NOx according to BImSchV: while others just monitor NOx, we actually control it!

Current data analyzes from the Sentinel-5P ESA environmental satellite show: we can breathe a sigh of relief. Global nitrogen oxides have declined significantly over the past few months. Researchers, however, view this decline as a short-term effect of the strict quarantine measures used to contain the Covid-19 virus. The goal thus remains: long-term improvement in air quality. After all, nitrogen oxides (NO_x) are the number one air pollutant in most cities. As a result, Europe has significantly tightened its emissions standards for nitrogen oxides. Many countries requires detailed NO_x monitoring from plant operators. In the case of diesel and gas engines, this requirement is usually met though the use of small NO_x boxes that continuously measure and record the amount of nitrogen oxide in the exhaust gas.

Yet this method alone only solves half of the challenge for many plant operators, since simple monitoring does not change the NO_x values of the engine. To benefit communities and the environment, technical NO_x solutions must actively regulate the process to ensure that fewer nitrogen oxides are actually emitted and the prescribed limits are consistently met.

Our intelligent E²CORE-control+ multivariable controller, which features inputs for two broadband lambda probes and an interface for up to two NO_x probes, takes care of regulating probe operation, processing measurement data and continuously monitoring the probes. It can do so as a standard control component in our E²CON-CHP engine and CHP control system, for example. Based on operating data from the gas engine and the NO_x measurement, the E²CON-CHP corrects the mixture control, determines the necessary amount of AdBlue (aqueous urea solution) and then transfers that amount to the SCR system. In this way, the control system intervenes directly in the regulation of the engine and ensures:

• Lower risk of exceeding NO_x limits, which forces operators to intervene or report to authorities
• The engine does not need to be operated with a safety margin from the NO_x limits and therefore runs more reliably and with higher efficiency
• All NO_x and SCR measurements are recorded in the engine operating history, appear in snapshots from the E²SERVICE software and are available for high-resolution diagnostics. To enable this, the E²CON-CHP eninge control system transfers the encrypted measurement values to the AVAT CLOUD.
• In the AVAT CLOUD, data from all connected systems, including data supplied by conventional NO_x boxes, are stored for a minimum of 6 years. The data can be accessed from any computer with an internet connection and are password-protected.

More information on our system can be found here: AVAT NO_x-control