Hello.
I have used these forums many times to get answers, but have had a hard time finding someone to talk to or find relevant threads with this answer, although I am sure it is pretty basic.
I have to redesign/plumb a fertilization/acid injection line where I work (greenhouse). I will describe what is in place and what I wish to achieve and I desire someone who understands this to simply give me a heads up on which is more efficient at delivering the most water/pressure at hose end.
Currently, I have a water source from 2 wells, with primary well providing 66 gpm @ 45-65psi, and a secondary well providing 60 gpm @ 40-60 psi. The secondary well supplements the primary well on heavy watering days, which is only very occasional. It uses a pressure differential valve, I believe known as a 'clay' valve.
My water source then is piped into 4" sch 40 pvc, which is ran to a couple different injection sites. The site I am about to redisgn looks like this
|
___{}____{}____________________| 3" line
4" | 2" line
----- |
|___{}____{}____________________
2" line | 3" line
|
Where the {} is a chemical injector, which is limited to 1.25" connection and imposes approximately 12 psi loss @ 35 gpm.
This system injects sulfuric acid via the first injector and fertilizer via the second injector. After injection, each 2" line then empties into a 3" line, which in turn routes to different greenhouses for use in watering.
I have been updating our water techniques to include the use of more in-line probes and electronic injection with LMI chemical metering pumps. This allows me to write software for use with a DAQ device and grab output signals from electric pump controllers and probes to log what is happening to the quality of the water.
In changing the acid injection from water driven injection to electronic injection, manifolds for flow sensors and manifolds for probes increase the length of pipe needed in the design, not to mention valves, untions, static mixers, etc.
The problem arises because, if you note on the rude schematic above, that while each 2" line feeds a segment of 3" line, the balance of each 3" line is unequal in usage. Tht is to say, that one 3" line supplies 3x the amount of greenhouses as the other 3" line, leading to loss of flow/pressure at hose end. On very hot days our primary well cannot provide the demand, and the secondary well releases some to supplement, although in a few weeks we will be placing a frequency drive pump in the primary well that should alleviate that issue.
I aim to increase the overall flow in the 3" lines by having both 2" lines feed into the 3" lines, tie them together.
The new design calls for 2 water driven injectors for use with the fertilizer, and there is not a product that is affordable or offers relative complex free usage to replace these, unfortunately. So I need to know, which scenario below will give the most flow/pressure at hose end.
Design 1:
Each 2" line, coming from the 4" main, will pass through a single water driven injector (losing <= 12 psi) and then connect to the 3" line. The 3" line is no longer segregated as two seperate lines, but exists as one 3" line.
Design 2:
Each 2" line, coming from the 4" main, will pass through a single water driven injector (losing <= 12 psi) and then the output of these injectors will be tied together, so that one 2" line is connected to the 3" line.
Design 3:
One 2" line, coming from the 4" main, will pass through two water driven injectors, running in parallel, where the output of the injectors will join again into one 2" line, which then connects to the 3" line.
The injectors are Dosmatic A40, max 40gpm. They tell me that running these in parallel should provide a single 2" line to have a max flow then of 80gpm. My question comes up because I have the ability to design this in multiple configurations, and do not understand which method will provide the best performance.
I have contacted numerous people, from well pump to plumbers to boiler contractors to the injection manufacturers. I have recieved different answers from all of them, thus leaving me in an even more confused state. And it may be that there is not any one answer. But I would like to understand this a little bit so that on future upgrades I can design the most efficient system possible. Water is king in this business.
Thanks to anyone who might take the time to look and reply to this.
Mr Waltman.
I have used these forums many times to get answers, but have had a hard time finding someone to talk to or find relevant threads with this answer, although I am sure it is pretty basic.
I have to redesign/plumb a fertilization/acid injection line where I work (greenhouse). I will describe what is in place and what I wish to achieve and I desire someone who understands this to simply give me a heads up on which is more efficient at delivering the most water/pressure at hose end.
Currently, I have a water source from 2 wells, with primary well providing 66 gpm @ 45-65psi, and a secondary well providing 60 gpm @ 40-60 psi. The secondary well supplements the primary well on heavy watering days, which is only very occasional. It uses a pressure differential valve, I believe known as a 'clay' valve.
My water source then is piped into 4" sch 40 pvc, which is ran to a couple different injection sites. The site I am about to redisgn looks like this
|
___{}____{}____________________| 3" line
4" | 2" line
----- |
|___{}____{}____________________
2" line | 3" line
|
Where the {} is a chemical injector, which is limited to 1.25" connection and imposes approximately 12 psi loss @ 35 gpm.
This system injects sulfuric acid via the first injector and fertilizer via the second injector. After injection, each 2" line then empties into a 3" line, which in turn routes to different greenhouses for use in watering.
I have been updating our water techniques to include the use of more in-line probes and electronic injection with LMI chemical metering pumps. This allows me to write software for use with a DAQ device and grab output signals from electric pump controllers and probes to log what is happening to the quality of the water.
In changing the acid injection from water driven injection to electronic injection, manifolds for flow sensors and manifolds for probes increase the length of pipe needed in the design, not to mention valves, untions, static mixers, etc.
The problem arises because, if you note on the rude schematic above, that while each 2" line feeds a segment of 3" line, the balance of each 3" line is unequal in usage. Tht is to say, that one 3" line supplies 3x the amount of greenhouses as the other 3" line, leading to loss of flow/pressure at hose end. On very hot days our primary well cannot provide the demand, and the secondary well releases some to supplement, although in a few weeks we will be placing a frequency drive pump in the primary well that should alleviate that issue.
I aim to increase the overall flow in the 3" lines by having both 2" lines feed into the 3" lines, tie them together.
The new design calls for 2 water driven injectors for use with the fertilizer, and there is not a product that is affordable or offers relative complex free usage to replace these, unfortunately. So I need to know, which scenario below will give the most flow/pressure at hose end.
Design 1:
Each 2" line, coming from the 4" main, will pass through a single water driven injector (losing <= 12 psi) and then connect to the 3" line. The 3" line is no longer segregated as two seperate lines, but exists as one 3" line.
Design 2:
Each 2" line, coming from the 4" main, will pass through a single water driven injector (losing <= 12 psi) and then the output of these injectors will be tied together, so that one 2" line is connected to the 3" line.
Design 3:
One 2" line, coming from the 4" main, will pass through two water driven injectors, running in parallel, where the output of the injectors will join again into one 2" line, which then connects to the 3" line.
The injectors are Dosmatic A40, max 40gpm. They tell me that running these in parallel should provide a single 2" line to have a max flow then of 80gpm. My question comes up because I have the ability to design this in multiple configurations, and do not understand which method will provide the best performance.
I have contacted numerous people, from well pump to plumbers to boiler contractors to the injection manufacturers. I have recieved different answers from all of them, thus leaving me in an even more confused state. And it may be that there is not any one answer. But I would like to understand this a little bit so that on future upgrades I can design the most efficient system possible. Water is king in this business.
Thanks to anyone who might take the time to look and reply to this.
Mr Waltman.
