Wastewater treatment pond may generate power

A $3 million wastewater treatment site which includes  an innovative collection pond design  opened last week  in Waitoa.

The pond features a cover which has been designed to capture methane gas generated by the anaerobic treatment process in the water.

Founder of Wallace Corporation Sir James Wallace said hopefully the company will be able to convert the methane into electricity to power parts of the tanning and rendering plants.

Sir Wallace officially opened the treatment site on December 7 and upon cutting the ribbon to the control room chief executive Graham Shortland said the Corporation will look at using the gases collected over the next 12 months.

“The objectives of the lagoon include improving environmental sustainability and compliance. Hopefully we will be able use the gas to fire up a boiler in the rendering plant,” Mr Shortland said.

The overall cost of the site included the 2mm covering as well as a flare which will be used to burn off the methane gases collected.

Wallace Corporation head of environmental and resource management Aaron Findson said the flare will burn off the methane gas for around six months.

“During this time we will be looking at the quantity and quality of the gas. Then depending on the outcome we will be redirecting the gas down to a boiler in the rendering plant and combine it with fossil gas,” Mr Findson said.

According to ECCA relationship manager Don Lewis the idea of “flaring off” the gas is both an economic and environmental  benefit.

“By burning the gas off into Co², it is 32 percent less harmful to the environment than letting it go into the atmosphere, therefore reducing the carbon emissions,” Mr Lewis said.

The pond  holds 16,000 cubic metres of water.