Study On Device And Expeirment Of Straw Compartment Continuous Anaerobic Digestion

In this paper, the compartment continuous anaerobic digestion device was designed for theproblems that high consumption for pre-treatment process, difficulties for material feeding anddischarging, poorly controlling of the reaction process, floating crusts of raw materials, longer digestioncycle, lower raw material conversion rate in crop straw anaerobic digestion technology. Take the purestraw anaerobic digestion experiment with the corn, wheat and rice straw in the device, without addingany exogenous substance, study on biogas production effect and operation status of different rawmaterials in the device, analyze the feasibility of device, the main conclusions are as follows:(1)Experiment with corn straw in preliminary design device, found that it can produce methaneefficiently and quickly only after cutting and biogas slurry soaking pretreatment without pretreatmentwhich is trival, high energy consumption, heavy pollution, for example, preprocessing crushing andacid-base, to prove that anaerobic digestion can be carried out smoothly in the device.(2)The temperature was (35士1)。C, for60days, HRT is30days, the length of raw material is18cm,115g TS quality in compartment, the concentration of TS is5.85%, and the transmission process ofcompartment is simple and run smoothly, biogas production rises steadily, the maximum daily biogasproduction is21.33L and19.94L/d when full load runtime of ten raw compartment (1150g), TS biogasproduction rate is0.495L/g, VS gas production rate is0.598L/g, volumetric gas production rate of0.309m3/(m3d),(3)Then begin the next experiment on corn and rice and wheat straw with the device made afteroptimization design in structure.The condition is same to the corn experiment, the length and quality ofraw material is20cm and250g TS, the concentration of TS is17.71%,16.31%and16.33%. Corn,wheatand rice straw cumulative gas production reach2100.09L,1312.13L and1250.60L, average daily gasproduction are44.76L,25.65L and26.66L in the time of full load operation, TS raw material gasproduction rate are0.537L/g,0.308L/g and0.319L/g, VS raw material gas production rate are0.649L/g,0.373L/g and0.369L/g, volumetric gas production rate was0.632m3/(m3d),0.362m3/(m3d) and0.363m3/(m3d).(4)Static batch experiment, corn straw, wheat straw, rice straw respectively reach the peak of gasproduction at7th,2ed,4th day, then gas production decline to80ml at the fortieth day to end theexperiment, are38450ml,21746ml,16937ml, the cumulative gas production30days before the end are35723ml,20298ml,15608ml, which is more than92%of the cumulative gas production of40days, soit is appropriate to select30days detention period. There are great advantages for compartment devicethrough the comparison of gas production.