ERC Emissions-Reduzierungs-Concepte GmbH products

In case of selective non-catalytic reduction (SNCR), ammonia reacts with the harmful nitrogen monoxide (NO) and nitrogen dioxide (NO2) from the flue gas into harmless nitrogen (N2) and water. The reaction temperature is 850 to 1,100 °C. In practice, urea-based ammonia-releasing reduction agents, such as the proven carbamin 5722 from ERC Technik, are the most suitable option available. The SNCR plants of ERC Technik essentially consist of the storage facility for the reductive agent, a metering unit and the atomisation equipment. The reductive agent is distributed in an aqueous solution into the flue gas Prior to the reaction chamber. The injection system is individually designed, thus, reaction always takes place in the correct temperature range.

In case of a selective catalytic reduction (SCR), ammonia reacts with the harmful nitrogen monoxide (NO) and nitrogen dioxide (NO2) from the flue gas into harmless nitrogen (N2) and water. The reaction temperature is 200 to 450 °C. In practice, urea-based ammonia-releasing reduction agents, such as the proven carbamin 5722 from ERC Technik, are the most suitable option available. SCR plants of ERC Technik essentially consist of metering and mixing sections, the atomisation equipment and the catalytic reactor, beeing equipped with up to four catalytic layers. In individual cases the catalytic converter can also be directly positioned in the flue gas channel. These systems can be arranged either downstream from the boiler (high-dust set-up) or after the flue gas cleaning (low-dust set-up). Re-heating of the flue gas prior to entry into the catalytic converter is usually necessary in case of the low-dust set-up.

ERC Technik combines the Advantages of the SNCR and SCR processes in the ERC-plus process. The ERC-plus process is applied if strict requirements are made on the secondary ammonia emissions (NH3 slip brake) and if NOx reduction rates are required which cannot be achieved by the pure SNCR process. The ammonia slip arising from the SNCR stage is used in the catalytic secondary cleaning stage for further nitrogen oxide reduction. Therefore, it can be guaranteed that the NH3 secondary emission is safely kept below 5 mg/Nm³. The catalytic layer is integrated into the boiler in such a way that the reaction temperature over the load range of the combustion plant is 350 to 400 °C.