Boiler feed Pumps are a special type of pump used to pump water into a steam boiler. Water can be a newly supplied or returned condensate produced by the condensation of steam produced by the boiler. These pumps are usually high-pressure units that draw from the condensate return system and can be centrifugal or positive displacement. Feedwater pumps range in size up to many kilowatts and the motor is typically separated from the pump body by some style of mechanical coupling. Large industrial condensate pumps may also serve as feedwater pumps.
In order to force the water into the boiler, the pump must definitely generate enough pressure to overcome the steam pressure developed by the boiler. This is typically achieved through the employment of a pump. Another common form of feed pump runs constantly and is given a minimum flow device to prevent over-pressuring the pump on low flows
In thermal power plants, the boiler feed pump is one of the key auxiliary machines that represent the guts of the system. The boiler feed pump has been improved and developed with the increasing capacity of thermal power plants, improvements to accommodate higher temperatures and pressures, and changes in operating methods. This white paper describes how the Boiler feed Pump has been scaled up to handle higher pressures.
BOILER FEED PUMP KEY SPECIFICATIONS
Typical Boiler feed Pump structures and materials for conventional supercritical and combined-cycle power plants. Shaft seal and bearing characteristics; technological development for higher capacity and performance. Actual development and provision of Boiler feed Pump with 100% capacity. Improved structural design to increase the stress tolerance of the Boiler feed Pump to accommodate the more stringent conditions of thermal power plant operation associated with renewable energy diffusion. An example of an effort to streamline Boiler feed Pump design to reduce manufacturing costs and save space.
In terms of capacity and pressure, the Boiler feed Pump has expanded and matured with the increase in thermal power generation facilities. Among the pumps used in thermal power plants, the Boiler feed Pump consumes the most energy because it has to generate the high pressure required by the boiler. This means that improving the efficiency of the Boiler feed Pump is an important issue that needs to be resolved to reduce its impact on the environment. The impeller used in the Boiler feed Pump is a centrifugal pump with a specific speed (Ns) of about 120 to 250 (m3 / min, m, min1).
In general, the higher the specific speed within this range, the higher the pump efficiency, and the same the specific speed, the higher the flow rate. Two Boiler feed Pumps, each with a capacity of 50%, are typically used as the main feed pump. If a Boiler feed Pump can provide 100% capacity, not only will it increase capacity to increase specific speed, but it will also improve efficiency by saving space and resources
In recent years, the introduction of renewable energy such as solar power and wind power has been progressing. Renewable energy does not use fossil fuels and does not emit carbon dioxide during power generation, so it is expected to continue to spread as one of the measures against global warming. However, since the output from solar power and wind power greatly depends on the weather conditions such as weather and wind, there is a disadvantage that it is difficult to operate an electric energy system using renewable energy in a stable manner.
To address this issue, thermal power plants need to provide increasingly flexible network operations with higher capacity to adapt to supply and demand. In particular, it is required to improve the load factor, minimize the minimum load factor, and shorten the startup time. In association with the supply-and-demand adjustment capability added to thermal power plants, Boiler feed Pumps must operate under more severe conditions such as increased frequency of start-ups and shutdowns, changes in feedwater temperature, and increased frequency of downhills. To meet these requirements, efforts have been made to improve the stress tolerance (toughness) of Boiler feed Pumps by examining the structure, materials, and design.
As described earlier, Boiler feed Pumps are the center of most piping systems in thermal power systems and are thus needed to supply high levels of practicality and reliability. On the other hand, it is also important to provide electricity at the lowest possible price, especially in developing countries, where demand for electricity is increasing and therefore the construction of many new thermal power plants is planned. For this reason, pump suppliers needed to get together to change the instrumentation for power generation plants and build efforts to cut back the prices for such equipment.
WORKING PRINCIPLE OF A BOILER FEED PUMP
A Boiler Feed Pump’s job is to pump condensate boiler feed water from the hot well to the boiler drum. The hot feed water is propelled outwardly radially across the walls of the pump as the shaft and impeller rotate, following the course of the flow. The fluid’s speed and pressure both rise as a result of this. The fluid is now accelerated and flung radially outwards towards the casing as it is directed to the next impeller blades along the flow path.
Such a progressive increase in flow rate and pressure; with each impeller, we ultimately reach the pump output pressure. The pump’s ultimate outlet pressure is higher than the boiler’s typical working pressure.
To create such high pressure, a multistage boiler feed pump has two or more impellers in sequence. The pressure created by each impeller is multiplied by the other impellers. The distance between each stage of the fluid route determines the pump’s total capacity.
While the pressure at each stage is mostly determined by the impeller size, the overall pressure is determined by the number of impellers in sequence. The temperature differential between the suction and discharge sides of the feed pump must be maintained as part of the feed pump’s operation. The feed pump in the feedwater system takes suction from the hot well via a strainer and discharges to the boiler via an orifice plate and feed check valve.
APPLICATION OF BOILER FEED PUMPS
Boiler Feed Pumps are used in a wide range of industrial plants and facilities. These pumps are a type of high-pressure centrifugal pump that comes in a variety of types and sizes and is utilized in a variety of plants, units, and manufacturing facilities.
Due to the high temperatures of the feed water, boiler feed water pumping applications often demand high pressures. At 212 degrees Fahrenheit and atmospheric pressure, water transforms into a gas. Boiler feedwater temperatures range from 225 to 250 degrees Fahrenheit, with some reaching 350 degrees Fahrenheit. As a result, the deaerator tank and pump input pipework frequently sustain pressures greater than the water vapor pressure to keep the feed water liquid.
Boiler Feed Pumps are built to withstand the amount of pressure required by your business. Boiler feedwater pumps use high pressure to transfer water into boilers. As a result, a boiler feed pump is designed to transfer feedwater into the boiler system at exceptionally high water pressure. A boiler feed pump can typically withstand pressures of up to 100 bar. In most circumstances, a certain amount of pressure is necessary for the operation of your boiler. It’s critical that the boiler feed pump you choose can meet that demand.
For applications such as boiler feed operations, sprinkling systems, washdown systems, filtration, and water treatment plant operations, a boiler feed pump can manage high-pressure needs. Pressures of up to 100 bar (1,500 psi) can be handled by a boiler feed pump. It can handle agricultural irrigation, desalination and reverse osmosis, pressure boosting systems, natural gas processing systems, and paper mill shower water, in addition to boiler feed applications.
Kiron Hydraulic Needs Private Limited, With the Brand name FTT Pumps is a renowned Boiler Feed Pump producer producing pumps to the most stringent technical criteria and the highest quality standards. Our dedication to quality extends beyond our products to encompass exceptional customer service, cutting-edge research and development, and continual improvement in all we do.