Press Releases


December 8,2004

Sales launch of decomposition agent for fly ash dioxins "DIOVANISH™UF"

Kurita Water Industries (HQ: Shinjuku, Tokyo, President: Hiroshi Fujino) has developed and launched sales of a decomposition agent for dioxins, "DIOVANISH™UF", that is designed for heating dechlorination systems, for dioxins in fly ash.


"DIOVANISH™UF" is a decomposition agent used for treating dioxins in fly ash (which is emitted from incinerators) through heating dechlorination systems. The current decomposition of dioxins requires heating at 450 to 500℃, but our new "DIOVANISH™UF" is an innovative agent that, when mixed with fly ash, efficiently decomposes dioxins at lower temperature between 350 and 400℃. "DIOVANISH™UF" makes stable treatment of dioxins a reality, leading to substantial cost reductions in energy and maintenance.


1. Development background

The special act of dioxin countermeasures was published in December of 2002, making mandatory the individual treatment of fly ash, which used to be disposed with incinerated ash (burnt residue). The new law also stipulates that incinerators installed on or after January 15, 2000 must maintain the amount of dioxins in fly ash and incinerated ash below 3ng-TEQ/g each. With the growing number of customers needing help in reducing the amount of dioxin emissions (through flue gas, fly ash and bottom ash) from incinerators, there has also been a higher need for treatment of dioxins in fly ash, which occupy 70 to 90% of the total emissions.

The thermal decomposition process with heating dechlorination systems is considered to meet the standards for the reduction of dioxins, and is actually capable of reducing dioxins to a level below the standard value. However, in this process, stable treatment of dioxins is only completed by heating at 450 to 500℃ or more, resulting not only in potential malfunctions caused by the adhesion of melted low-melting-point salts to the system, but also considerable corrosion of system materials, depending on the property of fly ash. Decrease of heating temperature below 400℃ may be regarded as a way of sidestepping the above problem, but this allows the active resynthesis of new dioxins instead of their decomposition, raising the urgent necessity for a more fundamental solution.


  • 1) Characterictics of "DIOVANISH™UF"
    1. a)Speeding up of dechlorination
      "DIOVANISH™UF" makes dechlorination easier, speeding up the decomposition of dioxin.
    2. b)Prevention of resynthesis
      Copper chloride in fly ash is known to act as a strong catalyst for resynthesis of dioxins. "DIOVANISH™UF" makes copper chloride inert and as a result, prevents from resynthesis.
    3. c)Extremely harmless
      "DIOVANISH™UF" is highly safe agent.
      There is no odor, and even its decomposition side products are harmless, causing little effect on the surrounding environment.
    4. d)Expanded versatility
      Constant superior results are obtained regardless of the properties of fly ash or the type of dechlorination system.
  • 2) Advantages of "DIOVANISH™UF"
    1. a)Long-lasting stable operation of heating dechlorination systems
      The removal of dioxins at lower temperatures, 350 to 400℃, not only reduces high-temperature-specific malfunctions, but also allows long-lasting stable operation of the heating dechlorination system. A further advantage is cutbacks in running costs for heating and maintenance.
    2. b)No rapid cooling system is needed after heating treatment
      As this decomposition is irreversible, the rapid cooling system after the treatment is no necessary. Therefore, downsizing of heating dechlorination system is quite possible.

3. Our target market

The market for "DIOVANISH™UF" is presumed to be about two billion yen a year, considering the fact that approximately 70 local governments and corporations have incorporated heating dechlorination systems. With the prospect of an increasing number of local governments and corporations that will phase the systems in to be compliant with the special act of dioxin countermeasures, the market to which "DIOVANISH™UF" is applicable is presumed to eventually expand to five billion yen a year. Estimated annual sales will be 500 million yen in five years.

4. Further business development

Kurita Water Industries has already engaged in the development and sales of incinerator-related products such as the dioxin inhibitor for exhaust gas "SHINESTAR™Series", the sophisticated acidic gas processing agent "HIGHPURSER™Series", and the heavy metal immobilization agent in fly ash "ASHNITE™". The addition of our new innovation, "DIOVANISH™UF", makes it possible for us to deal with an even wider range of customer needs, allowing us to further expand our operations in the area of dioxin treatment.