Application of Ultrasound Pretreatment for Sludge Digestion

Yeow, Show Kuan; Peng, Wong Lai

doi:10.1002/9781118404089.ch4

Cited by 4 publications

(3 citation statements)

References 91 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is generally agreed upon that the possible mechanism of ultrasonic radiation is acoustic cavitation (Gedanken, 2004). Cavitation is a process in which mechanical activation destroys the attractive forces of molecules in the liquid phase thereby allowing bubble growth through the diffusion of solute vapor (Yeow and Peng, 2012). The energy inside of the bubbles will release and lead to high temperatures and pressures in microscopic regions resulting in chemical excitation that breaks chemical bonds.…”

Section: Ultrasonic Radiationmentioning

confidence: 99%

Remediation of Polychlorinated Biphenyls (PCBs) in Contaminated Soils and Sediment: State of Knowledge and Perspectives

Jing

Fusi

Kjellerup

2018

Front. Environ. Sci.

114

View full text Add to dashboard Cite

Polychlorinated biphenyls (PCBs) are one of the persistent organic pollutants (POPs) used worldwide between the 1930 and 1980s. Many PCBs can still be found in the environment such as in soils and sediments, even though their use has been heavily restricted. This review summarizes the most frequent remediation solutions including, phytoremediation, microbial degradation, dehalogenation by chemical reagent, and PCBs removal by activated carbon. New insights that emerged from recent studies of PCBs remediation including supercritical water oxidation, ultrasonic radiation, bimetallic systems, nanoscale zero-valent iron based reductive dehalogenation and biofilm covered activated carbon, electrokinetic remediation, and nZVI particles in combination with a second metal are overviewed. Some of these methods are still in the initial development stage thereby requiring further research attention. In addition, the advantages and disadvantages of each general treatment strategy and promising technology for PCBs remediation are discussed and compared. There is no well-developed single technology, although various possible technologies have been suggested. Therefore, the possibility of using combined technologies for PCB remediation is also here investigated. It is hoped that this present paper can provide a basic framework and a more profound prospect to select successful PCB remediation strategies or combined technologies.

show abstract

Section: Ultrasonic Radiationmentioning

confidence: 99%

Remediation of Polychlorinated Biphenyls (PCBs) in Contaminated Soils and Sediment: State of Knowledge and Perspectives

Jing

Fusi

Kjellerup

2018

Front. Environ. Sci.

114

View full text Add to dashboard Cite

show abstract

“…Macro algae was pretreated with sonication at a particular input energy of 75 MJ/kg TS and only 20% of the methane was released, but when the sonication energy was increased to 100–200 MJ/kg TS, methane yield was increased to between 80 and 90% [ 63 ]. About 50% of biogas yield increase was recorded when ultrasound was used at full-scale sewage sludge plant [ 64 ]. When ultrasound was combined with alkaline pretreatment for thickened pulp mill waste, there was a notable improvement in the initial digestion, but the total methane yield was not improved [ 65 ].…”

Section: Optimization Of Biogas and Methane Yieldsmentioning

confidence: 99%

Optimization of biogas yield from lignocellulosic materials with different pretreatment methods: a review

Olatunji

Ahmed

Ogunkunle

2021

Biotechnol Biofuels

120

View full text Add to dashboard Cite

Population increase and industrialization has resulted in high energy demand and consumptions, and presently, fossil fuels are the major source of staple energy, supplying 80% of the entire consumption. This has contributed immensely to the greenhouse gas emission and leading to global warming, and as a result of this, there is a tremendous urgency to investigate and improve fresh and renewable energy sources worldwide. One of such renewable energy sources is biogas that is generated by anaerobic fermentation that uses different wastes such as agricultural residues, animal manure, and other organic wastes. During anaerobic digestion, hydrolysis of substrates is regarded as the most crucial stage in the process of biogas generation. However, this process is not always efficient because of the domineering stableness of substrates to enzymatic or bacteria assaults, but substrates’ pretreatment before biogas production will enhance biogas production. The principal objective of pretreatments is to ease the accessibility of the enzymes to the lignin, cellulose, and hemicellulose which leads to degradation of the substrates. Hence, the use of pretreatment for catalysis of lignocellulose substrates is beneficial for the production of cost-efficient and eco-friendly process. In this review, we discussed different pretreatment technologies of hydrolysis and their restrictions. The review has shown that different pretreatments have varying effects on lignin, cellulose, and hemicellulose degradation and biogas yield of different substrate and the choice of pretreatment technique will devolve on the intending final products of the process.

show abstract

“…Ultrasonic frequency and reaction time and sonication power level and time highly influence the ultrasonic field and, therefore, feedstock pretreatment. Factors such as the digester size, type, and solvent used also have significant impacts on the biomethanation process [23,46].…”

Section: Pre-treatment Of Biomass Materialsmentioning

confidence: 99%

Anaerobic Digestion of Lignocellulosic Waste Materials

Kamperidou

Terzopoulou

2021

Sustainability

View full text Add to dashboard Cite

Nowadays, the climate mitigation policies of EU promote the energy production based on renewable resources. Anaerobic digestion (AD) constitutes a biochemical process that can convert lignocellulosic materials into biogas, used for chemical products isolation or energy production, in the form of electricity, heat or fuels. Such practices are accompanied by several economic, environmental and climatic benefits. The method of AD is an effective method of utilization of several different low-value and negative-cost highly available materials of residual character, such as the lignocellulosic wastes coming from forest, agricultural or marine biomass utilization processes, in order to convert them into directly usable energy. Lignin depolymerization remains a great challenge for the establishment of a full scale process for AD of lignin waste. This review analyzes the method of anaerobic digestion (biomethanation), summarizes the technology and standards involved, the progress achieved so far on the depolymerization/pre-treatment methods of lignocellulosic bio-wastes and the respective residual byproducts coming from industrial processes, aiming to their conversion into energy and the current attempts concerning the utilization of the produced biogas. Substrates’ mechanical, physical, thermal, chemical, and biological pretreatments or a combination of those before biogas production enhance the hydrolysis stage efficiency and, therefore, biogas generation. AD systems are immensely expanding globally, especially in Europe, meeting the high demands of humans for clean energy.

show abstract

Application of Ultrasound Pretreatment for Sludge Digestion

Cited by 4 publications

References 91 publications

Remediation of Polychlorinated Biphenyls (PCBs) in Contaminated Soils and Sediment: State of Knowledge and Perspectives

Remediation of Polychlorinated Biphenyls (PCBs) in Contaminated Soils and Sediment: State of Knowledge and Perspectives

Optimization of biogas yield from lignocellulosic materials with different pretreatment methods: a review

Anaerobic Digestion of Lignocellulosic Waste Materials

Contact Info

Product

Resources

About