Composting and vermicomposting waste paper sludge.
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
large scale experiments with the aim of optimising these processes with 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.