has anyone built their own cng compressor

[ksa8907]

I've never heard of it and quite honestly, I'm skeptical if it's true. Utilities are required by state commissions to keep BTU content within a specific range, air would obviously reduce that to illegal levels.

[Piotrsko]

Originally Posted by ksa8907

I've never heard of it and quite honestly, I'm skeptical if it's true. Utilities are required by state commissions to keep BTU content within a specific range, air would obviously reduce that to illegal levels.

Be skeptical all you want, affects reality not at all. The utilities self cert for compliance, who else has the test equipment?

[ksa8907]

Originally Posted by Piotrsko

Be skeptical all you want, affects reality not at all. The utilities self cert for compliance, who else has the test equipment?

I understand your position but being quite familiar with the industry and best practices, I remain skeptical that what you're describing is truly air only.

https://algas-sdi.com/what-is-propan...20applications.

"Propane-air, also called LPG-Air or SNG, is essentially synthetic natural gas that is formed by mixing vaporized propane or LPG with air. Once mixed it forms a homogeneous mixture that can be used as a direct replacement for natural gas in combustion applications."

[windshadow]

assistance:
I do related work for a company that makes natural Gas service trucks. They have a considerable amount of old trucks sitting around. They repurpose the tanks to the newer trucks. You could find a manufacturer locally and see if they have the part you need.

[Tahoe_Hybrid]

Originally Posted by assistance

thinking of buying a $250 dollar scuba compressor (4500psi) on amazon to compress CNG for cars.

The CNG stations charge 1.60 / GGE, and homefill would be 30 cents per GGE.

The plan would be to have a flash back arrester on the intake to the compressor to prevent any accidents from going back into the main line.

Might also have a check valve to make sure the gas only goes one way.

It would appear impossible to have a flashback arrestor on the tank line due to 4500psi.

I havent been able to source cng service nozzles, i found fill ones but not the service handles like at the station, so i will be using a diy connector system that is rated for 4500psi, probably ball valves instead.

What u think of the plan?

dude it's going to take a LONG time to fill using a home gas pipe it's better to just use the station they use High pressure gas lines

the house pipe is 10psi that is at the tap

after the meter & regulator it's down to 1psi 7-10 hours fill time... if you had 10 psi at the stove the flame would be 10x bigger

source: talked to the gas man before

[ksa8907]

Originally Posted by Tahoe_Hybrid

dude it's going to take a LONG time to fill using a home gas pipe it's better to just use the station they use High pressure gas lines

the house pipe is 10psi that is at the tap

after the meter & regulator it's down to 1psi 7-10 hours fill time... if you had 10 psi at the stove the flame would be 10x bigger

source: talked to the gas man before

Lol, I am the gas man.

Residential delivery pressure is generally 0.25psig. 10psig on a house line would blow up the 2# regs that are built into most appliances and any pilot would be extinguished and blowing gas... and then kaboom goes the neighborhood.

If it's a recent gas line installation, it's probably 1/2 mdpe. I don't recall what the maximum throughput is but it would also depend on your distance from the main. In any case, residential meters will not pass more than about 500scfh.

To the OP, again, the cost to make a reliable and safe compressor will not be economically viable.

[cRiPpLe_rOoStEr]

CNG has a much higher pressure than bottled propane, so it makes me less willing to try any makeshift for CNG handling.