Water Resource Conservation

Basic Concept

The Nisshinbo Group's Business Conduct Guidelines include Awareness and Concern towards its environmental impact. The Group promotes water conservation, recycling, and other activities with an eye to improving the quality of resource recycling, and faithfully realizes a safe and secure society for all people. The Group manages key performance indicators (KPIs) as part of systematic measures to achieve its environmental target regarding reducing water consumption per unit of sales.

【Main measures】

  • ①Promoting water conservation activities through ISO 14001 activities
  • ②Expanding activities such as the introduction of water-saving equipment at manufacturing sites, reduction of water consumption and reuse of treated wastewater
  • ③Efforts toward sustainable water intake at overseas sites with different water availability conditions, such as use of rainwater and water recycling (returning to groundwater)
  • ④Activities in the Textiles business to purify well water that has been drained and deliver a portion of it to neighboring residents free of charge
  • ⑤Contributing to Japan and overseas wastewater treatment fields by providing microbial carriers for water treatment in the Chemicals business

Please refer to "Promotion System" in "Environmental Activities" for the promotion system.

Specific Initiatives of The Nisshinbo Group

Use of Water Resources

Nisshinbo Group's actual water use was 6,176 thousand m3, a 12% decreased from in the previous year. The volume of water used per sale was 12.0 m3 per million yen, a 13% reduction in the volume of water used per sale in the previous year. In the Textiles business, the amount of water used was reduced by improving water withdrawal methods.

The volume of water recycled was 967 thousand m3. This was an increase of 21% in the recycling volume of water in the previous year. In the Textiles business, the water used in the production of spunlace* (water-jet interlacing method) nonwoven fabrics is reused in air-conditioning facilities.

* Spunlace: Nonwoven fabrics produced by intertwining fibers through a high-pressure water flow.

Water Usage and Water Usage per Unit of Sales

Water Usage and Water Usage per Unit of Sales

* In 2018, we changed our fiscal year-end from March 31 to December 31. As a result, the consolidated fiscal year, which is a transitional period, is an irregular accounting period. For this reason, the period used for reference to FY2018 is adjusted to the period from April 1, 2018 to March 31, 2019, to match the period of other consolidated fiscal years.

Trends of Water Recycled

Trends of Water Recycled

* In 2018, we changed our fiscal year-end from March 31 to December 31. As a result, the consolidated fiscal year, which is a transitional period, is an irregular accounting period. For this reason, the period used for reference to FY2018 is adjusted to the period from April 1, 2018 to March 31, 2019, to match the period of other consolidated fiscal years.

Trends in Volume of Water Usage by Business

Trends in Volume of Water Usage by Business

*1 In 2018, we changed our fiscal year-end from March 31 to December 31. As a result, the consolidated fiscal year, which is a transitional period, is an irregular accounting period. For this reason, the period used for reference to FY2018 is adjusted to the period from April 1, 2018 to March 31, 2019, to match the period of other consolidated fiscal years.

*2 In fiscal 2019, the Electronics business was separated into the Wireless and Communications business and the Micro Devices business.

Understanding and Monitoring Water Risks

The Nisshinbo Group conducts water risk assessments of all of the Group's business sites and main supply chains using the AQUEDUCT Water Risk Atlas* published by the World Resources Institute (WRI).
As a result of the AQUEDUCT assessment, seven of the Group's business sites (Nisshinbo Mechatronics India Private Limited in India, Saeron Automotive (Beijing) Co., Ltd., Saeron Automotive (Yantai) Co., Ltd. and Shijiazhuang TMD Friction Co., Ltd. in China, and PT. Nikawa Textile Industry, PT. Nisshinbo Indonesia and PT. Naigai Shirts Indonesia in Indonesia) are classified as "Extremely high" areas.
At view point of the current water consumption at these sites, the Group estimates that it is not highly likely to have a significant impact on its business activities.
In addition, 11 sites of its main supply chain companies (Indonesian, Cambodian and Chinese business partners in Textiles business, and Chinese business partner in Automobile Brakes business) are classified as "Extremely high" areas.
The Group continues to monitor the situation of those sites and supply chains that have been assessed as "Extremely high.”

The Group has also assessed the risk from flooding as of 2050 in its climate change scenario analysis. The Group will promote risk reduction measures to deal with property damage and loss of business due to possible flooding.

* AQUEDUCT Water Risk Atlas: Maps based on 12 different water risk indicators, including "physical water stress," "water quality," "water resource regulatory risks," and "reputational risks."

AQUEDUCT Water Risk Atlas
AQUEDUCT Water Risk Atlas

CDP Water Security 2022 Evaluation

The CDP is an international NGO working in the environmental field. The CDP surveys more than 18,700 companies worldwide, assigning scores from A to D and more than 1100 cities, states, and regions to assess how CDP effectively responds to issues such as climate change, deforestation, and water security. The Nisshinbo Group received a "B-" rating in Water Security 2022.

CDP Water Security 2022 Evaluation
CDP Water Security 2022 Evaluation

Specific Activities of the Group Companies

Water Reduction Effects of Changing Sludge Recovery Facilities

NJ Components Co., Ltd., Sanyo Office, started sludge treatment by dehydrating polishing sludge containing processing water in the polishing process of its ferrite manufacturing division.

Ferrite cores must be polished to obtain the required performance. In the polishing process, processing water with a grinding agent added is used to mitigate cutting resistance, and the processing water is then circulated. The processing water used contains abrasive sludge generated during grinding. Therefore, it is necessary to separate the polishing sludge from the processing water in order to circulate it. In the past, a tank was installed in the processing water circulation route to allow the sludge to settle, and the settled sludge was periodically collected.

