Resources Utah IOF Steam Resources Steam Steam Generation Steam Distribution Steam End-Use Steam Recovery Steam Associations Utah Links Draining Condensate From Steam Process Heaters by JAMES R. RISKO, TLV America Corp., Charlotte, NC Searching for Steam System Efficiency by DAVID W. FISCHER, PE, Armstrong International, Three Rivers, MI Plant Engineering December 1996

Best Practices - Steam End-Use Tips Minimize Steam Flow Through PRVs Investigate potential to replace pressure-reducing valves with backpressure turbines in your steam system. In many steam systems, pressure-reducing valves (PRVs) are used to provide steam at pressures lower than generated from the boiler. This pressure reduction is an irreversible change resulting in lower pressure, higher super heat steam. Replacing PRVs with backpressure turbines that provide the low-pressure steam and generate electricity or shaft power uses the expansion to produce work. A detailed economic analysis must be performed to evaluate this type of opportunity. Recover And Utilize Available Condensate Determine how much of your available condensate you recover and utilize. Returning a substantial portion of your condensate to your boiler can have both energy and chemical treatment benefits: a) condensate is hotter than makeup water, so less energy is required to convert condensate to steam; and b) condensate requires significantly less chemical treatment than makeup water, so there are savings in chemical treatment costs associated with returning condensate. Returning as much condensate as possible also can help to reduce boiler blowdown (because fewer impurities are resident in condensate), and so minimize blowdown energy losses. Use High-Pressure Condensate To Make Low-Pressure Steam Investigate opportunities to utilize high-pressure condensate to produce useable low-pressure steam. An opportunity for utilizing high-pressure condensate is to allow it to pass through a flash tank and utilize the flash steam in low-pressure steam applications. The remainder of the condensate, now at lower pressure and temperature, can then be sent back to the boiler for use in producing steam. Maintain Heat Exchanger Efficiency Remove condensate and non-condensable gases from the steam space as fast as they form. Keep heat exchanger surfaces clean.