Membrane Sensors are very cost effecitive heat flux sensors. They are installed in the membrane of the furnace water wall. Membrane sensors only have two thermocouple embedded instead of four thermocouples for conventional tube heat flux sensors. Since membrane sensors are installed on the membrane rather than in the waterwall tube, they are less effective for the thermal impact measurement caused by water jet. Membrane sensors are the best candidate for wall blower and water lance operation optimization. They can also be used to installed with the water cannon system to provide better resolution of heat flux.

Membrane sensors have many other advantages such as:

• Low capital cost (half price of conventional type)
• Easy installation and replacement, very low installation cost
• Can be installed when boiler is online
• Same data acquisition interface as tube heat flux sensors
• Accurate heat flux reading

The mounting of membrane sensors takes place in 5 easy steps:

1. determining the sensor position
2. (optional) machining the mounting block
3. welding the mounting block
4. drilling
5. putting the sensor in position.

All these actions can in principle take place with the boiler in operation.