Recently the circumstances of energy supply in our country is faced with difficult problems because of its expensive price. Therefore the economical use of energy is demanded as the national theme.
In our pulp and paper industries, which consume a lot of energy, it is so important probrem as we try to pressure the pollution. May in 1980, we edopted “YEW IPL” and O₂ control in our No. 3 Boiler for the purpose of the low excess-air combustion control.
The applicated digital-control engineering and the stable performance of O₂ sensor gave us the beneficial operation with maintaining about 1.061.08 of the air-excess ratio.
Actually its efficiency rised to the extent of 0.8 percent (we can save about one million and five hundred thousand yen a month in the cost of fuel), and also NO_x was decreased to the extent of 14 percent. Still more, we have been valuating the use of CO control since November in 1980.