Replies to This Discussion

Permalink Reply by wyalusing jim on May 1, 2013 at 11:49am

the square "structure" is a dehydrating unit. it seperates the produced water from the gas. the little round tank on the side accumulates water until it is full, and then the water is transferred to the big tank.

the "emissions" were from the natural gas that is burned to operate the unit. if it's burning gas, the well is in production.

wj

Permalink Reply by John OBrien, landowner advocate on May 1, 2013 at 11:35pm

wj, 

It is not a dehy unit, it is a heater.  You did get a couple of things right, but for the most part you haven't a clue.  My factual explanation is below.   

If a well has a particularly high pressure there will be one of these for each lateral because they keep the gas separated until it can be metered.  Then it can go into one pipe for delivery to wherever they are sending it.

Have a great day.

Permalink Reply by John OBrien, landowner advocate on May 1, 2013 at 11:31pm

Ryan,

The small building is not a DeHy unit as WJ is saying.  It is a heater.  When the gas is being released from the ground through the well, it is going from high pressure to a lower pressure.  When a gas goes down rapidly in pressure the temperature of the gas drops relatively creating the possibility of "freeze off" in the regulator that reduces the pressure.  Therefore the need for the heater, they must raise the temperature of the gas for two reasons.  The first is so it does not freeze off and stop flow.  The second is that for the gas to be properly measured through a metering device it is required to be at standard temp for that pressure.  The "little tank" is called a separator and removes condensation from the gas and then yes it goes to the large tank for storage prior to being hauled away by the brine trucks.  This transfer process from the separator to the storage tank is usually done automatically with a float valve.  When the liquid in the tank reaches a certain level the float arm floats, and activates the dump valve.  When this happens you will hear the release from the vent pipe of the storage tank.  No smoking. lol

If you notice the two vertical black pipes at each corner of the skid with what looks like dunce caps on top.  Those are exhaust pipes from the heater burners.  The heaters burn some of the very gas coming from the well inside of a tank.  The gas passes through the tank via a coil.  It is sort of like the radiator on your car in reverse.

The 2" pipe on the right side of the building skid, with the inline red regulator is the fuel gas run for the heater.  This apparatus is outside the building because it vents gas as it regulates the low pressure for the burners, and they don't want that venting inside the structure.  That would be an accident waiting to happen. 

I love you WJ but  you haven't a clue sometimes. lol

Permalink Reply by Frank Walker on May 2, 2013 at 4:13am

PV =  nRT

Ahhh, thermo. Thou wast such a tribulation!

Brings back memories.  Hard to believe I once understood all that crap . . but never very well.  And I never used it.  Not one time.  But still remember it.  What a curse!  Seas of partial differential equations.  OMG!

Permalink Reply by Dale A. & Chad A. Shaffer on May 2, 2013 at 8:24am

Is the pics of the Southwestern pad w/ Adobe wells in Orwell / Herrick Twp.?.

Permalink Reply by wyalusing jim on May 2, 2013 at 10:46am

clueless? nah. actually that is a dehy unit, more accurately called a g.p.u. or glycol production unit.

i really didnt want to get into a technical dissertation on this, but john, since you have called my credibility into question here, it is now necessary to school you a bit on this stuff.

ok, first thing is, after looking at the picture more closely, the vertical tank behind the dehy unit is actually the sand trap. that device captures the frac sand (proppant) and any other produced solids that may come up in the gas stream before the gas enters the dehy unit to prevent them from damaging the inside of the dehy. it also captures some water which is already in a liquid form, all of which is dumped when the unit is full, either automatically or manually when the automatic system fails.

next, all marcellus wells produce water. that water must be removed to prevent freeze offs and to get the gas stream to pipeline spec.. these little dehy units do not remove all of the water necessary to bring it to spec., but they get alot of it, the midstream operators finish the dehydration to get it to interstate pipeline specs. there is an accumulator tank inside of the dehy units which purges over to the big water tank automatically.

next, there are no regulators to freeze up. regulation of these wells is done manually.

now...the dehy units do also warm the gas up. that helps to keep the temperature of the gas stream within an acceptable range for measurement purposes, but the gas does not need to be at a specific temperature for flow volume measurement purposes, the system which measures the volume of gas is temperature compensated. it reads accurately across a range of temperatures.

you also mentioned john, that there is one of these units for each well, that is not accurate either in some cases. these units are only effective up to their maximum capacity. most of them are rated at around 15 mmcfg/d. many wells here in nepa are flowing well in excess of that amount, and so require 2 or more of these units...per well.

now from a technical perspective john, if you think about it, given that the gas stream is saturated with water which needs to be removed, how would heating the gas alone accomplish this? heating the gas would raise its' saturation (dew) point and so the water would continue on in the gas stream into the midstream system causing all sorts of problems.

here is a nice explanation of the process of glycol dehydration.

