air lift mud pump pricelist

If you are supplying pump supplies, you can find the most favorable prices at Alibaba.com. Whether you will be working with piston type or diaphragm type systems, reciprocating or centrifugal, Alibaba.com has everything you need. You can also shop for different sizes air lift pump wholesale for your metering applications. If you operate a construction site, then you could need to find some concrete pump solutions that you can find at affordable rates at Alibaba.com. Visit the platform and browse through the collection of submersible and inline pump system, among other replaceable models.

A air lift pump comes in different makes and sizes, and you buy the tool depending on the application. The pump used by a filling station is not the one you use to fill up your tanks. There are high flow rate low pressure systems used to transfer fluids axially. On the other hand, you can go with radial ones dealing with a low flow rate and high-pressure fluid. The mixed flow pump variety combines radial and axial transfer mechanisms and works with medium flow and pressure fluids. Depending on what it will be pumping, you can then choose the air lift pump of choice from the collection at Alibaba.com.

Alibaba.com has been an excellent wholesale supplier of air lift pump for years. The supply consists of a vast number of brands to choose from, comes in different sizes, operations, and power sources. You can get a pump for residential and large commercial applications from the collection. Whether you want a water pump for your home, or run a repair and maintenance business, and need a supply of air lif pump, you can find the product you want from the vast collection at Alibaba.com.therther it is for refrigeration, air conditioning, transfer, or a simple car wash business, anything you want, Alibaba.com has it.

An airlift pump is a pump that has low suction and moderate discharge of liquid and entrained solids. The pump injects compressed air at the bottom of the discharge pipe which is immersed in the liquid. The compressed air mixes with the liquid causing the air-water mixture to be less dense than the rest of the liquid around it and therefore is displaced upwards through the discharge pipe by the surrounding liquid of higher density. Solids may be entrained in the flow and if small enough to fit through the pipe, will be discharged with the rest of the flow at a shallower depth or above the surface. Airlift pumps are widely used in aquaculture to pump, circulate and aerate water in closed, recirculating systems and ponds. Other applications include dredging, underwater archaeology, salvage operations and collection of scientific specimens.

The only energy required is provided by compressed air.compressor or a blower. The air is injected in the lower part of a pipe that transports a liquid. By buoyancy the air, which has a lower density than the liquid, rises quickly. By fluid pressure, the liquid is taken in the ascendant air flow and moves in the same direction as the air. The calculation of the volume flow of the liquid is possible thanks to the physics of two-phase flow.

Airlift pumps are often used in deep dirty wells where sand would quickly abrade mechanical parts. (The compressor is on the surface and no mechanical parts are needed in the well). However airlift wells must be much deeper than the water table to allow for submergence. Air is generally pumped at least as deep under the water as the water is to be lifted. (If the water table is 50 ft below, the air should be pumped 100 feet deep). It is also sometimes used in part of the process on a wastewater treatment plant if a small head is required (typically around 1 foot head).

The liquid is not in contact with any mechanical elements. Therefore, neither the pump can be abraded (which is important for sandwater wells), nor the contents in the pipe (which is important for archeological research in the sea).

Cost: while in some specific cases the operational cost can be manageable, most of the time the quantity of compressed air, and thus the energy required, is high compared to the liquid flow produced.

Conventional airlift pumps have a flow rate that is very limited. The pump is either on or off. It is very difficult to get a wide range of proportional flow control by varying the volume of compressed air. This is a dramatic disadvantage in some parts of a small wastewater treatment plant, such as the aerator.

this pumping system is suitable only if the head is relatively low. If one wants to obtain a high head, one has to choose a conventional pumping system.

because of the principle, air (oxygen) dissolves in the liquid. In certain cases, this can be problematic, as, for example, in a waste water treatment plant, before an anaerobic basin.

A recent (2007) variant called the "geyser pump" can pump with greater suction and less air. It also pumps proportionally to the air flow, permitting use in processes that require varying controlled flows. It arranges to store up the air, and release it in large bubbles that seal to the lift pipe, raising slugs of fluid.

"Airlift calculation by Sanitaire (pdf document)" (PDF). sanitaire.com. 2012-01-05. Archived from the original on 2012-01-05. Retrieved 2022-06-25.link)

By Clifford E. Jones – There is no reason to pay a lot of money for a water pump when this DIY airlift pump design will do all you want. The cost is very low. The materials list is for a 100-foot well; adjust this to meet your well depth.

To start, you will need to remove the well cap. If damaged, build or buy a new one. Keep the well clean. Put four holes in the well cap. (Illustration 1.) Two holes for vents, one for the 1 ¼” discharge pipe, and one for the ½ air pipe. Screen the vents.

The discharge pipe is 1 1/4” diameter, the air pipe is 1/2“ diameter. Use adhesive and two small stainless steel screws at each connection. Make the 1-1/4” pipe the same length as the well depth. Put the end furthest from the well through the hole you made in the well cap and have it protrude out past the well cap enough to reach over your barrel top. (See illustration 2).

Now put the 1-1/4” clamp on top of the well cap. This will eventually keep the pump from dropping down the well, so make it tight and be sure it won’t slip down the hole in the well cap. Next, make the ½” line. Starting at the bottom, put on two 90 degree elbows and a 30” piece of pipe and insert it up into the 1-1-4” pipe and clamp both pipes together (Illustration 3).

Now hook up the two elbows on the 1-1/4” pipe, putting a piece of pipe over to your barrel and a short piece to point down into the barrel. Don’t poke the end of the discharge pipe into the barrel. The air needs to escape.

What is happening here is air is pumped down the small pipe and released into the larger pipe forming bubbles which rise and capture the water and bring it to the top.

You may not have a large well and can get by with a ¾” discharge pipe and a 1/4” air line. Just don’t block the bottom of the large pipe with the small one. Leave room for the water to enter.

This article wouldn’t be complete without something on the air compressor. The main effort is to put some air down the small line that is only blocked by water. Any compressor capable of pumping up an auto tire will do. Air volume is more important than great pressure. I used an automobile air conditioner pump with great success but it did pump oil, and that isn’t good. Get yourself a good air compressor.

This airlift pump design may seem like a poor man’s pump, but there are some advantages over other pumps. It won’t freeze; you can do it yourself; any servicing is done at the compressor and not down the well; and if you just happen to live past the power company, you can still have the water and not cost you an arm and a leg.

