0
Article Tier 2 Detection Methods Gut & Microbiome Human Health Effects Remediation Sign in to save

Integral analysis of hydrodynamic cavitation effects on waste activated sludge characteristics, potentially toxic metals, microorganisms and identification of microplastics

The Science of The Total Environment 2021 47 citations

AI summary Read the abstract

Researchers investigated hydrodynamic cavitation as a pretreatment for waste activated sludge, analyzing its effects on sludge characteristics, toxic metals, microorganisms, and identifying microplastics present in the sludge to improve anaerobic digestion efficiency.

Study Type Environmental

Wastewater treatment plants, the last barrier between ever-increasing human activities and the environment, produce huge amounts, of unwanted semi-solid by-product - waste activated sludge. Anaerobic digestion can be used to reduce the amount of sludge. However, the process needs extensive modernisation and refinement to realize its full potential. This can be achieved by using efficient pre-treatment processes that result in high sludge disintegration and solubilization. To this end, we investigated the efficiency of a novel pinned disc rotational generator of hydrodynamic cavitation. The results of physical and chemical evaluation showed a reduction in mean particle size up to 88%, an increase in specific surface area up to 300% and an increase in soluble COD, NH4-N, NO3-N, PO4-P up to 155.8, 126.3, 250 and 29.7%, respectively. Microscopic images confirmed flocs disruption and damage to yeast cells and Epistilys species due to mechanical effects of cavitation such as microjets and shear forces. The observed cell ruptures and cracks were sufficient for the release of small soluble biologically relevant dissolved organic molecules into the bulk liquid, but not for the release of microbial DNA. Cavitation treatment also decreased total Pb concentrations by 70%, which was attributed to the reactions triggered by the chemical effects of cavitation. Additionally, the study confirmed the presence of microplastic particles and fibers of polyethylene, polyethylene terephthalate, polypropylene, and nylon 6 in the waste activated sludge.

More Papers Like This

Article Tier 2

Integral analysis of hydrodynamic cavitation effects on waste activated sludge characteristics, potentially toxic metals, microorganisms and identification of microplastics

AI summary Read the abstract

Researchers tested hydrodynamic cavitation — a process using high-speed water flow to create pressure changes — as a pretreatment to improve sewage sludge digestion and measured its effects on microplastics in the sludge. The process reduced some sludge properties that limit biogas production, but its effect on microplastic fragmentation was also assessed. The study is relevant to understanding how wastewater treatment alters microplastic size and abundance in sludge spread on farmland.

Article Tier 2

Integral analysis of hydrodynamic cavitation effects on waste activated sludge characteristics, potentially toxic metals, microorganisms and identification of microplastics

AI summary Read the abstract

This is a spectroscopy dataset (FTIR and Raman data) from a study on the effects of hydrodynamic cavitation on waste activated sludge, including analysis of potentially toxic metals, microorganisms, and microplastic identification. The data supports assessment of cavitation as a combined sludge treatment and microplastic analysis technique.

Article Tier 2

Fate, characteristics, and potential threat of microplastics in sludge under various dewatering treatments

AI summary Read the abstract

Researchers compared four different sludge dewatering treatments used at wastewater plants and examined how each process affected the microplastics trapped in the sludge. They found that advanced oxidation treatments altered the surface properties of the microplastics and increased their ability to absorb heavy metals. The findings raise concerns that certain sludge treatment methods could make microplastics more environmentally hazardous when the treated sludge is disposed of or reused.

Article Tier 2

The Effects of Microplastics on Floc Formation, Nutrient Removal and Settleability in Wastewater Treatment

AI summary Read the abstract

Researchers examined the interactions of microplastics with activated sludge in wastewater treatment plants, investigating effects on floc formation, nutrient removal efficiency, and settleability to understand how microplastic contamination may compromise treatment performance.

Article Tier 2

Thermal hydrolysis alleviates polyethylene microplastic-induced stress in anaerobic digestion of waste activated sludge

AI summary Read the abstract

Scientists found that pretreating waste sludge with heat before anaerobic digestion reduced the negative effects that polyethylene microplastics have on the process. The thermal treatment improved methane production and helped maintain healthy microbial communities even in the presence of microplastics. The study suggests that thermal hydrolysis could be a practical strategy for wastewater treatment plants dealing with microplastic-contaminated sludge.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper