Rotorua to gain from innovative research

Rotorua to gain from innovative research

Today the Minister for the Environment Hon Nick Smith announced that an innovative Rotorua research initiative will be awarded $1 million over two years from the Ministry’s Waste Minimisation Fund, subject to signing of the deed.

The research project involves Crown Research Institute Scion and Rotorua District Council who joined forces in 2008 to develop a new approach to the management of organic waste.

Aptly named “Waste 2 Gold”, the project uses new technology developed by Scion to turn biosolid waste produced from Rotorua’s municipal wastewater treatment plant into valuable by-products, such as chemicals, fertilisers or energy.

Scion’s Chief Executive Tom Richardson says this level of investment recognises the potential of the technology to return significant economic and environmental benefits not only locally but throughout New Zealand.

“This is very exciting news for Scion and our partner – the Rotorua District Council. This project enables us to take science out of the laboratory into a pilot plant where we can test the technology at a scalable level”, he says.

The new ‘STOP’ (Scion Thermal Oxidation Process) technology stemmed from a process being researched for the pulp and paper industry. It has the potential to reduce biosolid volumes 30-fold and also substantially reduce greenhouse gas emissions and leachates that arise from organic waste.

The pilot plant will use a thermal deconstruction process that “cooks” the biosolids (sewage sludge) and breaks them down into re-useable nutrients and a range of other added-value chemicals. In addition, methane can be produced for electricity production.

“We see the potential of Waste 2 Gold to not only solve our waste disposal problem but to provide a revenue source from the converted waste. Rotorua has approximately 8,500 tonnes of biosolid waste going to landfill every year at a cost of $900,000. This project has the potential to further reduce all organic waste going to landfill,” says Rotorua District Council Chief Executive Peter Guerin.

Rotorua is a good model for many cities in New Zealand, with the same challenges regarding the disposal of biosolids and other municipal wastes. The technology can be implemented in other urban centres, and for applications beyond sewage sludge.

Scion says that research shows that the same technology could also be used for managing organic wastes from food and industrial processors.

“The waste streams from pulp and paper, agriculture, dairy, meat and fruit processing represent a tremendous added-value resource for New Zealand that can be tapped into by environmental technologies like STOP”, says Dr Richardson.

The pilot plant, to be constructed on the Council’s waste water treatment plant site, will be operational by January 2011.

The new funding will contribute to a two-year research programme that will thoroughly trial the process and make sure it can work on a full commercial scale.

If successful, a full-scale plant in Rotorua could initially remove up to 8,500 tonnes of biosolid waste going to landfill per year, and ultimately achieve net benefits (in terms of cost reduction and value creation) of around $4 million per year for the council and community.

About the Waste 2 Gold project

Scion’s Waste 2 Gold platform provides a sustainable solution to the disposal of solid organic wastes. It is based on a deconstruction process that uses heat, pressure and air to convert organic wastes. The results could benefit the council, the community and the environment. For example:

• Acetic acid production: commercial ethanol is currently used to improve the sewage treatment system's ability to remove nitrogen. The acetic acid produced through Scion’s process could replace this ethanol, with potential savings of $367,000 per year.

• Energy generation: the process is essentially a "wet combustion" and will generate excess heat for use in the deconstruction plant and elsewhere at the site. In addition, methane will be generated at several stages in the system for electricity production.

• Environmental improvements: significant greenhouse gas reductions (>70%) will be achieved through deconstruction. In addition, high nutrient content leachates will no longer enter lake-bound waterways around the landfill.

• The deconstruction stage leads to a 30-fold decrease in biosolids volumes - meaning a potential saving of $900,000 per year in transportation, landfill fees and waste levies.

Scion’s approach differs from others in this field in that it controls the deconstruction process to yield useful chemicals for downstream bioconversion, rather than complete breakdown to CO2 and water. Likely implementers of the technology include local councils and waste management companies.

Other possible customers for the technology include (1) industrial organic waste producers (e.g. primary industries), who are looking for reduced disposal costs and alternative use options; and (2) chemical companies that may want to generate and recover chemical intermediates from the waste stream as replacements for fossil fuel-derived equivalents.

Scion has filed an international patent for the STOP (Scion Thermal Oxidation Process) technology.

ENDS

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