A major new methane gas collection project has been launched at Nippon Meat Packers’ Oakey abattoir in Queensland – promising to slash the plant’s annual gas energy bill by close to half, as well as greatly reducing its carbon footprint.
The project will focus on the use of a latest-generation COHRAL (Covered, High-Rate Anaerobic Lagoon) technology, which will extract green energy biogas from the plant’s waste-water streams to replace large quantities of natural gas currently bought by the abattoir.
Significantly, the project is entirely self-funded, and did not attract support under the former Federal Government’s carbon abatement grants.
A string of Australian abattoirs, renderers and associated businesses last year received funding support for carbon mitigation work. Easily the largest of these was a $23 million grant to Bindaree Beef, for a process that is unproven in the global processing industry. Bindaree falls within in the electorate of the former independent local member, Tony Windsor.
A sod-turning ceremony marking the start of the Oakey project took place near the Darling Downs plant on Friday, led by Federal industry minister, Ian Macfarlane. The project should be up and running by late 2015.
Oakey general manager Pat Gleeson said the occasion reflected Oakey’s commitment to the environment, its customers, employees, neighbours and the broader community in ensuring that the plant remains a strong and sustainable manufacturer for years to come.
The overall project cost is expected to be about $5 million, but is expected to deliver a return on investment within four years, Mr Gleeson said.
The change of government meant Oakey missed out on Federal funding support for the project last year, and the new Coalition Federal Government is now in the process of rescinding the controversial Carbon Tax.
“But despite that, we felt it was too a good a project not to go ahead with,” Mr Gleeson told Beef Central.
“Nippon Meat Packers has always been a highly innovative company. It adopted the Marel traceability/accountability system in the Oakey boning room years ago, which has proven to be a magnificent investment, despite its detractors at the time,” he said.
Mr Gleeson said like all processors, Oakey had to assiduously look at its processing costs and its impact on the environment, and for both reasons, the latest waste treatment project made very good business sense. The investment was reflective of the broader decisions being made worldwide by parent company, Nippon Ham.
“Looking at it simply from the bottom-line impact, natural gas costs are only going one way. Energy is a very significant, and rising component of our operating costs,” he said.
The project is designed to collect around 6000 cubic metres of methane each day, calculated to produce a saving of about 50,000 gigajoules of bought natural gas pumped through Oakey’s boilers each year. Put another way, the methane produced from the installation has the potential to generate around a megawatt of electricity each day.
The project has potential to reduce the company’s overall annual gas bill by 42 percent. Gas, together with electricity and diesel, are significant sources of energy for the Oakey plant.
The installation is also about making Oakey better-equipped to handle any future expansion. There is a vision that the plant might grow to 1500 head-per-day throughput, using a six-day operation within three years, once national herd-recovery starts to gather pace after the drought ends.
While the justification for the project has been driven very much by the energy cost saving, there is also a huge upside from an environmental management perspective, in presenting the company’s environmental credentials through beef brand messaging and associated work.
Asked whether the Oakey project might be a precursor to similar work at other NMPA plans like Borthwicks (Mackay) and Wingham (NSW), Mr Gleeson said the performance of the project would obviously be closely monitored.
“If it ticks all the boxes, I can’t see why it would not be duplicated right across the group,” he said.
Odour emissions are also expected to be reduced, and another environmental spinoff will be reduced sludge disposal issues. It will also deliver better quality water for use in crop irrigation adjacent to the Oakey plant.
Technology new to Australian ag sector
The technology to be adopted at Oakey is regarded as a considerable advance on earlier covered pond biogas systems. It has not been seen previously in Australian agriculture, but is well proven overseas.
Michael Bambridge is the director of CST Wastewater Solutions which is designing and installing the facility. One of CST’s specialities is in the area of anaerobic pre-treatment of food and agricultural waste water and recycling for energy use.
“This will be the best engineered waste water treatment process in any abattoir in Australia,” Mr Bambridge said. “It will make Oakey a showpiece plant in wastewater treatment and biogas collection, by any standards.”
One of the features will be that it will adapt a process normally used in industrial applications, relying on tank storage, for use in an earth lagoon system.
The project will be the first in the world to utilise the COHRAL system in a covered lagoon application. The 300 existing COHRAL installations worldwide all rely on the use of reactor tanks, either cement or steel.
A novel distribution system along the bottom of the lagoon will allow the process to reduce the water retention period from about 25 days back to 15 days. A unique settling system after the lagoon will also be used.
“With anaerobic treatment, it’s all about concentration of the methane forming bacteria and mixing with the waste-water,” Mr Bambridge said.
“We don’t believe in having gas storage underneath flexible pond covers,” he said.
“The covers go up and down, creating weakness, and eventually they will start sucking air. Air and methane is an explosive mix. Instead, the Oakey project will rely on a floating membrane kept at slightly negative pressure, meaning it not inflate, with the gas drawn off as soon as it is produced.”
Compared to ‘inflated’ single membrane pond covers, the risk of leaks was virtually zero.
The collected gas will be held in a specially-designed twin-layer ‘bladder’ storage, sufficient in size to store gas generated over weekends and non-kill days.
Before use, the methane is simply cooled and any moisture and hydrogen sulphide removed, to avoid corrosion issues, before being pumped in to fire the boilers.
The technology was well proven in Europe, where such installations had been made for a decade or more, Mr Bambridge said.
One of the important aspects once the new system is operational would be to closely manage ‘what goes down the drain.’
“The factory itself will have to improve its waste management practices in order for the biogas project to perform at its optimum level. People will no longer be able to just throw anything down the drain. It takes some management to get the best performance from the bacterial action,” he said.
Pat Gleeson said the system’s performance could be affected by something as simple as washing the wrong chemical cleaning agent down the drain.
“It will require a new level of diligence among staff, to make sure we do not compromise the bacterial action that’s going on. But we suspect staff themselves will be keen to see the system work to its best capacity,” he said.
Adoption of the technology was the result of an exhaustive research and selection process. Much of the background research undertaken for the project was carried out by Oakey's engineer, Justin Caldwell.
Anaerobic digestion facilities have been recognised by the United Nations Development program as one of the most useful decentralised sources of energy supply, as they are less capital-intensive than large power plants. They can also benefit local communities by providing local energy supplies and eliminate the need for large and often smelly and environmentally- challenging settling lagoons.