1 Pro Minent Metering Pumps and Pump Systems

1 Pro. Minent® Metering Pumps and Pump Systems

METERING PUMP DEFINITION Convey Measure Adjust 2 Pro. Minent® • Convey (like any pump) • Measure (repeated displacement of defined volume) • Adjust – Volume per displacement – Frequency of displacements

METERING PHILOSOPHY • Think of the pump as a continuous fluid measurement device 3 Pro. Minent® • Converts batch processes (fluid measured, then mixed), to in-line processes (fluids continuously measured and mixed)

What is a Metering Pump? Hydraulic Institute Definition: Some Pump Manufacturers Add: “It includes a mechanism for varying the effective frequency of displacements. ” 4 Pro. Minent Fluid Controls Pro. Minent® “A controlled volume pump (also called a “metering”, “proportioning” or “chemical injection pump”) is a reciprocating power pump used to accurately displace a predetermined volume of liquid in a specified time period and is driven by power from an outside source applied to the pump mechanism. It includes a mechanism for varying the effective plunger, piston or diaphragm displacement. ”

What claims to be a Metering Pump, but isn’t? Gear Pump Displacement per revolution not adjustable. Not linear from high to low RPMs due to slip at low speed. Air Operated Diaphragm Pump Displacement per stroke not adjustable. Not repeatable due to variable air pressure, flexible diaphragm. Peristaltic Pump Displacement per revolution not adjustable. Chemical incompatibility common w/ rotor. Displacement per revolution not adjustable. Tube stretch prevents repeatability. 5 Pro. Minent Fluid Controls Pro. Minent® Progressing Cavity Pump

6 Pro. Minent® What’s all This?

Metering Pump System Hydraulics and Application of Accessories The metering pump system design, the fluid pumped, and the accessories installed all play a vital role in system safety, repeatability and reliability. 7 Pro. Minent Fluid Controls Pro. Minent® Key Concept: Metering Pump System

Suction Head Positive Suction Head (flooded suction) 8 Pro. Minent Fluid Controls Pro. Minent® Negative Suction Head (suction lift)

Suction Lift Atmospheric pressure always pushes down on any fluid surface. When the pump diaphragm creates a negative pressure in the pump head, atmospheric pressure forces fluid up the suction tube to fill the cavity. If the pump pulled a perfect vacuum, the maximum suction lift possible on earth, pumping water, is 34 feet. 9 Pro. Minent Fluid Controls Pro. Minent® 14. 5 psia Atmospheric pressure at 500 feet above sea level = 14. 5 psia = 1 bar = 34 feet of water

Suction Lift What happens if the tank is not vented (open to atmosphere)? 14. 5 psia 10 Pro. Minent Fluid Controls Pro. Minent® 14. 5 psia

Specific Gravity Sulfuric acid density = 15. 34 lbs/gal Therefore: Water density = 8. 34 lbs/gal S. G. = 1. 84 Ammonia density = 5. 25 lbs/gal Therefore Water density = 8. 34 lbs/gal S. G. = 0. 63 Because atmospheric pressure forces fluid into the pump head during the suction stroke, if the fluid has a specific gravity greater than 1. 0, the suction lift ability will be reduced. Specific gravity is independent of viscosity, and does not impact pump capacity, only suction lift capability. 11 Pro. Minent® Specific Gravity is the fluid’s density in relation to the density of water (S. G. 1. 0). For example:

Specific Gravity Impact on Suction Lift Actual Suction Lift = Rated Suction Lift (water) / S. G. Rated Suction Lift for VAMb 04120 = 6. 6 feet Actual Suction Lift = 6. 6 / 1. 4 = 4. 7’ 12 Pro. Minent Fluid Controls Pro. Minent® Application: Chromic Acid (1. 4 SG)

Viscosity is a measure of a fluid’s resistance to flow. Viscosities greater than that of water increase friction loss and result in reduced pump capacity. When selecting a pump for viscous fluids: Oversize the pump Put springs in the valves to help seat the balls Reduce stroking rate to minimum possible Keep stroke length as great as possible Provide flooded suction with oversized suction line 13 Pro. Minent Fluid Controls Pro. Minent® Use high viscosity solenoid pumps

Fluid S. G. Viscosity (SSU) Ammonia SAE 30 oil Brine Gasoline Glycerine Nitric Acid Sulfuric Acid Water 0. 63 0. 9 1. 2 0. 73 1. 26 1. 42 1. 84 1. 00 29. 5 200 @ 130 deg F 33 30 2950 31. 5 66 31. 5 14 Pro. Minent Fluid Controls Pro. Minent® Specific Gravity and Viscosity of Common Fluids

Vapor Pressure Matter exist as solids, liquids or gasses. The state of matter depends on the compound itself, the pressure around it, and the temperature. The Vapor Pressure of any fluid relates to the pressure and temperature at which it flashes from a liquid phase to a gas phase. It is defined as the pressure exerted when a liquid is in equilibrium with its own vapor. 15 Pro. Minent® The higher the vapor pressure, the more likely the fluid will vaporize on the suction side of a pump during the suction stroke, causing cavitation.

Pressure Relief Valve Prevents over-pressurizing pump and piping system. Pressure Adjusting Nut Spring Diaphragm Hub 16 Pro. Minent® Diaphragm

Pressure Relief Options - Flooded Suction 3 -port PRV 2 -Port BPV on Tee 17 Pro. Minent® Pressure Relief may discharge back to tank, but where tank is distant from pump, relief back to suction line is common.

