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natural compressed gas 1
- Thread starter djdijohn
- Start date
First, STOP SHOUTING, we can "hear" just fine in lower case.
The most effective natural gas powered engines are converted diesels because you need the extra compression to get the fuel dense enough to compete with petrol. You can run a gasoline (petrol) engine on natural gas, but you pay a significant loss of power.
If you "just" want to drill a gas well out back (and you have the mineral rights and you have the expertise and you have the equipment) then mother nature will give you what she gives you. That can include H2S (poison gas), CO2 (won't burn), liquid hydrocarbons (need further processing before they're useful to you), etc. Then if you are looking to use CNG you need equipment to compress it up to over 3600 psig and vessels to hold high pressure gas. At the end of the day, a "typical" 3000 ft deep well, separation equipment, deliquification equipment, storage equipment and compression equipment should cost you about $2 million. At $4/gallon and 20 miles/gallon the payout is 10 million miles.
Good luck.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
The most effective natural gas powered engines are converted diesels because you need the extra compression to get the fuel dense enough to compete with petrol. You can run a gasoline (petrol) engine on natural gas, but you pay a significant loss of power.
If you "just" want to drill a gas well out back (and you have the mineral rights and you have the expertise and you have the equipment) then mother nature will give you what she gives you. That can include H2S (poison gas), CO2 (won't burn), liquid hydrocarbons (need further processing before they're useful to you), etc. Then if you are looking to use CNG you need equipment to compress it up to over 3600 psig and vessels to hold high pressure gas. At the end of the day, a "typical" 3000 ft deep well, separation equipment, deliquification equipment, storage equipment and compression equipment should cost you about $2 million. At $4/gallon and 20 miles/gallon the payout is 10 million miles.
Good luck.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
- Thread starter
- #3
i guess i wasn't plain enough, i am looking at some property that has a gas well on it and what i want to do is to compress it enough (ncg)to put a tank in my car to run it, if there is an easy to do it, or maybe run a stationary engine for a generator, does that make more sence?
are you an engineer?
easy is really not appropriate as natural gas is a flammable gas, a gas not to be taken lightly or by the average human. the recommended course of action is to seek a responsible and competent engineer. so you know, the practice of compressing natural gas for auto usage is widespread and the equipment is available. it is a matter of being knowledgeable & capable of designing a system to meet your needs.
but before you do this, please read zdas04 response about the engine output power + other possible requirements. zdas04 is one saavy sourdough engr. you may want to change your mind.
-pmover
easy is really not appropriate as natural gas is a flammable gas, a gas not to be taken lightly or by the average human. the recommended course of action is to seek a responsible and competent engineer. so you know, the practice of compressing natural gas for auto usage is widespread and the equipment is available. it is a matter of being knowledgeable & capable of designing a system to meet your needs.
but before you do this, please read zdas04 response about the engine output power + other possible requirements. zdas04 is one saavy sourdough engr. you may want to change your mind.
-pmover
Are you buying the property with mineral and production rights? If not, forget about it. If you have mineral rights, it's still not the end of the story. Is the well is plugged? You'll have to ... well open it.... somehow. Does the state, or the Feds own the royalties? You'll have to pay for it. The state and the feds have production forms to fill out every month. You'll have to be an approved operator. You'll have to conform to the production quota? You may have to pay a good faith deposit, so you will plug it properly when it runs out of gas. You have a safety program? You have wet gas, nitrogen, CO2? You don't just go out and turn the valve on.
If it ain't broke, don't fix it. If it's not safe ... make it that way.
If it ain't broke, don't fix it. If it's not safe ... make it that way.
- Thread starter
- #6
but that is just what you do, turn the valve on and the gas is there, there several wells there and every one runs there house on gas, you own the wells and what comes out of them, i just want to go one step further and compress it for power, and thats a good point ,do the feds own any part of it, i will ck. it out before i buy, thanks
You can't use a diesel egine on natural gas, you have to have a spark ignition system. Many car companies now make CNG versions of their existing cars.
The EPA regulates conversion of an engine from gasoline to natural gas. Therefore all modifications must be tested to assure that the modification meets rules. Because of this, there are companies that make conversion kits that have been tested, but they only make them for very popular cars and trucks. You can google up and see that kits for Ford F150 trucks and Chevy trucks are available.
Once you have done the conversion, google up CNG compressors. They are pricey, but typically you take 8 hours to fill the compressed gas tank.
Gas quality can be an issue like what has been stated above, but even worse is the WATER in the gas. If you do not remove the water, when you let the pressure down from tank pressure to injection pressure, the line will freeze and you are at a dead stop.
The EPA regulates conversion of an engine from gasoline to natural gas. Therefore all modifications must be tested to assure that the modification meets rules. Because of this, there are companies that make conversion kits that have been tested, but they only make them for very popular cars and trucks. You can google up and see that kits for Ford F150 trucks and Chevy trucks are available.
