feasibility of waste lime sludge (ls) obtained from acetylene gas production industry wasstudied during co-composting of vegetable waste for enhanced volatile solids reduction. four different trialswere carried out with varying percentage of ls combinations i.e. trial 1, trial 2, trial 3 and trial 4. increasedaddition of waste ls raised the levels of ph in the compost, thereby volatizing the ni...

in the temperature range of 10 to 80 ºc and in a batch digester, a typical activated sludge was digested aerobically. reaction rate constants were determined by measuring the amounts of volatiles removed from the suspended solids at different time intervals during the process. the maximum value of the reaction rate constant (0.45 d-1) occurred in the temperature range of 55-60˚c. removal of ind...

Separation of solids from liquid swine manure and subsequent thermochemical conversion (TCC) of the solids fraction into oil is one way of reducing the waste strength and odor emission. Such processing also provides a potential means of producing renewable energy from animal wastes. Gravity settling and mechanical separation techniques, by means of a centrifuge and belt press, were used to remo...

Integrated anaerobic/aerobic systems have been considered feasible alternatives concerning technical and economic aspects for treating domestic wastewaters. The main modification in the UASB reactor concerns this association with the RAIB. The UASB effluent was distributed through openings along its side walls to the RAIB, allowing the elimination of collecting channels and feeding devices from...

In this study, the effect of sludge retention time (SRT) on oxic-settling-anoxic (OSA) process was determined using a sequencing batch reactor (SBR) attached to external aerobic/anoxic reactors. The SRT of the external reactors was varied from 10 to 40d. Increasing SRT from 10 to 20d enhanced volatile solids destruction in the external anoxic reactor as evidenced by the release of nutrients, ho...

The feasibility of the anaerobic co-digestion of coffee solid waste and sewage sludge was assessed. Five different solid wastes with different chemical properties were studied in mesophilic batch assays, providing basic data on the methane production, reduction of total and volatile solids and hydrolysis rate constant. Most of the wastes had a methane yield of 0.24-0.28 m3 CH4(STP)/kg VS(initia...

To increase conversion and product concentration, mixed-acid fermentation can use a countercurrent strategy where solids and liquids pass in opposite directions through a series of fermentors. To limit the requirement for moving solids, this study employed a propagated fixed-bed fermentation, where solids were stationary and only liquid was transferred. To evaluate the role of agitation, contin...

Anaerobic digestion is a naturally occurring biological process in which large numbers of anaerobic bacteria convert organic matter into methane and carbon dioxide (a mixture called biogas) in the absence of air. It is a widely used biological process for treating wastewater solids. This process stabilizes the organic matter in wastewater solids, reduces pathogens and odors, and reduces the tot...

Anaerobic digestion is a naturally occurring biological process in which large numbers of anaerobic bacteria convert organic matter into methane and carbon dioxide (a mixture called biogas) in the absence of air. It is a widely used biological process for treating wastewater solids. This process stabilizes the organic matter in wastewater solids, reduces pathogens and odors, and reduces the tot...