Bladder Pump
Bladder Pump is a low-flow pneumatic device used for sampling applications. It consist of a flexible, squeezable bladder encased in a rigid outer casing and is available in variety of sizes, materials, and capabilities. It is used to monitor wells to minimize potential for cross contamination. Many low volume pump, submersible pump, and groundwater sampling pump models are available for bladder pump.
How does a Bladder Pump works?
Bladder pumps are lowered into a well's water column. Water enters the pump through the inlet in the upper, head section, via hydrostatic pressure, then flows down into the bladder and is passed through a check valve at the bottom of the pump. When the bladder is completely filled, the check valve closes so that there is no back flow. The water is then pumped up to the surface via injected gas pressure that squeezes the bladder. There is a pneumatic control box on the surface which usually regulates the gas pressure. Once the bladder is empty, the gas pressure is relaxed and the check valve opens again, restarting the process.
Applications of Bladder Pump:
It enables consistent high quality groundwater sampling in all types of applications.
It can pump to the surface quality samples from narrow and sometimes temporary wells as well as deep wells.
It offers excellent performance and reliable, consistent sampling even from low yield boreholes and liquids containing high solids, strong solvents or corrosive chemicals.
Pumping can also be carried out in non-vertical wells. It operates effectively at almost any angle and can be placed under landfills, tailings, storage.
Uses and Features of Bladder Pump:
Bladder pumps are EPA-accepted for low-flow sampling.
Bladders are generally constructed of relatively inert materials, and are nonporous.
When low-flow pumping rates are used, these pumps consistently collect high quality, uniform samples.
The bladder's design ensures that the injected gas does not come into contact with the sample.
It also keeps the sample from contacting any of the pump's moving parts which alleviates the danger of contamination from lubricants and fluids, such as oil or grease.
Although the bladder system will not be damaged if forced to run in a dry well, the bladder is susceptible to rapid pressure changes and freezing.
