光照度对酶解秸秆料液光合产氢的影响

Effects of light intensity on photohydrogen production from straw enzymatic hydrolysates

为了提高光合细菌的产氢能力和光能转化效率,该文以高粱秸秆超微粉体酶解48h料液为光合产氢碳源,在反应温度30℃,光合混合菌群接种量为体积分数20%的条件下,研究了光照度对光合产氢过程中累积产氢量、产氢速率和光能利用效率的影响。结果表明:当光照度低于5000lx时,光合细菌的累积产氢量和光合产氢速率随着光照度的增大而增大,超过5000lx时累积产氢量和产氢速率反而减小,说明光合细菌的光合产氢存在一个类似于植物光合作用的光饱和点,当光照度超过光饱和点时出现光抑制现象。反映光能利用效率的光能增量影响系数的最大值出现在>1000～3000lx之间,说明该试验条件下从能量转换角度采用此区间的光照度比较合适。

In order to improve the hydrogen production ability and light conversion efficiency of photosynthetic bacteria, , effects of light intensity on cumulative hydrogen production, hydrogen production rate and light conversion efficiency in the photohydrogen production from sorghum straw enzymatic hydrolysates within 48 h were investigated under the reaction temperature 30℃ and the mixed culture of photosynthetic bacteria inoculums 20%（volume fraction）. The results showed that cumulative hydrogen production and hydrogen production rate increased with the increasing light intensity when it was lower than 5 000 lx, but decreased when it was higher than 5 000 lx. This phenomenon was similar with the light saturation point of plant, photoinhibition occurred when the light intensity were higher than light saturation point. The maximum influence coefficient of light increments occurred when the light intensity increased from 1 000 lx to 3 000 lx, which indicated the light intensity was more appropriate in this range from the point of light conversion efficiency.