Pressure Relief Options - Suction Lift Two port back-pressure valve off of a tee on the discharge line 18 Pro. Minent® Three port in-line pressure relief valve discharges to tank through relief port

Backpressure Valve Provides backpressure to improve repeatability. Prevents siphoning when suction head exceeds discharge head. Pressure Adjusting Nut Spring Diaphragm Hub 19 Pro. Minent® Diaphragm

Backpressure Valve The anti-siphon (backpressure) valve prevents the vacuum from causing chemical to be drawn into water line. 20 Pro. Minent® The injection quill can create a venturi effect in a flowing pipe, developing a vacuum. This can draw chemical through the system even if the pump is stopped.

Backpressure Valve 21 Pro. Minent® The backpressure valve also prevents fluid from simply free-flowing through the system when the suction port is higher than the point of discharge.

Backpressure Valve When discharging into a vacuum line, use two backpressure valves to ensure maximum protection against siphoning. The backpressure created by the two valves (and the injection valve) is not additive. Whichever valve is set at the highest pressure will determine the system pressure at the pump. 22 Pro. Minent® Regulatory agencies may require use of two anti-siphon valves in certain applications such as adding fluoride to drinking water.

In a reciprocating pump system, the entire fluid column between the pump and injection point stops flowing at each suction stroke and is forced to flow at each discharge stroke. Overcoming inertia creates large momentary pressure spikes on the pump system. 23 Pro. Minent® Pulsation Dampener

Pulsation Dampener AIR A pulsation dampener minimizes the pressure spikes by using compressed air to absorb the forces due to momentum of the fluid inertia. The flow losses are called acceleration/deceleration forces. 24 Pro. Minent® FLUID

Pulsation Dampener Principle of Operation: Air is compressible, fluid is not. Charge dampener air pressure to 90% of fluid pressure. You must have backpressure for dampener to be effective. Locate dampener as close to pump as possible, preferably as shown. 25 Pro. Minent® Size dampener volume to 26 times fluid displacement per stroke, or consult piping program.

Suction Lift vs. Flooded Suction Lift Flooded Suction Actual lift = Rated lift (water)/ Specific Gravity Minimizes cavitation and off-gassing problems. Requires foot valve/strainer Best for viscous fluids. Required for selfdegassing pumps and degassing bleed valves. Short suction line best. Line should always be sloping upwards. Diaphragm failure can drain tank. 26 Pro. Minent® Short suction line best. Line should always be sloping upwards. Requires isolating valve.

Suction Side Pulsation Dampening 27 Pro. Minent® Where losses in suction line cause cavitation, a suction side pulsation dampener may be required. The air side of the dampener should be at atmospheric pressure (not charged).

Foot Valve Suction Tube Fitting Check Ball Check Seat 30 mesh screen keeps solids out Ceramic weight keeps suction line straight, ports let fluid in. 28 Pro. Minent® The foot valve is used in a suction lift application to prevent loss of prime when the pump is stopped, and to improve repeatability by preventing cavitation.

Injection Valve Injection quill puts chemical into flow for good mixing NPT thread to mount into pipe Valve Spring (not used in PTFE valves) provides backpressure, ensures ball seating. Ball Check Seat Tube Fitting Discharge Tubing from Pump 29 Pro. Minent® Check Ball

Real pic of cal column Calibration Column • Provide a verification of the flow rate of the chemical feed pump • Available in borosilicate glass or PVC • Sizes from 100 m. L to 10000 m. L • Marked in gallons or milliliters 30 Pro. Minent® noelt:

Multifunction Valve • Operated by smooth-action rotary knobs which automatically return to their initial position when released • Mounted directly on the liquid end of the pump for: Backpressure Antisiphon Priming Draining the discharge line 31 Pro. Minent® Pressure relief

Float Switch • Monitors the fluid level in the chemical tank • Single stage function ä Minimum level indication with simultaneous shut down of the pump Two stage function ä First stage early warning annunciation ä Second stage will shut down the pump after an additional drop in the fluid level 32 Pro. Minent® •

Flow Monitor 33 Pro. Minent® The metering monitor is used to monitor the volume per pump stroke by using a plastic encapsulated metal float that is detected by the adjustable proximity sensor. Adjustable from 1 -125 strokes. Plugs into front of pump.

noelt: Typical Accessory Installation Suction Lift Injection Valve prevents backflow from pipe Backpressure/Antisiphon valve provides backpressure for repeatability, prevents siphoning Pressure gauge allows setting valve pressures Pulsation dampener reduces head loss, pulsation Pressure relief valve protects system components Foot valve/strainer prevents loss of prime, plugging by solids 34 Pro. Minent® Ken to find different graphic

Piping Simulation • Used for motor driven pumps only • Shows if you need accessories • Application will run well 35 Pro. Minent® • Solves problems BEFORE they happen

• Pump type • Information from the technical data in the catalog • Chemical being metered • Suction lift • Chemical tank pressure • Size and length of suction and discharge lines • Number of valves and fittings in the lines • Back-pressure • Discharge head 36 Pro. Minent® Information Necessary

37 Pro. Minent® Any Questions?