Promotion of Resource Recycling (Waste Reduction) and Raw Materials Usage Reduction


To make effective use of limited resources, the KOBELCO Group implements measures to control waste. We add value to byproducts created during manufacturing processes, develop and introduce new applications for materials, and actively pursue recycling. The Group also reduces paper consumption by reviewing packaging specifications for products to be shipped for the reuse of packaging/shipping supplies, and by actively promoting digitization and IT adoption in documents used at office work across the entire Group.

Additionally, we have set recycling targets for main by-products, and are seeking to improve the recycling rate in order to reduce the final disposal amount.

Management Structure


We actively promote yield improvement and reduction of auxiliary material consumption. We have set the fiscal 2025 target of achieving a recycling rate of 99% for major by-products (slag, dust, and sludge).


The recycling rate of major by-products (slag, dust, and sludge) in fiscal 2021 was 99.3%. We will continue to work on raising the recycling rate of by-products and reducing final disposal amounts in order to achieve these targets.

In fiscal 2021, a total of 4.05 million tons of by-product materials were generated by the KOBELCO Group1 and the recycling rate was 96%. We will continue to reduce final landfill disposal volume by controlling the amount of by-products produced, increasing recycling, and developing new recycling technologies and offering added value.



  • 1 The information above covers 99% or more of the amount of by-products generated by the KOBELCO Group in Japan.

    2 Recycling rate = Amount of recycled resources / Amount of by-products

Amount of By-Products, Recycled Resources, and Landfill Disposal over the Past Three Years (including domestic Group companies)1

  Fiscal 2019 Fiscal 2020 Fiscal 2021
Amount of by-products (t) 4,118,779 3,188,926 4,051,021
Amount of recycled resources (t) 3,912,532 3,021,888 3,901,504
Amount of landfill disposal (t) 180,808 135,923 119,932
Other (volume reduction, t) 25,439 31,115 29,585
By-product recycling rate2 95% 95% 96%
Amount (rate) of specially controlled industrial waste generated (%)3 21,986(0.53%) 23,949(0.75%) 21,136(0.52%)

Transportation Amount of Specially Controlled Industrial Waste Disposed of over the Past Three Years* (including domestic Group companies)

  Fiscal 2019 Fiscal 2020 Fiscal 2021
Transportation amount of specially controlled industrial waste (t) 19,356 15,656 16,935

Main Resources Used at Kobe Steel, Ltd. over the Past Three Years

Main Raw Materials Unit Fiscal 2019 Fiscal 2020 Fiscal 2021
Iron ore 1,000 t 10,380 9,310 10,470
Coking coal / coke 1,000 t 5,360 4,920 5,340
Aluminum ingots, copper ingots, etc. 1,000 t 430 430 490
Total 1,000 t 16,170 14,660 16,300

Initiatives of the KOBELCO Group

Controlling Waste Generation and Promoting Recycling

Of the by-products produced, steel slag, which is produced in large amounts, is recycled more than 99% into construction and other materials, thereby contributing to a recycling-oriented society. Most steel slag products are designated as specified procurement items under the Act on Promoting Green Procurement for public work projects as materials that benefit environmental conservation. Going forward, we will continue to expand the applications of steel slag products that contribute to carbon neutrality and biodiversity.

Application Details
Cement materials Granulated blast furnace slag is pulverized and mixed into ordinary cement as a raw material for cement. This reduces CO2 emissions generated in the cement manufacturing process because the firing process of clinker, an intermediate product of cement, is no longer required.
Roadbed materia Roadbed material is made by pulverizing/granulating steel slag and ash stone. It has hydraulic properties and provides strong support. The roadbed material can contribute to conservation of the natural environment by being utilized as a substitute for natural resources.
Ground improvement material By replacing cement stabilizers with steel slag, it is possible to build a robust ground base at low cost, contributing to national resilience and reducing CO2 emissions during material manufacturing.
Steel slag artificial stone Steel slag artificial stone is a form of artificial stone made by solidifying steel slag with cement. Steel slag is expected to make a contribution to absorb and hold CO2 by helping to restore marine resources by providing nutrients in the form of iron and other substances contained within the slag to encourage luxuriant seaweed growth. Steel slag is already being used in submerged bank construction work contracted by the City of Kobe.

