A Critical Assessment of Aerobic Composting as part of Solid Waste Management Solutions for Irish Institutions

摘要

This paper is based on the results of an assessment of the potential and constraints of aerobic composting as an effective disposal method for the organic fraction of municipal solid wastes (OFMSW) produced by Irish institutions, namely third level educational institutions. The assessment was done in 2 distinct stages, firstly an examination of Irish institutional waste generation and characterisation by means of a waste management case study of an Irish institution. Secondly an idealisation and benchmarking exercise was carried out on existing Irish and European commercial composting facilities in order to determine the current Irish situation as regards commercial composting and in so doing, offset future potential for the process against current constraints. The organic fraction of the case study wastestream was found to be approximately 56% (1,360 tonnes), with approximately 52% (700tonnes) of this fraction deemed suitable for composting (mainly catering/kitchen waste). These figures were found to correlate with similar Irish institutional data; however it was found that outside Ireland the definition of organic wastes included a broader range of materials which made comparisons difficult. The benchmarking exercise found that Irish composting facilities are currently utilising a reduced level of mechanical pre-processing and post-processing on organic waste materials, resulting in compost products of a significantly lower quality. The absence of composting legislation and a viable compost market were also noted. The paper concluded that the utilisation of aerobic composting of MSW will continue to be financially vulnerable in Ireland while the market for stabilised output material remains weak. However, there remains significant potential for the utilisation of this waste management technique and therefore it may be considered to be a fundamental component for the management of 20-30% of the total institutional wastestream in the future, albeit on a sub-contract basis due to issues surrounding operational feasibility.