不同环境温度下沼气工程厌氧罐内料温研究

Research on the Temperature in Anaerobic Tank for Biogas Project Under Different Ambient Temperature

厌氧罐的池容产气率直接受料温的影响,而料温随着环境温度的变化而变化。文章利用沼气锅炉燃烧沼气工程自产沼气来为厌氧罐内料液提供达到指定温度所需热量的方式,根据能量和质量守恒定律,来研究不同环境温度下沼气工程产生连续稳定富裕产气量所需的厌氧罐最合理料温。研究结果表明,同一料温下,环境温度越高,富裕产气量越大;同一环境温度下,随着料温的增长,系统富裕产气量分别在35℃和55℃出现了峰值。从富裕产气量的角度来看,经济温度在55℃左右,而中低温发酵经济温度为35℃。但从富裕产气量占总产气量的百分比上来看,在不同环境温度下,35℃和55℃料温各有高低。考虑到料温稳定性、沼气热值、设备造价及沼渣再利用等因素,不同环境温度下料温宜全部选择35℃,其富裕产气量维持在每天66~138 m^3范围内。

The volumetric biogas production rate is directly affected by the material temperature in the fermentation tank, and which will be changed with the change of ambient temperature. In this paper, the rational material temperature inside the fermentation tank were studied by heating the fermentation material with biogas fueled boiler to achieve a specified tem- perature, producing stable and affluent biogas under different ambient temperature. We call the remaining biogas as rich biogas after biogas consume by the boiler. The results showed that, at the same material temperature, the higher the ambi- ent temperature, the more the rich biogas produced ; at the same ambient temperature, with the increase of material temper- ature by the biogas boiler, the rich biogas production appeared peak value at 35℃ and 55℃. From point view of rich biogas quantity, the economic temperature was 55 ℃. But considering the factors of material temperature stability, biogas calorific value, equipment cost and biogas residue recycle, 35% of material temperature should be best choice at different ambient temperature, under which the rich gas production kept range within 66.4 ～ 138.0 m3 for the tested 200 m3 CSTR reactor.