Chapter 23

Steam Boilers

Operation and Maintenance

Brewery boilers generally operate under high temperatures and pressures. Given that they are subject to extreme working conditions, it is important to ensure that they are properly maintained—not only for reliability and efficiency purposes but for safety as well.

Keep the Boiler Clean

Any residue, such as soot or scale, that coats the heat transfer surfaces of the boiler will reduce its efficiency and also increase the likelihood of equipment failure. Cleaning this surface according to manufacturer’s recommendations is important to maintaining optimum boiler performance and equipment life. Residue that coats the tubes of a boiler will interfere with heat transfer and elevate the flue gas temperature.

Perform Regular Blowdowns

Water, especially hard water—the name given to water that contains high concentrations of calcium and magnesium—usually contains dissolved minerals. In a boiler, minerals in the water—especially chloride, iron, calcium, magnesium, and alkaline ions—can build up as scale on the boiler’s inner surfaces. This whitish buildup can reduce boiler efficiency—heat transfer, block water flow, and increase wear and tear.

Boiler Water Treatment

Treatment is crucial for steam boilers as it will extend the life of the boiler and piping. It will also maintain the efficiency of the system. If the steam system loses water and has to make up fresh water, this new water will have solids that will adhere to the boiler heating surfaces causing scale, reducing the heat transfer ability. In addition, the fresh water will have oxygen which will pit the inside of the boiler and piping.

Check Steam Traps

In a boiler, since the insulation around steam lines is not 100 percent effective, it’s common for some steam to condense. The boiler system must have a way to separate the condensate from the steam to maintain pressure and keep the steam flowing down the line. Steam traps accomplish that separation.

Keep a Maintenance Log

Pressure, water temperature, and flue gas temperatures should be recorded daily, as they can serve as a baseline reference for system operation and troubleshooting problems. More detailed inspections and checks should be performed to document system performance, which can be very important since a gradual change in system operating conditions over time may not be readily apparent without the use of such documentation.

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