[Editor’s Note: The contents of this article have been adapted, with permission, from the innovations of Glenn Martinez of Olomana Gardens Hawaii. The author of this article, Terry Stratton, along with his wife Cyndi and Science & Tech department head Vernon Byrd serve as full-time volunteers at the University of the Nations, Hawaii. The team has over eight years of experience with the campus Natural Farm Training Center that includes building, operating, and teaching about aquaponics and airlift pump configurations for small to medium scale aquaponics systems in Hawaii, and internationally in community development settings. The following article aims to introduce the airlift pump concept and provide a basic overview of design set-up. Several additional resources have been included and further questions can be directed to Terry Stratton t.stratton@uofnkona.edu.]

Water pumps have long been a key component of the small-scale farm and are valuable labor-saving devices that offer a variety of practical applications. Pumps of different types are regularly used for water storage & filtration, irrigation, aquaculture systems, and more. While convenient and useful, pumping water does come at a cost – from the necessary consumption of energy, to the regular maintenance of moving parts. However, new developments in appropriate pump technologies offer options that can save money, increase reliability, improve longevity of equipment, and offer certain other benefits that to be presented in this article.

A conventional water pump uses mechanical rotation to directly pressurize and move water. In contrast, airlift water pumps take advantage of the relatively lighter density of air to lift water. Until recently, airlift pumps were only good for lifting water 10 - 15 cm at most, however Glenn Martinez from Hawaii has since shared with the international community easy-to-build designs that can readily lift water 2 to 3 meters in height. In certain configurations, these airlift designs can lift water much higher, even as high as 30 meters out of a subterranean well. This article will focus on just one of his fundamental configurations, referred to as the ‘pipe-in-a-pipe’ airlift pump (Figure 2). This configuration has been used most often to lift anywhere from 400 to 2000 liters of water per hour to a height of 1 to 4 meters, making it a very useful technology for a wide array of systems. As readers will note, this technology brings particular benefits to aquaponics systems, which is the intended use of these particular designs.

Figure 2: Design specifications of an example Martinez ‘pipe-in-a-pipe’ airlift water pump configuration. Credit: Glenn Martinez of Olomana Gardens Hawaii.

The ‘pipe-in-a-pipe’ airlift pump takes advantage of the fact that air injected underwater will expand as bubbles as it rises to the surface, with a 10% increase in volume from a depth of 1 meter. By confining the bubbles inside of a small diameter vertical pipe, these bubbles will act like a piston, or a syringe plunger, lifting portions of water upward as they rise. The physics involved would fill many technical papers, but the net effect is a strong upward current of water and air. The Martinez design works on the theory that larger bubbles, rather than a cloud of small bubbles, are most efficient at lifting water.

Glenn Martinez, the innovator behind the ‘pipe-in-a-pipe’ configuration of the airlift pump, has been involved for many years in teaching, designing, and building of aquaponics systems at his Olomana Gardens farm in Hawaii, as well as internationally in development settings. He also regularly consults on aquaponics project designs, and several years ago was designing an aquaponics system for a local school where it was going to be expensive to supply electricity. To make the system more affordable he invented (or as Glenn likes to say ‘rediscovered’) a way to lift the water from the fish tank up to the aquaponics grow bed with an innovative air pump configuration. Instead of running electrical conduit in a deep trench across the schoolyard, all that was required was a shallow ditch for the air pipe, quickly dug by the students. In the ditch, a 1-inch PVC pipe was installed, connecting the system to the small 60-watt air compressor located across the way in a lockable classroom. As it turned out, the airlift pump that Glenn came up with had multiple advantages for aquaponics systems and other situations where inexpensive and reliable methods of lifting water are needed.

As the story above illustrates, a conventional water pump requires that electricity be located close to the water source. Electricity and water, as we well know, can be a dangerous combination, especially where children are present. Safety, in regard to electricity in water, should be mitigated and taken seriously in any setting. The Times of India reported that as many as 30 people are killed every day in India by electrocution. One intern working on our projects in the Philippines recently asked us for advice when he was shocked twice with a conventional pump; he simply didn’t have much experience working with electrical devices, including how to arrange extension cords so they remained dry in the rainy season. Ground fault interrupt (GFI) circuits, if they are available, can decrease risk but tend to trip at inconvenient times and require monthly testing. As an alternative, the compressor for an airlift pump can easily be set up at a safe distance from the water to eliminate this potential hazard, decreasing risk substantially. Community development workers may find this particular feature of airlift pumps to be especially beneficial for promoting safety.

One of the great advantages of an airlift water pump is its ability to aerate water as it lifts it. This can be a highly beneficial feature when incorporated into fish production systems, or other scenarios where water quality conditions will benefit from more dissolved oxygen. In some small-scale aquaponics systems with low fish stocking density, the airlift pump alone will provide enough dissolved oxygen to supply the needs of the fish. Used along with a conventional aeration pump and airstones, an airlift pump can provide extra dissolved oxygen and security against the loss of fish from low dissolved oxygen levels.

Submersible water pumps and conventional external pumps are prone to clogging and need periodic cleaning including disassembly. Additionally, the sand and grit that they draw in will eventually wear out components, often necessitating replacement of the pump. The Martinez airlift pump design will not only handle small abrasives but debris nearly as large as the diameter of the inner pipe (1 to 1 1/2 inches). This means that small fish, clumps of algae, uneaten fish food, etc. are simply carried up and out through the pump. In one of our aquaponics systems, we conducted a trial in which we dumped 20 kg of coffee grounds into a tank to test the ability of the airlift to function without clogging; impressively, it passed through with no challenge. The ability to handle gravel and other debris isdemonstrated in this video by Glenn.

At the same time, the air compressor, the most expensive component of the airlift pump, is immune to anything about the water. Freshwater, saltwater, and sludge-laden water are all the same to this pump, as it sits separate from the water source. Additionally, in the case that a conventional submersible pump empties the tank, it will quickly suffer permanent damage from overheating – an air compressor in an airlift pump will just keep on running, ready for the water to return.

Diaphragm air compressors, which are ideal for airlift pumps, are also very easy to repair. Typically, all it takes is a screwdriver to replace diaphragms that wear out every few years. This is simple and much less expensive than replacing an entire conventional pump. Also, changing or moving a compressor can be as easy as unscrewing and reattaching a garden hose.

