Quiet achiever tech can turn an environmental problem into a profit

The GWE technologies involved use anaerobic digestion to consume organic contaminants in industrial and municipal wastewater streams, removing typically more than 95% of the previously troublesome content by transforming it into biogas (primarily methane). This resource can then be used to fuel industrial processes such as boilers, or to generate electricity, replacing expensive fossil fuels in both cases.

“The quality of wastewater effluent produced by GWE processes from food, beverage and agribusiness processes is often so high that the effluent coming out from plants is often substantially better than the water drawn in from the surrounding environment,” said CST Wastewater Solutions Managing Director, Michael Bambridge.

The technology is applicable to the food and beverage businesses important to both Australia and New Zealand, as well as meat, livestock and crop agribusinesses that must conform with increasingly strict environmental and groundwater statutory obligations.

“A huge bonus also, in addition to the environmental benefits, is that the biogas produced by the anerobic process can then be captured, stored and used to substitute for expensive and polluting fossil fuels, such as bunker oil. So users get both clean water and green energy,” added Bambridge, who is Australasian distributor for the GWE technology, which will be shown at the Ozwater exhibition in Melbourne from May 7th to 9th.

The technology is also available throughout NZ from CST Wastewater Solutions’ NZ Representative, Pieter Groenewegen.

One of the most recent applications of the technology globally involved a central American brewery, Cervecería Centro Americana (CCA), which is adopting GWE technologies to convert wastewater into biogas while achieving effluent quality improvements of 97% in organic matter removal.

CCA’s new wastewater treatment system is designed to remove approximately 97% COD, or Chemical Oxygen Demand, a measure of the organic content in the water. It will produce up to 4,800 Nm³/d of biogas at 76% methane content, which is equivalent to more than 3,200 kg heavy fuel oil/day. This heavy fuel oil is worth approximately $500,000 a year ($A692,000 approx., $NZ729,000 – This assumes a plant running 330 days a year at full capacity and a Heavy Fuel Oil, HFO, price of US 0.46c a litre.)

Like other companies globally adopting the technology, CCA has many choices in order to reuse the biogas. Typical uses that benefit breweries, food processing, and other industries include Combined Heat and Power (CHP) units or other direct combustion systems, such as boilers, turbines, or fuel cells. Where national energy policy permits, companies can opt to generate green energy and sell it back to the grid for a profit.

“Profits from the use of biogas to replace fossil fuels can totally pay for the cost of installing GWE anaerobic digestion,” explained Bambridge. “Total ROI typically occurs in the first five to ten years of operation. Then the plant goes on producing profits from green energy that go straight to a company’s bottom line.

“Other clean green technologies, such as wind and solar power, get more headlines than wastewater-to-energy technologies for their great potential and benefits. But this technology is a quiet achiever that has proven its benefits in Australasia and worldwide and is applicable to a wide range of industries and applications Down Under.”