Chemco designs and manufactures storage, vaporization and flow control systems for anhydrous and aqueous ammonia. These systems are used to deliver ammonia vapor to selective catalytic reduction (SCR) reactors for the control of nitrogen oxide (NOx) emissions. These systems can also be used with boilers using selective non-catalytic reduction (SNCR) for the control of NOx emissions.
Storage systems consist of the required tank or tanks with all valves, instruments and safety devices required for operation. Truck unloading stations can be supplied as part of a storage skid or as separate skid-mounted stations for large tanks. Pumping systems can be included as part of the storage skid or as separate skid-mounted systems.
Vaporization systems for anhydrous ammonia can be natural circulation at the storage tank or forced circulation pumped from storage. Natural circulation systems draw liquid from the bottom and return vapor to the top of the storage vessel. Vapor to the flow control and dilution system is withdrawn from the top of the storage tank. Liquid ammonia is pumped to the forced circulation vaporization systems. Ammonia vapor is delivered directly from the vaporizer to the flow control and dilution system. Vaporizers can be electrically heated, steam heated or heated by condensate (hot water).
Ammonia flow control and dilution systems precisely meter the required ammonia flow and dilute it with air for delivery to the process. The flow control train typically consists of pressure regulation, flow measurement and flow control based on system demand. Ammonia is diluted and uniformly mixed with air in a static mixer. Flow control and dilution systems include all necessary instrumentation and safety devices required for operation.