In some locations, a water pump is vulnerable to theft or vandalism. Since a 1-inch PVC pipe or length of larger diameter hose offers very little resistance to airflow, an air compressor can be located at a distance, locked separately in a building or storage box.

Airlift pumps may also save money by using less electricity. We replaced one 200-watt submersible pump with an 80-watt air compressor to run an airlift. The lower power requirement makes a solar panel powered system more feasible. Glenn has configured conventional pump systems with air injection to make dramatic cuts in the cost of lifting water 8-10 meters high. We don’t have any experience with it yet, but we’ve seen that DIY airlift pumps can also be configured to pump subterranean wells where the resistance to blockage and ease of repair characteristics would be especially valuable.

Larger volume airlift systems are possible and can be accomplished with different sized air compressors with appropriately sized pipes. Our 110-volt compressors range in size from 35 to 110 watts. Compressor selection is determined by several factors including the height the water needs to be pumped and the desired water output volume. The typical aquaponics ‘pipe-in-a-pipe’ configuration only needs an air compressor capable of generating an initial 5 psi (35 kPa) then be able to run continually at around 2 psi (14 kPa). The compressors that run our aquaponics systems produce in the range of 30 to 100 liters of air per minute. You can see from the chart below that the final water volume output of the pump depends not only on the size of the compressor but several other variables (Table 1). The 100 L/min compressor doesn’t deliver the most water because it is pumping higher out of a shallower well.

We aim to turn over the volume of our fish tanks at least once every two hours and these pumps have been more than adequate for that.  Pond supply stores or larger aquarium supply outlets may carry the preferred diaphragm style compressors (or alternately, piston air compressors) for this application.

Figure 3: Critical design consideration for the intake portion of the pump, located at the bottom of the sump well. (A.) Air intake ‘slots’ were found to be more effective than many drilled holes - yellow arrows represent air while blue arrows represent water. (B.) The curved bottom will prevent clogging of the intake pipe. (C.) Configuration of the air ‘inlet’ assembly.

“The latest version of the ‘pipe-in-the-pipe’ configuration does away with drilling many small holes. The conventional wisdom was that the many tiny air-bubbles displaced the density of water, thus the lighter water ‘floated up’. However, on a recent trip to the Philippines we did not have the tiny drill bit or small drill motor. I only had a hacksaw, so I simply made two cuts, opposite each other in the interior lift pipe. The cut was made the single thickness of the hacksaw blade and about 1 inch above the bottom opening of the larger exterior pipe (Figure 3A).”

It turns out that when the compressor is turned on, that the water between the outside casing pipe and the interior lift pipe is “pushed down” until it reaches the two opposing slits in the interior pipe. The air enters each slit (directly opposite each other) and literally cuts the water like a knife. After cutting the water, the air burst rises upward, lifting the water in the interior pipe all at once. This slug of air lifts all of the water in the interior pipe and comes out as one slug of water. After that first burst of air releases, thus clearing the interior pipe of water, additional water rushes in to fill the bottom of the ‘pipe-in-a-pipe’ pump. Once moving, the water in the interior pipe is 50% air and much lighter, so the air compressor has an easier time pumping the water.

The inner pipe is open to the source water and is cut at an angle to prevent it from being completely blocked (Figure 3B.). The bottom space below the two air slits and between the inner and outer pipe can be sealed without the use of the coupling and bushing pictured here (e.g. with a fabricated plug) but this method is convenient if the parts are available. With this approach the inner “stop” on the bushing has to be filed away to allow the inner pipe to slide all the way through while still preserving an airtight seal. The same goes for the other bushing at the top of the outer pipe.

A typical application of the airlift pump, as is the case at our Natural Farm Training Center in Hawaii, requires lifting 500 to 1000 liters of water per hour, available for gravity flow through an aquaponics system (Figure 4). In this case, the airlift pump is an excellent option, aerating the water as it is lifted into the tank above. We have labeled this set up for better understanding of the practical arrangement of the various airlift pump components

This airlift is pumping about 900 liter/hour from an IBC tank to a height of 1.8 meters to a clarifier. The vertical 3-inch PVC pipe is fed water by a ‘T’ connection to the IBC tank (Figure 3). This 3 inch pipe has a cap on the bottom and serves as a kind of ‘sump well’ for the actual ‘pipe-in-a-pipe’ pump. This well pipe, with the ‘pipe-in-a-pipe’ airlift inside, extends 80 cm below ground level (1.5 meters depth would have been better as the volume output of the pump would have increased and we could probably have used a smaller air compressor). The airlift itself is made from a 2-inch outer pipe and a 1.25-inch inner pipe. Water is pumped up and diverted into the tank while air exits out the top.

Figure 4: Martinez ‘pipe-in-a-pipe’ airlift pump configuration for use in a small-scale gravity-flow aquaponics system. This photo was taken on site at the Natural Farm Training Center, Hawaii. Note: Air compressors should always be placed above the high-water level, so no water drains into them when the power goes off.

FloNergia"s FloMov family of pumps are designed specifically for Aquaculture, Aquaponics and Hydroponics applications. They offer a well-engineered dual injector airlift pump solution that uses significantly less energy than conventional centrifugal pumps.

With a wide range of ready available sizes, these pumps serve the need of producers large and small.  Custom design solutions are available for an even wider variety of applications and sizes.

According to relevant research, it is clear that for a traditional mud pump, there will be blockage and wear during the dredging process because the flow cross-section of the blade is so large that its concentration is limited. Compressed air serves as the power source for air transportation, which can pump and transport liquid or mud through the combination of buoyancy, friction, and vacuum effects (Fu and Yan, 2004; Pei and Liao, 2010). To the best of our knowledge, the airlift system has many advantages, such as low cost, easy operation, simple configuration, no pollution to the environment, and less blockage (Chen et al., 2009; Pei and Tang, 2015). Therefore, it can be considered that the air transportation system has great potential for river and lake dredging.