However, in this method, a large volume of processing water was disposed of along with the polishing sludge because the processing water in the tank was also discarded. In order to reduce the volume of water used, the sludge recovery method was changed from the conventional precipitation separation method to a dehydration separation method that removes the water from the sludge. This method made it possible to dispose only of the sludge that did not contain processing water, thereby reducing the amount of new processing water replenishment due to the disposal of processing water by 50%.

Sludge treatment by dehydration
Sludge treatment by dehydration

Reduction of Water Consumption by Renewal of Pure Water Facilities

Nisshinbo Micro Devices Inc., Kawagoe Plant, reduced water consumption by updating a resin tower (a facility that removes impurities from water through ion exchange to improve water purity), which is part of its pure water production facilities.

Pure water used in the cleaning process before and after each step in the semiconductor wafer process removes minute particles and dust from the wafer surface to prevent residues. Residues greatly affect the yield of product quality, so pure water is a very important part of the infrastructure. In the renewal of the resin tower at the facility that produces the pure water, the company changed to a compact, integrated resin tower in order to minimize the amount of water that is discharged and wasted in consideration of the environmental impact.

This will result in a reduction of approximately 18,000 m3 per year, a 28% reduction compared to the previous year, when the new system goes into operation at the end of FY2022.

Integrated resin tower
Integrated resin tower

Reduction of Water and Sewage Consumption for Production

Nisshinbo Micro Devices AT Co., Ltd., uses large volumes of pure water and tap water for wafer dicing (a manufacturing process in which wafers are cut to individual chips) and substrate dicing (a manufacturing process in which substrates with encapsulated devices are cut into pieces). In order to reduce wastewater consumption, a filtration system has been installed to collect and reuse wastewater from these processes.

The filtration unit uses hollow fiber membranes (a straw-like fiber membrane with one end closed and with countless ultrafine pores on the wall surface that remove impurities when pressurized water passes through them) in the filtration section, which is the heart of the filtration unit, and filtration through this device provides water quality better than that of tap water. By reusing the recovered water for transporting it to the manufacturing process, the company achieved a significant reduction in water consumption. In FY2022, 70,000 m3 per year was saved, and the same amount of sewage water was also reduced.

Installed filtration equipment
Installed filtration equipment

Recycling of Wastewater from Production Facilities

Nisshinbo Micro Devices (Thailand) Co., Ltd., in Thailand is stepping up its efforts to reduce water consumption. The ultrafiltration (UF) and reverse osmosis (RO) units recycle wastewater from dicing equipment for reuse as cooling water for different types of equipment, thereby reducing water consumption.

The ultrafiltration unit is used to recover high-molecular-weight substances and low-molecular-weight substances. Reverse osmosis is a method to separate extremely low molecular weight components and is used for water purification. The company attempted to recycle equipment wastewater by connecting the wastewater system of dicing equipment, which separates wafers with many ICs formed on them into individual chips, to the relevant unit.

This activity enabled the company to reduce the water supply to the cooling tower by approximately 19,176 m3 per year. In FY2023, the company will continue to promote the further recycling of wastewater from production facilities by changing the layout of the plant and consolidating the dicing equipment located in different areas.

Dicing wastewater tank
Dicing wastewater tank
UF tank to contain wastewater
UF tank to contain wastewater
RO unit for producing pure water
RO unit for producing pure water

Water Saving by Changing Operation of Vacuum Pump Heat Exchanger Cooling Water

Nisshinbo Chemical Inc., Tokushima Plant, uses a water-sealed vacuum pump to vacuum dry the reaction vessel after washing, which requires about six hours for the drying process. During this time, the water temperature of the circulating water for the water seal is important in order to maintain the vacuum inside the reaction vessel. If the temperature of the circulating water rises from the heat generated by the vacuum pump, bubbles will be generated in the water seal of the circulating water under negative pressure, which will adversely affect the vacuum inside the reaction vessel.

The vacuum pump heat exchanger has been operated with cooling water constantly supplied to suppress the temperature rise of the circulating water, but the company focused on the fact that the cooling water is unnecessary, except when the vacuum pump is in operation, and stopped the water supply during the vacuum pump shutdown period to save water. As a result, water consumption in FY2022 was reduced by 1,400 m3 compared to FY2021.

Utilization of Waterless Dyeing Technology by Improving Cotton Materials

The supercritical CO2 dyeing method is used for anhydrous dyeing of hydrophobic fibers, such as polyester. Anhydrous dyeing is an environmentally friendly and water resource-neutral dyeing technology that dyes fabrics without using any water at all in the dyeing process or generating contaminated water containing dyes. Because this process uses disperse dyes adapted to polyester, it was previously impossible to dye a natural fiber like cotton, which is hydrophilic.

Nisshinbo Textile Inc. developed a technology that makes it possible to dye fabrics made of hydrophilic cotton fibers using the supercritical CO2 dyeing method of hydrophobizing the hydroxyl groups of cellulose. Currently, a large volume of water is consumed in the dyeing process of cotton materials, and contaminated water containing used dyes is then discharged, but this development enables environmentally friendly waterless dyeing. Further research is underway to solve the issues of productivity, cost, and fastness toward practical application.

Reducing Wastewater Volume by Reusing Cooling Water

Nisshinbo Textile Changzhou Co., Ltd. in China is processing yarn-dyed shirts, mainly by form stabilization.

In the processing process of cooling dough, room temperature industrial water is poured into the cylinder rolls that come in contact with the dough for indirect cooling of the dough. In the past, the water used for this cooling was drained into a wastewater treatment facility.

After August 2022, the water for cooling is returned to the intake system. After filtering the used water, it is now softened by ion exchange and can be reused as industrial water. As a result, 704 m3 (46% of the total water used) out of the total water consumption of 1,547 m3 during the five-month period from August to December was reused.