摘要
尽管Modified Gompertz模型与料菌比和发酵浓度之间没有直接的函数和变量关系,但是料菌比和浓度的变化必然导致Modified Gompertz模型参数的改变,因此可以通过Modified Gompertz模型参数的变化特征对料菌比和发酵浓度是否适宜作出合理的评价.据此本研究将采用中温批量发酵,分别设计单因素实验和多因素均匀设计(Uniform Design)实验,并利用ModifiedGompertz模型拟合的方法,同时考察料菌比和发酵浓度对城市生活垃圾批量沼气发酵的影响.结果表明,累积产气量随时间的变化与Modified Gompertz模型具有较好的相关性,从而获得最大累积产气量、最大产气速率和滞留时间模型参数,并由此推算出VS产气率及产气速率等评价指标.这些参数和指标的变化特征表明,发酵含量是影响最大累积产气量、最大产气速率、VS产气率和VS产气速率的主要因素,而料菌比的影响相对较小,特别是对VS产气率和VS产气速率几乎不产生影响,并表明城市生活垃圾沼气发酵的VS含量在4%~8%比较适宜,料菌比在1.5∶1~2.5∶1比较适宜.
Although there was not direct correlation between modified Gompertz model(MGM) and ratio of feedstock to inoculum(RFI) and fermentative concentration(FC),the changes of RFI and FC absolutely resulted in the change of MGM's parameters,so it could make a suitable estimation for RFI and FC by means of the characteristic value of MGM's parameters.Based on this theory,MGM was used to investigate the effect of both RFI and FC on batch mesophilic anaerobic digestion of organic fraction of municipal solid waste(OFMSW) by using single-factor experiment and Uniform Design multi-factor experiment.The results showed that accumulative biogas yield as a function of time had an strong excellent correlation with MGM from which kinetic parameters of anaerobic digestion,such as the maximum accumulative biogas yield,the maximum biogas rate,lag-phase time,biogas potential of VS,and biogas rate of VS,could be directly or indirectly obtained.The characteristics of these kinetic parameters indicated that fermentative concentration had a greater influence on the maximum accumulative biogas yield,the maximum biogas rate,biogas potential of VS,and biogas rate of VS,while the ratio of feedstock to inoculum had a less or no impact on those parameters,especially biogas potential of VS and biogas rate of VS.It also indicated that the optimum VS concentration for anaerobic digestion of OFMSW was 4%-8% and ratio of feedstock to inoculum was 1.5∶1-2.5∶1.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2011年第6期1843-1850,共8页
Environmental Science
基金
昆明理工大学固体废弃物资源化国家工程中心项目
关键词
MODIFIED
Gompertz模型
城市生活垃圾
沼气发酵
料菌比
发酵含量
挥发性固体
Modified Gompertz model
organic fraction of municipal solid waste
anaerobic digestion
ratio of feedstock to inoculum
fermentative concentration
volatile solid(VS)