C d2+在大米燃料乙醇联产沼气发酵中的流向分析

摘要

The fermentation results of cadmium rice-based fuel ethanol and bio-gas showed that, the content of Cd2+varied non-significantly among liquefaction, saccharification, fermentation and distillation;the distribution pattern of Cd2+was inhomogeneous in alcohol lees after alco-hol distillation, 3%~9%of the oven dry alcohol lees accumulated 10%~27%of Cd2+, and the remaining 73%~90%of Cd2+flowed into the anaerobic fermentation system to produce bio-gas;in the fermentation of bio-gas, Cd2+presented obvious migration, above 90%Cd2+of lees solution concentrated in the sludge, and Cd2+content in the sewage reduced below the highest cadmium emission concentration. All the ex-perimental results could lay a theoretical foundation for safe and value-added transformation of cadmium rice.%“镉大米”（Cd2+含量0.45 mg/kg）乙醇联产沼气发酵试验结果显示：在液化、糖化、发酵和蒸馏各阶段Cd2+没有发生显著的迁移；经酒精蒸馏后Cd2+非均一分布于糟液和糟米查中，3%～9%的绝干糟米查中积累了10%～27%的Cd2+，剩余73%～90%的Cd2+随糟液进入厌氧发酵产沼气系统中；在沼气发酵中Cd2+出现了明显的迁移，糟液Cd2+含量的约90%以上富集于泥中，而污水Cd2+含量则降至最高镉允许排放浓度以下。以上试验结果为“镉大米”的安全增值转化奠定了理论基础。