Solution for a water purification equipment manufacturer

Solution for a water purification equipment manufacturer


Player: Water purification equipment manufacturer

Issue: Impurities and dust in the ultra-pure water production equipment

Properties contributing to the solution: Low dust, low impurities, high strength and durability


The company is engaged primarily in the manufacture and sale of ultra-pure water production equipment. In response to strong demands from customers, its manufacturing division had decided to undertake the development of a new model that offered high performance in a more compact size and with lower frequency of maintenance. The development project was launched and the Division engaged in repeated prototyping. As the model was scheduled for development over a short period for reasons of market timing, development work was based on performing modifications to existing models as deemed necessary.

However, a problem occurred in the development of the filter component. When performance testing was carried out, impurities became mixed in at the initial stage, followed by many cases of dust appearing during longer use. The cause was the catalyst being used as a filter. Coconut shell was being used for cost reasons but there seemed to be problems with its strength and with impurities. The development team continued testing, changing the type of activated carbon and its combinations. However, the frequency of replacing the filled activated carbon increased. Maintaining filter performance meant increasing the size of the equipment, resulting in a design that failed to meet customer needs. No satisfactory results were forthcoming.

Key points of the issue

  1. Impurities contamination and dust generation were discovered in the process of developing the new model. Investigation revealed that the causes lay in the strength of the coconut shell-based activated carbon and impurities in the activated carbon itself.
  2. The development team repeatedly tested changes in the formulation and type of activated carbon, but the increased frequency of activated carbon replacement and the inability to reduce the equipment size failed to meet customer requirements.


  • Kureha’s BAC is activated carbon that combines outstanding strength and durability with low dust and impurities, reducing concerns over the elution of impurities, even during continuous use.
  • Its high bulk density and bead shape enable high-density filling, increasing flexibility in container shape selection and promising higher adsorption performance than the same volume of coconut shell-based activated carbon.

Comparing BAC with coconut shell-based activated carbon, the development team found that its characteristic strength, bead shape, durability, low dust, and low impurities were able to resolve these issues. Besides, the team discovered that BAC would make it possible to reduce the overall size. Its bead shape and high bulk density enable high-density filling with little restriction on the filling space. Along with greater flexibility in container form, a higher adsorption performance than the same volume of coconut shell-based activated carbon can be expected.

In the trial evaluations, the development team found that it could reduce the equipment’s space requirements by as much as 20%* through the use of BAC. They were also able to demonstrate that BAC itself was resistant to breakdown and that BAC could resolve the elution of impurities that had been an issue at the initial stage of use as well as the generation of dust during long-term use.
In cost calculation estimates, the team found that BAC provided a sufficient advantage when replacement frequency and waste disposal volume were taken into account.

*Calculated by Kureha Corporation based on JIS1474 carbon tetrachloride adsorption experiment results.

More information about BAC

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