Once you have done the conversion, google up CNG compressors. They are pricey, but typically you take 8 hours to fill the compressed gas tank.
Gas quality can be an issue like what has been stated above, but even worse is the WATER in the gas. If you do not remove the water, when you let the pressure down from tank pressure to injection pressure, the line will freeze and you are at a dead stop.
- Thread starter
- #8
dcasto,
Virtually all the field natural gas engines that I see are diesel conversions--that is you start with a diesel engine to get the compression ratios and then add a spark ignition system. There are exceptions like the Compressco and some GM and Ford industrial engines, but they are all very horsepower limited (e.g., the Compressco is half a Ford V-8 which is 300 hp as a V-8 on gasoline and 30 hp as a straight 4 on natural gas).
Natural gas conversion kits for gasoline engines pay a horrible price in terms of lost power. That is what I said above.
The built for purpose CNG engines have high compression ratios.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
Virtually all the field natural gas engines that I see are diesel conversions--that is you start with a diesel engine to get the compression ratios and then add a spark ignition system. There are exceptions like the Compressco and some GM and Ford industrial engines, but they are all very horsepower limited (e.g., the Compressco is half a Ford V-8 which is 300 hp as a V-8 on gasoline and 30 hp as a straight 4 on natural gas).
Natural gas conversion kits for gasoline engines pay a horrible price in terms of lost power. That is what I said above.
The built for purpose CNG engines have high compression ratios.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
- Thread starter
- #11
I wasn't trying to say that there is no hope, just that it isn't such a simple job as opening the valve, even if you do own the gas and it's clean and dry. Regulations and taxes will get you if nobody else does.
There may be hope that somebody doesn't find out, but I have found that it is just a matter of time that they do. The more time, the worse the final result.
If it ain't broke, don't fix it. If it's not safe ... make it that way.
There may be hope that somebody doesn't find out, but I have found that it is just a matter of time that they do. The more time, the worse the final result.
If it ain't broke, don't fix it. If it's not safe ... make it that way.
There are companies selling CNG vehicles - Honda has a Civic model and there are lots of commercially available conversion kits. Ford & GM will sell you a truck through their dealerships that has a factory warranty although the conversion is done by a 3rd party.
You can by a home compressor. I think these are intended to be connected to a commercial source of clean natural gas so you would probably need to add various filters/water separators.
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
You can by a home compressor. I think these are intended to be connected to a commercial source of clean natural gas so you would probably need to add various filters/water separators.
----------------------------------------
The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
Came across this article in popular mechanics (resent 2012)
Best regards
Best regards
I'm sure that the available compressor equipment takes the temperature change into account. As I recall, many of those CNG powered vehicles store the gas at very high pressures, like 10,000 psi. If you pull it out of the ground at 1000 psi and compress it to 10,000 psi, you get a significant increase in temperature. I suspect the professional equipment includes a lot of heat removal features designed into it.
Doug
Doug
Your numbers are a bit off. Typically, a "full" CNG tank is at 3600 psig. It has become quite rare for a well to have 1000 psig wellhead pressure. Some of the new shale plays see pressure significantly above 1000 psig for several years, but they are not something you "find in the backyard of a property you're purchasing". Older wells in older formations tend to have wellhead pressures closer to 25 psig and many will be lower. That is why the wellhead compressor market is flourishing in spite of very low product prices.
So if you go straight from a 25 psig well into a 3600 psig vehicle tank you need to do something like 104 compression ratios--heat of compression would take 80°F gas up to 1032°F if there was any way to do it in one stage (there isn't). This would be a pretty good 4 stage application, but I'd probably design it as a 5-stage to make sure that I could get into the tank when it is almost full.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
So if you go straight from a 25 psig well into a 3600 psig vehicle tank you need to do something like 104 compression ratios--heat of compression would take 80°F gas up to 1032°F if there was any way to do it in one stage (there isn't). This would be a pretty good 4 stage application, but I'd probably design it as a 5-stage to make sure that I could get into the tank when it is almost full.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
Oh yes, and pay attention to the first couple of lines where its stated that if you "do-it-yourself" then its a violation of the clean air act and will cost you a fine of $5000/a day you drive the car. Im not a subject expert but it seems from the article that the quality of the DIY installation is insignificant wrt the violation - its the certificate that matters.
Best regards
Morten
Best regards
Morten
zdas, no to be argumentative, but the cat engines say 3500 series, the diesel version has a 14 to 1 compression ratio and the nat gas TA (turbo) series has an 8 to 1 compression ratio and a a NA (naturally asperated) can run from 9 to 1 to 11 to 1. The diesel version of the same engine has a compression ratio of 14 to 1.
The block and crank are about the only simularities between a diesel cat and a nat gas cat. The difference is the BMEP, the diesel is higher because it has such a high CR.
The block and crank are about the only simularities between a diesel cat and a nat gas cat. The difference is the BMEP, the diesel is higher because it has such a high CR.
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