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MEKARN Workshop 2009: Livestock, Climate Change and the Environment |
ABSTRACT
A study was carried out to evaluate a waste water treatment method by applying a model of waste water consisted of faeces, uirne and feeds left over directly draining from pig farm into the fish pond and followed a water-hyacinth pond. The investigated parameters used were dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD5), suspension solid (SS), total nitrogen, total phosphorus, total Coliforms and parasitic eggs to measure quality of the waste water in ponds and to compare that of number of the pig per water surface. Samples were taken from six barn blocks of the farm with four replicates by a half month interval for each collection. The results found that the model was rather effective; the quality of the waste water in water hyacinth pond has been met the government standards and reached type A (Vietnam Standard: TCVN 5945 – 2005). The concentration of COD, BOD5, SS, total nitrogen and total phosphorus were significantly reduced of 97,29-97,86%, 96,77-97,68%, 97,57-98,01%, 92,07-94,46% and 95,61-97,76%, respectively as compared with samples directly collected from the farm, except for Coliforms. Increasing fish pond water surface from 105m3 to 227m3/ pig clearly improved water quality.
Water quality of the canals and river surrounded the pig farm area nearly reached type A according to Vietnam Standard TCVN 5942 - 1995.
Key words: pig manure. fish pond, Vietnam standard, water-hyacinth pond, waste water treatment