Major Initiatives in the Business Divisions (Japan)

Business Division Examples of Initiatives to Reduce the Generation of By-Products/Waste and Decrease Landfill Disposa
Steel & Aluminum
  • Reduction of steel slag generation and development of new applications
  • Development of recycling technologies for dust
  • Recycling of arc furnace ash
  • Reuse of aluminum scrap generated in the plant
  • Recycling sorted waste flux into roadbed material and cement material
  • Reuse of product packaging materials
Advanced Materials
  • Reduction of steel slag generation and development of new applications
  • Reuse of aluminum scrap generated in the plant
  • Reuse of shipping boxes for machinery by strengthening packaging materials
Electric Power
  • Recycling of coal ash and gypsum, which is a by-product of flue gas desulfurization equipment
  • Study on facilities underway to utilize sewage sludge fuel

Initiatives at Overseas Group Companies

Company Name Examples of Initiatives to Reduce the Generation of Waste and
Decrease Landfill Disposal
Kobelco Spring Wire (Foshan) Co., Ltd. (KSW) Reuse of lubricants and sand
Kobelco Automotive Aluminum Rolled Products (China) Co., Ltd. Reuse of pallets, reuse of packing PT bands
Kobelco Aluminum Products and Extrusions, Inc. (KPEX) Recycling of waste oil
Kobe Aluminum Automotive Products (China) Co., Ltd. (KAAP-C) Reuse of cut chips and waste reduction by adding sludge treatment equipment
Hangzhou Kobelco Construction Machinery Co., Ltd. (HKCM) Reducing waste by compressing paint sludge
Kobelco Construction Machinery (China) Co., Ltd. (KCMC) Reduction of the volume of sludge by compressing and drying it
Kobe Aluminum Automotive Products, LLC (KAAP) Reuse of aluminum scrap

Initiatives to Control Waste Generation and Recycling in Collaboration with Outside Entities

Initiative Details
Initiatives to effectively use underutilized energy in local communities
—From turning wastewater sludge into fuel to producing and supplying hydrogen
  • Kobelco Eco-Solutions Co., Ltd., which has wastewater sludge treatment technology, and Kobelco Power Kobe Inc. (the Kobe Power Plant), which operates coal-fired power plants, plan to turn wastewater sludge into fuel and use it as wastewater biomass fuel at the power plant. (As using wastewater sludge biomass is an appropriate method for the pulverized coal-fired power generation business.)
  • We plan to use wastewater sludge biomass fuel as a portion of the fuel for generating electric power to produce hydrogen, which will be supplied to fuel-cell vehicles (FCVs). This initiative will contribute to the spread of FCVs, reduction of CO2 emissions in local communities, and improvement in air quality
  • For more information, please see the following:

Study group for expanding usage of steel slag
  • In a study group established by Hyogo Prefecture (Hyogo Eco-Town Promotion Council), we are conducting research to expand the use of steel slag in industry-government-academia collaboration/cooperation. The KOBELCO Group participates as a member of the following research working group.
  • The Construction Method for Disaster Risk Reduction Working Group aims for the practical utilization of low-cost and effective reinforcement method for old road fill, whose aseismatic performance is decreased. Working toward actual use of fill mixed with steel slag, we are conducting aseismatic reinforcement tests using it.
  • For more information, please see the following:

Initiatives to Control and Recycle Industrial Waste Containing Plastic Products

In addition to controlling the occurrence of industrial waste containing plastic products, the Group outsources processing to a provider that recycles these materials and recovers waste heat from them. Looking ahead, we will continue with our initiatives to control occurrence and recycle these products.

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