国产热热热精品,亚洲视频久久】日韩,三级婷婷在线久久,99人妻精品视频,精品九热人人肉肉在线,AV东京热一区二区,91po在线视频观看,久久激情宗合,青青草黄色手机视频

Business / Industries

From human waste to 'black gold'

(Agencies) Updated: 2015-03-09 07:54

A growing number of Chinese farmers are making full use of fecal sludge at home by turning it into fertilizer and biogas

From human waste to 'black gold'

A farmer in Zouping county, Shandong province, use fertilisers made from human and poultry waste in her farm to boost vegetable growth.[DONG NAIDE / FOR CHINA DAILY]

Heinz-Peter Mang is obsessed with turning human waste into gold. As millions of Chinese move to cities, the German engineer is convinced the country is on the way to hitting the jackpot.

A growing portion of China's toilet waste is converted into fertilizer and biogas. In Beijing, 6,800 tons of human excrement are treated each day by some estimates: enough to fill almost three Olympic-size swimming pools.

Over the past decade, China's economic ascent has driven millions of rural workers into its cities in the largest migration in human history. In 2013, the number of urban dwellers crossed 731 million, overtaking the rural population by more than 100 million. Some fallouts: water shortages in the North and toilet waste routed into rivers in the south.

That's forcing city planners to get creative in dealing with toilet refuse, and drawing engineers like Mangto help refine models. The push to re-purpose feces into energy resources or fertilizer is expanding across China, and Mang is advocating for the model to be copied in other parts of the world.

"The world has much to learn from China in the way it's harnessed waste for energy," said Mang, 57, who now works with graduate students on ecological sanitation projects at the University of Science and Technology Beijing. "With the lack of taboo around reusing fecal matter, it's all about the science for safe reuse, and with more and more people moving into cities there's an unprecedented opportunity."

Sludge recycling

Globally, a variety of techniques are used to handle human waste: some cities dump it in rivers, others choose to incinerate, and still others bury it in ditches. United Utilities Group Plc, Britain's largest publicly traded water company, handles the sewage of 1.2 million people in Manchester and operates a sludge recycling center that runs on enough human waste to power 25,000 homes.

While other parts of the world also harness fecal sludge into resources, and human beings have for centuries found ways to re-purpose their waste, China's opportunity to do so is unmatched as the nation's cities become more crammed.

Loop closing

Mang's life and work has centered around China, and offers a window into the country's evolution on managing waste. He first arrived in Chengdu, China, in 1982 as part of a German government delegation, collaborating with China on a biogas project.

He was hooked from the start. The willingness of the Chinese to try different ways to use waste sustainably was amazing to Mang, then a newly graduated environmental engineer who authored a master's thesis on sustainable uses of sewage sludge.

Previous Page 1 2 3 Next Page

Hot Topics

Editor's Picks
...
遂溪县| 阿克| 黔西| 叶城县| 大荔县| 万源市| 丰顺县| 全南县| 建平县| 香港| 长治县| 阳城县| 碌曲县| 宜州市| 安乡县| 舟山市| 肥乡县| 沐川县| 营口市| 沙湾县| 泉州市| 阿拉尔市| 万盛区| 长岭县| 江津市| 杭锦后旗| 剑川县| 泰顺县| 望谟县| 正定县| 凌云县| 晋城| 大冶市| 青铜峡市| 郓城县| 秦安县| 建平县| 重庆市| 鄂托克旗| 常宁市| 民乐县|