Two enhanced biological phosphorus removal (EBPR) sequencing batch reactors (SBR1, SBR2) treating liquid dairy manure were operated with the same hydraulic retention time (HRT) and solids retention time (SRT), but with different aeration cycles. During eight months of operation, both SBRs achieved good removal of total phosphorus (P) (TP; 56.8 and 73.
View Article and Find Full Text PDFSynthetic oral contraceptives (SOCs) are a group of compounds with progestagenic and/or androgenic activities, with some also possessing estrogenic activities. Recent research has documented that some of these emerging contaminants have adverse effects on aquatic organisms at very low concentrations. To facilitate the evaluation of their latent risks, published works on their occurrence and fate in the environment are reviewed.
View Article and Find Full Text PDFThis study was conducted to determine the potential for reducing ammonia (NH3) emissions from manure deposited on the floor of a naturally ventilated free stall barn by mid-lactation dairy cows fed reduced or normal N diets. Two crude protein (CP) diets (178 g kg(-1) [high] and 159 g kg(-1) [low] dry matter ), were used. The diets were fed to 48 Holstein cows in a replicated crossover design with two pens per diet.
View Article and Find Full Text PDFA continuously operated, intermittently fed reactor (fermenter) system with a 2-d solids retention time was proposed for supporting biological nutrient removal from liquid dairy manure. The first objective of this study was to select a material with high fermentation potential to be used as the fermenter feed. Primary sludge, liquid separated dairy manure, and flushed dairy manure were investigated for their fermentation potential.
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