Reducing the Amount of Waste Generated : Case Study Archives

Reducing sludge generated by treatment of waste water from silicon polishing (Fujitsu Integrated Microtechnology Ltd. Kyushu Plant) (FY2009)

Waste water containing sludge is generated during the silicon wafer back-polishing process, the first stage in product assembly. Without using chemicals, we were able to reduce the amount of silicon sludge generated to just one quarter of the previous amount by installing new equipment to concentrate and dry the waste.

Effort to Recycle Fluorite (FY2007)

While hydrofluoric acid is indispensable in semiconductor manufacturing, it also generates large amounts of sludge in effl uent wastewater processing. At the Fujitsu Microelectronics, Ltd. Mie plant, we succeeded in creating and recovering high purity fl uorite from wastewater with high concentrations of hydrofl uoric acid by adopting a revolutionary new technology. This new technology allowed us to reduce the amount of sludge generated by about 40%.
Furthermore the recovered fl uorite can be used as a raw material for making hydrofl uoric acid.

Biodiesel Fuel Reactor

PFU Ltd. installed a BioDiesel Fuel (BDF) reactor to refine waste cooking oil from the company cafeteria into biodiesel fuel for PFU-owned trucks, both to reduce waste and to replace the petroleum-based fuel that would otherwise be used.

Detailed information

• PFU ENVIRONMENTAL REPORT [Please see page 28]