EITec Environmental Technology Asia Sdn Bhd

The AmmoNOx System has been specifically designed for inert material flows generated by MOCVD processes, hydrogen (H2), nitrogen (N2), and ammonia (NH3) are present as pollutants. As this principle is based on oxidation, all polutants are precipitated at energetically favourable conditions which the process gas is electrically heated to the catalyst's inlet temperature, facilitating the conversion of pollutants. Utilizing hydrogen flow helps to reduce primary energy consumption. After passing through the catalytic converter bed, the gas enters the fan and can be directed into the exhaust line. Additionally, a secondary heat recovery system can be installed on the outlet side to harness residual energy. 

This method achieves clean gas values for NH3 and NOx that are well below the legally required values, whereas other procedures usually require a subsequent scrubbing method or clean gas dilution (so-called flue gas cooling). Optionally, a Metsorb adsorber for metal-organic compounds can be integrated into the systems and heat recovery systems.

Table of performance data:

Nitrogenous flue gas (from high-temperature combustion, purifying processes, etc.) is heated up via a heat exchanger by using hotter clean gas. The missing energy to reach the optimum inlet temperature of the catalyst will be supplied by gas burner or electric heating coil.

Following the heating device, the heated Nitrogenous flue gas is conditioned by injecting reagent through jets. The reagent is deposited to the catalyst and reacts with the NO and NO2 pollutants in the process gas and thus converts them. Hence, the NOx components are reduced.

After the process gas left the catalyst, it flows through the heat exchanger, where it releases part of its energy to the cold process gas to be preheated. In order to ensure an even inflow to the catalyst bed or to avoid wear & tear caused by dust, suitable components could be installed at the upstream of catalyst bed, if necessary. The process gas will be discharged via chimney by the downstream fan.

Depending on the application, a secondary heat recovery system could be added downstream of heat exchanger for further energy savings.

* The amount of additives required is monitored and evaluated continuously, ensuring that the prescriptive limits are never exceeded. 
* In advance, the process gas must be tested for catalyst toxins, otherwise the service life of the catalyst will be reduced.

Table of performance data

By means of a ventilator, the flue gas is fed into the combustion chamber, where it is heated to reaction temperature by use of a gas or oil burner or by an elelctrical heating element.
The ventilator can be positioned downstream or upstream of the combustion chamber (compression / suction facility). To reduce the primary energy consumption a flue gas / clean gas heat exchanger is installed. At the clean gas side, heat can be extracted to generate warm water, vapour or to heat up thermal oil.

Table of performance data
 

Located at the high-pressure side or suction side respectively, a ventilator transport exhaust air containing organic compound through the ETR compartment.

The ETR reactor consists of crude gas and clean gas valves, several chambers filled with ceramic heat accumulating material and a joint oxidation zone positioned above.

The crude gas valves direct the flue gas into one of the heat accumulation chambers, the gas temperature rises while it passes through. An oil or gas burner or electrical heating element in combustion area provides the energy required to facilitate the thermal reaction. The hot clean gas heats up another reservoir chamber. Thus being cooled down, it is fed through the clean gas dampers to the evacuation outlet. A PLC controls heating up and cooling down of the chambers alternately. The heat extracted from the chambers can be used to generate secondary heating.

Table of performance data.

Adsorption process to eliminate Cl2 from process gas. Once the container is filled with Cl2 the system switches automatically to the second container. The filled conatiner has to be disposed according to the local regulations.

The outlet concentration of Cl2 is continuouly monitored by a sensor which also controlls when the container has be switched.

Metsorb is a dry-bed absorption system that can separate diverse metal-organic compunds, depending on the specification.

Metsorb is a varioation that can be integrated into an AmmoNOx  / AmmoNOx light system, but it can also be used as stand-alone utility. An intergrated monitoring system constantly indicates remaining absorption capacities.

Table of performance data