不同C N比堆肥碳素物质变化规律研究

针对堆肥化过程中常伴有少量CH4等温室气体排放造成环境污染等问题,采用密闭堆肥化装置,进行了不同碳氮比和通气条件下,堆肥过程中的气体释放规律、影响因子及其对堆肥理化性质的影响研究。结果表明,C/N=25、30堆肥处理的有机物降解率高于低碳氮比处理;全氮含量随着有机物的降解而浓缩,随着堆肥的进行而不断提高,到堆肥结束时,C/N=15、20、25和30处理的全氮含量分别为23.5、24、27.8 g.kg-1和28.4 g.kg-1;堆肥过程中,C/N=15、20、25和30的堆肥处理CH4累积排放为0.67、0.95、2.25g.kg-1和1.80 g.kg-1,损失比例占初始碳物质的0.39%、0.5%、1.24%和0.92%,并且CH4气体的排放主要集中在高温前期,高温期越长,排放的温室气体越多。高温期适当增大通气量,对于控制堆肥温度和减少温室气体生成有双重作用。

C Matter Change of Composting with Different C/N

Aiming at the problem that a small amount of CH4 and other greenhouse gas emission in the composting process caused environ-mental pollution and other issues,the laws of the gas release,the impact factor and its effect on physical and chemical properties of compost in the composting process with different carbon and nitrogen ratio and ventilation conditions were studied.The results showed that：organic matter degradation rate of the disposals with C/N ratio of 25 and 30 was higher than that with low-carbon and nitrogen;the total nitrogen con-tent concentrated with organic matter degradation,and continuously improved with the composting process,by the end of composting,the total nitrogen of the disposals with C/N ratio of 15,20,25 and 30 respectively were 23.5,24,27.8 g.kg-1 and 28.4 g.kg-1;in the composting pro-cess,cumulative CH4 emissions of the disposals with C/N ratio of 15,20,25 and 30 respectively were 0.67,0.95,2.25 g.kg-1 and 1.80 g.kg-1,the loss proportion of the initial carbon material were 0.39%,0.5%,1.24% and 0.92%.CH4 gas emission mainly occured in pre-heat high-temperature and the longer the period was,the more greenhouse gas emissions.Ventilation amount should be increased properly in high-tem-perature period,which plays a part both in temperature control and in greenhouse gas reduce.