The range of sensors are available with different controllers giving you the same great performance with different communication, display, and control options. With the Pi range of controllers, you get everything that you need – and nothing that you don’t, without sacrificing the quality of measurement. Each sensor comes with a ‘clean me’ alert and can be run with a constant head weir or a flow meter, to maintain a constant flow.
As particles in a water stream pass through a measurement cell they break a laser beam inside the particle counter. This break is measured by a detector opposite the laser beam and the number of breaks is equal to the number of particles and the size of signal (created as the particle passes through the beam) is proportional to the size of the particle. The Pi instruments are unique in the marketplace in that they allow:
The most common application for a Pi particle counter is in water treatment and the optimization or ongoing monitoring of filter effluent.
The CounterSense can be coupled with turbidity and differential pressure sensors and offers on-board PID control of automatic backwash and can provide data logging and optional remote access via the mobile phone network such that you can have your filtration expert in your plant wherever they are in the world. The CounterSense is possibly the most advanced online particle analyzer in the world.
The FilterSense is designed for multi-point monitoring of filter banks, lowering the cost per point with up to 15 particle analyzer sensors.
Other applications for Pi particle counters include:
Across the developed world failures in coagulation and filtration have led to outbreaks of Cryptosporidiosis and other illnesses caused by organisms such as Cryptosporidia and Giardia.
Continuous monitoring of the turbidity at the outlet of a filter is essential and even a legal requirement in some countries. Turbidity is a good measure of the clarity of the water and gives a single, understandable output for operators and is most sensitive to smaller particles (particles <1µm in size).
Particle Counters look at larger particles (usually larger than 2µm) and provide additional information over and above that provided by turbidity meters, particularly information regarding the break down of a filter and the passing of Crypto sized particles, often undetectable by a turbidity meter.
In the past many water companies, water authorities, local county councils, etc. have put turbidity meters on filters but not particle counters, largely due to the higher cost of particle counters.
Improvements in water treatment have greatly reduced the risk posed by possible Cryptosporidia outbreaks following well published outbreaks around the world in the 1990s and later. As part of these improvements most filters have been fitted with turbidity meters that are great at picking up coagulation failures. In some regions filter banks have also been fitted with Particle Counters as they have proven to be better at picking up the initial stages of filter breakthrough or ‘channeling’ (where the water meter finds a way through the filter media without being filtered).
Using Turbidity Meters AND Particle Counters on the outlet of a filter not only provides an indication when there are more small particles (turbidity) but also when the larger Cryptosporidia size particles are coming through (particle counter).
Improvements in technology now means that a filter bank can be fitted with particle counters for a similar price to turbidity.
In most Cryptosporidium outbreaks there has been a failure of both coagulation and filtration. If coagulation fails then un-coagulated particles can pass straight through a filter. A turbidity meter would pick this up and show the operator that there was something wrong.
If, however, the filter starts to pass large, Crypto sized particles, or to break down, or to ‘channel’ (a channel opens in the filter from top to bottom) it is unlikely that this will be picked up by a turbidity meter, but can clearly be seen with a particle counter.
In the past, to install a bank of 8 filters with a particle counter would have meant a capital cost of approximately $45,000 which has been a stumbling block for many. Now Pi has made a multipoint analyzer providing the same functionality for approximately $25,000 taking away much of the price objection.
Turbidity Meters are more sensitive to smaller particles which are present if coagulation fails.
Particle Counters are more sensitive to filtration failures.
So which do you need?
You need both.
Why not contact us and see what we may be able to do to help you reduce your risk of a Cryptosporidia outbreak.
In addition to the features common to both listed above, the CounterSense and FilterSense particle size analyzers have the following additional features.
As well as the recent 20th Anniversary Party, Pi are celebrating 20 years of working with US company, Chemtrac Inc.. Chemtrac Partnership Essential to Pi
Ringhals Nuclear Power station in Sweden is the most recent in a long list of power stations to benefit from Pi’s experience with particle counters.
LEADING instrumentation company, Process Instruments is using particle counters to optimise filter backwashes, reducing the frequency, increasing the quality of the water and saving thousands
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