|Haylock, Randall - Iowa State University|
|Rosentrater, Kurt - Iowa State University|
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/19/2016
Publication Date: 4/2/2016
Citation: Garcia, R.A., Nieman, C.M., Haylock, R.A., Rosentrater, K.A., Piazza, G.J. 2016. The effect of chicken blood and its components on wastewater characteristics and sewage surcharges. Poultry Science. 95(8):1950-1956. doi: 10.3382/ps/pew114.
Interpretive Summary: All food processing plants produce wastewater which contains substances that must be removed before the water can be released back to the environment. These substances are usually not toxic chemicals, but rather they are simply substances such as fat or protein originating from the food that is being processed. When a food processing plant releases wastewater to a public sewer system, they must pay a fee which is based on the concentrations of these substances in their wastewater. For chicken processing plants, a large proportion of the undesirable substances originate with chicken blood entering the water. Modern US chicken processing plants take steps to prevent most of the blood from entering the wastewater; they collect it and it is hauled away for other uses. A portion of the blood, however, does end up in the water, and consequently reduces the water quality while increasing the facility’s sewage fees. Processors can take measures to further limit the amount of blood that reaches the water, but this will normally require additional expenses. With currently available information, it is hard for a processor to evaluate the potential benefit of an investment in improved blood collection. This project overcomes the difficulty by measuring the water pollution properties of chicken blood, and by providing methods to calculate the effect of improved blood collection on sewage fees. It is anticipated that these results will assist poultry facility operators in making rational decisions regarding investments in water pollution control measures.
Technical Abstract: Local wastewater treatment authorities charge non-residential customers, in part, based on measurements which indicate the pollutant load in the customer’s wastewater. Blood has long been recognized as the most potent contributor to pollutant loads in chicken processing plant wastewater. Quantification of the impact of blood on wastewater characteristics and sewage surcharges is hindered by lack of information on specific characteristics of chicken blood, and by the highly variable methods used by local authorities for calculating surcharges. In this study, the most commonly used wastewater characteristics are determined for whole chicken blood as well as its individual components. The characteristics measured include biochemical oxygen demand, chemical oxygen demand, total suspended solids, fats oil and grease, total Kjeldahl nitrogen, ammonia and total phosphorus. Sewage surcharge calculation methods were collected from 71 local wastewater authorities. The results show all components of the blood to be extremely high-strength pollutants. The impact of blood on sewage surcharges is shown to be highly variable depending on the rates applied by the local authority.