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Data Entry: September 2011
Name of recycling technology Recycling of Various Waste Paper Containing Foreign Matter
Name of recycler San-Ei Regulator Co., Ltd.
Location Kawasaki City, Kanagawa Prefecture
Name of eco industrial park Kawasaki Zero-Emission Industrial Complex
Receiving waste materials for recycling Various waste paper materials (mixed office waste paper, confidential documents, beverage cartons, used tickets, etc.)
Recycled products/recovered materials Toilet paper
Capacity of recycling plant 90,000 t/year
Area of recycling plant 18,351 m2
Number of employees in recycling plant 120
Start of recycling operation 2003
Technical description Various waste paper materials containing foreign matter including plastics, clips, and staples are dissolved, and foreign matter and ink are removed, then recycled toilet paper is manufactured.

Recycling process

The recycling process consists mainly of the following processes:

  • Dissolution process
    Collected waste paper is fed into the pulper, mixed with water for swelling, and dissolved into pulp slurry to facilitate the separation of foreign matter.
    Cardboard boxes containing confidential documents are directly fed into the pulper for immediate dissolution without opening the boxes, to ensure secure disposal of documents and prevent leakage of confidential information.
  • Screening process
    The pulp slurry is fed into the liquid cyclone, in which foreign matter including metals and plastics are removed by centrifugal force. Then, pulp sludge is removed from the pulp slurry through the primary, secondary, and tertiary screens.
    Removed plastics and pulp sludge are incinerated in the heat recovery boiler, and the recovered heat is used as thermal energy for drying paper in the paper-making process, etc.
    Removed metals are sold as raw materials for steel manufacture.
  • De-inking process
    After foreign matter is removed, a specific amount of bubbles is injected into the pulp to remove ink from the pulp fiber.
  • Sterilization and bleaching process
    Fine stains in the pulp fiber are washed out in 8 to 12 hours before the pulp is sterilized.
  • Paper-making process
    The thinned-out paper is sterilized and dried at high temperature, and wound onto a roll.
  • Finishing process
    The recycled paper is embossed, rewound for different sizes, trimmed to product sizes, packaged, and bagged.
Technological features

  • Waste paper containing foreign matter including clips and plastics can be directly recycled without separation. Waste paper contained in cardboard boxes can be directly recycled without opening them.
  • The recycling process achieves zero emissions as follows:
    - Plastics and pulp sludge removed in the recycling process are burnt as fuel in the heat recovery boiler, and recovered heat is used in the recycling process.
    - Wastewater generated in the recycling process is treated in the recycling plant, paper sludge generated in the wastewater treatment process is used as fuel for the heat recovery boiler, and the treated water is used to generate electric power by utilizing the gravitational force of water when discharged.
    - Incineration ash generated in the heat recovery boiler is sold to a cement plant in the same coastal area of Kawasaki City as a raw material for cement.
    - Metals removed in the recycling process are sold to a steel works in the same coastal area of Kawasaki City as a raw material for steel manufacture.

Background of starting recycling business and participating in eco-town program
  • Originally engaged in the waste paper recycling business
    The company's original business is manufacturing equipment for making paper and recycling waste paper. The company then entered the business of recycling waste paper into toilet paper in partnership with a paper-making company (one of its group companies).
  • Established technologies already available for recycling waste paper containing foreign matter
    - The group started the waste paper recycling business in the early 1960s, but securing waste paper (raw material for recycling) was a major challenge for the company because competitors had already entered the same business.
    - At that time, waste paper containing foreign matter such as metals and plastics was landfilled or incinerated without being recycled, so the company started to develop technologies for recycling this type of waste paper, and in 1994 developed a foreign matter removal system for the waste paper recycling process. This technology was awarded the Director-General of the Science and Technology Agency Prize in 1995.
    - This technology enables secure disposal and recycling of confidential documents from such as business corporations and government offices by using dissolution treatment.
    - Because the company was involved in the waste paper recycling business with such technologies, the Japan Environment Corporation (a government-affiliated organization) invited the company to participate in the Eco-town Program of Kawasaki City. At first, the company took part in the program to deliver plants ordered by the Japan Environment Corporation, then later the company directly participated in the program instead of the Japan Environment Corporation at its request.
Fund procurement The initial investment by the Japan Environment Corporation was about JPY5 billion, of which JPY2.1 billion was subsidized by the national government. 
Major success factors
  • High level of interest in the environment by the top management
    The owner of the corporate group (Corelex Group) is strongly interested in the environment. The group's motto for the business is "paper-to-paper recycling."
  • Development and accumulation of original technologies within the corporate group
    Various original technologies and expertise for recycling waste paper and manufacturing paper have been developed and accumulated within the corporate group. The technology to manufacture coreless toilet paper has been patented in 47 countries.
  • Receiving waste paper containing foreign matter
    A separation system was developed to recover only paper fiber for recycling from waste paper containing plastics and clips, etc. This system makes it possible to (i) recycle mixed office waste paper, beverage cartons, used tickets, etc. that were previously incinerated and disposed of, and (ii) securely process confidential documents contained in cardboard boxes without opening them.
  • Transportation of waste paper and recycled products
    Because the recycling plant is located in the Tokyo metropolitan area, the distances for transporting waste paper and recycled products are shorter, thus reducing transportation costs and environment impact.
Issues and Challenges
  • Securing a lot of water at a lower cost
    Paper manufacturing needs a lot of water, so it was important to secure water at a lower cost. The matter was discussed with Kawasaki City Government and arrangements were made so that advanced treated water from a sewage treatment plant in the city can be used at the plant. This is the world’s only paper-making plant that utilizes advanced treated water (reclaimed water) for industrial use.
  • Securing waste paper for recycling
    - There is high demand for disposal of confidential documents and mixed office waste paper from the many business corporations and government offices located in the Tokyo metropolitan area. As part of efforts to secure waste paper (raw materials for recycling), the company visited such business corporations and government offices to explain the ability of secure disposal and recycling of confidential documents. Today, the company receives confidential documents and mixed office waste paper from about 2,500 business corporations and government offices.
    - The company is implementing closed recycling with business corporations with high CSR. (i.e., The company receives waste paper from the business corporations, and the business corporations purchase recycled toilet paper from the company.) For these corporations, original patterns and designs can be printed on toilet paper, which is used in restrooms of event venues or sales areas (such as supermarkets) as part of corporate PR campaigns and CSR initiatives.
    - The company also receives confidential documents and mixed office waste paper from highly eco-conscious local governments outside the Tokyo metropolitan area.
    - The company purchases beverage cartons, leaflets, and pamphlets collected by women's groups and institutions for disabled persons, and sells toilet paper to them at low prices. Such waste paper helps stabilize the collection of waste paper and the operation of the recycling plant, although the activity does not make a profit.
Future prospects
  • The purchase price of waste paper has been increasing due to the following factors:
    - Less paper manufactured by paper manufacturers due to the shift to IT and paperless solutions
    - Increased export of waste paper to China and other countries
  • The promotion of waste paper recycling in a region or country (closed recycling) is greatly affected by the policy or vision of local governments.
  • It is necessary to meet the following conditions for a successful waste paper recycling business:
    - Procuring large volumes of inexpensive waste paper
    - Securing large amounts of inexpensive water and a stable supply of electric power required in the paper-making process
  • In developing countries, waste paper may already be collected as valuable resources for recycling. Thus, a detailed study must be conducted in advance as to whether recyclable materials can be secured.

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