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Toilet Tech

Among the thousands of toilets on display at the World Toilet Expo were some that demonstrated clever new ways to use less, or even no, water

4 min read

23 May 2005-It seemed only appropriate that I felt the call as soon as I arrived at the World Toilet Expo.

My bladder pinched. I had to weave through an endless labyrinth of display toilets—none suitable for the immediate need. In brightly lit, multicolored booths, visitors peered into stylish urinals with the Beijing Olympics 2008 logo and bowls that advertised "a powerful, yet frugal flush." Elsewhere, top toilet executives gave speeches with titles like "Creating the Perfect Standard to do Your 'Business' " and "Toilet Culture and Nation Building." The high-ceilinged hall smelled faintly of a flowery deodorizer.

Held 8-10 May in Shanghai, the international expo—which organizers say was the first of its kind—featured the latest models and technology from Japan, the United States, Europe, and China.

The WTO, the World Toilet Organization, that is, decided to hold the event in China in an effort to bridge China's great toilet divide. The standard toilet in China, except in a few big cosmopolitan cities like Shanghai, is still the squat kind, toilet paper not included. Some are mere outhouses, without flushing capabilities. Even in Shanghai only 300 of its 3000 public toilets reach the international standard of construction, cleanliness, and odor (or lack of one), says Xu Jia Min, project manager for the World Expo Group.

After finding some relief at a facility that seemed up to standards, I hunted for the latest in electronically enhanced toilets. I didn't find as many of the funny Japanese models that feature warmed seats and bum-scrubbing capabilities as I had expected. But I did discover the Clean Life II, a Japanese water-recycling system for remote toilets as well as a high-tech, self-cleaning litter box for humans. Both of these inventions addressed China's need to conserve water. With a population of 1.3 billion, the number of flush toilets increasing, and each flush of a toilet requiring 6 liters of water, China is well on its way to becoming the largest toilet-water-consuming society in the world.

The Clean Life II, which is currently used in 100 places in Japan, consists of a computer that regulates set of tanks, pipes, and electromagnetic valves that clean and purify toilet water for reuse. Water becomes clean enough so that even "goldfish can live in the system," says Makoto Kobayashi, president of Ideal Living Designs, the distributor of Clean Life II and a Burlingame, Calif.-based division of Ichinyosha International.

Once a toilet is flushed, the waste collects in a tank and is then transferred to a vaporizing boiler. It's heated to a point that it becomes steam and residual waste. The residual waste, which is cooked until it resembles cigarette ash, is separated from the steam, which is then condensed and returned to the toilet bowl. Three toilets can be hooked up to one Clean Life II system.

The system, which costs US $30,000 per unit, is good for places where it is not "cost-effective to bring in a sewer, where you're out in the boonies," says Mark O'Malley, a sales associate for Ideal Living Designs who came to the Expo with Kobayashi.

Kobayashi said that few Chinese buyers have been interested in the system, probably because it's too expensive. "The Chinese just want to copy our diagrams and reverse-engineer it," he says bluntly.

At a tenth of the cost of Clean Life II, the quirky litter box for humans seems an attractive alternative. Andy Tung, director and general manager of Shinnichi Mechanical and Electrical Equipment, Shenzen, China, calls it "the compost toilet." Waterless and odorless, it consists of a temperature-controlled steel box filled with sawdust. The Korean electronics giant LG designed a microcontroller specifically to run the toilet, according to Tung. Once a user excretes waste, a piece of machinery rotates the sawdust, which is kept at a warm 45 to 50 °C. The moisture evaporates, and the remaining waste and toilet paper then breaks down into organic fertilizer.

The sawdust needs to be changed just once a year. "Essentially, this is what happens in nature. We just speed up the process," Tung says, plunging his hand into sawdust that has been used for six month and holding it to his nose to show there is no odor. He offers to hold it to my nose. I balk at getting any closer than about 15 centimeters, but I don't smell a thing.

The toilet seat can be customized, Tung adds. "I can make a squat or a sit. There's no need for a standard bowl. I have a model that looks like a couch, which is good for old people. You can even put it next to their beds."

The compost toilet, which costs $3000 per unit, has been installed in several government offices in Beijing and the southern city of Shenzhen. Tung says they have been a hit.

A former software engineer, Tung became interested in toilet technology on a visit to Japan a few years ago. It was there that he first used a compost toilet in prefecture of Hokkaido. "I thought, 'This thing really works,' " he recalls.

When a collaboration with the Japanese inventor to bring the toilet to China failed, he took the compost toilet back to the drawing board to see how he could improve on it. He added another screw to give the machinery better rotating power and designed different seats. "I never thought I would be making toilets," Tung says with a laugh. "But I feel like I'm doing something good for the environment. I never knew how much water toilets used."

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