Geotech 1.66x18, Инструкция по установке и эксплуатации

Страница: 6 / 36

4
Section 1: System Description
Function and Theory
The PFAS Free Portable Bladder Pump is designed specifically for sampling per- and
polyfluoroalkyl substances (PFAS) such as perfluorooctanoic acid (PFOA) and
perfluorooctane sulfonate (PFOS) in groundwater. PFAS compounds are synthetic
chemicals used in firefighting foams, stain resistant carpets, and other repellant/non-stick
applications. A chemically stable substance with low volatility, PFAS compounds are not
absorbed well in soil and can migrate to water sources. The PFAS Free Portable Bladder
pump is made with PFAS free materials such as 316 Stainless Steel, high-density
polyethylene (HDPE), and Buna-Nitrile to provide representative water samples for
testing.
The PFAS Free Portable Bladder Pump is proven to not contribute any PFAS substances
to samples. Complete pump, tubing and safety cable have been soak tested and
laboratory analyzed under ‘EPA 537 Modified’ method. The samples from those tests
showed non-detect for all 25 PFAS analytes.
(See Section 6: System Specifications)
The pump is ideal for both gentle low-flow sampling and higher flow rate purging. Timed
ON/OFF cycles of compressed air alternately squeeze the flexible bladder to displace
water out of the pump to the surface and then exhaust the air allowing the pump to refill.
Fluid enters the pump through the fluid inlet check valve at the bottom of the pump body
via hydrostatic pressure. The bladder then fills with fluid. Compressed air enters the space
between the bladder and the interior of the pump housing. The intake check valve
(bottom) closes and the discharge check valve (top) opens. Compressed air squeezes the
bladder, pushing the fluid to the surface (see Figure 1-1). The discharge check valve
prevents back flow from the discharge tubing. Operated by the Bladder Pump Controller
(BP Controller) or Geocontrol PRO, this cycle automatically repeats.
Compressed air does not contact the sample. The bladder prevents contact between the
pump drive air and the fluid sample.
Figure 1-1: Bladder Pump Operation