Solid waste generation is drastically increasing in the world. Changes in lifestyle, rapid urbanization and swift developments happening in the society are among the major causes of this substantially significant increase in waste generation. Improper waste management/disposal leaves negative effects on the environment (air and water quality) and health of living being (human, animals, marine life). Especially, open waste dumps and unmanaged waste landfills are considered as potential source of greenhouse gases emissions into the atmosphere. Also, due to mismanagement and mishandling enormous amounts of waste end up in water (lakes, rivers and oceans) causing immense issues to marine life.
In 2016, estimated amount of solid waste generated in the world was 2.10 billion tons which is projected to grow to 3.40 billion tons in 2050. In 2016, East Asia and Pacific, Europe and Central Asia and South Asia were top three Regions in solid waste generation with 468 millions tons, 392 million tons and 334 million tons per year, respectively. In South Asia, Sub-Saharan Africa and Middle East & North Africa of the total municipal solid waste (MSW) generated in these Regions 75 %, 69 % and 52.7 % respectively ends up in open dumps. In Latin America & Caribbean, North America and East Asia & Pacific of the total MSW generated in these Regions 68.5 %, 54.3 % and 46 % respectively is transferred to landfills. Currently, about 5 % of global greenhouse gas emissions is generated by solid waste management sector .
Waste Hierarchy and shift from Linear Economy to Circular Economy are among the major approaches which need to be followed more effectively in practice to achieve the goals of proper waste management and recovery of value from waste. Waste Hierarchy addresses the issue of waste management to be solved through prevention, reduction, recycling, recovery and disposal of waste (with previous aspects as most preferred and the later ones as least preferred). In Circular Economy based Waste to Value solution, non-recyclable waste, particularly different streams of MSW such as household waste, commercial and industrial/institutional waste, construction and demolition waste, biowaste, forestry waste and manure and other related waste streams can be processed in mechanical-biological and incineration (combustion, gasification, pyrolysis) system to recover maximum possible value out of waste in highly efficient and environmentally sound manners. In the mentioned system, MSW/mixed waste is first classified into various resource streams such as recycling material (metal, glass, inert as construction material and some other waste components), biofraction (biodegradable waste) and refuse-derived fuel (RDF)/solid recovered fuel (SRF) i.e. mixture of high calorific containing waste components such as plastic, paper and cardboard, textile and rubber etc. Each segregated material stream is further treated/utilized in respective process to recover maximum possible value out of it. Recycling material (metal, glass, inert as construction material and some other waste components) is recycled in the respective facility/industry, biofraction (biodegradable waste) is treated in anaerobic digestion process producing biogas and RDF/SRF is incinerated (combustion, gasification, pyrolysis) producing energy. A simplified schematic of Circular Economy based Waste to Value solution is given below.
Figure: Circular Economy based Waste to Value process (simplified schematic)
Chemitec Consulting Oy possesses expertise in developing from process concept to complete solution for Circular Economy based Waste to Value system and offers its services in performing detailed Techno-economic, feasibility study, basic design and pre-engineering, selection of best available technology and project management in the field.
 Silpa Kaza, Lisa Yao, Perinaz Bhada-Tata, and Frank Van Woerden. What a Waste 2.0 A Global
Snapshot of Solid Waste Management to 2050. World Bank Group. Available at:
https://openknowledge.worldbank.org/handle/10986/30317. Assessed on 26.10.2020