Effect of Turning on Moisture Content in Sewage Sludge Composting

Turning can supply oxygen and increase dewatering efficiency during the composting process. This study was conducted to investigate the influence of turning on water removal. In this study, different turning modes were used in different fermentation phases. Results showed that turning in thermophilic phase improve the efficiency of water removal; in cooling phase, higher turning frequency resulted in lower water removal; turning in temperature-increasing phase had no significant effect on water removal. Unturning in the temperature-increasing phase, turning once in the thermophilic phase, and turning every 4 days in the cooling phase achieved the best effects of water removal, the water reduction was 0.566 tonston-1 matrix.

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Sewage Sludge Composting Process by Static Pile Method

Water Science & Technology ◽

10.2166/wst.1991.0654 ◽

1991 ◽

Vol 23 (10-12) ◽

pp. 1979-1989 ◽

Cited By ~ 7

Author(s):

H. Ishii ◽

K. Tanaka ◽

M. Aoki ◽

T. Murakami ◽

M. Yamada

Keyword(s):

Sewage Sludge ◽

Moisture Content ◽

Natural Ventilation ◽

Water Evaporation ◽

Bulking Agents ◽

Intermittent Aeration ◽

Feed Mixture ◽

Composting Process ◽

Average Temperature ◽

Sludge Composting

This paper reports the results of experiments on the static pile composting process undertaken in different conditions. The experiments have revealed the following:–In order to compost dewatered sludge with polymer without any bulking agents, we used recycled compost to adjust the moisture content of dewatered sludge.When the moisture content of feed mixture, which was dewatered sludges and recycled composts, was lowered to approximately 50%, the raw sludge could be composted by either natural ventilation or intermittent aeration.–When the BOD of feed mixture was lower than 50 g/kg-DS, the fermentation temperature did not reach 60°C and the moisture content of the mixture was not lowered during composting period.–The required composting time was approximately 50 days for natural ventilation (at an average temperature of 10°C or 24°C) and approximately 35 days for intermittent aeration (at an average temperature of 10°C to 24°C), when the moisture content and the BOD of finished compost was 40% or less and 30 g/kg-DS or less, respectively.–There was a highly positive correlation between the amount of water evaporated and the amount of BOD removed. This result suggested that the amount of water evaporation could be deduced from the amount of BOD removed.

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Stabilization of heavy metals in sewage sludge composting process

Water Science & Technology ◽

10.2166/wst.2001.0591 ◽

2001 ◽

Vol 44 (10) ◽

pp. 95-100 ◽

Cited By ~ 10

Author(s):

K.-Y. Chiang ◽

S.-D. Yoi ◽

H.N. Lin ◽

K.-S. Wang

Keyword(s):

Heavy Metals ◽

Sewage Sludge ◽

Total Concentration ◽

Physicochemical Characteristics ◽

Limit Values ◽

Sludge Compost ◽

Composting Process ◽

Agricultural Applications ◽

Maturation Rate ◽

Sludge Composting

This study investigated the stabilization of heavy metals in a sewage sludge composting process using kaoline addition. The results indicate that the temperature increased rapidly to the thermophilic phase (>55°C) at day 1. The additives enhanced the rate of biodegradation and microbial activity during the co-composting process. The changes in pH (ranging from 8 to 8.5) and electrical conductivity (EC) (≤3 mS/cm) were in compliance with the best conditions during the co-composting process. The C/N ratio was determined in each co-compost sample as an indicator of the co-compost maturity. From the end product of the co-compost experiment, changes in the ratios indicate that the additives promote the co-compost maturation rate. Based on the physicochemical characteristics of the co-compost, the potential use for sewage sludge resource recovery as manure is suggested. The total concentrations of Pb, Cd, Cr, Cu, and Zn in the co-compost product were far below the limit values for agricultural use. The leachability of Pb, Cu, and Cr decreased with increasing co-composting time. That is, the kaoline additive has an inhibitory capacity for leaching heavy metals. The Cd concentrations in the sludge compost were below the detection limits. Because the total concentration of Zn was high in the sludge compost and most soluble Zn was leachable, the leachability of Zn ranged from 25% to 29%. As a result of the physicochemical characteristics and heavy metal stabilization, the selected additive was shown to improve the sewage sludge compost quality and provide information for agricultural applications.

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Study on the Enzyme Activity Change during the Aerobic Composting Process of Sewage Sludge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.706 ◽

2014 ◽

Vol 955-959 ◽

pp. 706-710

Author(s):

Jun Ling Niu ◽

Jun Hui He

Keyword(s):

Enzyme Activity ◽

High Temperature ◽

Sewage Sludge ◽

Moisture Content ◽

Cellulase Activity ◽

Moisture Loss ◽

Intensity Change ◽

Composting Process ◽

Activity Intensity ◽

Sludge Disposal

Compost is widely used for treating urban garbage and sewage sludge. The enzyme activity is one of the important parameters of microbial quantity and its activity intensity change in the composting process, and all of the biochemical reactions during the composting process are carried out with the enzymes involving. The composting progress and the material change are directly reflected by the enzyme activity. In Zhengzhou Bagang sludge disposal plant, sludge was mixed with straw to compost together and with the technology of high temperature solid state aerobic slot for sludge treatment. This study was done to research the tendency of peroxide enzyme activity, cellulose enzyme activity, pH, conductivity, moisture content in the process of compost. The result showed that at the beginning of the compost, cellulase activity increased first and then decreased gradually and tended to be stable. The catalase activity was higher at the beginning of the compost and at the period of temperature raising it was stable basically, then decreases quickly and after that it maintain on the lower level. The moisture content declined gradually during the composting process, and in the period of high temperature there are more moisture loss. PH increased at first, and with the temperature raised to high the pH decreased gradually and tended to be stable. Conductivity increased first, then decreased gradually to steady.

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Managing the sewage sludge composting process

Treatment and Use of Sewage Effluent for Irrigation ◽

10.1016/b978-0-408-02622-2.50016-x ◽

1988 ◽

pp. 152-163

Author(s):

George B. Willson

Keyword(s):

Sewage Sludge ◽

Composting Process ◽

Sludge Composting

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Influence of maize straw content with sewage sludge on composting process

Journal of Water and Land Development ◽

10.1515/jwld-2016-0020 ◽

2016 ◽

Vol 30 (1) ◽

pp. 43-49 ◽

Cited By ~ 5

Author(s):

Wojciech Czekała ◽

Jacek Dach ◽

Damian Janczak ◽

Anna Smurzyńska ◽

Agnieszka Kwiatkowska ◽

...

Keyword(s):

Sewage Sludge ◽

Porous Structure ◽

High Price ◽

Carbonaceous Materials ◽

New Members ◽

Composting Process ◽

Cereal Straw ◽

Maize Straw ◽

Materials Used ◽

Sludge Composting

Abstract After entrance to EU in 2004, the management of sewage sludge has become more and more important problem for the new members. In Poland, one of the most promising technologies is composting process of sewage sludge with carbonaceous materials. However, the high price of typically used cereal straw forces the specialists to look for new and cheap materials used as donor of carbon and substrates creating good, porous structure of composted heap. This work presents the results of sewage sludge composting mixed with sawdust and maize straw used to create structure favorable for air exchange. The results show dynamic thermophilic phase of composting process in all cases where maize straw was used.

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