Pig poo problem solved

An Australian-led project to turn 1.4 million tonnes of Chinese pig poo into alternative energy and fertiliser has been hailed in a national science award.

The project, run by the Adelaide-based Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Chinese firm HLM Asia and Huazhong University of Science and Technology, has developed technology for treating one of the world’s largest and smelliest waste disposal problems.

CRC CARE was presented with a federal government 2013 CRC Star Award by the Head of Division, AusIndustry, Chris Butler, during the CRC Association Conference’s Excellence in Innovation Awards dinner on 16 May. The awards recognise CRCs for working with small and medium enterprises (SMEs) to drive innovation.

“China has 1.8 million pig farms and over 700 million pigs, while pork makes up 67% of the nation’s meat consumption,” said CRC CARE Managing Director Professor Ravi Naidu.

“It is estimated that the Chinese pig industry generates 1.4 million tonnes of pig excreta and 7 million tonnes of urine per year. However, only 10% of this waste is currently treated, posing a considerable disposal headache as well as health and water quality risks.”

The project has developed a two-step anaerobic biodigester for treating pig waste in bulk and established the settings for load and digestion time. It has also determined that a special combination of different anaerobic treatments is effective for this type of high-nutrient waste and that it can produce clean biogas energy.

The technology has been trademarked as pooCARE. It has been demonstrated in the field and is now being scaled up to treat large volumes of waste from many piggeries.

Professor Naidu says that the demonstration biodigester can:

• remediate 200 tonnes of piggery waste daily (73,000 tonnes annually);
• produce 380 m³ of biogas daily, worth around AU$41,000 a year as a heating fuel;
• produce 5600 tonnes of fertiliser worth AU$550,000 per year.

“CRC CARE has also been working with the pork industry in Australia, including the Pork CRC, to transfer the biodigester technology from China to farms in Australia. This will enable Australian piggeries to gain a new income stream from their waste, which will help support farm operations, grow algae and produce biochar to provide soil nutrients, and increase the sequestration of carbon in soil.

“Our technology doesn’t just solve a big and rather smelly problem for China - it does so for the world. Pork consumption is rising globally due to the increased demand for meat, and this development, which recycles the energy and nutrients in pig waste, makes a major contribution to the sustainability of this industry,” Professor Naidu added.

The project involved collaborations with a number of Australian and Chinese SMEs and its technology is likely to be taken up internationally in countries such as India, as well as in Australia and China. With further development, the technology has global potential for many types of farm animal waste.

The Minister for Science and Research, Senator Don Farrell, said CRC CARE richly deserved the award for its key role in engaging industry and researchers with SMEs to drive and deliver innovation.