The Impact Of Disinfectants Methane Fermentation Pilot Study

In twentieth century, with the spread of rural modernization, a large number of countryside trashes aren't disposed reasonably, which caused environmental pollution. So the development of biogas construction is promoted rapidly. As a renewable and clean energy, biogas is given more attention by the government. For livestock manure and sewage on the livestock farms, fermentation technology is considered as the most effective means of saving and environmental protection. The main components of biogas are methane and carbon dioxide, which wouldn't pollute the air and be harmful to crops and human health. The comprehensive benefits of energy, environment and economic were achieved in the ecology, agriculture and animal husbandry.Considering the actual farm environment, in order to prevent disease infecting and breaking out, disinfectant is used as an important measure. However, the process of methane fermentation is restrained by a variety of disinfectants containing chemical properties, so biogas digesters could not work naturally, and dung could not be handled very well. To make the biogas digesters used naturally, calcium oxide, excellent net chloride and formaldehyde are used as disinfectants; the effect of biogas fermentation was studied in this paper. The experimental results are follows:(1) The calcium oxide can restrain biogas fermentation. The increase of the addition can increase inhibitory action. When additive concentration is 0.05%,0.1% and 0.2%, the output of gas is reduced by 8.99%,12.19% and 19.22%, respectively. At the same time, the total volatile fatty acid and activity of fatty acid hydrolyses is increased, but the activity of cellulose hydrolysis enzymes and amylase is decreased. When additive concentration is 0.05%, the total volatile fatty acid and activity of fatty acid hydrolyses is increase by 30.21% and 2.04%, the activity of cellulose,α-amylase and (α+β)amylase, are decreased by 52.5%,58.76% and 63.79%. The normal environment of fermentation is broken by calcium oxide, and the PH value is increased and the gas output is reduced.(2)The restraint effect of the excellent net chlorine on biogas fermentation is stronger. The increase of the addition can reduce the fermenting. The gas output is restrained completely when additive concentration is 0.2%. At the same time, the total volatile fatty acid and activity of fatty acid hydrolyses is increased, but the activity of cellulose hydrolysis enzymes and amylase is decreased. When additive concentration is 0.05%, the total volatile fatty acid and activity of fatty acid hydrolyses is increased by 33.14% and 123.67%, the activity of cellulose and (α+β) amylase is decreased by 46.58% and 52.27%.(3)The restraint effect of the formaldehyde on fermentation is most obvious. The increase of the addition can reduce the fermenting. When additive concentration is 0.01%,0.03%,0.05%, the gas output is reduced by 40.58%,31.51% and 52.67%, respectively. At the same time, the total volatile fatty acid and activity of fatty acid hydrolyses is increased, but the activity of cellulose hydrolysis enzymes and amylase is decreased. The gas output is restrained completely when additive concentration is 0.05%. When additive concentration is 0.05%, the total volatile fatty acid and activity of fatty acid hydrolyses is increased by 18.78% and 135.13%, the activity of cellulose and a-amylase is decreased by 78.57% and 83.65%.(4)The experimental analysis on gas composition for formaldehyde shows that methane content will be decreased with the addition of formaldehyde. When additive concentration is 0.03%, the methane is decreased by 21.82% and the carbon dioxide is increased by 29.73%.(5)The experimental results of three added disinfectant shows that when the calcium oxide additive concentration is 0.2%, gas production is not inhibited fully, while when the excellent net chlorine additive concentration is 0.2%, gas production has been inhibited completely, and when the formaldehyde disinfectant additive concentration is 0.05%, gas production has been inhibited completely. Data from a variety of activities can also reflect that the inhibition of formaldehyde is the most, the excellent is the second, and the calcium oxide is the least. However, the PH environment would be damaged by the calcium oxide.