Retrofit Your Existing DAF with a SAF™ Generator
DAF overloaded with solids? Tired of high sewer bills? Tired of cleaning out your DAF every week? Then do what snack food manufacturer Wyandot Inc. did - Retrofit your DAF with a SAF™ Generator! With an average flow rate of 125 gpm of process wastewater, Wyandot was only achieving 50% solids removal with their overloaded DAF. Now, with a Suspended Air® Flotation (SAF™) retrofit, solids removal is consistently above 92%, and they are saving $12,000 per month on their sewer bill.
- SAF™ replaces the existing DAF pressurization / recirculation system.
- SAF™ will increase existing DAF capacity significantly, without the cost and logistical obstacles of a new installation.
- SAF™ will use significantly less power than the replaced DAF Recirculation system.
- SAF™ will remove more solids than the replaced DAF was capable of.
- SAF™ retrofit will be more flexible to operate than the replaced DAF.
- SAF™ is more cost-effective to operate than the replaced DAF.
Here’s How
- Establish a froth injection point at a location on the DAF influent line that provides adequate mixing…i.e. prior to a 90 degree elbow or within a serpentine contact chamber.
- Locate a place to stage the SAF™ Generator. Yes, it can be remotely located; but the closer the better.
- Provide potable water and electricity or compressed air as required.
- Allow space to place a container of frothing agent, and provide 110v power for a metering pump.
- Turn off the existing DAF Recirculation / Pressurization System.
Operation
- A signal will need to be provided to start the generator. This signal can be manual or a high level switch from an equalization tank.
- The SAF™ Generator will warm up for a period of 45 – 60 seconds prior to releasing froth to the process. During this period, wastewater should not be allowed to enter the flotation tank.
- The SAF™ Generator Control Panel can provide a signal to start wastewater flow when the warm-up phase is complete and the SAF™ Generator begins feeding froth to the flotation system.
- The same signal that starts wastewater flow can be used to start polymer feed, water, chain and flight skimmers, and downstream dewatering system and/or pumps.
- The flotation system can be turned off either manually or automatically by a low level switch located in the equalization tank.
Operational Costs
- Frothing agent normally costs <$0.03 per thousand gallons of wastewater treated.
- Power to run the SAF™ generator depends on suspended solids content in the wastewater; typically less than $0.10 per thousand gallons treated.
- Normally these costs are less than the cost of power consumed by the existing DAF recirculation / pressurization system
Options
- Serpentine Contact Chamber can be provided, allowing 30 seconds contact time and mixing for polymer and froth addition.
- Dewatering Conveyor can be provided to condition floated solids to the point were there is no free-draining liquid.
SAF™ Generator Sizing
| Wastewater Suspended Solids (mg/L) |
| |
500 |
1000 |
1500 |
2000 |
2500 |
3000 |
3500 |
4000 |
4500 |
5000 |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
M
a
x
i
m
u
m |
N
o
m
i
n
a
l |
| Model |
Suspended Air® Emulsion Generator Wastewater Flow Rating (gpm) |
| F2 |
100 |
100 |
50 |
50 |
34 |
34 |
25 |
25 |
20 |
20 |
17 |
17 |
14 |
14 |
13 |
12 |
11 |
10 |
10 |
8 |
| F8 |
200 |
200 |
100 |
100 |
60 |
60 |
50 |
50 |
40 |
40 |
33 |
30 |
29 |
27 |
25 |
23 |
22 |
20 |
20 |
18 |
| F25 |
1300 |
1250 |
650 |
630 |
420 |
400 |
320 |
300 |
260 |
240 |
210 |
200 |
180 |
170 |
150 |
140 |
140 |
130 |
125 |
110 |
| F50 |
2600 |
2500 |
1300 |
1200 |
850 |
800 |
630 |
600 |
510 |
490 |
420 |
400 |
360 |
350 |
320 |
300 |
280 |
250 |
250 |
210 |
| F100 |
5100 |
5000 |
2500 |
2400 |
1700 |
1600 |
1300 |
1200 |
1100 |
1000 |
850 |
800 |
730 |
700 |
630 |
600 |
560 |
530 |
500 |
450 |
| F200 |
10200 |
10000 |
5100 |
4900 |
3400 |
3200 |
2600 |
2400 |
2200 |
2000 |
1700 |
1600 |
1500 |
1400 |
1300 |
1200 |
1150 |
1050 |
1000 |
900 |
 Retrofit DAF Brochure (.pdf 70 kb)
DON’T BE FOOLED BY IMITATORS – Insist on SAF™ by Heron Innovators! | 
