Chemical Engineering
M. Benali
Abstract
This paper presents the experimental investigation of biogas production from cow dung as an alternative for fossil fuels for energy consumption. This was carried out using an 18 Liters capacity plastic keg prototype biogas plant, constructed to investigate the anaerobic digestion for generation of biogas. ...
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This paper presents the experimental investigation of biogas production from cow dung as an alternative for fossil fuels for energy consumption. This was carried out using an 18 Liters capacity plastic keg prototype biogas plant, constructed to investigate the anaerobic digestion for generation of biogas. Batch experiment was operated and daily gas yield from the plant was monitored for duration of 30 days. The digester was charged with these wastes in the ratio of 1:1, of waste to water, respectively. The mesophilic temperature ranges attained within the testing period were 20 – 35 °C. The Biogas production from cow dung fluctuates from the first day to the thirtieth day between 0 and 340 ml. The pH of cow dung gradually reduced due to acid former and methanogenes within the 30 days retention period.
S. Jijai; G. Srisuwan; S. O-Thong; I. Norli; C. Siripatana
Abstract
This study aimed to evaluate the Biochemical Methane Potential (BMP) of different types of wastewaters and sizes of granules. The granules (CS: from a cassava, SS: a seafood, and PS: a palm oil factory) and wastewaters initial Chemical Oxygen Demand (COD) were 18,800, 4,200 ...
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This study aimed to evaluate the Biochemical Methane Potential (BMP) of different types of wastewaters and sizes of granules. The granules (CS: from a cassava, SS: a seafood, and PS: a palm oil factory) and wastewaters initial Chemical Oxygen Demand (COD) were 18,800, 4,200 and 100,000 mg/l respectively). Modified Gompertz equation was used to compare the data from the experiments. Wastewater from a cassava factory gave the highest BMP when used with only granules from its own source (CS). Wastewater from seafood factory had the highest nitrogen content thus, represented the most imbalance nutrient source. In this case, mix- granules (SS+CS) gave highest BMP. Palm oil mill effluent did not match COD: N ratio criterion and had too high COD level which caused substrate inhibition. Here the mix-granules (PS+CS) gave highest BMP. In general, the larger granule size and the nutrient balance could improve the efficiency and hence increase the biogas production rate. The initial COD or different substrate has a strong effect on BMP and the maximum specific methane rates whereas the different sizes of granule have an effect on the length of lag phase period. In most cases, it was sufficient to represent the experimental data with traditional modified Gompertz equation and Monod models.
M. A. Ubaidah; S. M. H. Syed Hilmi; M. F. Mohammed Yunus; S. Tahiruddin
Abstract
Freely emitted biogas at palm oil mills has been regarded as untapped energy source nowadays, despite being recognised as major contributor to the global warming. Up till now, most of palm oil mills are still operating with the conventional anaerobic digestion systems which may not spur biogas industry ...
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Freely emitted biogas at palm oil mills has been regarded as untapped energy source nowadays, despite being recognised as major contributor to the global warming. Up till now, most of palm oil mills are still operating with the conventional anaerobic digestion systems which may not spur biogas industry to life. This study shall explore biogas production between day and night under existing mill operating conditions at KKS Bukit Benut Effluent Treatment Plant (ETP). Biogas produced during day time was 62% as compared to 38% during night time with the total methane emission of 490.3 kg/day. The methane concentration recorded at the digester tank ranged from 58.7 to 68.5%. The correlations between various factors that may influence biogas production were investigated. The finding shows that substrate feeding is the most influencial factor leading to high biogas production during day time.