The global power generation industry is rapidly changing. Increases in power consumption, economic growth and environmental pressures are creating significant opportunities for safe and reliable plant operation.
Power Plant Efficiency Opportunities
Level control applications in power plants lend themselves to performance improvements that can enhance a plant’s overall safety, efficiency or profitability. Technologies offering more precise level indication that are not affected by process variables provide operators with the ability to better manage overall power plant performance. For example, feedwater heaters in coal-fired plants historically suffer from inefficiencies due to poor level controls, which increase heat rate, thus reducing efficiency. The illustration below indicates some of the most common level control applications in the power generation industry.
Liquid Level Applications
- Fuel Oil Storage: Crude oils with lower flash points represent a greater fire hazard and require safety-certified liquid level switches and transmitters.
- Open Atmosphere Sumps: Level control in collection and processing basins must often tolerate corrosive media, punishing weather conditions and liquids with high solids content.
- Condensate Storage: Accurate, reliable liquid level monitoring in the condensate storage tank ensures the proper supply of make-up water.
- Deaerator: Pressure fluctuations are extensive in the deaerator and result in flashing, thereby requiring level controls that can withstand varying temperatures and pressures.
- Condensate Drip Legs & Drains: Level instrumentation must contend with high temperatures and pressures associated with drip legs, to ensure proper functioning of the condensate collection system and prevent damage to the turbine.
- Steam Drums: Precise level in the steam drum is important to optimize steam/water separation and steam quality.
- Condenser Hotwell: Level control in the hotwell can prevent make-up water loss in the turbine cycle due to leakage, steam venting or other usage.
- Feedwater Heaters: Feedwater heater level is controlled to prevent damage to expensive hardware, while at the same time optimizing level control to improve efficiency (heat rate) during base load, as well as load following operations.
- Boiler Blowdown Tank: Good boiler blowdown practices reduce water treatment needs and operation costs, as well as the chance of catastrophic explosion.
- Lubrication Oil Tanks: Reliable level monitoring of lube oil reservoirs ensures proper functioning of turbines, electrical generators and other equipment with integral lubrication systems.
- Ammonia/Caustic/Acid Storage: Managing hazardous and non-hazardous chemical storage inventory and replenishment safely and reliably is critical to ensure availability during normal operation.
- Cooling Tower Basin: Proper level control in the cooling tower basin eliminates low-level damage to pumps, while preventing costly overflow conditions. Vulnerability to foam from chemical injection and modest buildup considerations are fundamental to selecting the correct level technology.
Liquid Level Control Solutions
Magnetrol offers the power generation industry one of the most complete lines of liquid level control technology solutions, as well as extensive power plant efficiency applications experience for challenging process control environments.
- Series 75 Sealed External Cage Liquid Level Switch: Self-contained units designed for side mounting to a tank or vessel with threaded, socket weld or flanged pipe connections.
- Series B40 High-Pressure/High-Temperature Liquid Level Switch: Specifically designed for HPHT service conditions such as boilers, available in rugged industrial or ASME B31.1 construction.
- Tuffy® II Side-Mounted Float Switch: Compact-sized, float-actuated device for horizontal mounting in a tank or vessel through threaded or flanged pipe connections.
- Digital E3 Modulevel® Displacer Transmitter: Advanced, intrinsically safe two-wire instrument utilized buoyancy principle to detect and convert liquid level changes into a stable output signal.
- Displacer Type Liquid Level Switch: Offering a wide choice of alarm and control configurations, these units are well suited to simple or complex applications, including foaming or surging liquids and agitated fluids, and typically cost less than other level switch technologies.
- Eclipse® Model 706 Guided Wave Radar Transmitter: Loop-powered, 24 VDC device utilizes diode-switching technology for outstanding signal strength, and offered with a comprehensive probe offering for a wide variety of applications.
- Pulsar® Model RX5 Pulse Burst Radar Transmitter: The latest generation of non-contact radar transmitters offers lower power consumption, faster response time and ease of use, compared to most loop-powered radar transmitters.
- Model R82 Pulse Burst Radar Transmitter: An economical, loop-powered, non-contact radar transmitter that brings radar performance to everyday applications.
- Magnetic Level Indicators: AtlasTM and Aurora® magnetic level indicators offer reliable visual indicator solutions, with or without accompanying continuous level transmitters.
- Jupiter® Magnetostrictive Transmitter: High accuracy and high linearity at a reasonable price.