Within the aquaculture industry in NL, plastic wastes have been disposed of via landfill or incineration. These environmentally unsustainable options are forced upon industry due to lack of municipal/private recycling infrastructure. The industry has concerns over watershed impacts and the recovery of products through reprocessing is desired. Approximately 45 metric tonnes of polyethylene and 50 metric tonnes of polypropylene bags will be generated as waste in aquaculture operations in NL in 2016. The disposal and/or reprocessing of plastic feed bags is limited due to contamination with fish feed. Options for reprocessing include aggressive chemical methods and thermal methods (hydrocracking, partial oxidation, and pyrolysis).
Pyrolysis (thermally treating without oxygen) uses lower temperatures, produces a liquid fuel, and does not require additional chemicals. The yield of oil is a function of the feedstock (polyethylene pyrolysis can yield up to 90+ wt% of oil). There have been no studies on pyrolysis of waste plastic fish bags and it is unknown if feed contamination of the bags impacts produced fuel quality. In this study, we will determine the yield of oil, gas, and solids from the pyrolysis by varying parameters including feed contamination. The study will identify if pre-processing is required prior to pyrolysis, the interaction of the operating conditions on oil quality/yield, and characterize the oil for fuel quality. Ultimately this study will determine if pyrolysis of fish bags is a viable reprocessing option for production of a fuel for use on site and solve a major waste management issue in fish processing.
See the full report here.