Many scholars have carried out research, such as numerical simulation of the mixed fluid in the airlift system and analysis of the relationship between the injection parameter and the performance so that it has a higher matching, and thus, the performance of mud airlift is improved. Huang et al. (2017) performed a numerical simulation to study the effect of the nozzle type, injection depth, and injection hole diameter on the airlift pump, thereby improving the performance of the airlift pump. Alasadi and Habeeb (2017) then performed a numerical simulation study on the airlift pump with traditional and improved air injection devices under different intake flow rates, and the results show that the airlift pump with an improved air injection device can improve performance at higher intake flow rates. In actual operation, sufficient attention should be paid to the critical point of the solid particles carried in the bottom layer. If this is not given, it will cause blockage in the pump which will affect the performance and cause safety accidents in severe cases. When researchers study critical characteristics, they are mainly conducted from the perspective of experiments and rarely involve theoretical models. Taleb and Al-Jarrah (2017) performed an experiment to study the effect of the submergence ratio and air injection hole diameter on the performance of the airlift pump. The results showed that the performance of the airlift pump increased as the submergence ratio increased, while an injection hole diameter of 4 mm gave the highest performance. Oueslati A performed an experiment under many operating conditions, and proposed a theoretical model taking into account the air humidification and liquid temperature. The results showed that the proposed model is in good agreement with the experimental results. Fujimoto and Murakami studied the critical conditions of a mud airlift pump and obtained a model of the critical water flow rate for lifting solid particles at the bottom of the pump. By using this model, results that are consistent with reality can be obtained (Fujimoto et al., 2004). On this basis, our research team expanded the suction distance and obtained the rule of critical particle detonation. It needs to be clear that the aforementioned studies are only for water–solid two-phase flow (Tang et al., 2012). Fujimoto and Nagatani then used the aforementioned working conditions to analyze the critical conditions of particles transported in the three-phase flow. The research results show that in the three-phase flow, the starting of particles is easier, but the corresponding theoretical model is not proved (Fujimoto et al., 2005). In application, because of the constraint pressure (Pei et al., 2010; Hu et al., 2013), the particles are often compressed when they are deposited at the bottom, which makes it difficult to start the particles. At the same time, the airlift is caused to fail, but scholars rarely conduct research on this aspect.

In this study, the research is carried out. The interface selects the inlet of the airlift pump to divide the mixed water into two fluid phases, one is a water–solid two-phase flow, and the other is a gas–water–solid three-phase flow. To satisfy the actual dredging, the medium used in this study is round river sand. Based on this, the critical conditions of the three-phase flow and two-phase flow are analyzed, and the relationship between the key condition and chip compaction is analyzed. For discussion, the research result of this study can provide a reference for other researchers to study related theories.

Because the volume fraction of the solid flow cannot be calculated in the calculation, the mixed water can be regarded as a gas–water two-phase flow. On the basis of full research and analysis of the research results of Tang et al. (2012), the volume fraction of airflow can be clarified.

Figure 3 shows the calculation results of the key model, where calculated JG is equal to JG,cri. It is clear that in the water–solid two-phase flow, the critical water flow rate does not change. Therefore, JL,LS,cri ≥ JL,3,cri can be obtained. Based on this, it is possible to clarify that the condition under which the particles are lifted smoothly from the beginning of the entire flow is JL ≥ JL,LS,cri, and it will affect the critical starting condition of the particles. Based on the existence of air expansion, the mixed fluid in the gas–water–solid three-phase flow has a lower density, so JL,3,cri is smaller than JL,LS,cri, compared with the water–solid two-phase flow. Therefore, it is clear that to make the start of the particles easier, the length of the two-phase flow should be reduced. This conclusion is consistent with that of other researchers, that is, the performance of air transport can be improved by moving the intake position downward (Hattaa et al., 1998; Mahrous, 2013).

Analyzing Figure 3, it is clear that when JG,cri is increased, JL,3,cri will be reduced. After reaching the inflection point, JL,3,cri will decrease as JG,cri decreases. Therefore, by increasing JG,cri, the density of the mixed fluid can be reduced, so that the start of the particles becomes easier. Near the inflection point, because the gas value is large, the movement of the particles is mainly controlled by the water phase. From this, it can be clear that the performance of the airlift will be affected by working conditions, and it is necessary to reduce the air mass and then change the flow pattern in the tube, so that it can change from circular flow to elastic flow. It needs to be clear that this change is irreversible, that is, after reaching the inflection point, JL,3,cri will decrease with the decrease of JG,cri. According to the related research results (Hanafizadeh et al., 2011; Tang et al., 2016), the critical airlift of mud is opposite to the existence of the inflection point. In engineering applications, the inflection point needs to be moved down as much as possible. Comparing and analyzing the critical strength of particles with different diameters can be clear (Figure 3A). When the particle diameter is increased, JL,LS,cri and JL,3,cri will rise accordingly. The reason for this phenomenon is that increasing the particle diameter will increase the solid phase slip. In Figure 3B, it is clear that when the particle density increases, JL,LS,cri and JL,3,cri will rise accordingly. The reason for this phenomenon is that increasing the average density of the mixed water will reduce buoyancy. In addition, when increasing the particle density and diameter, the inflection point will move to the right (Kassab et al., 2007).

In the aforementioned model, particles need to be placed in the tube. However, in practical application, the particles will first deposit at the bottom of the water, and then they will be affected by the static chip retention effect. Obviously, the working conditions are different from those assumed by previous research. To be consistent with the practical situation, the research object selected in this study is particle B which is closest to the bottom of the pump. Figure 4 shows the force acting on particle B.

The instantaneous rate, at the moment when the particle is lifted, can still be regarded as zero. We get uS =0 and duS/dt=0. Then, the critical water flow rate uL can be calculated by Eq. 23.

Since only single particle movement is considered during lifting, the volume fraction of the solid in the tube can be ignored, and the immersion ratio γ = L3/L1 is introduced, then Eq. 23 leads to

Compared with the critical water flow model[30] we constructed, it is clear that in this model, we only consider the static chip retention force (static chip retention effect) of the particles, which is in line with the actual engineering. Using the relevant parameters shown in Table 2 to calculate, the results of the model can be clarified (Figure 5). It is clear that with the increase of particle diameter dS and density ρS, the JL,LS,cri only shows a slight upward. On the contrary, when the immersion rate γ is continuously increased, JL,LS,cri will be significantly increased. If the particle density and size are smaller, then the immersion rate γ will control the start of the particle. Analyzing Figure 5, it can be clear that if the static chip retention effect is maintained, JL,LS,cri will be increased quickly. It is concluded that for small and medium particles, the airlift performance will be affected by the static chip retention effect.

It can be considered that in areas such as oceans and lakes, because of their greater depth, the particles have a larger static chip retention force, which causes the start to fail. If the particles are compacted, then it will prevent airlift dredging. Therefore, it is necessary to impact the sand layer before airlift, so that the static chip retention effect can be reduced.

