No. 111: Building an environment-conscious sewage system in disaster-stricken districts (November 9, 2011)

The efforts to build an environment-conscious sewage system in collaboration with the local governments hit by the Great East Japan Earthquake are growing widespread. Sekisui Chemical will collaborate with Sendai city to build a system that creates hot water using the exhaust heat from the sewage pipe that is around 20 degrees centigrade all the year round. Using Sekisui’s technology on the production of resin sewage pipes, the system will take out heat using the resin sheets on the bottom of the pipes. It is possible to install the system without breaking the existing sewage pipes. Metawater and Kesennuma city will together build a system to utilize a large amount of fishery wastes from seafood processing plants. The system mixes the wastes with sewage sludge and generates electricity using heat and methane gas generated in the fermentation process. The generated power will be used in the plant.

The Ministry of Land, Infrastructure, Transport and Tourism has positioned these two projects as government-supported research projects. The two local governments and private companies involved will build equipment for substantiative experiments. After examining the results of these experiments, the government is scheduled to expand these efforts to other local governments. About 40% of the 150 sewage treatment plants were destroyed in the Fukushima disaster, and the damages are estimated to be several hundred billion yen.

In addition to these local governments and private companies, Japan IBM is studying the construction of an eco town with Sendai city, and Boston Consulting Group is working on building a seafood processing plant on the seacoast that uses renewable energy in collaboration with Iwate Prefecture. Hitachi submitted a proposal on an environment-conscious town to more than 10 local governments, while Fujitsu made the same kind of proposal to a prefecture on the coast of the Sea of Japan.  

No. 110: Using a sewage plant as the base of resources recycling (November 7, 2011)

Subsidized by Ministry of Education, Culture, Sports, Science and Technology, Toyohashi University of Technology will start a substantiative experiment of a system that uses a sewage plant as the base of resources recycling for effective utilization of biomass and carbon dioxide with an investment of 600 million yen in 2014. In the experiment, the research team will produce biogas and fertilizer from sewage sludge and waste. The generated biogas will be used for power generation, and the generated carbon dioxide will be used as an agent to facilitate the photosynthesis of farm products and seaweeds.

The generated power will be used to run the equipment, the generated heat in power generation to dry sewage sludge, and the generated carbon dioxide to operate the cultivation facilities inside the plant. Facilitating the photosynthesis is expected to increase the yield by 30%. Biomass will be solidified and distributed to local farmers as fertilizer. In the experiment, the research team will study how much the system will be effective to reduce carbon dioxide emissions and the economic potential of the system. The local gas company will provide the elementary technology for the production of biogas and fertilizer and the facilitation of the photosynthesis. Besides such nationwide companies as Sinfonia, local companies including TBRCorp. and Ishiguro Group will participate in the experiment. The preparation for the experiment will start in Toyokawa Water Purification Center late this year. 

No. 109: Water business in Japan and the world (28) (November 1, 2011)

Building a society that does not waste water

Water is a finite resource. In order to prepare for the decreased safety of water utilization caused by climate change, we need to build a society that does not waste water. Climate change causes not only a drought but also a flood as we see in the ongoing disaster in Thailand. If we set water in water reservoir and underground water apart for later use by virtue of effective utilization of rainwater and reclaimed water, we can secure stable water supply even in a drought. Tokyo uses 426 cubic meters every day that is equivalent to 3.4 times bigger than the volume of a Tokyo Dome. About 70% of the 426 cubic meters is daily life water at households.

The water amount from the tap is 12 liters per minute, and you can reduce the amount to 5 liters if you use a cup when you brush your teeth. If you use a bucket instead of running water when you wash you car, you can reduce the water amount by 210 liters. Washing dishes by hands needs only one tenth of water amount needed by a dishwasher. If you wash dishes by your hands after three meals a day, you can economize as much as 300 liters a day. Demand for water-saving apparatus has been growing lately.

According to a questionnaire survey conducted the government, 39% of the respondents wish to buy a water-saving toilet system, 25% express the desire to buy a water-saving washer, and 19% think about introducing equipment of rainwater utilization. Flushing toilet has the larges share of 28% of water consumption in a household. It is followed by bath that accounts for 24%, cooking 23%, and laundry 17%. A Tokyoite uses about 240 liters of water in a day. It is possible to reduce water consumption greatly by using water-saving equipment and learning the behavior to economize water.

Japan can take pride in the state-of-the-art membrane technology and the management of water leakage. Besides, Japan can spread its traditional rules and customs for water saving worldwide. For example, water sprinkling on the road is one of Japan’s traditions to cool down the street. Whatever measures are taken, the attitude and behavior of each person are the strong weaponry for effective and efficient usage of water. (The end)