A bubbler level gauge, also known as a bubbler system or bubbler tube level measurement system, is a type of hydrostatic level measurement device used to determine the liquid level in a tank or vessel. It operates based on the principle of hydrostatic pressure.

Here's how a bubbler level gauge works:

1. System Components:

   • A bubbler level gauge system typically consists of a bubbler tube, a pressure transmitter, and a control unit. The bubbler tube is a small-diameter pipe or tube installed vertically in the tank, with its open end submerged in the liquid.

2. Bubble Generation:

   • The bubbler system uses a gas (usually air or nitrogen) to generate bubbles inside the bubbler tube. The gas is supplied to the tube through a control valve and a supply line connected to the control unit.

3. Bubble Pressure Measurement:

   • The control unit regulates the flow of gas into the bubbler tube to maintain a constant pressure at the open end of the tube. As the gas escapes from the tube's open end, it creates bubbles that rise to the liquid's surface. The pressure inside the tube is adjusted to ensure that the bubbles reach the liquid surface without collapsing or being compressed.

4. Pressure Transmitter:

   • A pressure transmitter is installed at the top of the bubbler tube to measure the pressure of the gas inside the tube. The pressure transmitter converts the gas pressure into an electrical signal, which is proportional to the liquid level in the tank.

5. Level Calculation:

   • The electrical signal from the pressure transmitter is sent to the control unit, where it is processed to calculate the liquid level in the tank. The control unit typically includes a display or output signal that indicates the measured level.

6. Measurement Accuracy:

   • The accuracy of the bubbler level gauge depends on various factors, including the accuracy of the pressure transmitter, the stability of the gas supply pressure, and the calibration of the system. Bubbler systems are generally accurate and reliable for measuring liquid levels in tanks with relatively constant pressure conditions.

Bubbler level gauges are commonly used in industries such as water and wastewater treatment, chemical processing, oil and gas, and power generation. They are particularly suitable for measuring liquid levels in tanks or vessels with corrosive, abrasive, or hazardous fluids, where other level measurement methods may be impractical or unsafe.