A solution to growing stockpiles of glass waste at landfill sites on New Zealand“s South Island may be a step closer.
With funding from the Department of Labour, the Zero Waste New Zealand Trust is …
A solution to growing stockpiles of glass waste at landfill sites on New Zealand“s South Island may be a step closer. With funding from the Department of Labour, the Zero Waste New Zealand Trust is to undertake a feasibility study on uses for waste glass in the island. The study will look at the volumes of glass going to waste and potential secondary industries. “The Trust is delighted to undertake this study that we hope will assist the move towards South Island regional co-operation on this type of waste challenge,” says Zero Waste NZ Trust chief executive, Jo Knight. Large stockpiles of glass have built up in the South Island as distance from markets has made transporting the waste glass to Auckland uneconomic. John Cocks of Southern Recycle in Timaru, although not contracted to handle glass in the region, says that finding a use for it will not be easy. During his years in the recycling business he has seen various attempts to recycle the glass. “Some have tried in more recent years to develop a use for it, such as crushing it and using it in sandblasting and a company in Christchurch was looking at making tiles with it,” he said, adding that it was also considered as a possible replacement for shingle as a filter medium in roading, he said. “None of these have taken off and if they do they don“t use enough of it. But as technology advances over time we will find a way to treat it and reuse it.” “Recent announcements have highlighted the fragile nature of the glass issue and may provide us with the catalyst for an initial model for South Island co- operation,” Ms Knight said. “Dotted around the South Island, particularly in the lower south, there are stockpiles of glass which although inert, are unsightly and offer a real opportunity for a trial.” On 1 January 2005 there were big reductions in the price offered for cullet with more reductions due for clear cullet. This will undoubtedly lead to a wider area of stockpiling, she said. One option under investigation is glass crushing: the resulting sand is in short supply in many areas. The resource consent process for future sand mining has become contentious in some parts of the North and may become an increasing pressure in the South as well. “Glass is heavy and of low value. Moving it great distances does not make a great deal of sense,” Ms McKnight said. “It is clear there is not going to be one easy answer, but a variety of answers to the problem.”