Commercialization in the meat-processing industry has emerged as one of the major agrobusiness challenges due to the large volume of wastewater produced during slaughtering and cleaning of slaughtering facilities. Slaughterhouse wastewater (SWW) contains proteins, fats, high organic contents, microbes, and other emerging pollutants (pharmaceutical and veterinary residues). It is important to first characterize the wastewater so that adequate treatment techniques can be employed so that discharge of this wastewater does not negatively impact the environment. Conventional characterization bulk parameters of slaughterhouse wastewater include pH, color, turbidity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), and coliform counts. Characterization studies conducted have revealed the effects of the pollutants on microbial activity of SWW through identification of toxicity of antibiotic-resistant strains of bacteria. Due to the high-strength characteristics and complex recalcitrant pollutants, treatment techniques through combined processes such as anaerobic digestion coupled with advanced oxidation process were found to be more effective than stand-alone methods. Hence, there is need to explore and evaluate innovative treatments and techniques to provide a comprehensive summary of processes that can reduce the toxicity of slaughterhouse wastewater to the environment. This work presents a review of recent studies on the characterization of SWW, innovative treatments and technologies, and critical assessment for future research.

Produced water from development of oil and gas resources - especially development of unconventional resources using hydraulic fracturing - requires management to avoid unintended environmental impacts. The recent rapid expansion of development in Pennsylvania's Marcellus Shale formation has led to significantly higher volumes of produced water requiring management. Conventional produced water management frequently involves treatment at centralized brine treatment plants that provide partial treatment and release into surface waters through NPDES permits that are exempt from salt limits, although use of this treatment option has declined from 3.18 to 2.27 Mbbls from 2006 to 2012. Reuse of conventional produced water increased significantly in 2012 (to 43% of the total volume). Although representing a small fraction of total water under management (less than 10%), use of surface-discharging publically owned treatment plants that do not remove salt has increased for conventional produced water (from 0.35 Mbbls in 2006 to 0.77 Mbbls in 2012). Unconventional (shale gas) produced water is predominately managed through recycling and reuse. Use of surface-discharging plants significantly declined between 2006 and 2012 (from 5.81 Mbbls to 0.62 Mbbls), while underground injection and treatment at facilities that return treated water for reuse have both increased.