Application of peroxymonosulfate-ozone advanced oxidation process for simultaneous waste-activated sludge stabilization and dewatering purposes: A comparative study

Surplus sludge disposal and treatment are major issues in wastewater treatment plants. Discharge plasma oxidation is an effective approach for sludge dewatering and digestion. In this study, excess sludge disintegration by non-thermal discharge plasma coupled with thiosulfate (TSA) was investigated. After 20 min of the single discharge plasma treatment, the soluble chemical oxygen demand (SCOD) increased to 404.93 mg L−1, and it climbed even more to 549.08 mg L−1 after adding 15 mmol L−1 of TSA. The water content of the filter cake also reduced even more in the presence of TSA. There was an appropriate dosage of TSA available. In the discharge plasma coupled with TSA system, reactive oxygen species (·OH and O2−) were generated and had significant involvement in the disintegration of the sludge. The addition of TSA enhanced the production of OH. These reactive oxygen species decomposed the floc structures and facilitated the transformation of organic compounds, resulting in a decrease in the average size of the sludge aggregates. The ratio of soluble extracellular polymer substances (S-EPS) was enhanced, while the ratio of the tightly bound fraction was reduced after the treatment. Thus, discharge plasma coupled with TSA promoted microbial cell lysis and facilitated the release of intracellular organic matter and bound water, ultimately enhancing the sludge’s dewaterability.

Section: Changes In the Eps Distributionsupporting

confidence: 93%

Excess Sludge Disintegration by Discharge Plasma Coupled with Thiosulfate

Jin,

Lin,

Yang

et al. 2023

“…The moisture content of the de-cemented cake is limited to a minimum of 59.79% bound water content of 2.32 g/gTS [21] Peroxymonosulfate-Ozone pH 11.0 PMS/O3 = 0.06; O3 = 12.5 mmol/L 70% reduction in sludge filtration time (TTF) relative to virgin sludge [36] Activated persulfates…”

Section: Pfs-o3mentioning

confidence: 99%

Advances in Chemical Conditioning of Residual Activated Sludge in China

Liang

Wang

Sun

et al. 2023

Municipal sludge is characterized by high organic matter content, high viscosity, and fine particles, resulting in poor dewatering performance. This article analyzes the composition and properties of municipal sludge, examines the factors affecting the dewatering performance of sludge and the mechanisms corresponding to each influencing factor, and introduces chemical conditioning in detail. Chemical conditioning includes flocculation conditioning, oxidation conditioning, acid-base conditioning, and aggregate conditioning. The principles and applications of existing sludge conditioning technologies are systematically analyzed. By comparing the advantages and disadvantages of different technologies, it is pointed out that the key to developing sludge conditioning technology lies in developing a more appropriate combination of the sludge conditioning and dewatering process according to the sludge quality of different municipal wastewater treatment plants, taking into account their local environment, input costs, subsequent sludge disposal methods, and other factors, and further optimizing the sludge dewatering process by developing new efficient and environmentally friendly sludge conditioning agents.

“…Usually, chemical agents are added to the sewage sludge to enhance the physico-chemical properties of the sludge so that the sludge is easily dewatered. Coagulation/flocculation [9], the advanced oxidation process [10], and an acid/base treatment [11] are all classified as chemical conditioning. Physical conditioning refers to the use of the porous materials [12], heating [13], freezing and thawing [14], ultrasonic treatment [15], or electric fields [16] to improve the dewatering capacity of sludge.…”

Section: Introductionmentioning

confidence: 99%

Preparation, Properties, and Application of Biochar for Improving Sewage Sludge Dewatering Performance: A Review

Deng

Chen

et al. 2023

Biochar is a widely available carbon-based material that has been used for soil remediation and sewage treatment. However, in recent years, biochar has received more attention as a conditioning agent to improve the dewatering performance of sewage sludge. The sludge from the secondary sedimentation tank of wastewater treatment plants has high microbial activity and poor dewatering performance, which poses a challenge to sludge dehydration. Biochar and modified biochar can be injected into sludge as a skeleton to effectively reduce sludge compressibility, increase permeability, and release bound water, thus improving the dewatering performance of sludge. In this review, the preparation and characteristics of biochar are described, the current methods of sludge dewatering and the properties of sludge are introduced, and the research on the application of biochar in sludge conditioning is summarized. In addition, the existing problems and future development directions of biochar in sludge conditioning are discussed.