Updated: July 2002
D-MAX System (The Equipment of Fixed Bed Type to Remove Dioxins)1. General Description
It is the system to remove dioxins including coplanar PCB (hereinafter called DXNs)with high efficiency in the combustion gas exhausted from incinerators, etc.
In the case that the air pollution control equipment in the front is of wet type, the fundamental flow diagram consists of mist-separator, duct-heater and adsorption tower, and in the case that the one in the front stage is of dry type, it consists of adsorption tower only but no mist-separator nor duct-heater is required.
Below is the general description of each equipment of D-MAX system :
1) Mist-separator
It is installed to protect the adsorption tower, that is the equipment to be located at the latter stage, from deteriorating the adsorbing capability due to the mist in the humidity-saturated gas.
The mist-separator is made from the resin element, that is of high efficiency, low pressure loss and excellent anti-corrosion, and it removes mist by means of the inertial collision.
2) Duct-heater
In the case that the adsorber, filled in the adsorbing tower at the latter stage, treats the gas in the saturated condition, it happens that the adsorber is not capable to work sufficiently due to the moisture. The duct-heater is installed to increase the temperature of the original gas, resulting in decreasing the relative humidity and to lead the gas to the adsorbing tower. It is structured not to get easily plugged with dusts etc. and that makes the stable temperature rise possible.
3) Adsorbing tower
The adsorbing tower is filled with the adsorbers, specially designed for DXNs use and removes by adsorbing the DXNs in the exhausted gas. The adsorber is designed for the purpose of adsorbing DXNs that own big molecular weight and is designed to have the extremely small hole distribution on its surface that is most suitable to adsorb DXNs.
2. Features
1) It absorbs DXNs in the exhausted combustion gas with high efficiency and provides the stable removal capabilities.
2) In comparison with the system which adopts the method of powdered activated carbons blown into the air pollution control equipment, D-MAX system requires less quantity of the adsorber, resulting in the saving of running cost.
And as the used adsorber is taken out of the adsorbing tower, apart from the fly ash, it is capable to be treated by being burnt in the incinerator.
3) As the adsorbing tower requires no driving part structurally, the maintenance work is easy.
4) It can be adopted to the air pollution control equipment of both wet type and dry type at the front stage.
5) D-MAX system is added later to the already-installed air pollution control equipment by means of slight reconstruction.
6) It does not require the PR-treatment equipment even in case that the high concentration dust (about 30 mg/m3N) comes into the adsorbing tower.
3. Properties
It is guaranteed that D-MAX system adsorbs DXNs in the exhausted combustion gas with a high removal
ratio and DXNs concentration shall be 0.1ng-TEQ/m3N or less at the exit of D-MAX system.
It shows the stable removal capability against the fluctuation of the entrance concentration and satisfies the regulation of dioxin exhaust, to be executed from December, 2002.
And it is also possible to confirm the result by the test equipment.
4. Field of application
Exhaust gas from an incinerator such as "Industrial waste", "Municipal waste", "Medical waste", "Waste plastic incineration", "Sludge".