http://en.wikipedia.org/wiki/Glycol_dehydration

and john, i would like to be able to take you at your word when you say that you "have worked in the industry", but when you embarrass yourself with such a simple basic fact as this, you make me wonder whether you are just making things up at times.

wj

Permalink Reply by John OBrien, landowner advocate on May 2, 2013 at 5:20pm

wj, 

Once again I realize it does no good to explain anything to you because you already know it all.  But really, pictures do not lie.  The "building" is most certainly a heater.  All high pressure wells have them.  There are most certainly regulators involved.  Just open your eyes and look at the picture of the "small building".  The device pictured on the right side of the building is most certainly a fuel gas regulator.  (Anyone who uses natural gas in their home knows this.  If you get free gas from a well, you have probably had to reset your regulator outside your house more than once.)  You can see a 2" isolation ball valve below it, and a 2' union above it.  Then a 2" 90 and it goes into "your small building".

This "small building" by the way does not have a foundation, it is on a skid and is made to be moved and used elsewhere when they finish with it here.  It is portable.

Some of what you say in your post is true of course since you wiki ed it and copied what you read.  But really wj tell me I am wrong about differential pressure metering orifices and the like.  Get over it.  If you go back and find my description of a DeHy unit and how it works you will learn something.

 Prior to the gas from the well going into this heater it most certainly goes through the separator shown behind it.  And the dump system works exactly as I stated.  I have indeed installed these appurtenances.   If you would like, we can find the driller/producer, and ask them personally who is correct.  I will bet any amount of your mineral rights against mine that I am correct!  (friend me big guy and we will go together to see one in action, then we can go to your lawyers office and you can sign over your rights) I will not post further on it regardless of your ignorant comments.  Unless of course someone who really would like to LEARN asks me to.

Now, go back to watching "I dream of Jeannie" and leave me alone

Permalink Reply by wyalusing jim on May 2, 2013 at 5:34pm

well that was just silly.

all of the dehy units on pads that i have seen are skid mounts. the ones that the midstream companies use are larger and permanently mounted.

of course that is a regulatoron the side of the dehy unit, the pressure must be controlled there for the burner inside of the unit. you said, " When a gas goes down rapidly in pressure the temperature of the gas drops relatively creating the possibility of "freeze off" in the regulator that reduces the pressure.", that sounded to me as if you were saying that the gas leaving the pad into the gathering lines went through a regulator. if that's not what you meant, then i can give you1 point.

before i make any bets with you about anything john, i first need to know if what you're betting is worth anything. so if you want to send me a prospectus, we might could have us some fun here.

now here's the first thing i did when i saw your post this morning. i called a meter tech acquaintance of mine and said take a look at this picture and tell me what you think.

"yup", he said, "that's a gpu".

he installs these things on an almost daily basis up here in nepa. so i'd welcome a third opinion if you can get one.

wj

Permalink Reply by John OBrien, landowner advocate on May 2, 2013 at 5:37pm

wj,

"I called a meter tech"  

HELP, I NEED MY WADERS!

Permalink Reply by wyalusing jim on May 2, 2013 at 6:56pm

what? you dont believe that i called him?

wj

Permalink Reply by John OBrien, landowner advocate on May 2, 2013 at 8:05pm

Here is proof, like it or not.  I can't fit all pics on one post so I will reply to my own post to add pics.

All of these photos were taken by my son, who was lead pipefitter on this job.  I was Superintendent. 

The automatic (inboard) and manual bypass (outboard) lines are clearly shown in the first picture.  You can see the instrument/power gas tubing line going to the auto dump valve.  

That line comes down from the level controller, which has a rod with a float penetrating the contactor tower.

The level controller gets its supply from the inbound tubing (instrument gas supply) which shows the manual shut off and the fisher regulator. (small gray one)  The level controller then sends power gas to the auto dump valve shown in pic 1. (inboard pipe)

All of this piping is on the contactor tower, which is imperative to the function of a DeHy unit.  (not a heater)

Attachments:

• auto,manual dumps.JPG, 122 KB
• level controler.JPG, 75 KB
• Fisher Control Valve.JPG, 118 KB

Permalink Reply by John OBrien, landowner advocate on May 2, 2013 at 8:18pm

The level controler is at the top of the picture and shown from the back side.  (It is the square box with hexagonal fitting.)

Also in the pics are simple sight glasses.  One in the pic of dumps,  has orange protective tape over the glass.  The other, in the pic of LC is shown from the side.

The Fisher control valve is the large green valve with control box.  You can see the indicator which shows the valve in the open position.

In the pic of the LC, at the bottom you can see the top of the glycol separator.  You see wj, the glycol does not all return directly to the DeHy.  Some is vaporized in the contact tower so you have to remove it with a separator.

On the pic of the dumps you can see the manual ball valve dump on the outboard, and the isolation ball valve for the auto dump valve on the inboard pipe.

In the pic of the Fisher control valve you can see the 2" return line which the glycol goes back to the DeHy skid.

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