干发酵对稻草结构及产沼气的影响

为了防止稻草焚烧产生的环境污染,采用厌氧干发酵方式对稻草进行资源化处理.通过稻草元素的分析、X射线衍射(XRD)及红外光谱(FT-IR)的分析,考察了干发酵及预处理对稻草结构的改变.结果表明,稻草干发酵60d单位挥发固体累积产气量278.1mL/g (0℃),前30d产气占总产气量的90.3%;XRD显示稻草纤维晶体为纤维素Ⅰ型,堆沤预处理和厌氧发酵未改变纤维素的晶型,但略微增加纤维素的结晶度;FT-IR表明:堆沤预处理使聚糖脱聚、纤维素分子键氢键增强和木质素结构部分改变;发酵主要使聚糖脱聚与降解.

Effect of dry digestion on structure changes and biogas production from rice straw

In order to avoid the environmental pollution of open-field burning of rice straw, dry digestion of rice straw is an alternative measure which may produce methane. Composition and structure of raw and treated rice straw were mainly studied by the composition analysis, X-ray and FT-IR analysis, so as to investigate structure changes of rice straw during compost and dry digestion. The results showed that the cumulative biogas yield added up to 278.1mL/g VS added (0℃) during 60days dry digestion and the approximately 90.3% of the biogas yield was obtained in the first 30days of digestion. XRD confirmed that crystalline structure of rice straw fibre was cellulose I which was not changed after compost pretreatment and dry digestion, but the slight change of crystalllinity index happened after pretreatment and digestion. The results of FTIR spectroscopy showed that the deplolymerization and degradation of polysaccharides and the partial modification of lignin structure occurred at compost pretreatment and dry digestion.