Updated: July 2002
System for Decomposition of Dioxins in Flue Gas (DIOCATALYZER®)1. Outline of Equipment
This system enables the removal of dioxins by catalytic reaction which takes place on the surfaces of catalyst blocks in a honeycomb structure when the flue gas is passing through inside the reactor tower.
The catalytic decomposition reaction of dioxins occurs in the mechanism shown below, wherein dioxins are diffused into micro pores in the catalyst, absorbed on the surface of the catalyst, and then reacted in decomposition with the substances of the catalytic activity to form carbon dioxide, water, and hydrogen chloride.
Figure 1. Decomposition reaction of dioxins
2. Features
(1) This system provides an extremely high removal rate for dioxins with a high performance even at lower temperatures (less than 200ºC).
(2) Degradation of catalytic activity is low due to its three-component catalyst system (greater economic advantage).
(3) NOx can be removed simultaneously by adding ammonia.
(4) Reformation of dioxins can be avoided due to a decomposition of the benzene ring by oxidative decomposition reaction.
(5) This system can be installed on existing incinerator at low cost and with a short delivery time, and comply with the required flue gas standards.
Figure 2. Catalytic reactor combination example
3. Performance
According to measured data (Figure 3.; Initial performance data) in an existing incinerator with this Diocatalyzer, it shows that simply installing this catalytic reactor tower to a conventional process even at a low temperature condition provides a high decomposition rate at the level of 0.1 ng-TEQ/m3N
In case of joint installation of a active carbon absorbing unit with the scale up Diocatalyzer, its measured data (Figure 4.; Initial performance data) shows that the concentration ratio of dioxins can be reduced to a level of less than 1/10 - 1/100 of the regulated standard value.
Figure 3. Reduction of dioxins; Example (1)
Figure 4. Reduction of dioxins; Example (2)
4. Fields of application and types of waste materials for disposal:
This system can be installed on the existing plants such as incinerators for municipal waste or other combustion facility with its flue gas including dioxins and reduce the concentration of dioxins in the flue gas quite effectively.
5. Other information
The catalyst used in the DIOCATALYZER® is designed specifically for the decomposition of dioxins and consists of vanadium pent oxide and tungsten trioxide deposited on titanium oxide.
