时间和温度对水产养殖固体废弃物水解发酵产酸的影响

在养殖固体废弃物水解发酵18 d和5个温度(25、30、35、40、45℃)的条件下,探讨了固体废弃物水解发酵产生挥发性脂肪酸(Volatile fatty acids,VFA)的效果、VFA的浓度与溶解性化学需氧量(Soluble chemical oxygen demand,SCOD)之间的比例关系、SCOD与总化学需氧量(Total chemical oxygen demand,TCOD)之间的比例关系。结果表明:时间和温度对固体废弃物的水解发酵均有较大影响,当发酵18 d时,水解发酵产生的VFA在试验的第6 d产酸效果最佳,出现最大值2 609.18 mg/L,从试验的第7 d开始VFA开始逐渐下降,至试验的第18 d降至1 899.72 mg/L,VFA的产量只占SCOD含量的很小一部分。在小于35℃范围内,水解发酵产生VFA的含量随着温度的升高而增加,最大VFA的产量在35℃的条件下获得、为2 609.18 mg/L,当温度达到45℃,水解发酵产生的VFA最大值989.69 mg/L,不同温度下的平均水解率(发酵产物中的SCOD与TCOD的比值)随着温度的升高而上升。

Influence of time and temperature on hydrolysis and ferment of aquaculture solid wastes

Laboratory experiment was conducted to investigate the efficiency of the aquaculture solid wastes producing the volatile fatty acids(VFA),the proportion of VFA and soluble chemical oxygen demand(SCOD),SCOD and total chemical oxygen demand(TCOD) at they were hydrolyzed and fermented in 18 days,under the condition of 5 different temperature(25,30,35,40,45℃).The results showed that,time and temperature had a greater impact on the hydrolysis of fermented solid wastes,in the 18 days of fermentation,the best acidogenesis effect was achieved at the 6th,VFA up to 2 609.18 mg/L in maximum and it began to decrease gradually from the 7th day,to 1 899.72 mg/L at the 18th day,while the content of VFA did not account for the content of SCOD highly.Within less than 35℃,the content of VFA increased with temperature increasing,the largest VFA was achieved at 35℃ with 2 609.18 mg/L,when the temperature reached 45℃,the maximum VFA produced by fermentation hydrolysis reached 986.69 mg/L.In different temperatures,the average hydrolysis rate(the ratio of SCOD and TCOD in fermentation products) rose with temperature increasing.