| The rapid development of economy and society urbanization and improvement of the living standards lead to gradual increase of municipal solid waste (MSW),kitchen waste accounts for 60%-70% of MSW. The kitchen waste owns a high recycling value with the characteristics of rich in organic matter and nutrients. However, the kitchen waste owns the high moisture content and perishable and is easy to breed bacteria. If disposed of improperly, it will bring to environmental health hazards. As people improve environmental protection requirements, the kitchen waste treatment is taken seriously and gradually attention.Compared with the traditional processing methods, kitchen waste anaerobic digestion biogas technology has important implications for solving environmental problems caused by kitchen waste and energy crisis. At present, domestic reports on the kitchen waste treatment with IC reactor are raw. This paper using IC reactor for treating food waste study glucose nutrition and food actually waste water respectively for IC reactor initiated feasibility, optimize the parameters of EM fungi hydrolyzed-IC reactor and uses PCR-DGGE technology to acclimation sludge determination of success.1.Start the reactor:(1) Using glucose nutrient to cultivate anaerobic sludge. At the beginning, reaction temperature control in (35±1)℃,the influent water pH to 8.0-8.3 and the CODcr concentration at the beginning of the experiment is 1370mg/L,and the hydraulic retention time goes through 6h,12h、18h respecively.Cultivating domesticated in 34 days,CODcr concentration gradually increased to 9560 mg/L.At the same time, the organic load from 5.48 kg/(m3·d) gradually increased to 12.75 kg/(m3·d).The removal rate of CODcr can stabilize more than 93%,and up to 95.55% at most.So it means the start is to be finished;(2)Using actual kitchen wastewater to cultivate anaerobic sludge.At the beginning, reaction temperature control in (35± 1)℃,the influent water pH to 7.7-8.1 and the CODcr concentration at the beginning of the experiment is 2070mg/L, and the hydraulic retention time goes through 12h、18h respecively.Cultivating domesticated in 26 days,CODcr concentration gradually increased to 9360 mg/L.At the same time, the organic load from 4.14 kg/(m3·d) gradually increased to 12.48 kg/(m3·d).The removal rate of CODcr can stabilize more than 90%,and up to 95.32% at most.So it means the start is to be finished.2.Research on the operationg of hydrolysis of kitchen waste-IC reactor:(1)EM technology pretreats kitchen waste slurry.It hydrolyzes kitchen waste by using EM bacteria in advance,and observes the influence of effects of hydrolyzing kitchen waste by value of dissolved oxygen (DO)、EM bacteria dosing and reaction temperature. The results show that,the concentration of sCOD upgraded from 1680mg/L to 5320mg/L and the value of DE upgraded from 2.31%L to 12.66%,when the value of dissolved oxygen was 1.5mg/L in 24h. And the concentration of sCOD upgraded from 2435mg/L to 7640mg/L and the value of DE upgraded from 2.24%L to 19.99%,when EM bacteria dosing was 0.6%in 48h.It was helpful for the growth of EM bacteria when reaction temperature was between 30 to 35℃;(2) The influence of internal circulation quantity during processing the wastewater. Open the forced internal circulation and Regulate the internal circulation reflux ratio (Q:Qin)in 1:1,1:2,1:3、1:4,1:5,when the start is to be finished.The results show that,the best internal circulation reflux ratio was 1:4, at this time, CODcr removal rate can reach 96%,and the gas production of every kg CODcr is 0.769 m3/d.3.Microecology of the ludge:(1) Starting test by glucose nutrient, the value of coenzyme F420 and Extracellular polymeric is 0.32umol/gVSS and 27.58mg/gVSS when anaerobic sludge is cultivated.Bacillus and globular bacteria are predominant bacteria in sludge microorganism by scanning electron microscope.Analyze microbial community of sludge samples by using PCR-DGGE technology and the results show that:There are lots of and many kingds of microbial content in the anaerobic sludge and they mainly belong to Veillonellaceae、Pseudomonadaceae、 unclassified_Bacteria、Betaproteobacteria and Proteobacteria;(2) Starting test by actual kitchen wastewater, the value of coenzyme F420 and Extracellular polymeric is 0.41umol/gVSS and 25.92mg/g VSS when anaerobic sludge is cultivated.In order to observe the microbial diversity between the top and bottom sludge in the reactor system, the test samples the top and bottom sludge and analyze microbial community of sludge samples by using PCR-DGGE technology. The results show that:the top and bottom sludge respectively contain Burkholderialesand Clostridiales in the system.Wastewater quality is different between the top and bottom of the reactor, so there is the difference in the microorganisms of sludge. |
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