Even with the best pretreatment programs, boiler feedwater often contains some degree of impurities, such as suspended and dissolved solids. The impurities can remain and accumulate inside the boiler as the boiler operation continue, leading to carryover of boiler water into the steam, causing damage to piping, steam traps and even process equipment. The increasing concentration of suspended solids can form sludge, which impairs boiler efficiency and heat transfer capability.
One way to improve efficiency is to review your blowdown practices. This includes the use of an automatic blowdown control system by regulating water volume discharged in relation to the amount of dissolved solids present. This system maintains proper water chemistry within acceptable limits, while minimizing blowdown and reducing energy losses. Cost savings come from the significant reduction in the consumption, disposal, treatment, and heating of water.
The U.S. Department of Energy's Industrial Technologies Program calculated annual cost savings associated with the installation of an automatic blowdown control system that reduced blowdown rate from 8% to 6%. The example below assumes a continuously operating natural gas-fired, 150 psig, and 100,000 lb/hr steam boiler. Makeup water temperature of 60 degrees, with boiler efficiency of 83%, with fuel valued at $3.00 MMBTU was used, and the total water, sewage and treatment costs are $0.004 per gallon.
The annual cost savings in the example above equals:
Boiler Feedwater:
Initial = 100,000 / (1-0.08) = 108,695 lbs/hr
Final = 100,000 / (1-0.060 = 106,383 lbs/hr
Makeup Water Savings = Initial - Final, or 108,695 lbs/hr - 106,383 lbs/hr = 2,312 lbs/hr
Enthalpy of boiler water = 338.5 Btu/lb; for makeup water at 60 degrees = 28 Btu/lb
Thermal Energy Savings = 338.5 - 28= 310.0 Btu/lb
Annual Fuel Savings = 2,312 lbs/hr x 8760 hrs/yr x 310.5 Btu/lb x $3.00/MMBtu / 0.82 x 106 = $23,007
Annual Water and Chemical Savings = 2,312 lbs/hr x 8760 hrs/yr x $0.004/gal / 8.34 lbs/gal = $9,714
Annual Cost Savings = $23,007 + $9,714 = $32,721
If you need additional information about feedwater systems or other ways you can decrease costs, contact Nationwide Boiler today and we are happy to discuss ways to improve your bottom line: 1-800-227-1966.
Boiler Blog | Nationwide Boiler Inc.
Nationwide Boiler receives progress update reports via email from the Department of Energy's (DOE's) Office of Energy Efficiency & Renewable Energy (EERE). Over the last few weeks the department has been busy promoting aggressive actions to promote new initiatives that they hope will save consumers money and create new jobs.
One horsepower (HP) of electricity is equal to 0.746 kilowatt-hours. A 1 HP motor running at full load for 24 hours would use 17.90 kilowatt-hours of electricity.
Now that you are able to determine your electric consumption for your auxiliaries, you can use that information to decide if additional energy efficiency upgrades are needed. Every little bit counts!
Last week the White House announced an executive order supporting Combined Heat & Power (CHP) and industrial energy efficiency. The order calls for a national combined heat and power deployment goal of an additional 40 GW by 2020.
CHP systems can reach efficiencies above eighty percent (80%) and currently supply twelve percent (12%) of U.S. energy capacity. There is approximately 82 GW of CHP installed in the U.S. and industry estimates indicate the technical potential for additional CHP at existing sites in the U.S. is approximately 130 GW (plus an additional 10 GW of waste heat recovery CHP).
Investments in industrial energy efficiency, including combined heat and power, offer significant benefits to manufacturers, utilities and communities across the country, including:
- Manufacturers could save at least $100 billion in energy costs over the next decade, improving U.S. manufacturing competitiveness.
- Meeting the 2020 goal could mean $40 to $80 billion of new capital investment in American manufacturing facilities and helps to create jobs.
- Offering a low-cost approach to new electricity generation capacity to meet current and future demand: Investments in IEE, including CHP, cost as much as 50% less than traditional forms of delivered new baseload power.
- Significantly lowers emissions: Improved efficiency can reduce nationwide GHG emissions and other criteria pollutants.
USCHPA Executive Director, Jessica Bridges, said "CHP technology can be deployed quickly, cost-effectively and with few geographic restrictions. Establishing this national goal toward greater CHP deployment will significantly advance cleaner energy generation in the U.S., benefit the environment, and help create much-needed manufacturing and industrial jobs. I applaud the White House for its efforts to support clean power generation through CHP and pledge the combined heat and power industry's support to help achieve this goal."
USCHPA is a trade association whose membership includes manufacturers, suppliers, and developers of combined heat and power (CHP) systems. CHP lowers demand on the electricity delivery system, reduces reliance on traditional energy supplies, makes businesses more competitive by lowering their energy costs, reduces greenhouse gas and criteria pollutant emissions, and refocuses infrastructure investments toward next-generation energy systems. CHP is a proven and effective energy resource that can be immediately deployed to help address current and future global energy needs by incorporating commercially available and domestically produced technology. For more information, visit www.uschpa.org.
In support of the Executive Order, the Department of Energy and the Environmental Protection Agency released a new report Combined Heat and Power: A Clean Energy Solution that provides a foundation for national discussions on effective ways to achieve 40 GW of new, cost-effective CHP by 2020, and includes an overview of the key issues currently impacting CHP deployment and the factors that need to be considered by stakeholders involved in the dialogue.