MOYNO (PROGRESSING CAVITY): These pumps are sort of amazing in some regards and just plain overkill in others. They are progressive cavity but really shouldn’t be asked to pump dry to build a prime — they should be treated like a centrifugal in ensuring that prime is established to the pump head before running. What makes these pumps amazing is that when they have prime, they’ll pump something to the moon if you ask them to. On the other side of that coin, you need to ensure really good pressure relief and safeties. Overall, they’re sort of overkill for the standard micro-distillery unless you’re doing something that requires very high and constant pressures, like pumping something forward through a filter bank, pushing stillage and sludge long distances to waste water treatment, etc.
PERISTALTIC: These pumps are small duty pumps, usually dosing pumps for chemicals, with flow rates in the gallons per day or gallons per week ranges. If you have one of these, it’s probably on your water quality system, CIP dosing system, or boiler chemical feed system. Peristaltic pumps are positive displacement and are usually made from a small section of tubing with a rotating shoe that compresses the tube as it travels in a circle. These pumps are great for pumping very low flow rates, build prime easily, and are generally started automatically by a controller and run to a certain dosing rate.
AIR OPERATED DIAPHRAGM PUMPS: If you want to run an intrinsically safe pump, from an electrical standpoint, these pumps are the cat’s meow. AODs use compressed air to flex two opposing diaphragms to create flow. These pumps are positive displacement, can build prime, and because they don’t use a directly attached motor you don’t have to worry about XP electrical classifications. Speed control is established by regulating the amount of air to the pump more air, more flow. Most AODs will produce a “surge” flow, meaning that like a beating heart, every cycle of the diaphragms will deliver a constant but up-and-down flow rate. Great for transferring between tanks, running something through a filter bank, etc, but not great for feeding something that requires constant even flow, like a continuous column. So what happened with P-502? Check out the link to get a good idea how these pumps
Published on Sep 19, 2017