Blanes-Vidal Victoria, Hansen Martin N, Sousa Patricia
Faculty of Engineering. Univ. of Southern Denmark, Niels Bohrs Alle 1, 5230, Odense, Denmark.
J Environ Qual. 2009 May 20;38(4):1518-27. doi: 10.2134/jeq2008.0412. Print 2009 Jul-Aug.
Swine (Sus scrofa) slurry stored in open storages is a source of airborne contaminants. A customary practice for ammonia and odor control consists of covering the surface of the slurry with floating materials, such as straw. Although straw covers have been proven to generally reduce gaseous emissions, more knowledge is needed regarding how age, moisture content, and microbiological development of the straw cover affect the emissions of odor and odorants to develop recommendations for the practical use of straw covers. This study compiles data on odor concentration and odorants above swine slurry covered by straw of different ages and moisture contents, during a 9 wk laboratory scale study. The results showed that aged straw covers significantly reduced emissions of ammonia (by 99%), dimethyl sulfide (by 81%), phenol (82%), p-cresol (by 95%), skatole (by 98%), and benzylalcohol (by 97%), while no significant differences were found between uncovered and covered slurry for emission of odor, hydrogen sulfide, volatile fatty acids, dimethyl disulfide, and indole. The moisture content of the straw cover neither affected emissions of odor nor odorants. This study suggests that the main mechanism for odor and odorants emission reduction from straw covered slurry is as a physical barrier and not as a biofilter. However, the reduction in emissions of specific gases (such as ammonia, dimethyl sulfide, p-cresol, and benzyl alcohol) appears to be also caused by the straw cover acting as a biofilter.
储存在开放式储存设施中的猪（野猪）粪便浆是空气污染物的一个来源。控制氨和气味的常规做法包括用诸如稻草等漂浮材料覆盖粪便浆表面。尽管已证明稻草覆盖通常可减少气体排放，但对于稻草覆盖物的老化程度、水分含量和微生物生长如何影响气味和气味剂的排放，还需要更多了解，以便为稻草覆盖物的实际应用制定建议。在一项为期9周的实验室规模研究中，本研究收集了不同老化程度和水分含量的稻草覆盖的猪粪便浆上方的气味浓度和气味剂数据。结果表明，老化的稻草覆盖物显著减少了氨（减少99%）、二甲基硫醚（减少81%）、苯酚（减少82%）、对甲酚（减少95%）、粪臭素（减少98%）和苯甲醇（减少97%）的排放，而对于未覆盖和覆盖的粪便浆，在气味、硫化氢、挥发性脂肪酸、二甲基二硫醚和吲哚的排放方面未发现显著差异。稻草覆盖物的水分含量既不影响气味排放，也不影响气味剂排放。本研究表明，稻草覆盖的粪便浆减少气味和气味剂排放的主要机制是作为物理屏障，而非生物过滤器。然而，特定气体（如氨、二甲基硫醚、对甲酚和苯甲醇）排放的减少似乎也是由稻草覆盖物作为生物过滤器所致。
