High Efficiency Diffuser Airlift Pump

Table 2 

 

60.5%

42.3%

10.6%

0.0%

Energy Savings by percentage of setup without diffuser

.873 watts/Gal

.151 watts/L

.484 watts/Gal

.130 watts/L

.245 watts/Gal

.065 watts/L

.151 watts/Gal

.040 watts/L

 

4.97 gpm

18.8 lpm

9.09 gpm

34.4 lpm

18.29 gpm

69.25 lpm

30.12 gpm

114.0 lpm

5

40.0 CFH

18.88 lpm

W/O Diffuser & gathering flange (similar setup as above)

.467 watts/Gal

.123 watts/L

.345 watts/Gal

.091 watts/L

.279 watts/Gal

.074 watts/L

.219 watts/Gal

.058 watts/L

.152 watts/Gal

.040 watts/L

 

16.8 gpm

63.5 lpm

23.0 gpm

87.3 lpm

28.7 gpm

108.75 lpm

37.0 gpm

140.4 lpm

53.8 gpm

204.0 lpm

10?

42.6 CFH

20.0 lpm

Liquid Flow at 5

Liquid Flow at 4

Liquid Flow at 3

Liquid Flow at 2

Liquid Flow at 1

Maximum Lift

Airflow

Alab 12 x 12 diffuser installed into 4.5 x 55 airlift pump tube with gathering flange at the bottom of the airlift pump tube.

Table 1

No
Diffuser

Then we tested the airlift pump with a 12X12 Alab fine bubble diffuser at higher airflow rates and compared it with a coarse bubble diffuser and an air hose with no diffuser at the same airflows. The test data is shown below (Test Data 1) with a plot (Figure 2) following the data:

Figure 1

The plot below (figure 1) compares the airlift pump results with no diffuser, a 3X3 diffuser and a 12X12 diffuser with the same 5 LPM airflow used in the first tests: The results indicate better performance with smaller bubbles with the same airflow.

Photo 5

Photo 4

Photo 3

Next, we tested the airlift pump with higher airflows using a 12X12 Alab fine bubble diffuser. A 17 diameter plastic funnel was used to direct the liquid entrained with bubbles into the 4.5 tube as shown in the photos below: Photo 4 shows the entire assembly while photo 3 is a close-up of the top and photo 5 is a close-up of the bottom and the diffuser.

          

          

 Our concept was that fine bubbles will improve oxygen transfer to water being pumped, compared to coarse bubbles from a hose because of the large increase in the bubble surface area.

By Alan Burris, Ph.D. and Matt Prinsen

High Efficiency Diffuser Airlift Pump