The Research Of Trace Metal Elements In Raising Production Of Biogas

The methane fermentation is a process that combinats a variety of microorganisms with replacement complex biological reaction process. In the complexity of the fermentation process, the interdependence and restriction of no-produce-methane bacterium and methanogens make a equilibrium state in the fermentation.Methanogen is the core of the methane fermentation.And methanogen is the last member of the anaerobe chain in nature carbon cycle. The study on changes of methanogen in the methane fermentation can make us realize fermentation degree, optimize the fermentation condition and enhance the methane output. And it will benefited to improve the efficiency of methane fermentation.Micro-organisms only meet certain nutritional conditions in order to normal growth, reproduction and the completion of a variety of physiological needs. Their roles can be summarized as the three major role: the formation of their own physical structure, providing energy and regulate metabolism of. Micro-organisms need the basic nutrients are six categories of elements, namely: water, carbon and nitrogen sources, inorganic salts, growth factors and energy. and so on.This article aims to enhance the biogas production by adding small amounts of metal elements to enhance the microbial activity and look at several aspects of this carried out the research work:First of all: The corn-based ethanol production after the alcohol stillage material conditions to cultivate micro-organisms in the medium to add a different trace metal elements, to increase the production of methane gas methane bacteria. Through a large number of parallel experiments to determine the combination of trace metal elements in six hydrated nickel chloride, ferrous chloride tetrahydrate, cobalt chloride six hydrate. Determined by orthogonal experiments of three kinds of trace metal salts to add volume, respectively, 200ug/L·d, 1000ug/L·d, 100ug/L·d.Secondly: The raw material for acetic acid fermentation substrate for anaerobic experiments, anaerobic fermentation of continuous and intermittent anaerobic methane fermentation of bacteria methane gas to a large number of experiments on the above experimental results verified. The results show that: continuous anaerobic fermentation technology than non-continuous anaerobic fermentation technology for gas production growth rates higher than 69%. Therefore, a continuous anaerobic fermentation for an experimental basis, adding to its trace metal salts of single factor experiments and the results of a single factor experiment based on orthogonal experimental design to determine the substrate acetate continuity of anaerobic fermentation process obtained the best to add the amount of trace metal salts were six hydrated nickel chloride: 400ug/L·d, ferrous chloride tetrahydrate: 3000ug/L·d, 6hydrated cobalt chloride: 150ug/L·d, through this program allows bacteria producing methane gas as high as 96%.Thirdly: In the enterprise to conduct pilot-scale production experiment, pairs of expanded granular sludge bed reactor and upflow sludge blanket reactor experimental comparisons, and expanded granular sludge bed reactor to detect a variety of indices . Experimental results show that adding trace metal salt experiments, the two kinds of reactors have increased methane gas production and gas production growth rate has greatly improved. But the expanded granular sludge bed reactor and upflow sludge bed reactor, In comparison, the expanded granular sludge bed reactor, a greater number of methane gas production, gas production rate of up to 19.74%. This indicates that: expanded granular sludge bed reactor is more suitable for corn ethanol stillage processing. Can be seen that by adding these trace metal elements, can greatly increase the amount of bad handling of liquid, while prolific gas, thereby enhancing the rate of methane production.The innovation of this paper is as follows:According to the enterprise of maize alcohol wastewater characteristics and treatment needs, from bacteria nutritional point of view, select the appropriate type of trace metal elements in combination, enhance the activity of bacteria and effective to improve biogas production in anaerobic digestion process , and also can effectively enhance the removal of chemical oxygen demand, reduce its chemical oxygen demand values, so that the emission reduction goals.