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Externally Fired Boiler

An externally fired boiler is a type of steam boiler where the combustion of fuel takes place outside of the boiler shell. In this type of boiler, the furnace or firebox is located outside the boiler shell, and the hot gases produced by the combustion of fuel are then passed through tubes or flues that are immersed in water inside the boiler shell. The external firing of the boiler provides several advantages over internal firing, such as the ability to use a wide range of solid, liquid, or gaseous fuels, improved combustion efficiency, and easier maintenance of the combustion system. However, the design of an externally fired boiler is more complex and requires additional components such as an external furnace, fuel supply system, and a system for delivering the hot gases to the boiler tubes. Externally fired boilers are commonly used in industrial processes where the quality of steam or the characteristics of the fuel require the use of this type of boiler. They can be found in applications such as power generation, chemical processing, and food processing. Externally fired boilers are used in various applications within the food industry. One of the main applications is in the production of certain food products that require high-temperature steam for cooking, sterilization, or drying. For example, in the production of canned foods, steam is used to sterilize the product and to create a vacuum seal to prevent spoilage. Another common application of externally fired boilers in the food industry is in the production of beverages such as beer and distilled spirits. The boiling of the wort during the beer brewing process requires precise temperature control, which is provided by steam generated in an externally fired boiler. In the distillation of spirits, steam is used to heat the mash and to vaporize the alcohol, which is then condensed and collected. Externally fired boilers can also be used in the food processing industry for heating water or other process fluids that are used in the production process. This can include heating water for cleaning and sanitation, or heating oils and other ingredients for mixing or blending. Externally fired boilers are an important tool in the food industry, providing high-temperature steam for cooking, sterilization, and drying, as well as for heating water and other process fluids. The working principle of an externally fired boiler involves the combustion of fuel outside the boiler shell and the transfer of heat to the water inside the boiler shell. Here are the basic steps in the process: • Fuel is burned in an external furnace or firebox, creating hot gases that flow through flues or tubes immersed in the water inside the boiler shell. • As the hot gases pass through the tubes or flues, they transfer heat to the water, causing it to boil and generate steam. • The steam is then collected in the steam space at the top of the boiler and used for various industrial processes, such as powering turbines or heating processes. • The hot gases, after transferring heat to the water, exit the boiler and are vented to the atmosphere through a chimney or stack. Externally fired boilers can use a variety of fuels, including solid fuels such as wood, coal, or biomass, as well as liquid fuels such as oil and gas. The design of the external furnace and the arrangement of the tubes or flues can vary depending on the fuel being used and the requirements of the specific application. The working principle of an externally fired boiler is based on the transfer of heat from the combustion of fuel to the water inside the boiler shell, allowing for the generation of steam that can be used for industrial processes. There are several manufacturers of externally fired boilers, each with their own unique designs and product offerings. Here are some key manufacturers of externally fired boilers: 1) Thermax Limited - Thermax is a global company that specializes in energy and environment solutions, and offers a range of externally fired boilers for industrial applications. 2) Babcock and Wilcox - Babcock and Wilcox is a leading supplier of power generation equipment, including externally fired boilers for a variety of industries. 3) Cochran - Cochran is a UK-based company that specializes in the design and manufacture of industrial boilers, including externally fired boilers for a range of applications. 4) Clayton Industries - Clayton Industries is a manufacturer of steam generators and boilers, including externally fired models for industrial processes. 5) Forbes Marshall - Forbes Marshall is an Indian company that offers a range of steam and energy solutions, including externally fired boilers for the food and beverage industry. 6) Rentech Boiler Systems - Rentech is a US-based company that offers a range of externally fired boilers for power generation and industrial applications. These are just a few examples of the many manufacturers of externally fired boilers. When choosing a boiler, it's important to consider factors such as fuel type, operating pressure and temperature, and specific application requirements.