The German CHP specialist ETW Energietechnik has delivered natural gas CHP units with selective catalytic reduction (SCR) technology for the first time.
Stadtwerke Duisburg is the first user of Adblue technology from ETW. The family business from Moers comprises three plants with CHP engines of the type TCG 2020V12, each with an electrical output of 999 kilowatts.
Two of the three ETW plants with significantly reduced nitrogen emissions have been in operation since the end of 2017 – at the Duisburg-Mitte and Duisburg-Süd sites. The third plant in Duisburg-Süd will also be commissioned at the beginning of 2019, with all three plants achieving a very good overall efficiency of 94 percent each with an intelligent heat utilisation concept based on a second installed exhaust gas heat exchanger stage (AWT) and a heat recovery from the mixed cooling circuit.
Below all current limit values
With the fully operational, fully automatic SCR catalytic converter plant including urea injection (Adblue), the ETW plants comply with the latest state of the art and therefore fall below all currently required exhaust emission limits:
NOx: < 100 mg/Nm³ (exhaust gas dry at 5 percent O2)
CO: < 100 mg/Nm³ (exhaust gas dry at 5 percent O2)
Formaldehyde: < 20 mg/Nm³ (dry flue gas at 5 percent O2).
Highest environmental standards already met
From a legal point of view, compliance with the limit values from the „TA-Luft“ version of 2002 is still a legal requirement in Germany. It specifies that 500 milligrams of NOx, 300 milligrams of CO and 30 milligrams of formaldehyde per standard cubic meter must not be exceeded. The amendment to the TA-Luft of 2017 has been initiated, but has not yet been adopted. The new, higher limit values, which the ETW CHPs in Duisburg already comply with, are fixed here. These stricter values were written into the specifications by Stadtwerke Duisburg. By complying with the amended 2017 directive, utilities aim to generate their energy as environmentally friendly and sustainable as possible.
ETW Energietechnik‘s innovative Adblue CHP units are among the first SCR plants in Germany that are currently operating under full load on the grid. ETW managers are absolutely certain that others will follow and that Adblue will become the standard. „Usually, we currently only deliver the standard SCR catalytic converter housing with a single-nozzle section for Adblue with the elements for compliance with the values according to TA-Luft 2002. However, this simplifies retrofitting considerably and enables us to react immediately to customer requirements“,emphasizes the sales manager at ETW, Alexander Szabo.