Waste Heat Boiler

The waste heat boiler is made of a steam drum and a large membrane wall cavity. The high-temperature flue gas enters the boiler membrane wall cavity from the top. The flue gas is cooled from about 1100 degrees at the inlet to about 550 degrees at the outlet. A vertical membrane wall cavity is used. The high-temperature flue gas flow rate is reduced, allowing more dust to settle at the bottom of the large cavity of the membrane wall, which is beneficial to the natural settlement of mineral dust and prevents furnace tube wear. The boiler feed water enters the steam drum and is distributed to the lower header of the large cavity of the membrane wall through the downcomer. It is heated by the flue gas to form a steam-water mixture and enters the upper header. After entering the steam drum through the riser pipe, the steam and water are separated and then discharged.

Here's a general overview of how a waste heat boiler works:

Waste Heat Source: Waste heat boilers are typically used in industrial settings where there are high-temperature waste gases or fluids generated as a byproduct of a process. These waste heat sources can include exhaust gases from combustion processes, flue gases from furnaces or kilns, hot gases from chemical reactions, or hot process fluids.

Heat Transfer: The waste heat is transferred from the waste gases or fluids to the working fluid, typically water or steam, in the waste heat boiler. This heat transfer can occur through various methods, such as convection, conduction, or radiation, depending on the specific design of the boiler.

Boiler Operation: The working fluid absorbs the heat energy from the waste gases or fluids, resulting in an increase in temperature and pressure. The waste heat boiler is designed to handle the high temperatures and pressures associated with the waste heat source.

Steam or Hot Water Generation: The high-temperature working fluid in the waste heat boiler is used to generate steam or hot water. This steam or hot water can be utilized for various purposes within the industrial process, such as heating, power generation, or other heat-intensive operations.

Additional Heat Recovery: In some cases, multiple waste heat boilers can be used in series to recover heat at different temperature levels. This allows for more efficient utilization of the waste heat and maximizes the overall energy recovery from the industrial process.

Waste heat boilers are designed to be highly efficient in capturing and utilizing waste heat, thereby improving energy efficiency and reducing the environmental impact of industrial operations. They are commonly used in industries such as power generation, petroleum refining, chemical production, steel manufacturing, and cement production, where significant amounts of waste heat are generated.

It's important to note that the design and configuration of waste heat boilers vary depending on the specific waste heat source, temperature, pressure, and other process parameters. The boilers must be carefully engineered to ensure safe and reliable operation, considering factors such as corrosion resistance, thermal stress, and the control of emissions.