复合陶粒基质甲烷氧化能力评价

Evaluation the methane oxidation capacity of composite ceramsite

以陶粒为载体,利用甲烷、氧气和养分制备出新型甲烷氧化基质——复合陶粒基质。以水分、孔隙度、碳氮比、NO3-浓度为影响因素,以复合陶粒基质的最大甲烷氧化速率(Vmax)为目标函数,进行L16(45)正交试验。以正交试验单因子方差分析结果(F值)为权重分配依据,应用层次分析法建立复合陶粒基质的甲烷氧化能力评分机制。评价结果表明,不同因素水平的复合陶粒基质评价分值与试验结果(Vmax)呈线性相关关系。在16组试验中最好的基质条件为:碳氮比1∶1(摩尔比)、水分(以与最大持水力比率计)50%、孔隙度30%、NO3-0.61 g/L。以100分为基准,该条件下所得基质的评价分值为99.043,相应的Vmax为2.845 6μmol/(g.h)。

A novel composite matrix of methane oxidation was produced with ceramsite as carriers under favorable condition of methane,oxygen and nutrients.The L16（45） orthogonal experiments were designed considering moisture,porosity,carbon-nitrogen ratio and NO-3concentration as the impact factors and maximal methane oxidation rate（Vmax） of composite ceramsite as the response function.Based on Variance Analysis（F ratio） of orthogonal experiments,Analytic Hierarchy Process（AHP） method was used to assign weights for four different impact factors and establish the scoring mechanism.The statistical analysis results showed the scores was linear correlated with Vmax（R2=0.885） in different factors and levels of orthogonal experiments.The optimum conditions for ceramsite composition were obtained as follow： carbon-nitrogen ratio of 1∶1,ratio of water content to maximum water-retention capacity was 50%;porosity of 30% and KNO3concentration of 0.61 g/L.Evaluation results showed the composite ceramsite prepared under these optimum conditions had the highest score of 99.043（100 scores as the perfect matrix）,its methane oxidation capacity was 2.845 6 μmol/（g·h）.