For Consumer / IoT
Recognizing the importance of the global environment, RICOH Electronic Devices puts great emphasis on environmental protection in our business operations of providing the products.
|June 4, 1997||Yashiro Plant obtained certification.|
|Nov. 28, 1997||Yashiro Plant and Ikeda Office established the total integrated system and obtained an extended ISO14001 certification from Japan Quality Assurance Organization (JQA). This is the 12th certification in Ricoh group.|
|June 23, 2000||Shin-Yokohama Office and RICOH System Center including the design section obtained ISO14001 certification from JQA.|
|Feb. 9, 2007||Integrated Certification obtained as RICOH|
|Dec. 20, 2019||Shift from RICOH integrated certification to our individual certification.|
|Certification body||JAPAN QUALITY ASSURANCE ORGANIZATION|
Semiconductor production consists of a series of between 200 and 300 processes, and since at every stage impurities are washed away from the product (silicon wafers), vast quantities of water are required. At the Yashiro Plant, which handles the production of our semiconductors, we have been using a highly efficient water recycling system since the plant came online in 1989, with the objective of thoroughness in the effective use of water.
The processing of the wafers takes place in a clean room, at which stage ultra pure water is employed. The water from the water pipes is flushed through a pure water production system, in which after initial and then secondary treatment it is turned into ultra pure water and supplied to the production line. The water used on the production line (principally for cleansing wafers) is recovered in the drainage line after being divided into three grades according to the level of impurities it contains. After passing through the pure water collection and processing system the Level 1 drainage water with a comparatively low amount of impurities in it is returned to the pure water production system, and is used again as ultra pure water. By passing the Level 2 drainage water through the pure water collection and processing system it once again becomes pure water (of a lower grade than ultra pure water), and this is used in boilers and as cooling water for freezing units. The Level 3 drainage water undergoes neutralization treatment in the effluent treatment system, and is then flushed down the sewage pipes.
Furthermore, water other than the water used to cleanse wafers that is processed by the water recycling system is also subject to recycling activities. For example, the sampling water used to measure dissolved oxygen in once-through boilers is generally flushed away after measuring, but it is now possible for us to reuse it in boilers. When doing so, by altering the position of each device the water is returned to a water supply tank using the difference in elevation, making it possible to reuse the water without any pumps or energy.
These activities have led to an overall water recycling rate of 65.6%, which means we have reduced the amount of water used on an annual basis by 337,000 m3 (actual performance in FY 2018).
In the semiconductor manufacturing process, a large amount of nitrogen is consumed.
Nitrogen is a very stable inert gas, and is used as dilution gas during wafer processing and as purge gas for safe handling of specialty gasses.
Previously, liquid nitrogen was transported by tank truck and gasified at our factory before being used. According to the method, there was energy consumption for liquefying nitrogen in the transportation and fuel consumption of tank truck in transportation. In order to reduce such environment loads, in 2009 we installed On-site Nitrogen Generator that purifies only nitrogen from the air.
Nitrogen is the most abundant gas in the air, and the concentration is 78%. The nitrogen purification method by On-site Nitrogen Generator is "Cryogenic separation method".
As the procedure, 1) to remove impurities by compressing air, 2) to cool it down to around -180 degrees by using a heat exchanger, 3) to refine high purity nitrogen in the rectification column by utilizing the difference of boiling points of oxygen (-183 degrees) and nitrogen (-196 degrees).
Due to the installation of On-site Nitrogen Generator, although CO2 emissions increase in our factory, we can reduce the total amount of CO2 (Life cycle CO2) by reducing energy consumption for liquefying nitrogen in the transportation and fuel consumption of tank truck in transportation. Actually we can achieve the reduction of 3,360 t-CO2 per year.
Moreover, we can reduce the purchase and transportation cost of liquid nitrogen. And also we can eliminate the risk of nitrogen supply instability in unexpected circumstances like disasters.
On-site Nitrogen Generator brings the stable operation of our Fab, and also contributes to the providing customers with quality and reliability.
The Nisshinbo Group aims to enhance its corporate value through the practicalapplication of its corporate philosophy, “Change and Challenge! For the creation of the future of Earth and People. We will contribute to safe and secure livelihoods as an Environment and Energy Company group, not only by proposing newproducts and systems that realize environmental preservation, energy conservation, and alternative energy, but also by offering solutions to problems that humansociety is facing like environmental destruction and disasters caused by climate change.