Tuesday January 5, 2010
New use for food scraps
Stories by TAN CHENG LI
Almost half of our discards can be recycled to make our gardens flourish.
LOOK into your trash bin. What have you got in there? If you have been recycling religiously, sending all your paper, plastics, metals and glass to the recycling centre, all that’s left in the bin would be kitchen scraps. Why not go a bit further with your green efforts and recycle even that as well?
Almost half of our discards has no place in the trash bin, being organic waste which can be recycled through composting, to become food for the soil. Given that Malaysian households generate over 17,000 tonnes of refuse a year, a figure that is projected to rise to 30,000 tonnes within the next decade, we can significantly cut down on what goes into our trash cans and ultimately, into landfills, through composting.
The Solid Waste Management and Public Cleansing Corporation has that in mind, and so plans to include composting in the effort to shrink waste heaps. It is encouraging households to recycle their organic waste using the Takakura composting method, a cheap and effective way to compost waste that can easily be done at home.
Last month, it held a workshop to train a staff of 80, including those from local governments, on the composting technique, with support from Japan’s Institute for Global Environmental Strategies and Japan International Co-operation Agency (JICA).
Koji Takakura, the environmental engineer who had devised the composting technique, was at hand to teach the method.
Corporation chief executive officer Datuk Zaini Md Nor says the trained personnel would later impart the technique to other groups such as resident associations, women’s groups and environmental non-profits.
“About 45% of our waste is organic material. If we don’t recycle this waste, it is just discarded. Through composting, we not only can get compost, but can reduce almost half of our waste, instead of sending it to the landfill,” says Zaini.
When organic food ends up in landfills, it breaks down ever so slowly and releases polluting leachate and the greenhouse gas, methane.
He says while waste concessionaires such as Alam Flora and Southern Waste Management could do large-volume composting, the agency is concentrating on household composting first as this approach reduces waste at source. “If households are already composting, it will not be necessary for Alam Flora to have two bins for separation of organic and recyclable wastes.”
The traditional way of composting is a lengthy process with the pile of garden and kitchen refuse piled up to slowly degrade over months. Now, there are newer methods which speed up the process through the use of inoculents rich in waste-chomping micro-organisms.
Takakura, deputy director of Wakamatsu Environment Research Institute in Kitakyushu, Japan, introduced his composting method in 2003. “With this method, families can practise composting safely and easily in their homes. It will reduce decomposing food and foul odours, and so, improve hygiene. Composting will also avoid emissions of methane gas and change waste into a resource that can be used in gardens and farms,” he says through an interpreter.
The Takakura home composting method is simple, requiring only a perforated container, and works fast. Food scraps break down within a day or two, and crumbly, earthy compost forms in weeks instead of months like in other methods.
The decomposition is sped up through the use of a seed compost rich in micro-organisms, pretty much like in other composting methods that use inoculents or activators such as bokashi, enzymes or Effective Micro-organisms.
The Takakura method has one advantage though: it requires no purchase of such additives as the seed compost is home-made, with the micro-organisms in it cultured from local materials such as fermented foods (tapai, tempe, yoghurt, miso paste or tau cheong), fruit peels, vegetable scraps, jaggery, rice bran and rice husks.
“Organic waste easily putrefies unless it is treated properly. One way to do this is by applying a large quantity of fermentative micro-organisms which will lead to a desired fermentation process. During the fermentation process, the temperature of the compost heap can exceed 60°C, thus killing bacteria, parasites, insect eggs, weeds and other organisms, making the compost hygienic and safe,” says Takakura.
His method is also suitable for composting large volumes of waste commercially.
For this, Takakura says a covered shed is needed, together with a mechanised shredder to chop up the waste to speed up the fermentation process.
His method, he adds, is cheaper to operate than other composting methods and yet, gives higher yields.
The Takakura method was first effectively used in Surabaya, Indonesia, and is slowly spreading throughout the region.
In Perak, Kampar council officials, after trying out the Takakura method in September and finding it superior to other composting methods, plan to distribute composting baskets to 200 households in Taman Batu Putih for a pilot project.
Toshizo Maeda, a consultant with Japan’s Institute for Global Environmental Strategies, says in Sibu, Sarawak, small-scale composting projects in some schools and homes since 2006 have cut waste heaps by 3%.
The Sibu Municipal Council intends to expand the effort with Takakura composting. In March, it will distribute seed compost and composting baskets to about 150 households and treat waste from markets at its composting centre.
The centre, set up in late 2007, now processes waste from some restaurants and markets using conventional composting.
Though it would be possible for a waste company to set up a composting centre next to a landfill, Maeda says it is preferable to have one near a market as the waste would be unmixed with other inorganics.
“Communities can also set up their own composting centre. The city council can support them by making a commitment to purchase the compost,” he says.
To encourage home-composting, he says local governments should distribute seed compost, together with composting baskets, to households and even establish community composting centres.
Government figures show that only 11 of the 155 waste disposal sites in Malaysia are engineered sanitary landfills with anti-pollution measures. Of the remainder, 71 have only controlled-dumping measures, while 73 are just open dumps. Add to those the countless illegal dumps peppering countrysides, and we are saddled with many potential polluted sites. The land contamination, however, can be partly resolved through composting. Not only that, by recycling our kitchen and garden refuse into compost, we’re returning the nutrients and energy from these stuff back to the soil.