Through the aforementioned theoretical model analysis, it can be concluded that particles are easier to start in the gas–liquid–solid three-phase flow than in the liquid–solid two-phase flow. To verify this theory, critical experiments are carried out in two-phase flow tubes and three-phase flow tubes with river sand particles as the lifting medium, as shown in Figure 6.

First, the bracket is placed 5 mm from the entrance so that it is in the center of the tube. Second, particles are placed in the center of the tube to adjust the immersion depth so that the immersion rate can match the preset value. Third, the valve of the air compressor is slowly opened to allow the airflow to rise slowly. When the water at the outlet of the tube overflows, the valve is immediately closed. At this time, the critical water flow rate of the lifting solid JG,L,3,Cri can be calculated. While increasing the air volume, the distance between the particles and the support frame will gradually increase. At this time, the critical water flow rate JL,3,Cri and the corresponding air volume value JG,S,3,Cri can be calculated. In the two-phase flow experiment, a bracket is placed 5 mm below the air inlet, and the particles are placed on the support frame. Under this condition, the critical values JG,L, LS,Cri, JG,S,LS,Cri, and JL,LS,Cri of the two-phase flow are recalculated. Table 3 shows the calculation results.

If the immersion rate does not change, there is no significant difference between the critical values JG,L,LS,Cri of the two-phase flow and the critical values JG,L,3,Cri of the three-phase flow. When the immersion rate is equal to 0.8 and 0.3, respectively, the critical value of JG,L,LS,Cri and JG,L,3,Cri are approximately equal to 0.012 m/s and 0.019 m/s, respectively. Therefore, it can be considered that the key characteristics of the water–gas lift will not be affected by the position of the particles in the tube or the size of the particles. However, it needs to be clear that there are differences between the key characteristics of a slurry water–gas lift and the key characteristics of a gas lift. Compared with JG,S,LS,Cri of the corresponding particles in the two-phase flow, the critical air value of the particles in the three-phase flow, JG,S,3,Cri, is significantly lower, and when the temperature is increased, it will increase accordingly. Analyzing Table 3 shows that under the established conditions, compared with JL,LS,Cri, JL,3,Cri are always lower. Therefore, it can be considered that the water–solid two-phase flow has a greater impact on the critical characteristics of air transportation.

Comparing the experimental results and the calculated results, it is clear (as shown in Figure 7) that the experimental value of the critical water flow rate for lifting the solid is lower than that of the calculation result when only lifting the particles. This situation occurs because the tube and the pump will coalesce, expand, rupture, and re-aggregate. The bubbles will move periodically, causing mixed fluid instability along the axial direction when it rises. Ascending, its oscillation characteristic is ascending-descending-ascending, and compared with descending motion, the ascending motion is more intense. According to the results of other researchers and ours, it can be inferred (Hu et al., 2012; Hu et al., 2015) that the basic feature of a slurry airlift is the oscillating upward motion of the mixed fluid, which will cause a transient vacuum, so there will be resistance. If the particle’s fluctuation reaches its peak, then the particle’s activation state can be advanced. Figure 7 also shows that if the immersion rate is lower, the mixed fluid will have more prominent oscillation characteristics, which will result in a higher instantaneous vacuum. To confirm these phenomena, high-speed cameras can be used.

Due to the effect of gravity, the particles will be affected by the static chip retention effect when they are deposited at the bottom of the water. When we are conducting research, we put sand particles on the bottom of the pump in advance (Figure 4). At this time, the sand will be closely arranged and in a double-stacked state. To maintain the static chip retention effect, the particles need to be placed in the water continuously for 7 days. Then we adjusted the water tank and preset the immersion rate. The particles in the center of the upper layer are the object, and the key experimental steps are repeated. Based on this, we can get JG, L, LS, Cri, JG, S, LS, Cri, and JL, LS, Cri. The research results show that the particles cannot start when the air compressor valve is adjusted from close to the maximum gas flow. Therefore, it can be considered that the static chip retention effect is obvious at the bottom. Even if the pump has a large water value and the resistance imposed on the particles is small, the static chip retention force cannot be overcome, thus making it impossible to carry out an airlift. To clarify the experimental results of JL,LS,Cri, we connected the outlet of the airlift pump to a high-power centrifugal pump. Table 4 shows the comparison results of theoretical and experimental critical values. Research on the table can be clear, and the calculation results show that the experimental results of JL,LS,Cri are low. Therefore, it can be considered that the fluctuation of water flow and surface defects between adjacent particles (Figure 4) will reduce the compactness, which finally weakens the static retention effect of the chips. Therefore, it can be considered that as long as the static chip retention effect exists, it will affect air transportation, so it is necessary to take measures to eliminate it.

In this study, river sand particles were used as the lifting medium. Based on the static chip retention effect, the critical characteristics of liquid–solid two–phase flow and gas–liquid–solid three-phase flow are explored. The following conclusions can be drawn:

2) In a water-solid two-phase flow, the physical properties of the water and particles will affect the critical water rate. However, in the gas–water–solid three-phase flow, not only will the physical properties of water and particles affect the critical water rate but so will the air rate. Before the inflection point, as the air critical flow increases, the water flow will decrease. After the inflection point, as the air critical flow increases, the water flow will increase. In addition, the existence of the inflection point is not conducive to airlift.

3) On the basis of the constant immersion rate, the critical air rate of the fluid discharged to the pipe outlet is roughly the same. The physical properties of the particles will affect the corresponding water rate and critical air value. In the three-phase gas–water–solid flow, the start of the particles can be easier.

4) When there is a static chip retention effect under water, it is necessary to use auxiliary methods to impact the particle layer or to increase the resistance of the particles, otherwise, it will not be conducive to airlift.

Alasadi, A. A. M. H., and Habeeb, A. K. (2017). Experimental and numerical simulation of an airlift pump with conventional and modified air injection device. J. Eng. 23 (2), 62.

