Recent Research on Municipal Sludge as Soil Fertilizer in China: a Review

Abstract

Due to the annual increase in wastewater treatment in most Chinese cities, a major environmental issue has arisen: safe treatment, disposal, and recycling of municipal sludge. Municipal sludge has a high content of carbon and essential nutrients for plant growth; hence, it has gained interest among researchers as a soil fertilizer. This study discusses the potential usage of municipal sludge as soil fertilizer (indicators include nitrogen (N), phosphorus (P), and trace elements) along with its shortcomings and drawbacks (potentially toxic elements (PTEs), organic matter (OM), pathogens, etc.) as well as reviews the latest reports on the role of municipal sludge in land use. The use of municipal sludge as a soil fertilizer is a sustainable management practice and a single application of sludge does not harm the environment. However, repeated use of sludge may result in the accumulation of harmful chemicals and pathogens that can enter the food chain and endanger human health. Therefore, long-term field studies are needed to develop ways to eliminate these adverse effects and make municipal sludge available for agricultural use. Graphical Abstract

Single-step pyrolysis of biomass waste-derived activated carbon encapsulated zero-valent nickel NPs for the purification of antibiotic-contaminated water

“…In comparison to the findings of previous reports, these results demonstrate a significantly improved performance in terms of CPX removal time. Ahmed et al 44 reported that it took 60 min to remove 75% of the CPX onto ZVI@ biochars, whereas the ZVNi@AC achieved the same level of removal within a mere 5 min.…”

Recent innovations in fertilization with treated digestate from food waste to recover nutrients for arid agricultural fields

“…was not detected in any case. DS was produced exclusively on the basis of food wastes, which are usually not as rich a source of enteropathogens as municipal waste and human and animal manure (Manyi-Loh et al 2016; Zhang et al 2023). However, plant material can also be a source of this type of microorganisms due to the contact with soil (Patel et al 2014).…”

Study adsorbents based on bent-Al13-CS-CTA and its application to the removal of CR from wastewater

“…22,23 CS molecular chains penetrate the interlayer of columnar bent and attach to its surface, strengthening its adsorption capacity. Chong Huang et al 24 looked into the adsorption effect of acid-chitosanbentonite composite on Cr 6+ in solution. Their ndings suggest that the maximum adsorption capacity may be 111.47 mg g −1 and that spontaneous and endothermic monolayer chemical adsorption is the adsorption mechanism.…”