An innovative new project by University of Melbourne academics will research the agricultural and economic viability of using brown coal to process agricultural waste into fertiliser, reducing greenhouse gas emissions and costs to farmers.
The multiyear project aims to address some of the significant environmental impacts of animal agriculture that occur as a result of reactive nitrogen escaping into the environment as ammonia in animal urine and faeces. This can lead to the emission of highly potent greenhouse gasses, nitrous oxide, or algal blooms in waterways, leading to oxygen-starved 'dead zones' further downstream.
Around half the nitrogen applied as fertiliser on farms is lost to the environment through these and other chemical processes. This is not just a cost to environmental health, but to farmers too: nitrogen fertiliser can account for half the production cost in Australian agricultural systems.
The research led by Professor Deli Chen and published in Scientific Reports in 2015 showed brown coal, known as lignite, decreased the loss of ammonia to the environment by 66 per cent.
It also showed that if the waste were collected and processed into fertiliser, it would be worth around $49 per cow per year – an enormous boon for many agricultural operations.
Professor Chen and a multidisciplinary team of soil scientists, chemical engineers, agricultural scientists and economists are now preparing to test the reuse model in the new $7 million Cooperative Research Centres Project (CRC-P), "Optimising nitrogen recovery from livestock waste for multiple production and environmental benefits."
CRC-P grants fund short-term industry-led collaborations to develop important new technologies, products and services that deliver tangible outcomes.
This CRC-P project is funded by the University of Melbourne, the Australian Department of Industry, Innovation and Science and industry partners including Australia's largest milk producer, Australian Fresh Milk Holdings.
Professor Chen said that the project will demonstrate and evaluate the new technologies at commercial scale.
"More than half of the world's population is nourished by food produced using synthetic nitrogen fertilisers, which are manufactured in energy-expensive processes that account for five per cent of the world's total natural gas production, or two per cent of the world's total annual energy supply.
"The loss of reactive nitrogen to the environment is therefore an enormous burden on the environment and human health, and an enormous economic burden to farmers worldwide."
Co-funder Australian Fresh Milk Holdings will host a dairy pilot facility including lignite traps for waste, composting facilities and other infrastructure, and co-funder Ming Mornington will explore the use of lignite in a poultry facility.
National industry bodies Meat and Livestock Australia and Dairy Australia will provide support for research activities, training and opportunities and strategies to develop and assess the technology.
The three-year project will demonstrate methods that lead to reduced environmental impact and improved resource recycling that better align with consumer expectations and values as well as demonstrating the commercial benefits of better waste management.
