Sharp Corporation plans to start using new, non-diluting nitrogen carrying wastewater treatment plant at its Fukuyama, Hiroshima Prefecture fab in July 2006. The treatment plant is the first of its kind in the semiconductor industry, which the company claims will remove at least 90 percent of the nitrogen in wastewater without dilution processes.
The technology is a combination of Sharp's micro-organism treatment
technique that purifies chemicals with a micro-nano-bubble technology
that activates and increases the number micro-organisms in the
controlled environment. Previously the use of micro-organisms for
nitrogen removal required a 10X dilution in heated water to be
According to Sharp, previous methods for treating nitrogen-containing wastewater included vaporizing wastewater by raising its temperature and using catalysts to break down the nitrogen, or concentrating the wastewater and disposing of it as industrial waste. Both methods added cost and contributed to further waste disposal efforts. The new technique doe not generate any sludge that would require disposal.
The new plant cost an estimated 440 million Yen, approximately $4 million US dollars.