Chen, G., Ning, Y., Tang, D., and Jin, X. (2009). Study on the operation performance of pipeline air-lift system[J]. Min. Metallurgical Eng. 29 (5), 24. doi:10.3969/j.issn.0253-6099.2009.05.007

Fujimoto, H., Murakami, S., Omura, A., and Takuda, H. (2004). Effect of local pipe bends on pump performance of a small air-lift system in transporting solid particles. Int. J. Heat Fluid Flow 25 (6), 996–1005. doi:10.1016/j.ijheatfluidflow.2004.02.025

Fujimoto, H., Nagatani, T., and Takuda, H. (2005). Performance characteristics of a gas–liquid–solid airlift pump. Int. Jonalur Multiph. Flow 31 (10-11), 1116–1133. doi:10.1016/j.ijmultiphaseflow.2005.06.008

Hanafizadeh, P., Ghanbarzadeh, S., and Saidi, M. H. (2011). Visual technique for detection of gas–liquid two-phase flow regime in the airlift pump. J. Petroleum Sci. Eng. 75 (3-4), 327–335. doi:10.1016/j.petrol.2010.11.028

Hu, D., Kang, Y., Tang, C-L., and Wang, X-C. (2015). Modeling and analysis of airlift system operating in three-phase flow. China Ocean. Eng. 29 (1), 121–132. doi:10.1007/s13344-015-0009-z

Hu, D., Tang, C., Zhang, F., and Lin, Y. (2012). Theoretical model and experimental research of airlift device in borehole hydraulic jet mining[J]. J. China Coal Soc. 37 (3), 522. doi:10.13225/j.cnki.jccs.2012.03.014

Hu, D., Wu, X., Tang, C., and Liao, Z. (2013). Experimental study of airlift device for borehole hydraulic jet mining[J]. Mech. Sci. Technol. Aerosp. Eng. 32 (5), 756. doi:10.13433/j.cnki.1003-8728.2013.05.004

Huang, H., Wu, J., Yang, Z., Xue, Z., Ge, W., Wei, W., et al. (2017). A CFD simulation study of air-lift artificial upwelling based on Qiandao Lake experiment[J]. Ocean. Eng. 144, 257–265. doi:10.1016/j.oceaneng.2017.07.048

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Oueslati, A., and Megriche, A. (2017). The effect of liquid temperature on the performance of an airlift pump. Energy Procedia 119, 693–701. doi:10.1016/j.egypro.2017.07.096

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Tang, C., Hu, D., and Lin, Y. (2012). Experimental study of performance characteristics of an air-lift for conveying river sand[J]. J. Basic Sci. Eng. 20 (3), 440–445.

18 reasons why air lift pumps make so much sense and why you should seriously consider this methodology for your Aquaponics system. (Yes your home Aquaponics system will benefit as well)

Glenn will show you how to make it work, has plan books showing exactly how to do it at your place. Glenn"s air pumps will revolutionise Commercial Aquaponics.

For over 10 years I have calculated the energy efficiency of every airlift pump of which the 3 important data: (energy input driving the air pump, head and volume) were presented,

18 reasons why air lift pumps make so much sense and why you should seriously consider this methodology for your Aquaponics system. (Yes your home Aquaponics system will benefit as well)

Okay.. I will restate this….airlifts are viable alternative to submersible pumps….a method to rid ourselves of them or Turbo them for increased performance and head.

It is not just the purchase cost of the pump…it is the cost of installing the GFI or safety outlet and protective float switches to prevent running dry.

It seems to be is accept fact in literature and practice at colleges that airlifts are only practical for a maximum of 24 inches! We have posted YouTubes of water pumped 24 foot! We do four foot head and pump 1200 gallons er hour with a 60 watt air compressor (Hakko diaphragm)

Not a slogan….the Turbo is our design of adding air immediately above a submersible pump…..for GREATLY added height, twice what the submersible could do alone. We have posted YouTube videos of this and demonstrated a submersible pump and air lift “Turbo” at Murray’s March one day training. Folks built them and took them home. We pumped 15 o 20 feet high with the “Turbo Submersible/airlift combo"

We use compressed air to lift water up to 25 foot, we have tested the water in the tank (using Nitrogen to drive the Oxygen down to less than 1ppm and run the pump, shooting up 12 to 15 feet and collecting the water in a down pipe, and testing it and having raising the water 2ppm in a single pass. We ran the test for 5 minutes and raised the reading to 7ppm. That was in a 75 gallon tank pumping 400 gallons per hour.

The intake filter in our airlift compressors are checked every 90 days…..submerged water pumps every day. We have 7 year old air compressors, only rebuilt 3 in the seven years….customers, not ours. Theirs were 2 to 5 years old and fixed for $40. We throw out most submersibles, because the housing the secures the back bearing is worn out. We can replace the front, the impelller and such, but once the housing is good, trash it.

No airlift is damaged by running dry not is the pump stained or overheated, it just idles till water returns. No switches or float valves. Air lifts can be dropped into a two inch sump well, hard to get protective switches in a two to four inch well.

conclusion 2: unless airlift pump manufacturers procure real (measured, not guessed) performance data and show these in a regular pump chart, they will never obtain credibility.

Show me accurate specs on air compressors and water pumps!!! Good luck!! We test most of our pumps by measuring ACTUAL pumping speed by filling a nice gallon bucket and timing it! We test at a minimum 12 inch, 24 inch, 36” and 48” and publish our results and performance. We even post videos on YouTube of us doing the performance tests!

Wow, what happened to picking up solids? no electrical installation costs? added aeration? Only ONE Pump in the system, the airlift pumps the water and provides the aeration! everyone else has TWO pumps, one water, one air for the fish to breathe! Long life? Less wear and tear? Not being outside getting stolen? Salt water and corrosive environments not an issue with PVC airlifts and no moving parts? Never being damaged by running dry? We use airlifts to transport baby shrimp, baby fish and do it without damaging them…..what submersible pump can have life fish or shrimp go thru it? What submersible pump can you pour 1/2 inch rocks and 3 inch leaves thru without damage or concern?

Air lift pumps.....Colle and Phyllis Davis from Portable Farms.com, Aquaponic systems, have been using air lift pump systems for over 40 years. They even have a patent on the pump system, and in there Aquaponic University Course System explain the system......Didn"t know if you knew or not.

I live in the UK and would like to learn about these pumps as I am just starting to build my system, will you be publishing details in another format for non-Aussies?

FloNergia"s FloMov family of pumps are designed specifically for Aquaculture, Aquaponics and Hydroponics applications. They offer a well-engineered dual injector airlift pump solution that uses significantly less energy than conventional centrifugal pumps.

With a wide range of ready available sizes, these pumps serve the need of producers large and small.  Custom design solutions are available for an even wider variety of applications and sizes.

