Composting and vermicomposting waste paper sludge

Abstract

Increasing legislative and economic pressure to find more sustainable methods of organic waste management has fuelled innovation in biological treatment technology. By-products of paper manufacturing industries provide a large source of organic waste, which is known to have a high environmental impact. This waste paper sludge has been shown to be amenable to biological treatment. Recent research has confirmed that windrow-composting and vermicomposting techniques have potential to treat these wastes and share many economic and environmental benefits. Many authors have suggested that sludge specific composting methods need to be developed and this research aims to provide fundamental data in this respect. The treatment of specific waste paper sludges was investigated through small and larges calee xperimentsw ith the aim of optimising thesep rocessesw ith minimal intervention. Identical samples of a selected waste paper sludge feedstock were used in large scale investigations into the application of each composting technique, and the performance of each process and resulting products was evaluated. Windrow composting and vermicomposting were found to stabilise and enhance waste paper sludge in very different ways, producing unique products. In terms of processing, windrow composting resulted in more rapid rates of stabilisation and although the performance of the vermicomposting process was less effective in these respects, it afforded additional benefits as a treatment of waste paper sludge. Both processes were found to stabilise and enhance waste paper sludge but the selection of one system or the other will depend largely on the objectives of the project and the criteria required of the finished product.