Application of Tuning Fork Liquid Level Switches in Slurry Measurement of Desulfurization Tower

To control start-stop of the pump, tuning fork liquid level switches are crucial to detect the fluctuating slurry level in desulfurization absorption tower, and to report the alarm signals.

Compared with peers, Ring-11 (Tuning Fork) Liquid Level Switches has the following characteristics and advantages:

●　With only 40mm fork length, specially designed for pipelines and other applications with constricted space.

●　High sensitivity due to the precisely pre-adjusted harmonic resonant frequency of fork, the lowest measurable medium density can be as low as 0.5g/cm³.

●　With strong disturbance resistance ability, not influenced by foam, bubbles, viscosity, vibration and other liquid characteristics.

●　Four optional outputs: relay, two-wire system, NAMUR and transistor.

●　Passed SIL2 / SIL3 Functional Safety Assessment, as well as certified for both Intrinsic Safety and Flameproof Enclosure explosion protection.

Depends on the operative condition, Ring-11 Liquid Level Switches can be installed either horizontally, vertically or obliquely. However, because the mainstream process of desulfurization is based on limestone method, the mainstream tower type is spray scrubber, with 5 ~ 6 pH value at the bottom slurry, and reaches 6 ~ 8.5 after mixing desulfurizer. Under low pH value and high temperature (within 250 ℃), reliable instrument are putting forward in such strong corrosivity and harsh working conditions.

Other than that, following tips need to be pay attention with:

1. To prevent the instrument from filling impact damage or generating false signals, avoid installing instrument near inlet and outlet.

2. Please make sure the gap between fork bodies has same direction as medium flow. Surface of fork should be parallel to the movement direction of measured medium. To avoid measurement error caused by medium resistance or reduce buildup on the fork, tuning fork should be mounted in such a way that the surfaces of the blades are parallel to the product movement.

3. For viscous medium, install the instrument vertically to avoid medium hanging or build-up.

4. In case hanging of viscous slurry, the tines (fork body) shall be cleaned regularly. It is recommended to install a cleaning device to automatically clean the tines.

5. To improve efficiency, when measuring the viscous slurry with large amount of impurities, it is not recommended to select contact liquid level switch in low liquid level.