All my web research has turned up for gas compressors is either limited to 60psi or is a commercial sized rig that costs thousands. I want to SAFELY compress cleaned biomethane to about 200psi in a steel LP tank. Anyone know how for cheap?
I was recently on youtube and found a guy who was compressing it up to 150 psi using basically a cheap compressor from harbor freight and what looked to be a lot of home made stuff. He was stating in his video that he was able to get to an even higher psi, but for the video didn't want to take that long. If I come across it again I will forward the link.
I use old fridge compressors to compress biogas. They will compress up to 250 psi and are sealed so that air doesn't get in your storage. Careful though. