Two primary concerns of dairies that store manure wastewater in anaerobic ponds are greenhouse gas emissions and unpredictable nutrient availability after applying it to forage crops. Solid-liquid separation of dairy manure wastewater with chemical coagulants significantly reduces the fraction of organic matter stored in anaerobic conditions. However, the effect of coagulants on methane emissions from ponds and nutrient availability following field application are not well understood. In this experiment, several metal salts and organic polymers were used to coagulate dairy manure wastewater for separation into solid (floc) and liquid (effluent) fractions. The coagulants tested were ferric sulfate, ferric chloride, polyaluminum chloride, Superfloc C-569, and chitosan. An anaerobic incubation of manure effluent to simulate liquid manure storage and an aerobic incubation of manure floc-amended soil to simulate field application were conducted with analysis of GHGs and carbon and nitrogen transformations. The treatment of chemically separating organic matter from manure wastewater effectively eliminated methane emissions under anaerobic conditions in the lab. In the solid manure fraction, organic carbon was stabilized in the chemically separated flocs and, apart from flocs produced with ferric iron, nitrogen mineralization was reduced as well. Carbon dioxide emissions were also reduced from the flocs applied to soil compared to untreated manure solids. This article is protected by copyright. All rights reserved.

中文翻译：

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使用化学混凝减少温室气体排放并稳定奶牛粪中的养分

将粪便废水储存在厌氧池中的奶牛场的两个主要问题是温室气体排放和将其应用于饲料作物后不可预测的养分可用性。用化学混凝剂对乳粪废水进行固液分离，显着降低了储存在厌氧条件下的有机物的比例。然而，混凝剂对池塘甲烷排放和田间应用后养分有效性的影响尚不清楚。在这个实验中，几种金属盐和有机聚合物被用于凝结乳粪废水，以分离成固体（絮凝物）和液体（流出物）部分。测试的混凝剂是硫酸铁、氯化铁、聚合氯化铝、Superfloc C-569 和壳聚糖。通过对 GHG 和碳和氮转化的分析，对粪便流出物进行厌氧培养以模拟液体粪便储存和粪便絮状改良土壤的有氧培养以模拟田间应用。从粪便废水中化学分离有机物的处理有效地消除了实验室厌氧条件下的甲烷排放。在固体粪便部分，有机碳稳定在化学分离的絮凝体中，除了用三价铁产生的絮凝体外，氮矿化也减少了。与未经处理的粪便固体相比，应用于土壤的絮凝物也减少了二氧化碳排放。本文受版权保护。版权所有。