Envco – Environmental Equipment

This instrument brings precise measurements to the process. The measurement arm is mounted to the filter safety railing with a non-marring clamp. A pulley at the tip of the arm allows easy deployment and retrieval of the sensor probe. The sensor drop point can extend out to 3 feet over the filter from the rail and can easily be moved to other locations within the same filter to check for dead spots or uneven expansion.

Prior to the backwash cycle, the infrared sensor probe is lowered to rest on the top of the media with sensor cable taught. The sliding ruler on the measurement arm is moved to the “zero” position.

Backwash begins with turbidity flushed out to wastewater trough. Sensor probe remains fully engaged in expanding media. After turbidity has been evacuated, sensor probe is raised to just above fluidized media. All LED’s on meter will go out at this point. Upon completion of the backwash cycle, the media will settle to a level slightly lower than the pre-backwash level. The scale marker on the measurement arm will be on the negative side of the original “zero“ position.

Portable and lightweight, the measurement arm provides a sturdy base for precision measurements of expanding filter beds using the Raven Sludge Interface Detector model SID-10200.

MEASUREMENT SEQUENCE
1. Pre-Backwash – lower sensor probe to rest on top of filter bed and slide ruler to zero.
2. Start Backwash – sensor fully engaged in turbidity and debris with all 20 red LED’s illuminated.
3. Clarified Backwash – sensor raised just above expanding filter bed. Repeat until maximum expansion. Note marker on ruler to determine expansion in inches.
4. Post Backwash – return sensor to rest on top of settled filter bed. Note marker on ruler to compare depth of post backwash settled media to pre-backwash level. Ruler marked to negative three inches below “zero” baseline.

The sensor drop point can extend out to three feet into the filter chamber. The operator can range the lowered sensor over nine linear feet of expanding filter bed to check uniformity of expansion from one location.

INTERFACE DETECTOR
Analyzing the dynamics of the expansion from within the media bed, the infrared sensor probe reports to the operator via the interface detector mounted on the Expansion Measurement Arm.

Operation of the interface detector is simple. No need to calibrate the sensor. It automatically references changes in density. A sensitivity knob fine tunes the probe. Measure the “ragged edge” on top of the expanded bed by adjusting sensitivity to “high” to determine if the top of the bed has a gradual or well defined interface. How do you interpret a gradual uneven interface over several vertical inches between the expanded bed and the wash water above?

A pivot point connection on the measurement arm allows the operator to range the probe over 9 linear feet of expanding media in a semi-circle to verify uniformity of expansion at multiple points.

Infrared sensors are uniquely suited to give more than just up or down information about the dynamics of the media bed during backwash. It’s the only technology that lets you interact with the event in so many ways.

Ordering Information
SID-10500-20 Interface Detector with Filter Media Probe 20ft cable
SID-10500-30 Interface Detector with Filter Media Probe 30ft cable
SID-10500-40 Interface Detector with Filter Media Probe 40ft cable

Replacement Parts
SID-10503-20 Replacement Media Probe 20ft cable
SID-10503-30 Replacement Media Probe 30ft cable
SID-10503-40 Replacement Media Probe 40ft cable