@phdthesis{Forbid2012, author = {Forbid, George Teke}, title = {Thermal recycling of plastic waste using pyrolysis-gasification process for energy production}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus-25269}, school = {BTU Cottbus - Senftenberg}, year = {2012}, abstract = {The disposal of mixed waste in landfills, dump sites and open burning without material and energy recovery leads to resource loss, causes health problems, pollution and littering. Increasing energy demand for industrial and domestic application with rising costs due to scarcity motivates a constant search for alternative clean energy sources. Recovering energy from waste presents various incentives e.g. creating jobs, alleviating poverty, combating and mitigating climate change, protecting the environment and reducing dependence on traditional fuels sources. Hence, plastics end up in landfills, surface waters and ocean bed with serious negative impact on terrestrial and aquatic biodiversity. Plastic waste with high calorific value (36-46MJ/kg) occupies the greatest portion of landfill space. Hence, using an appropriate technology to transform waste plastic to a hot gaseous mixture which is burned in-situ produces enormous amount of energy without pollution. Based on this hypothesis, the study objectives accomplished were to: 1.Characterise, quantify and classify waste fractions and plastic components common in MSW by manual sorting 2.Evaluate options for sustainable plastic waste management especially for developing countries 3.Design, construct, test and optimize an appropriate technology that applies pyrolysis and gasification processes to convert non-PVC plastic waste to energy 4.Assess the efficiency of the technology based on the functioning, the engineering, mass and energy analysis including socioeconomic and environmental impacts An integrated methodology involving review of current literature, field and laboratory experiments on mixed waste and plastic waste analysis was used. In addition, the pyrolysis-gasification technology (PGT) was conceptualised, designed, constructed, tested and optimised at BTU Cottbus, Germany; Lagos, Nigeria and Dschang, Cameroon. Field studies involving natural observation, interviews, personal discussions and visits to waste management organisations and disposal sites were conducted in various cities in the three case study countries. A resource-oriented manual sorting using the resource-recovery scavenging approach (RESA) simulating integration of scavenger's activities in waste sorting was conducted at BTU and Lagos. Major results obtained include: •Characterization, quantification and classification of a dry sample of commingled MSW at Cottbus gave major waste fractions in order of decreasing abundance as 23.15\% of residue waste, 19.75\% of paper and cardboards, 17.80\% of plastics, 14.63\% of textiles and diapers, 10.06\% of food waste and 9.55\% of glass. An overall 33.21\% of waste sample is compostable for manure, 52.2\% usable as feedstock in the PG technology and 99.81\% of total sample having a material or energy recovery potential. In Lagos, Nigeria main fractions were 29\% of plastics, 36\% of residue waste, 17\% of soil/sand, 7\% of paper with overall 41\% usable as feedstock in PG technology, 39\% compostable, 3\% of recyclable (metal and glass). Sand can be recovered from the soil/sand fraction for construction. Excluding the sand/soil mixture, 83\% of the total waste sample has potential for material and energy value. •An appropriate technology that applies principles of pyrolysis and gasification to convert non-PVC plastic waste to energy was designed, constructed, tested and optimized with respect to: (i) Successful functioning with conversion of averagely 98.51\% of input constituting of 82.78-98.21\% of charcoal and 96.72-99.27\% of plastic to heat energy (ii) Evaluation of socioeconomic and environmental impacts based on pyrolysis and exhaust gas and ash residue analysis showed absence of VOCs, heavy metals and pollutant organic and inorganic compounds; (iii) Safety and risk assessment to indoor pollution is very low; (iv) Assessment of the WTA and WTP indicated that 94\% of respondents in Lagos, Nigeria and Porto Novo, Benin were willing to accept and pay for this technology. Using the PG technology improves local communities' ability to achieve clean, efficient and safe cooking and heating energy with potential for combine heat power generation.}, subject = {Kunststoffabfall; Vergasung; Pyrolyse; Forstschutz; Energier{\"u}ckgewinnung; Pyrolyse-Vergasung Technologie; Kunststoffabfall; Eind{\"a}mmung des Klimawandels; Ressource-Recovery-Scavenging-Ansatz; Waldschutz; Pyrolysis-gasification technology; Waste plastics and biomass; Climate change mitigation; Resource recovery scavenging approach; Forest protection}, language = {en} }