Composting on a commercial scale - the way forward for our councils?

Credit: CORE

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Composting - it's dirty business, but an important one. Families with backyard bins and wiggly worm farms have long been helping divert greenhouse-gas-leaching waste from landfill, and getting soil-boosting juices and mulch for their gardens in return. Now it's councils and businesses that are hearing the call to compost, with keen campaigners pushing for kerbside collection services and more.

Around 60 per cent of our rubbish is compostable, but for those without the time, space or inclination to start a compost heap in the yard, it all ends up at council waste facilities, most likely in landfill to be buried anaerobically along with other mixed waste.

Alarmingly, such a huge amount of organically active material in landfill is responsible for over 3 per cent of Australia's total greenhouse gas emissions annually, producing methane, a gas with 25 times the global warming potential of carbon dioxide.

According to Compost Australia - a division of the Waste Management Association Australia and the peak body representing the Recycled Organics Industry - if properly composted instead, this same organic waste could help to abate climate change and improve soil quality by sinking carbon back into the soil. Using compost on land could also reduce the need for water by an average of 30 per cent.

In the lead up to International Composting Awareness Week (2-8 May 2010), now in its fifth year and hosted by the Centre for Organic & Resource Enterprises (CORE), the group will be lobbying councils around the country to get on board and work with householders and businesses to progress composting.

"The Government will be placing a carbon levy on landfill, which in turn will pass on a higher cost to communities," said CORE Chairman, Eric Love. "This is a great stimulus for keeping organics out of landfill, but out of the 700 or so councils in Australia, only a fraction of them are offering a third bin for organics."

Even some of the multinationals are making the move to compostable packaging. At its 35 stores in South Australia, fast food chain KFC is introducing biodegradable bags developed by Melbourne company Cardia Bioplastics. KFC's move to biodegradable bags follows the SA Government's ban on plastic bags nine months ago. A similar ban is expected to be enforced in Western Australia from next month and the Northern territory is looking at similar options.

Cardia's Managing Director, Frank Glatz, said the bags meet international durability standards and after being used, "can be composted and will break down within six months, in line with international biodegradability requirements." But he acknowledges that the bags are only as "green" as the waste management processes used at the end of their life.

"If food, biodegradable bags and other organic matter are disposed of along with cans and bottles, it's not useful. It needs to be collected and processed as a clean stream," he said.

So far, councils are in the early stages of implementing composting sytems. Soon to come online with a kerbside collection model for organic material is Brisbane Council, covering a massive 300,000 households. This will make a significant difference in the percentage of waste that is composted, said Love, adding that while the collection and even the process of composting are straightforward, the real challenge is "finding markets for applications and synchronising them at the same rate as they are diverted from landfill."

"That's the main obstacle to introducing composting nationwide," he pointed out. "All the quality standards have been achieved and now only marketing the opportunities to businesses remains."

Compost has a myriad of commercial uses. There are about 140 businesses in Australia recovering more than 5.2 million tonnes of organic wastes and turning them into useful products and services each year. Most of this organic material is turned into compost products at commercial scale composting facilities with capacities of between 10,000 and 100,000 tonnes per annum. The remaining recycled organic material is either applied directly to land or used to generate heat or electrical energy.

Composted materials can be used for top dressing and mulches for parks, gardens and golf courses. Tailored products are available for agricultural applications such as fruit and vegetables, grains and cereals, pasture improvement and forestry. Compost products can also regenerate mining- or salinity-affected areas and can be used to help clean storm water before it travels into the ocean.

The Recycled Organics Industry is also developing new uses for compost, from liquid compost extracts (known as 'compost tea') that suppress disease in grape vines to compost erosion control 'blankets' that prevent erosion in road cuttings.

For more information about composting check out www.compostweek.com.au and www.compostaustralia.com.