This pump is considered to be invented by the German engineer Carl E. Loescher, who lived in the second part of the eighteenth century. He discovered the airlift pump in1797.

The only energy required is air. This air is usually compressed by a compressor or a blower. The air is injected in the lower part of a pipe that transports a liquid. It usually bubbles into another larger diameter pipe. By gravitation the air, which has a lower density than the liquid, rises quickly. By inertia, the liquid is taken in the ascendant air flow and moves in the same direction as the air. The calculation of the volume flow of the liquid is possible under the physics of two way flow.

Airlift pump technology is superb due to its simple structure but along with its simple structure it has some problems along with simplicity. It has a weak structure its flow is also slow, irregular and disturbed its suction is also weak. It can be used for low lifts only due to weak suction.

the liquid is not in contact with any mechanical elements. Therefore, neither the pump can be abraded (which is important for sandwater wells), neither the contents in the pipe can be abraded (which is important for archeological research in the see)

cost: while in some specific case the operational cost can be interesting, most of the time, the quantity of air to compress is high compared to the liquid flow required.

This pumping system is suitable only if the head is relatively low. If you want to obtain a high head, you have to chose a conventional pumping system.

Because of the principle, a lot of air reminds in the liquid. In certain case, this can be problematic, as, for example, in a waste water treatment plant, before an anaerobic basin.

For this critical duty, MMB selected the te-sewpas pulsed air lift pump system supplied by Te-Tech Process Solutions. The self-contained unit incorporates a 4.6kW duty side channel air blower, actuated air control valves, air manifold and control panel housed within a weatherproof GRP enclosure and is delivered to site fully assembled and tested. Each pulse of air lifts a quantity of sludge and discharges it from the sludge discharge pipe. A programmable timer in the PLC allows the frequency and duration of desludging to be adjusted to allow the sludge to consolidate thus eliminating any potential ‘rat-holing’ and ensuring consistent desludging.

The unit can be located close to the tanks that it serves with flexible air delivery hoses routed through ducts to each of the desludge chambers. The air delivered is hot and as a result there is no need for thermal lagging or insulation. Each te-sewpas unit can serve up to four primary or humus tanks with typical individual air delivery hose length up to 35m.

At Stocksbridge, a single Type B te-sewpas unit with duty/standby air blowers serves the two humus tanks. Rather than using the standard control panel, MMB decided to integrate the te-sewpas controls into the central PLC and Te-Tech provided a functional design specification for this purpose. The project was completed in October 2019. “We’ve been using the air lift systems of various makes on our sites for the last 20–25 years,” says Yorkshire Water’s Wastewater Asset Planning Sponsor Jan Buczylo, “The te-sewpas is particularly robust and we decided to retrofit additional systems in place of conventional progressive cavity pumps at both Stillington and Sutton-on-the-Forest.” Installation of these two systems was completed in April 2021.

The te-sewpas system provides significant whole life cost savings when compared to conventional pumped systems. For a typical installation serving two tanks, like the Stocksbridge project, based on an estimated 25% reduction in the electrical power consumption and reduced maintenance requirements, te-sewpas provides a 40% lower capital cost and 50% reduction in operational cost compared to a pumped desludge system.

We all have heard of air-lift pumps. These pumps are usually found near agricultural lands and irrigational fields where the availability of electricity is rare and intermittent. But have you ever wondered how air can lift water and pump it from deep wells? How intermittent availability of electricity does not interfere with the operation of these air-lift pumps? Let us discuss the operating principle, advantages and disadvantages of air-lift pumps.

An air-lift pump is a device which is used to lift water from a well or a sump with the use of compressed air. The compressed air is made to mix with the water. It is well known that the density of water is more than the density of air. So it is obvious and evident that air floats higher than water or to understand better, water has more weight than air. So the main principle used in air-lift pumps is the density difference between water and air. Air is made to mix with the water and thus allowed to form froth. Froth here consists of mixture of water and air. So the density of this mixture is less than that of the water. It is the mixture of air which makes the density less than water. Thus a very small column of pure water can balance a very long column of air-water mixture. This is the working principle of air-lift pumps.

The system has a compressed air pipe with a nozzle introduced into the sump or the well. The compressed air is introduced into one or more nozzles at the foot of the delivery pipe, which is fixed in the well from which water is to be lifted. In the delivery pipe, which is partly open to the well or sump which contains water, a mixture of air and water is formed. As already discussed, this density of air and water becomes less than the density of pure water. Hence a small column of pure water is sufficient to balance a very long column of air-water mixture. This air-water mixture is discharged through the delivery pipe. The flow will continue as long as the compressed air supply is maintained.

Thus (H-h) is known as the useful lift. The results are optimum if the useful lift (H-h) is less than the height of static water (h) above the tip of the nozzle. Hence for best results,

These pumps do not require any electrical power from the power mains. Wondering how? There are systems installed in villages to irrigate agricultural fields. The system has a windmill which drives an air compressor. The compressed air from the air compressor is led into the pipe which has a nozzle in the deep wells. This system can also be modified by windmill driving a generator and power from this generator is used for compressing air and then used in these pumps.

Applications: These pumps, in spite of their poor efficiency, are commonly used in many areas where conventional pumps usage is difficult. These pumps are used in

Using compressed air is one such well development method. Most of today’s water well drill rigs come equipped with rotary screw air compressors. Reciprocating piston air compressors have been going by the wayside dating back to the mid-1980s.

“Once you know these (rotary screw air) compressors, they’re pretty simple,” says Garth Owens, president of Drill Tech Drilling & Pump Inc. in Chino Valley, Arizona. “It’s not rocket science, but it is a precision unit.”

With approximately 15 rotary screw air compressors (two piston booster compressors) on six drill rigs or as auxiliaries on 10 pump hoists, Owens has learned the mechanical intricacies of them. He has rebuilt the compressors, changed their gear sets, and replaced them on rigs while passing along his knowledge to others in the industry.

“A lot of guys who are drilling don’t even have the right air to develop a well and they’ll throw a pump down there and just try to pump out the mud,” says Garth’s son, Nick, the manager at Drill Tech. “It destroys pumps and you’re never getting that mud wall cake off the walls behind the gravel pack to really get what the well’s producing.”

