The Process Unit (PU) is a fully assembled and factory-tested Mixing and Metering Cabinet designed for precise reagent preparation and distribution in SNCR and SCR applications. The cabinet incorporates all necessary piping, on-off valves, ball valves, flow transmitters, pressure transmitters, and associated instrumentation for ammonia, water, and instrument air services.

Based on the specific process requirements, the cabinet is equipped with dedicated injector module piping and individual flow measurement devices to ensure accurate reagent distribution and control to each injection lance or injector group.
A locally mounted Remote I/O panel is installed externally on the side of the cabinet and is fully prewired to all field devices. Locating the Remote I/O panel outside the cabinet maximizes the available internal space, allowing the installation of auxiliary equipment such as space heaters and exhaust fans when the unit is installed in hostile or extreme environmental conditions.

The Process Unit communicates seamlessly with the PetroNOx PLC via industrial communication networks including PROFINET, PROFIBUS, or Optical Fiber (OFC), enabling real-time monitoring, diagnostics, and advanced process control. The modular design ensures high reliability, ease of maintenance, and seamless integration with the plant automation system.