The greenhouse gas and energy balance of different treatment concepts for bio-waste

Abstract

The greenhouse gas (GHG) and energy performance of bio-waste treatment plants been investigated for three characteristic bio-waste treatment concepts: composting; biological drying for the production of biomass fuel fractions; and anaerobic digestion. Compared with other studies about the environmental impacts of bio-waste management, this study focused on the direct comparison of the latest process concepts and state-of-the-art emission control measures. To enable a comparison, the mass balance and products were modelled for all process concepts assuming the same bio-waste amounts and properties. In addition, the value of compost as a soil improver was included in the evaluation, using straw as a reference system. This aspect has rarely been accounted for in other studies. The study is based on data from operational facilities combined with literature data. The results show that all three concepts contribute to a reduction of GHG emissions and show a positive balance for cumulated energy demand. However, in contrast to other studies, the advantage of anaerobic digestion compared with composting is smaller as a result of accounting for the soil improving properties of compost. Still, anaerobic digestion is the environmentally superior solution. The results are intended to inform decision makers about the relevant aspects of bio-waste treatment regarding the environmental impacts of different bio-waste management strategies.

Economic efficiency of processing biodegradable waste in dry anaerobic digestion and composting technologies under the Polish market conditions

“…From an environmental point of view, the properly functioning biogas plants generating energy from renewable energy sources have a significant advantage over aerobic stabilization/composting of biodegradable waste [21]. However, the results of the economic analysis of anaerobic digestion and aerobic stabilization show that the profitability of both processes to a large extent depends on the situation on the energy market.…”

“…This study analyzed two alternative sources of industrial and agricultural wastes to fill the second digester. In the first option the feeding of 11 278 t/year of industrial wastes into the digester was assumed to reach the required level of dry matter (35%, after adding fresh water and/or leachate) as well as an appropriate carbon to nitrogen ratio (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). The waste would be acquired from two sites located at a distance of 12 km and 35 km from the plant.…”

Informal sector: A complex link to transform solid waste management in a circular economy system

“…Need more work to promote environmentally sound waste disposal and support greenhouse gas mitigation by different means such as food loss, organic waste diversion, waste reduction, and the acceptance of treatment as well as disposal technologies that collect biogas and landfill gas (Ortner et al, 2013).…”

Assessment of biowaste losses through unsound waste management practices in rural areas and the role of home composting

“…Home composting is a suitable treatment option for organic wastes such leftovers of raw fruit and vegetables from the technical and environmental point of view, as documented by Colon et al (2010). Composting, biomass fuel production, and anaerobic digestion contributes to GHG emission savings, and so they sound as valid alternatives to be considered for biowaste treatment (Ortner et al 2013). Andersen et al (2010) found that GHG emission of home composting units (cone-shaped, made of recycled polyethylene and polypropylene) is similar in magnitude as for centralized composting plants in Denmark.…”