Anaerobic Digestion of Blood from Slaughtered Livestock: A Review

Abstract

Blood from livestock slaughtering imposes a high organic pollution load and risks. If it is discharged untreated to sewer systems, it increases the organic pollution load on wastewater treatment plants by 35–50%. This paper reviews blood anaerobic digestion. It analyzes the quantities, composition, methane potential reported, microbiology, biochemical pathways of blood protein degradation, environmental and health issues, and strategies suggested to manage them during livestock blood anaerobic digestion. Although challenging, anaerobic digestion of blood as a mono-substrate is possible if the culture-reactor system is controlled based on a complete characterization and understanding of the microbial community and its metabolic activities. Co-digestion of blood and other feedstock proceeds well if the mixtures are well designed. Generally, the specific methane yield from digesting blood alone ranges between zero and 0.45 m3 kg−1 protein, whereas for co-digesting blood and other substrates, the yield varies between 0.1 and 0.7 m3 kg−1 volatile solids. More research is required for microbiology and kinetics, the role of adsorbents, reactor configuration, and culture adaptation during anaerobic digestion of blood to better control the process.

Biochemical Methane Potential of Swine Slaughter Waste, Swine Slurry, and Its Codigestion Effect

“…However, in 2012, ocean dumping was prohibited in South Korea. Moreover, there has recently been an interest in utilizing slaughter waste as a substrate for anaerobic digestion [1,5,6]. Around 13 million tons of swine slurry (SS) is produced in South Korea every year [7].…”

Bile acid-binding capacity of peptide extracts obtained from chicken blood hydrolysates using HPLC

“…The discharge of untreated blood into sewage systems increases the organic pollution load in wastewater treatment plants by 35-50%. It also depletes dissolved oxygen in water, enriches nutrient content, induces septic conditions, and propagates microbial and viral diseases (Nazifa et al, 2021). Therefore the use of blood as a source of added-value products is interesting from an economic and environmental point of view.…”

Valorisation of blood protein from livestock to produce haem iron‐fortified hydrolysates with antioxidant activity

“…Blood is the most polluting by‐product generated by the meat production chain in slaughterhouses. With a total nitrogen of around 30 g L −1 , its discharge to water streams can deplete the dissolved oxygen, induce septic conditions, and spread microbial and viral waterborne diseases (Nazifa et al ., 2021). An excess of blood effluents can also cause serious problems in the treatment plant, making its withdrawal necessary.…”