“You can drill too big of a well to where the annulus is too big, and you can’t get through the gravel pack to get the walls clean. That’s a big problem. A lot of guys think the bigger the hole they go, the more gravel the better, which isn’t necessarily good because you can never get enough annular velocity to get through the gravel pack and get that mud cake off. So, you’ve got to step back and look at the big picture of your annulus to your casing size to your gravel pack.

Today’s standard rotary screw air compressor rating is at least 900 cfm or 1000 cfm/350 psi. Thirty years ago, the standard was 450 cfm/250 psi or 600 cfm/250 psi.

For example, a 750 cfm/125 psi compressor is half the compressor of a 750 cfm/250 psi compressor because the contractor is compressing the air twice as tight. Therefore, with a 750 cfm/350 psi compressor, the contractor is compressing the air an additional 50%.

To decrease the uphole velocity of 3000 feet per minute, some contractors use drill foam to clean the well at half the amount, 1500 feet per minute. “If you’re using foam and you’re filling that void, you’re taking half of that void away,” Garth Owens says. “You’re using half the air because you’re filling that void with an artificial substance. It’s going to foam up and blow out and then it’s going to evaporate and go away.”

The company conducts simultaneous swab-and-airlift with its double-swabbed development tool (see right photo) or uses high-velocity horizontal jetting.

The double-swabbed tool has perforations between the two swabs. Airlifting typically occurs through the drill pipe “from which the development swabs are suspended, so as the swabbing action brings suspended solids into the well, they are purged by the simultaneous airlift system,” writes Marvin F. Glotfelty, RG, in his book, The Art of Water Wells.

“The air comes out of the end of the drill pipe, comes up and hits that rubber swab which is the same diameter as the casing,” Garth Owens says, “and therefore all that air has to go out the perforations, blows into the gravel pack, spins that around in there, and cleans the gravel pack and cleans the borehole. Then the water comes up through the gravel pack and comes back to the perforations above your swab and comes out the top of the well.”

“We’ll actually create a vacuum and pull it between sections there,” Nick Owens says. “That’s why there’s a rubber swab above and below the holes. Typically, if you want to do an air swabber, you don’t need the rubbers because you’re just blowing it out through the perforated screen into the formation.”

The company’s high-velocity horizontal jetting tools allow it to adjust the amount of air it needs to push through them. “That way it’s blowing the air through the perforated screen, through the gravel pack, and then we’re trying to develop all that mud off there if it’s a mud hole,” Nick Owens says.

The company has an additional high-velocity jetting ball tool with approximately 20 holes each drilled to 3/16 inches around it. A high-pressure pump is used to pump freshwater down the well at 2000 psi.

“That will not only churn and turn that gravel, but it places that mud thinner all the way back to the borehole to knock off the wall cake,” Garth Owens says, “and once you’re done pressure jetting it, then you’ll come back and re-swab it and RC it all back out of there.”

Drill Tech, which had a backlog of approximately 100 wells and 30 pumps to install as of late July, stresses it all starts with the design of the well, drilling it correctly, using the right products, and not overusing polymers.

“If we’re RC drilling, we’ll mud up the top and then we’ll case the top off,” Nick Owens says. “There’s some wells out here where we live where the top 300 feet is all alluvium and there’s no water in it. We’ll mud those up, we’ll set a 300-foot surface casing, and we’ll RC drill the bottom out with just pure water because it’s just solid rock. So, we don’t use any product.

To drive home the importance of using the correct amount of product, Nick Owens recalls a large drilling company that installed two large municipal wells 10 years ago in central Arizona. It both drilled with and pumped too much polymer into the wells and was unable to get the polymer out. The wells produced 300 gpm.

“Most guys will just trip their drill pipe straight in, blow it straight up the hole, and they’re done,” he shares. “But you’ll get a lot more water out of your well, you’ll pump a lot less sand, and you’ll have a much better production well with a higher pumping level if you clean that formation out and get every bit of that mud that you put in back out again. The only way to do that is with pressure through the perforations.”

While drilling in July in California, Garth Owens also noticed large amounts of gravel being put into large diameter wells drilled using the mud rotary method. “They think that the bigger the hole is, the more gravel they put in, the better it is, which is not true. What they don’t get is the bigger the hole gets, the worse development job you can do.

“You design with maybe a 10 percent passing of sand,” he says, “and then you want to go down there and develop it until that 10 percent gets down to 0.5 percent or 0.25 percent. You want to airlift develop that until you’ve blown out everything, you’ve agitated it, washed out the gravel, washed off the wall cake, and then the ground itself and those fines come out of there.

“If you don’t do it right, you can spend three or four days pumping sand because the gravel is too coarse. You put in too coarse of a filter and the sand just keeps flowing. It takes forever, if it ever does stop. Too coarse of a sand and it’ll never stop.”

However, unlike with a reciprocating piston air compressor, Garth Owens cautions against closing the downhole valve, build maximum pressure, and jerk the valve open with a rotary screw air compressor.

“Because on a piston compressor, you just have a receiver tank that just holds air,” he says, “and you can pressure it up to 250 to 300 pounds and jerk the valve open and that big surge of air is what blows out silts and rocks when it won’t do it when steady drilling.

For years, automatic transmission fluid (ATF) was the standard for lubrication on compressors. Today, synthetic compressor oil is used because they must run at about 225 degrees to 275 degrees to vaporize the water as it sucks moisture out of the air when drilling. “It sucks all that moisture into it and it rusts up all the bearings and gears,” Garth Owens says, “so by turning the thermostat up so hot, it vaporizes and burns the condensation out of it.

“Typically, there’s three thousandths max tolerant in a screw compressor, so you really have to keep your air filters clean, your oil filters clean, and your oil good. When that tolerance starts to get loose, when you start getting a bearing wearing out or one of your screws starts wearing into the impeller of the compressor, when that tolerance starts to get loose at all, typically your oil temperatures skyrocket tremendously. It’ll run at 200 degrees for 10 years and then all of a sudden, you’re wondering why it’s running at 275 degrees and trying to cook the hoses off your rig.”

The first indication is typically losing a bearing when the oil temperature begins climbing with the tolerances getting loose. “You either have steel on steel friction, or the tolerance is so loose that after you’ve compressed this air and oil, it scoops up the air and oil and pushes it through the screw,” Garth Owens says.

“Because the tolerance is so loose, it squirts right back out of it and now you’ve built more friction, more heat, and it has to scoop it back up again. So as the screw compressor starts t