不同碳源培养胶球藻C-169净化糖蜜酵母废水

本项目系统研究了三种碳源(CO_2、醋酸和甘油)添加到预处理后的糖蜜酵母废水,在藻菌共生条件下培养胶球藻C-169的生长情况及强化废水净化效果。结果表明,与通入空气相比,补充2%CO_2,能显著提高细胞的平均比生长速率、生物质产率,分别是通入空气的6.49、10.4倍,显著提高了对脱色废水的总氮、总磷和氨氮去除率(p0.05),但降低了废水COD(化学需氧量)去除率。研究发现胶球藻C-169能够利用甘油作为其生长的碳源,在0～20 g/L甘油浓度时,随着甘油浓度的提高,细胞生长速率增大,总氮、总磷去除率提高,并在20g/L时获得最高生物量干重达到8.80g/L,平均比生长速率是不添加甘油的2.07倍,生物量产率达0.70 g/(L·d)。甘油浓度在15 g/L以上时,总氮、总磷去除率分别高达85%、95%以上,极显著地提高了废水COD(p0.01)。添加1～4g/L醋酸,均会抑制胶球藻C-169的生长,降低废水净化效果。因此在使用C-169净化COD较高的废水时,可添加甘油作为其生长的碳源。

Cultivation of Coccomyxa subellipsoidea C-169 using Different Carbon Sources to Purify Molasses Yeast Wastewater

In this study, three carbon sources (CO2, acetic acid and glycerol) were added to the pretreated molasses wastewater, and then the growth of Coccomyxa subellipsoidea C-169 in a symbiotic algal-bacterial system cultured in such enhanced wastewater and the outcome of such an enhancement were examined. Compared with the results related to aeration with air, supplementation with 2% CO2 could significantly increase the average cell growth rate and biomass yield by 6.49 and 10.4 times, respectively, and remarkably increased the total nitrogen, total phosphorus and ammonia nitrogen (p<0.05) but reduced the removal rate of COD (chemical oxygen demand) of wastewater. It was found that Coccomyxa subellipsoidea C-169 could use glycerol as its carbon source. At a glycerol concentration within 0~20 g/L, an increase of glycerol concentration led to an increased cell growth rate, and total nitrogen and total phosphorus removal rates. At 20 g/L, the highest dry weight of biomass reached 8.80 g/L, the average specific growth rate was 2.07 times as high as that without glycerol (the biomass yield, 0.70 g/(L?d). When the glycerol concentration was above 15 g/L, the removal rates of total nitrogen and total phosphorus were over 85% and 95%, respectively, which significantly increased the wastewater COD (p<0.01). Addition of 1~4 g/L acetic acid would inhibit the growth of Coccomyxa subellipsoidea C-169 and reduce wastewater purification efficiency. Therefore, when C-169 is used to purify wastewater with a high COD, glycerin can be added as a carbon source for its growth.