3 Ways to Achieve Steam Boiler Efficiency
In the U.S. fruit and vegetable processing industry—which includes facilities that can, freeze, dry or dehydrate fruit and vegetable products—steam is king. Steam is the biggest end use of fuel in these types of plants, and steam boiler efficiency can result in dramatic savings. Steam boiler systems produce this versatile steam, which is then directed to a variety of applications such as blanching, peeling, heat sterilization, evaporation, pasteurization, indirect drying, container washing and equipment cleaning.
Achieving steam boiler efficiency can result in dramatic energy savings. According to the U.S. Department of Energy (DOE), a typical industrial facility that conducts a steam system assessment will identify potential steam system energy use and cost savings that range from 10 to 15 percent per year. There are numerous tweaks, upgrades, and retrofits that will make your steam systems more efficient, so what follows is a mere shortlist of improvements that offer substantial impact on your bottom line.
Steam Boiler Efficiency
Improved process boiler control is a no-brainer, particularly for larger boilers whose operating costs have the potential to make up the capital investment associated with efficiency improvements. Flue gas monitors maintain optimum flame temperature and monitor carbon monoxide (CO), oxygen and smoke. According to the Energy Star Guide “Energy Efficiency Improvement and Cost Saving Opportunities for the Fruit and Vegetable Processing Industry,” combining an oxygen monitor with an intake airflow monitor makes it possible to detect even small leaks. Amazingly, the guide states that a small 1 percent air infiltration will result in 20 percent higher oxygen readings.
By using more sophisticated controls, your plant can optimize the fuel/air mixture for high flame temperature (and thus the best energy efficiency) and lower air pollutant emissions. This measure can reduce natural gas consumption anywhere from 5 to 10 percent and result in a payback period of a little over a year.
Other measures to consider are properly sized boiler systems, improved boiler insulation and consistent boiler maintenance.
Steam Boiler Efficiency Measures
Typically, steam and hot water distribution systems are both extensive and complex. They can be major contributors to energy losses within a fruit and vegetable processing plant. The primary focus of your efficiency agenda is on reducing heat losses throughout the system and recovering useful heat from the system wherever feasible. Improved insulation and thorough maintenance makes a huge difference to a system’s efficiency performance. Additionally, regularly checking steam traps to ensure proper operation can save considerable energy for very little money. Without a diligent steam trap maintenance program, the guide reports, it is common to find up to 15 to 20 percent of steam traps malfunctioning in a steam distribution system. But once you incorporate a regular system of steam trap checks into your operations, your energy savings is conservatively projected as 10 percent.
In facilities with simultaneous heating and cooling demands, like those in the fruit and vegetable processing industry, applying process integration techniques can dramatically reduce facility energy consumption. For example, the heat rejected in a facility’s cooling process can be recovered and used in process heating applications. The savings can be substantial—and the payback period is typically 2 to 3 years.