One of the oldest and most enduring challenges to civilization has been the protection of humans and their livestock from infectious diseases. Transmission risks arising from diseased animal carcasses, inedible slaughter materials and odorous rotten food have always alarmed societies, who have responded primarily with burning and burial in order to destroy or remove health risks. The medieval practice of cooking these materials to melt and recover the fats for food and fuel evolved into the modern industry of rendering, which developed, in addition to the valuable fat, dehydrated meat and bone meal products for the livestock industry. These eventually became a major source of protein for the feed industry and a vital source of income for meat processing and rendering industries.
The emergence of new highly resistant pathogenic agents which survive the rendering processes, thereby creating potentially infectious meat meal, has led to global regulations banning risk materials from use for animal feed, creating major health, environmental and economic challenges. In addition, new regulations are being implemented internationally regarding banning “catering waste” originating in commercial food institutions as animal feed for swine and poultry. These regulatory developments are creating massive tonnage of risk materials imposing serious negative costs on the agricultural economy. The societal need for innovative technologies to provide solutions which are alternatives to destructive incineration and burial, and offer long term economic solutions, is the focus of thermal hydrolysis bio-refining.
Of the CFIA (Canadian Food Inspection Agency) approved methods for destruction and disposal (incineration, cement kiln incineration, alkaline hydrolysis, thermal hydrolysis, landfill) only thermal hydrolysis contributes the most to a sustainable environment. Thermal hydrolysis can produce safe and valuable organic nutrients that can be recycled. Pollution of air (incineration), land (landfills) and water (chemical leachates) is avoided. In addition, greenhouse gas emissions (methane) and noxious odors from landfills are reduced or eliminated.
Thermal hydrolysis followed by fractionation can result in the development of a wide range of nutrient products. Some fractions can be used as feedstock for anaerobic digestion and methane biogas production. The methane can be used directly for co-generation of green power or as a biofuel for hot water and steam boilers. As a replacement for fossil fuels, this product will also generate economic value from marketable carbon credits, now being traded internationally. Other fractions can be used in the development of liquid and solid organic fertilizers for food crops. Canada has now joined 40 other countries with national organic food regulations ,which creates a need for consistent quality organic fertilizers. Output materials from thermal hydrolysis, such as hydrolyzed meat and bone, meet the criteria for approved substances, which can be used in certified organic crop production markets. A cost-effective organic liquid fertilizer can be used in organic hydroponic greenhouse and viniculture operations. Limits on chemical fertilizers due to negative environmental impacts on water sheds and soil health is creating a new turf grass market opportunities, particularly in applications such as golf courses.
Finally, nutrient fractions have the potential to be used for soil reclamation and remediation of contaminated soils. The large industrial energy projects in North America, both at the oil sands and the traditional thermal coal fields, have major mandated soil reclamation requirements. This creates a need for nutrients to accelerate restoration of the land. In addition, the conventional oil and gas sectors have continuing remediation activities requiring organic nutrients. Continuing destruction and depletion of any organic nutrients from the biosphere is environmental folly. The international community now has the opportunity and technology to transform negative cost and inedible organic materials, including SRM’s, into many new safe, valuable and desirable commercial and industrial products, emulating past decades of research support for creating value-added meat products from the edible portions of the carcass. This development would increase the stature of the meat processing industry, and provide the OIE nations a safe environmental and economic solution for disposal of growing volumes of carcasses and other animal by-products.
