Characterization of the Effluent Wastewater from Abattoirs for Land Application

Abstract

Meat plant wastewater quality depends on water usage, the type of animal slaughtered, and the amount of rendering or processing that is done on site. In Ontario and Quebec, abattoir wastewater total chemical oxygen demand (TCOD) ranged from 2333 to 8627 mg/L, and suspended solids (SS) from 736 to 2099 mg/L, volatile suspended solids (VSS) represented 80% of SS, and protein content varied from 444 to 2775 mg/L. Nitrogen (N) and potassium (P) averaged 6.0 and 2.3 g/100 g of TCOD, respectively. Ammonia and sulfide levels were well below the 3000 and 100 mg/L toxicity level, respectively. The chemical oxygen demand (COD) of fresh blood is high at 375,000 mg/L compared to the COD of liquid manure at 15,000-30,000 mg/L. The concentration of the wastewater can be greatly affected by the efficiency of blood recovery in the blood pit. Abattoir wastewater contains several million colony forming units (cfu) /100 mL of total coliform, fecal coliform, and Streptococcus groups of bacteria. The presence of these nonpathogenic microbes indicates the possible presence of pathogens of enteric origin such as Salmonella ssp. and Campylobacter jejuni and of gastrointestinal parasites such as Ascaris sp., Giardia lamblia, Cryptosporidium parvum, and enteric viruses. Giardia lamblia and Cryptosporidium parvum are not a concern in poultry wastewater. Pathogens might threaten public health by migrating into groundwater or through traveling off-site by surface water, ORDER REPRINTS wind, or vectors (i.e., animals, birds) etc. Once the treated abattoir wastewater is applied to land, the potential for spread of any pathogens that might remain in the water or sludge varies with the type of crop and soil to which it is applied.

Impacts of Abattoir Waste-Water Irrigation on Soil Fertility and Productivity

“…[38]. Most small and medium abattoirs do not have the tertiary and advance treatment facilities, due to high capital involved in these methods [31,38].…”

“…Wastewater carries diverse microbes that can contaminate the water sources [42], leading to the spread of pathogens from one place another [31]. This may lead to a wide range of diseases such as cholera, typhoid, and dysentery [43].Wastewater discharges from slaughterhouse without proper disinfection, leads to occurrence of meat based infections due to the high populations of E. coli and Salmonella sp.…”

“…A primary treatment includes screening, dissolved air flotation (DAF) and flow equalisation [30]. Pretreatments are processes that remove gross solids; coarse suspended floating matter and primary treatments remove readily settleable solids, most commonly by sedimentation [31]. Pre-treatment methods can be used to minimise the organic load and BOD in the wastewater.…”

Characterization of provincially inspected slaughterhouse wastewater in Ontario, Canada

“…Since slaughterhouse wastewater has high chemical constituents loading and is made up of about 45% soluble and 55% coarse suspended organics (Nunez and Martinez 1999), some municipalities impose surcharges on treating slaughterhouse wastewater. Meat plant wastewater quality depends on water usage, type of animal slaughtered, and the amount of rendering or processing done on site (Mittal 2004). In Ontario and Quebec, Canada, slaughterhouse wastewater COD ranged from 2333 to 8627 mg/L, and SS from 736 to 2099 mg/L, volatile suspended solids (VSS) represented 80% of SS, and protein content from 444 to 2775 mg/L.…”

“…Stebor et al (1990) reported that 400 to 3100 L of wastewater was generated per animal. In general, poultry slaughtering operations use more water, producing lower strength of the wastewater (Mittal 2004).…”