Retrofitting of the ammonia station in RWE’s power plant in Hamm

Power generation by coal-fired power plants produces exhaust air which is only discharged to the atmosphere after extensive purification. The target is to reduce nitrogen oxides, and this is implemented by DeNOx plants requiring the use of gaseous ammonia.

Being the largest electricity producer in Germany, RWE Power AG expands its coal-fired power plant in Hamm/Westphalia by two 800 MW class blocks (D/E). As a consequence, the existing ammonia station has to be expanded as well.
LT GASETECHNIK has received the order for performing this task.

The task package includes the procedural adaptation of the supply station for gaseous ammonia to the new conditions while conserving certain components of the station. The objective is to increase the availability of NH3 for the DeNOx operation in such a way that the required additional supply will be ensured at any time. For this, the ammonia station must be retrofitted and enhanced, redundancies must be created, and the plant must be linked to the new D/E blocks.

Two issues form also an integral part of the task package: Renewing the systems for condensate and auxiliary steam including related peripheral works, and laying of pipes for rainwater to re-circulate from the wastewater storage basin to the homogenization basin.

All these tasks are very challenging. Their complexity results in particular from the exigency of handling correctly large volumes of a critical medium for which absolute leak tightness must be ensured according to the Federal Water Act. Further difficulties arise from the necessity of conserving specific components of the existing station, and last but not least, from the fact that the retrofitting works on site allow only narrow time limits in order to reduce the downtime of the power station to a minimum.

 

The electrical and control equipment is implemented by Siemens according to the specifications of RWE’s engineering office. LT GASETECHNIK is in charge of performing complete detail engineering, producing or procuring the respective plant components and pipes, undertaking the retrofitting works, and after completion, re-commissioning the ammonia station.