Municipal sludge dewatering properties and heavy metal distribution: Effects of surfactant and hydrothermal treatment

Liu, Xingshuang; Wang, Jin; Liu, Enhui; Yang, Tianhua; Li, Rundong; Sun, Yifei

doi:10.1016/j.scitotenv.2019.136346

Cited by 40 publications

(9 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With the rapid development of the metallurgical industry, a large amount of metallurgical industry sludge has been produced. The composition of industrial sludge is complex because of the variety of sources, mainly heavy metals, organic pollutants, viruses and microorganisms (Liu et al 2020b;Lu et al 2019;Romdhana et al 2009). At present, the above substances contained in industrial sludge are not  Corresponding author: Tel.…”

Section: Introductionmentioning

confidence: 99%

Novel combination of bioleaching and persulfate for the removal of heavy metals from metallurgical industry sludge

Chen

Cui

et al. 2022

Environ Sci Pollut Res

View full text Add to dashboard Cite

The objective of this study was to remove heavy metals from the metallurgical industry sludge by bioleaching alone and bioleaching combined with persulfate (PDS). The results showed that the removal of Cu, Zn, Pb and Mn reached to 70%, 83.8%, 25.2% and 76.9% by bioleaching alone after 18 d, respectively. The experiment of bioleaching combined with PDS was carried out in which the optimal additive dosage of K2S2O8, 8 g/L, was added to bioleaching after 6 d. After 1 h, the removal of 4 heavy metals reached 75.1, 84.3, 36.7 and 81.6%, respectively. Compared with bioleaching alone, although the increase in removal efficiency was not obvious, the treatment cycle was distinctly shortened from 18 d to 6 d + 1 h. Scanning electron microscopy (SEM) results showed that the surface morphology of the sludge was changed significantly by the combined treatment. The content of heavy metals was significantly reduced after bioleaching combined with PDS by energy dispersive X-ray spectroscopy (EDX). The treated sludge mainly existed in a stable form, and the bioavailability was reduced with European Community Bureau of Reference (BCR) morphology analysis. Therefore, this study proved that the combination of bioleaching and PDS was an efficient method to remove heavy metals from metallurgical industry sludge.

show abstract

Section: Introductionmentioning

confidence: 99%

Novel combination of bioleaching and persulfate for the removal of heavy metals from metallurgical industry sludge

Chen

Cui

et al. 2022

Environ Sci Pollut Res

View full text Add to dashboard Cite

show abstract

“…Chemical conditioning is another important means applied to bene t mechanical dewatering. The traditional chemical conditioner such as surfactant (Liu et al 2020;He et al 2020), occulants and polymers (Hu and Chen 2021) promote the agglomeration of ne sludge particles into large ocs through charge neutralization or adsorption bridging, which is more conducive to precipitation and compression (Rao et al 2019). EPS are necessary components of activated sludge which have a high a nity for water and thus are highly hydrated.…”

Section: Introductionmentioning

confidence: 99%

Settleability and Dewaterability of Sewage Sludge with Modified Diatomite

Luo

et al. 2021

Preprint

View full text Add to dashboard Cite

In this study, cationic polyacrylamide (CPAM) modified diatomite and cetyl trimethyl ammonium bromide (CTAB) modified diatomite were synthesized and used as conditioner in sewage sludge dewatering. The effects of these two types of modified diatomite on the dewaterability and settling performance of activated sludge were studied. The mechanism of the two types of modified diatomite in the activated sludge system was elucidated. The efficiency of CPAM-modified diatomite was better than that of CTAB-modified diatomite in improving the settleability and dewaterability performance of sludge. The results indicated that specific resistance to filtration (SRF) was decreased from 8.52×1012m/Kg to 0.92×1012 m/Kg, and the water content in the remaining sludge cake after pumping filtration was decreased from 92.2% to 68.1%. by adding 0.4% of CPAM-modified diatomite and pH=3.5, which result in optimal sludge settling of activated sludge. Further studies showed that the polymer/surfactant adsorbed in diatomite increased sludge dewaterability and improved the sedimentation rate as a result of stripping extracellular polymer substances (EPS) and damaging the internal structure of sludge conduce bound water releasing. According to scanning electron microscope(SEM) images, two types of modified diatomite powder not only kept the porous, but also shown more complete and uniform structure in comparison to nature diatomite.

show abstract

“…Sewage sludge generally has poor compressibility and dewatering performance, which require considerable energy and resource consumption. Moreover, it may contain toxic and harmful substances such as organic matters, heavy metals, and so forth, which increase the difficulty of sludge treatment and disposal. , However, the rich organic content could enable the sewage sludge to be used as a soil amendment addition or organic fertilizer after appropriate treatment . Therefore, resource utilization has become a hot and key research issue in the treatment and disposal of sewage sludge.…”

Section: Introductionmentioning

confidence: 99%

Enhanced Deep Utilization of Low-Organic Content Sludge by Processing Time-Extended Low-Temperature Thermal Pretreatment

Liu

Wang³

et al. 2021

ACS Omega

View full text Add to dashboard Cite

Anaerobic digestion is an important way for maintaining sewage sludge stability, reduction, and resource recovery. However, the low organic content generally limits methane production. Recently, thermal hydrolysis has been widely used for sludge pretreatment to improve the anaerobic digestion efficiency. Generally, an increased temperature is preferred to enhance the solubility of organic matters in the sludge. However, high energy requirement comes with increased temperature. Application of low-temperature thermal treatment could overcome this drawback. However, the appropriate low-temperature pretreatment time is still uncertain. In this study, an extended contact time with low thermal pretreatment (90 °C) was chosen to realize a more efficient and economical digestion process of low-organic content sludge. The results demonstrated that the solubilization of proteins and carbohydrates was significantly promoted by the contact time-extended thermal hydrolysis pretreatment. The following anaerobic digestion efficiency of low-organic content sludge was also dramatically improved with the prolonged contact time. The maximum methane production could reach around 294.73 mL/gVS after 36 h of 90 °C treatment, which was 5.56 times that of the untreated groups. Additionally, based on the energy balance calculation, extending the thermal hydrolysis time resulted in a more economically feasible anaerobic digestion than increasing the temperature. The dewatering properties and the stability of the heavy metals were also reinforced, implying the advanced deep utilization of the digested low-organic content sludge. In conclusion, sludge pretreated by low-temperature thermal hydrolysis with a prolonged contact time could be more effective for low-organic content sludge treatment and disposal.

show abstract

Municipal sludge dewatering properties and heavy metal distribution: Effects of surfactant and hydrothermal treatment

Cited by 40 publications

References 24 publications

Novel combination of bioleaching and persulfate for the removal of heavy metals from metallurgical industry sludge

Novel combination of bioleaching and persulfate for the removal of heavy metals from metallurgical industry sludge

Settleability and Dewaterability of Sewage Sludge with Modified Diatomite

Enhanced Deep Utilization of Low-Organic Content Sludge by Processing Time-Extended Low-Temperature Thermal Pretreatment

Contact Info

Product

Resources

About