U.S. droughts create increase benefits of condensate recovery
For commercial and industrial facilities the benefits of condensate recovery can be measured in several ways: energy reductions, increased operational efficiency, chemical treatment cost savings, water conservation and emission control.
This year the U.S. has seen a continuation of low rainfall and high temperatures, resulting in droughts across the country. Rain deficits have placed huge swaths of area across the country at risk of wild fires and agricultural output is being reduced significantly. Corn and soybean production has been reduced, affecting cattle feed and consumer prices. Cattle farmers and agricultural producers are short of water and residential consumers are asked to conserve. Industrial and commercial facilities are no different.
Should we expect to see these intense droughts and increased water rates in the future? Since 2010 the cost of water has increased by 18% in 30 major U.S. cities. The cost of water across the U.S. is increasing and water conservation is expected to be an important factor for years to come.
For commercial and industrial facilities the benefits of condensate recovery can be measured in several ways: energy reductions, increased operational efficiency, chemical treatment cost savings, water conservation and emission control. Steam, produced from chemically treated water, releases its heat energy on contact with a surface. This steam condenses back to water and still contains around 25% of its usable energy from the original unit of steam produced. Returning this hot condensate to the boiler leaves the boiler with less newly supplied energy to convert the water back to steam. This returned condensate can amount to huge fuel savings and emission control. Condensate recovery therefore saves energy by recycling heat energy, reducing the quantity of fuel and chemical treatments required to introduce and treat new boiler water.
Several different technologies exist to aid and control condensate recovery. The appropriately sized and selected steam trap removes condensate from a steam system while intelligently preventing the escape of live steam. There are many different types of steam trap, float and thermostatic, thermodynamic and balanced pressure, to name a few. The trapped condensate should be collected and pumped back to the boiler house feed tank. Mechanical steam driven pressure powered pumps automatically pump condensate as it is received. Pressure powered pumps maintain condensate temperatures as high as possible capturing the total available energy. Utilizing electrically actuated condensate return pumps are also a possible alternative. Flash steam recovery not only removes obvious steam plumes from facilities but also recaptures unused energy and reuses this energy in low pressure applications for pre-heating feed water or low pressure steam mains. In both instances the steam is being recycled for secondary purposes increasing the steam systems energy efficiency and reducing the quantity of steam produced by the boiler house.
Energy and chemical costs alone can justify condensate recovery projects, however adding ever increasing water costs can reduce payback periods significantly. Recovering and returning condensate will reduce water consumption. In times of drought when water is a scarce commodity, conservation through condensate recovery can move a business one step closer to self-sufficiency and will help a business become more sustainable and efficient.
Neil Davies is product marketing manager for Spirax Sarco. Content provided by Spirax Sarco, originally published in Steam News Magazine.