Converting food waste is not a rubbish idea

Updated: 2012-01-30 07:55

By Diao Ying (China Daily)

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 Converting food waste is not a rubbish idea

Is there anything useful in all this garbage? A scavenger, working through a Beijing landfill earlier this month, is one of many who live on the waste they can recycle. Wang Jiuliang / for China Daily

 Converting food waste is not a rubbish idea

Above: Sanitary workers put kitchen waste into a special garbage tank in a residential community in Beijing. Residents are encouraged to sort out their rubbish for recycling. Below: Goldenway Bio-Tech's food waste treatment factory at Gao'antun, Beijing. Wang Jing / China Daily

 Converting food waste is not a rubbish idea

Provided to China Daily

Converting food waste is not a rubbish idea

Leftovers can be easily transformed into fertilizer, animal feed and energy, Diao Ying reports in Beijing.

Sheep wander amid mountains of rubbish as collectors dump garbage from carts. Pigs swarm as people put cooking waste in front of them. Dogs yelp when outsiders approach stoves where used cooking oil simmers.

Those are scenes in Besieged by Waste, a documentary made by artist Wang Jiuliang, who spent two years shooting landfills surrounding Beijing. As the city expands so does its volume of waste. Beijing's 20 million residents generate 11,000 tons of cooking waste every day.

Not all of it ends up in landfills. Some becomes feed for livestock. Some is processed and used again in restaurants. With food safety dominating headlines, government agencies vowed to check sources of cooking oil and work on quality standards.

Meanwhile, entrepreneurs see opportunity in the table scraps and orange rinds, bones and congealed oil you see - and smell - late at night along Guijie, the city's most popular street for gourmets.

"The treatment of food waste is a flourishing industry," said Ren Lianhai, a scholar with Beijing Technology and Business University.

Some companies are working on technologies to generate electricity with rubbish. Others plan to turn food scraps into fertilizer or animal feed.

In Gao'antun, northeast of Beijing, barrels of food waste are delivered to treatment facilities. The waste is fed into a machine with an enzyme, is heated to 75-80 degrees Celsius for 10 hours, and emerges as a brownish powder that can be used in soil as fertilizer. A few bones and toothpicks might remain, but the gutter smell is gone.

Beijing Goldenway Bio-Tech operates about 10 such facilities as it tries to tap into the field of rubbish treatment. When put into full operation, the company says, this one factory could deal with 400 tons of waste a day.

The company sees those millions of bits of food as raw material for organic fertilizers. "They are actually raw materials of abundant supply and extremely low cost," said Yu Jiayi, Goldenway's CEO.

The company was founded eight years ago, before food safety and rubbish treatment grew into the issues they are today, but Yu saw the potential. She had studied animal nutrition in China, had headed State-owned agriculture companies, and then had studied international commerce and globalization in the United Kingdom.

Natural balance

Yu, 49, sees the world as a constant recycling of chemical elements. Nature works through the interaction of animals, plants and microbes, she said. Ideally, the three work consistently and reach a natural balance. But the natural process has been disrupted in China by the expanding gap between urban and rural areas, she said.

Consumption by urban dwellers increases rapidly as cities expand. Trash treatment facilities can't keep pace, so rubbish is transferred to outlying areas. As a result, huge cities are surrounded by rubbish landfills, as Wang's documentary shows.

But it's not just a useless mess. Yu said about 70 percent of China's urban trash is rich in organic compounds. The challenge is to distill the nutritious elements from them and put them to use.

The abundance of rich garbage material in urban areas contrasts with the poor soil in some rural areas, where peasants turn to chemical fertilizers to boost agricultural production. Such fertilizers can increase output in the short term; in the long term, they damage the soil and make it more barren.

Further, too much of certain elements in those synthetic fertilizers, such as nitrogen, enters the water supplies and becomes a source of pollution in the ecosystem. Some chemicals also can go into the vegetables and fruits, making them decay easily and harming people's health.

For Yu, the solution is to reconnect the ecological chain. The company collects the garbage in urban areas, processes it, makes it into organic fertilizers and sells them to the rural areas.

Business value

In addition to the goodwill factor, Yu's business plan has the potential of producing profits. China generates about 1 billion tons of rubbish a year, 10 million tons of it cooking waste. The most common ways of disposal are to burn it or bury it. Neither way creates any business value.

Many rubbish treatment companies depend on government subsidies as their main source of income. Goldenway says it can ask for fewer subsidies because it can realize income through the sale of its fertilizers.

And the company obtains the raw materials almost for free, providing a competitive edge. Goldenway sells fertilizer through big State-owned companies, such as Sinochem Group, and directly to the government, which distributes it to rural areas.

Unlike most fertilizers used in China, Goldenway's fertilizer is organic, which can make the soil healthier. Zhang Hailiang works a strawberry field on a farm in Changping, northwest of Beijing. When he started, he said, the soil was almost barren. "It was so hard that our tools broke when we tried to turn the area into a strawberry field."

After three years, the soil has recovered its quality and now produces strawberries. "The farmers all know that the organic fertilizer is useful," Zhang said. "Some even fight for it."

Investors interested

Goldenway has just started to turn a profit, and financiers have seen its potential. The company received 167 million yuan ($26.4 million) from investors including Goldman Sachs in 2007. Tsing Capital, a venture capital firm that specializes in clean technology, invested $11.7 million two years later. Goldenway is preparing to seek a stock market listing next year.

Yu sees her company as doing well by doing good: By turning food waste into fertilizers, it will also cut the supply of oil processed from cooking waste.

Some people collect the waste, distill oil from it, and sell the oil to restaurants - hence, it is called waste oil. It also is called gutter oil, digouyou, because sometimes restaurants discard their used oil into the streets and sewers, and that oil too is reclaimed and sold. Its use in cooking is illegal, and a serious health risk.

Goldenway processed the cooking waste for the Olympic Village during the 2008 Beijing Olympics. It now has around 10 treatment factories in Beijing; others are being built. The company expects to expand the network to other cities in China as the government promotes the policy of rubbish classification.

Mo Jianguo, who runs a website for the cooking waste treatment industry, said more companies have entered the field but very few of them are profitable. Some are looking for quick money, he said, because clean energy and the environment are popular spheres for venture capitalists and private equity investors.

2 big challenges

Mo said treatment companies face at least two problems. First, the government's policy on cooking waste is still not clear. "Restaurants can make money by selling their waste to illegal collectors, and they are not willing to give it out for free," he said. Each year, about 2 million to 3 million tons of gutter oil is reused.

This might be improving. In 2010, the State Council released a general guideline on the management of waste cooking oil, urging local governments to pay closer attention to the recycling of it. The Ministry of Public Security said in December that 700 people had been arrested on charges of collecting and manufacturing gutter oil since August. Other government agencies say they are working on standards to test the quality of cooking oil.

Sorting out waste is another problem. The classification of rubbish, a common practice in developed countries, is far from widespread in China. The government started experimenting in some key cities in 2000. In Beijing, for instance, some neighborhoods have barrels colored and labeled green for kitchen waste, blue for recyclables and black for other waste. But many households still put all their waste in the same plastic bag and throw it away.

"I know someone who said they just don't have enough space for so many barrels," Mo said. He said some companies try to generate electricity by burning waste, but when everything is mixed together, they sometimes cannot manage to burn.

Goldenway now collects mainly from companies assigned by the government. It hasn't yet tapped into individual families, a main source of cooking waste.

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