Convert Propane to Natural Gas ?

Does anyone think it might be possible or practical to convert a Propane tractor to Natural Gas?

Nope.

Can not liquefy natural gas. The volume of the cylinders would be immense.

Ernie: What of the the kits and compressors for cars and trucks starting to catch on?

Don"t know where you get your info BUT


Liquefied natural gas - Wikipedia, the free encyclopediaen.wikipedia.org/wiki/Liquefied_natural_gas

I work for a natural gas utility company and have been in this business for 33 years now, it's going to be a very long time before the general public ever catches on to using nat-gas if ever in vehicles, the costs of converting a vehicle is beyond the means of most hard working people. It cost us $7000 per vehicle for the conversion, you can burn a lot of gasoline for that amount.

Possible, yes. Practical, probably not. Most CNG systems run around 3000 psi in the tanks. The tanks are heavy. Very thick walled.

Then you need to be able to fill the tank. There are aftermarket kits that will hookup at your house, assuming you have a NG supply. They are not cheap. Honda offered them for a while too when the did their small test fleet of CNG cars.

There are fill stations around for on road vehicles to fill, ie city buses that are CNG. Not practical for your tractor, unless you want to trailer it to a major city for every fill.

If there were more fill stations, I think there would be a lot more CNG vehicles on the road.

Rick

Forgot to add, all the vehicles on the road that I am aware of are CNG not LNG.
Rick

Sure you can liquify Natural gas, it is stored that way when there is not underground storage. The pressures are much higher than propane.

Like Bendee, I must take issue with the statement that natural gas can't be liquified. Cheniere Energy Partners has a very expensive LNG plant in Lake Charles, La., and will build another in Corpus Christi. Sasol, a South African company, has announced plans to build a $10 billion LNG plant, also in Lake Charles. This is because LNG exports to the rest of the world are expected to increase dramatically in coming years. Anyone with a few bucks sitting around might look at some of the LNG stocks, including Cheniere (symbol? LNG).

Natural gas occupies 1/1600th of its original volume/space when liquified.

JMHO, compressed natural gas vehicles are a lot nearer than you might think, especially if faces change in Washington. They're becoming fairly common where I live.

Any gas can be liquified. Pressure needs to be above the triple point of the gas, so not all gases can be liquid at ambient (1 atmosphere) pressure.

Our county is going to put in a natural gas fill station for their fleet. It will be open to the general public.

As Rick Kr mentioned, natural gas is stored about 3000 PSI, propane is a little over 100. It's doable, but you have to know what the drawbacks (if any) to having a 3000 psi tank would be.
At the Kansas State Fair, there was a semi truck at a booth set up to run on natural gas. Of course, the salesman was telling everybody all the advantages. I ask him two questions. One was how many CNG refueling stations there are on the road. He said they are expected to build SOME in the next few years. My second question was what is the PSI that CNG is stored at? He very quietly (so other lookers would hear it) mumbled 3000+ PSI, but the the next set of tanks would weigh less. (Not so sure that was reassuring)
Converting a kitchen range over to natural gas is easy. A tractor no quite so.
Exactly what advantages do you expect to have with a CNG-burning tractor?

I can see an advantage if you've got gas wells on your property and "free" gas as part of the mineral rights agreement.

carpenter, NO! With enough $$$$$$$$$$$ anything is possible. But Even if you had Free Gas @ the well head the cost of Compression will break you! and when all things are @ Best you will need a tank that is Basically the size of a standard 5 ft. Oxygen Bottle. And it will only run for a little while.
Case in Point,,,Hitch Feeders @ Guymon Okla. tried to Urutalize this back in the late 80s.. They had the Gas, thought they thought that they could use Compressed Natural Gas to power the Yard Trucks. Went All in! Every thing !
The tank in the back of each Pu was basically a 5 ft. O2 bottle it laid down in the front of the Pu bed next to the cab. The problems start from there, a full bottle of CNG woulds only power a Pu. about 15 miles! Then have to be refilled.
The Compressor was a totally a shipwreck. It takes Soooo much pressure to get Natural gas to go to liquid it is undeliverable. The maintainence cost of the Compressor ( every 1,2,3 days something needed fixing) alone caused Hitch feeders to S#it-can the whole deal, after about 18 months/2yrs.
******
Back to what you want to do here..... It is your Money, do what you like, But you WILL be throwing your Money down and endless rat hole and what you have in the end will be Costly & not that good.............................................
LP is cheap, a tank that is already on the tractor will work just nicely, fill it from your home tank or call your local LP distributor.
Later,
John A.

So just because it failed 25 years ago for someone who tried to do it on the cheap, doesn't mean anyone should ever try it again?

