水解液出料和回流对秸秆水解产酸的影响

为了解秸秆两相发酵水解相水解液出料和回流对秸秆水解产酸过程的影响,以打捆麦秸为原料,在中温(37±1)℃]条件下,采用批次进料方式,进行秸秆水解产酸实验.实验设置水解液出料量为排空、排1/2和排1/3,水解液回流频次为不回流、1d回流1次和3d回流1次.结果表明:水解液出料促进了秸秆有机物的水解溶出,水解液出料后秸秆中有机物大量水解溶出,水解液COD、SCOD浓度迅速回升,pH值迅速降低,TVFAs先增加后降低;水解液大出料量更有利于秸秆有机物水解溶出,水解液排空的处理累积COD获得量、TS损失率、半纤维素损失率和纤维素损失率较排1/3的处理分别提高44.45%、25.97%、30.23%和43.34%,排空的处理单位秸秆水解获得COD质量达0.33g COD/g秸秆;水解液回流对秸秆有机物水解溶出并未表现出明显的促进作用,但在实验后期对日产气量及产气中甲烷含量影响明显,3d回流1次的处理累积产气量和产气中甲烷含量均高于不回流和1d回流1次的处理.

Effect of output and reflux of hydrolysate on hydrolysis and acidification process of agricultural straw

Effect of output and reflux of hydrolysate on hydrolysis and acidification process of baling wheat straw were investigated by batch model at (37±1)℃. Ejected the hydrolysate from anaerobic system was good for the dissolving of organic matter of wheat straw. After hydrolysate ejection, more organic matter of wheat straw were dissolved into hydrolysate and content of COD and SCOD increased and pH value decreased rapidly while content of TVFAs increased in the initial stage and than decreased. More hydrolysate ejected from the anaerobic system was benefit for the dissolving of organic matter of wheat straw and amount of COD, total solid losing rate, hemi-cellulose losing rate and cellulose losing rate of the treatment of evacuation of hydrolysate were 44.45%, 25.97%,30.23% and 43.34% higher than that of the treatment of one third hydrolysate ejection. Amount of COD obtained from 1 gram wheat straw was up to 0.33g COD. There was no significantly improvement on the dissolving of organic matter of wheat straw by reflux of hydrolysate. However, daily biogas yield and methane content were increased obviously by reflux of hydrolysate at the end of the experiment. Cumulative biogas yield and methane content of the treatment of reflux hydrolysate once a day were higher than that of the treatment of reflux hydrolysate three times a day and without reflux.