Fangueiro David, Coutinho Joao, Chadwick David, Moreira Nuno, Trindade Henrique
Instituto Superior de Agronomia, UIQA, TU Lisbon, Tapada da Ajuda, 1349-017- Lisboa, Portugal.
J Environ Qual. 2008 Oct 23;37(6):2322-31. doi: 10.2134/jeq2007.0330. Print 2008 Nov-Dec.
Storage of cattle slurry leads to emissions of methane (CH(4)), nitrous oxide (N(2)O), ammonia (NH(3)), and carbon dioxide (CO(2)). On dairy farms, winter is the most critical period in terms of slurry storage due to cattle housing and slurry field application prohibition. Slurry treatment by separation results in reduced slurry dry matter content and has considerable potential to reduce gaseous emissions. Therefore, the efficiency of slurry separation in reducing gaseous emissions during winter storage was investigated in a laboratory study. Four slurry fractions were obtained: a solid and a liquid fraction by screw press separation (SPS) and a supernatant and a sediment fraction by chemically enhanced settling of the liquid fraction. Untreated slurry and the separated fractions were stored in plastic barrels for 48 d under winter conditions, and gaseous emissions were measured. Screw press separation resulted in an increase of CO(2) (650%) and N(2)O (1240%) emissions due to high releases observed from the solid fraction, but this increase was tempered by using the combined separation process (CSP). The CSP resulted in a reduction of CH(4) emissions ( approximately 50%), even though high emissions of CH(4) (46% of soluble C) were observed from the solid fraction during the first 6 d of storage. Screw press separation increased NH(3) emissions by 35%, but this was reduced to 15% using the CSP. During winter storage greenhouse gas emissions from all treatments were mainly in the form of CH(4) and were reduced by 30 and 40% using SPS and CSP, respectively.
牛粪浆的储存会导致甲烷（CH₄）、一氧化二氮（N₂O）、氨（NH₃）和二氧化碳（CO₂）的排放。在奶牛场，由于牛舍饲养和禁止向农田施用牛粪浆，冬季是牛粪浆储存最关键的时期。通过分离进行牛粪浆处理可降低牛粪浆的干物质含量，并且在减少气体排放方面具有相当大的潜力。因此，在一项实验室研究中，对冬季储存期间牛粪浆分离减少气体排放的效率进行了研究。获得了四个牛粪浆组分：通过螺旋压榨分离（SPS）得到一个固体组分和一个液体组分，以及通过对液体组分进行化学强化沉降得到一个上清液组分和一个沉淀物组分。未处理的牛粪浆和分离出的组分在冬季条件下于塑料桶中储存48天，并测量气体排放。由于从固体组分中观察到高释放量，螺旋压榨分离导致CO₂排放增加（650%）和N₂O排放增加（1240%），但通过使用联合分离工艺（CSP），这种增加得到了缓解。CSP导致CH₄排放减少（约50%），尽管在储存的前6天从固体组分中观察到高CH₄排放（可溶性碳的46%）。螺旋压榨分离使NH₃排放增加了35%，但使用CSP可将其降至15%。在冬季储存期间，所有处理的温室气体排放主要以CH₄的形式存在，使用SPS和CSP分别减少了30%和40%。
