Getting in sink with waste disposal units
The move towards recycling stuff from sewage into valuable biogas could also give an older technology a new lease of life.
Composting has always been the most eco-friendly and efficient option for dealing with food waste wherever possible. Most people in New Zealand have access to even a small garden to do this, or to bury the pickled results of the small ‘Bokashi’ buckets.
But, for those few who don’t, and for workplaces where nobody takes this on, in-sink waste disposal systems offer another clean and easy option. These machines, which have been around since 1927, shred any food waste you put down the sink, removing 85 percent of the solids so the rest can be washed away.
The concern with their use has been whether the sewage systems can deal effectively with this food waste once it reaches the works. Until recently, this was simply removed with other solid waste and trucked to a landfill. This risked making a waste disposal unit more costly and environmentally damaging than composting, or even just sticking your food waste in a normal bin.
But updated municipal sewage systems can now handle the load and those with biogas digesters create the potential to turn all this waste into valuable commodities.
Andy Higgs from Parex, the New Zealand distributors of the InSinkErator brand of waste disposal units, is understandably enthusiastic.
“It wasn’t originally designed as an environmental piece of equipment,” he says. “But it is a technology whose time has come.”