If the pump was breaking down every 1-3 days, either it was the wrong pump for the job or an old worn-out pump that needed to be replaced. Pump technology has improved in the last quarter-century too.

Using recycled oxygen bottles does not sound like "all in" to me. More like "cheap out." Clearly they were not large enough, and compressor problems may have contributed to the short range. Municipal vehicles carry enough CNG on board to operate for a lot more than 15 miles.

Gasoline had the same problems in its early days as CNG does now. No distribution infrastructure. Dangerous to handle. Limited range. Somehow our ancestors figured it out.

If we took the same attitude about gasoline back in the early 1900's as we do about things like CNG today, we'd still be riding horses.

Propane has more than double the energy content of natural gas per equal volume (cubic feet).

wake up guys! this country is full of natural gas and its cheap! The future isnt in wind, water, or solar power. Its in natural gas but its going to take a comon person who thinks outside the box to perfect it as a motor fuel!

MM,
The technology is there. You can by a CNG vehicle from an OEM. You can also buy bi-fuel (gasoline and CNG). They can switch back and forth easily.

The problem right now is no distribution system. If the big fuel companies had their fingers in natural gas also you would find filling stations just like gas/diesel. Big oil is not really on-board.

Current cost is 1.50/gge. gasoline gallon equivalent. MPG is basically the same. Who wouldnt want 1.50 gallon NG? Big oil companies.

Fueling is just as easy as gas. Once you get use to standing next to a 3000+psi nozzle. I still think gas is more risky. CNG if released is so rich it wont light until it is around 6-7 feet where it can gather enough oxygen. By the time it bleeds down the tank will be empty, not a whole lot of risk.

Rick

The propane as used in your tractor is liquid and contains approximately 91,000 btu/gal as compared to gasoline at 115,000 btu/gal. For equal size tanks the propane tractor will will run about 80% as long as a gasoline tractor before needing refilling. On a 100 degree day the pressure in the propane tank will be approximately 175 psi.

Methane (Natural Gas) is a little different critter since it can not be compressed at ambient temperature to liquefy. Methane must first be cooled to - 117 (minus as in below zero) degrees F after which it becomes liquid at around 668 psi. This part is not so bad however, as it warms up on a 100 degree day the tank pressure will become 5,000 + psi. As a result for vehicle use methane is typically stored in the tank as a compressed gas at approximately 3,000 psi. Since it is not liquid, the range for methane fueled vehicles even with large tanks tends to be much less than for propane or gasoline fueled vehicles.

In answer to your question: Yes methane can be used in a tractor however you will need a fuel tank and fuel system for methane. In addition you will need a high pressure pump. Home fueling stations are sold by www.CNGPUMP.com. They may be able to help you will the conversion also...don't know. The pump costs around $4,000 and is able to fill a tank in 2 - 3 hours depending on size. There are no doubt other outfits selling this equipment however, I spoke with them at a show 2 years ago and could find the literature.

Good Luck - Let us know how it turns out.

Omaha has 2 CNG filling stations, so I looked into getting a CNG vehicle for work. It appears they still only get 13 mpg, which is what my 1996 Chevy 4x4 gets, so there would be no pay back on the mileage end. The maintenance on this vehicle would be more, as not every mechanic would know how too-probably need the dealer to work on it! For me, the cost just does not pencil out!

Funny, outside the box translates to outside DC. And BO said something of that sort today. He, of course, speak with fork tongue.

I just see too many negatives for NG, buy LP is a lot cheaper than gas and you can trans fill from a home LP tank with only a hose and time. I need someone to tell me how to use the old LP kit in the barn, on an injected Chevy 350.

(quoted from post at 23:08:45 09/21/12) I just see too many negatives for NG, buy LP is a lot cheaper than gas and you can trans fill from a home LP tank with only a hose and time. I need someone to tell me how to use the old LP kit in the barn, on an injected Chevy 350.

Click to expand...

What kind of LP system on that Chevy 350? Impco is probably the most common but if it is an old Schwans truck it will have an Impco system with some unique parts and will be LP only, not dual fuel.

They are in fact working on liquid natural gas for vehicles. I saw a test vid of a LNG semi tractor last year, don't have the kink. LNG is the only way to really make it work as the amount of compressed NG to drive any distance would require a huge tank. A standard 80 CF scuba tank hold that 80 CF at 1600 psi. So about double the pressure would still would not be very much gas.


Right now the big problem is just where in the heck are you going to get LNG filled at?

It's interesting at best because if it becomes common the the demand will drive up the cost of NG.

I remember many years ago after an embargo and the first small vehicals became available like the diesel Scouts, VW's and Dodge's, plus medium duty trucks stated going diesel my dad said that this would in the long run make diesel more expensive than gas......

Rick