation of lignin by microwave pretreatment, creates residues in the maize straw sludge that can be a burden on subsequent residual sludge treatment (Lu et al 2023 ) Combined microwave and hydrogen peroxide pretreatment Tannery sludge Due to the high content of macromolecular organic matter in tannery sludge, microwave pretreatment can be used to break it down and recover not only bio-based chemicals (e.g., short-chain fatty acids), but also biofuels from the sludge Although microwave pretreatment can recover most of the polluting waste from tannery sludge, this treatment method is only at the laboratory stage and the industrialization and continuity of the treatment system still requires a lot of research (Tuci et al 2022 ) Microwave and CaO co-pyrolysis Sewage sludge and water hyacinth Microwave pretreatment facilitates the reduction of activation energy and promotes pyrolysis reactions. The addition of CaO reduced the yields of acids and sugars by 10.52% and 5.08%, respectively.…”