A research-cum-demonstration plant was set up at Nagpur, Maharashtra for conversion of waste plastics into liquid fuel. The process adopted is based on random de-polymerization of waste plastics into liquid fuel
in presence of a catalyst. The entire process is undertaken in closed reactor vessel followed by condensation, if required. Waste plastics while heating upto 2700 C to 3000 C convert into liquid-vapour state, which is
collected in condensation chamber in the form of liquid fuel while the tarry liquid waste is topped-down from the heating reactor vessel. The organic gas is generated which is vented due to lack of storage facility. However, the gas can be used in dual fuel diesel-generator set for generation of electricity. The process includes the steps shown ahead:
Environment related observations during the process
❯ There are no liquid industrial effluents and no floor washings as it is a dry process.
❯ There are no organized stack and process emissions.
❯ Odour of volatile organics has been experienced in the processing area due to some leakages or lack of proper sealing
❯ Absolute conversion of liquid-vapour was not possible into liquid, some portion of gas (about 20%) is connected to the generator. However, the process will be improved in full-scale plant.
❯ PVC plastics waste is not used and if used, it was less than 1%. In case PVC is used, the chlorine can be converted into hydrochloric acid as a by-product.
❯ The charcoal (charcoal is formed due to tapping of tarry waste) generated during the process has been analysed and contain heavy metals, poly aromatic hydrocarbon (PAH) which appears to be hazardous in nature. The source of metals in charcoal could be due to the presence of additives in plastics and due to multilayer and laminated plastics.
❯ Monitoring of process fugitive emissions in the work area as well as emissions from the engines/diesel generator sets is necessarily required (where this liquid fuel is used) for various parameters such as CO, HCl,
Styrene, Benzene, VOCs.