沼液贮存中甲烷和氨气排放规律实验

对猪场沼液贮存中的CH4和NH3排放规律进行研究,使用多点气体采样系统(GSS)对沼液贮存箱中排放的CH4进行采样并输送到TEI55i型甲烷分析仪进行检测,使用大气采样仪和分光光度计对NH3进行间隔采样并分析,同时检测沼液pH值变化.实验结果表明CH4和NH3排放主要集中在贮存前期,其中CH4浓度在贮存的前12天不断增加并达到高峰值,随后呈下降趋势,至第32天CH4的排放量只有1.44 mg/m3;而NH3浓度在贮存前期急剧增加,在后期排放量减少并趋于稳定,至第40天后NH3质量浓度降至3 mg/m3以下.因此对实验中所用猪场发酵后的沼液贮存中的CH4和NH3的有效减排措施分别主要针对贮存的前30天和40天为宜.

Methane and Ammonia Emissions Patterns during Digested Slurry Storage

Measurements of gas emissions (CH4 and NH3) during pig digested slurry storage were carried out by using a dynamic chamber system. Gas emission patterns were obtained. Methane was continuously sampled with gas sampling system (GSS) and analyzed with gas analyzer TEI55i. Ammonia was collected with atmospheric sampling instrument and analyzed with chemical analysis at intervals. The result showed methane and ammonia concentration were both higher at the early days of the storage period. The methane concentration increased in the first 12d, then began to reduce to only 1.44mg/m3 on the 32th day. The ammonia concentration increased sharply in the first 12d, but was not evident in the last two weeks, and reduced to less than 3mg/m3 after the 40th day. Abatement of methane and ammonia emissions should be effective if mitigation options were implemented in the first 30 days and 40 days of digested slurry storage.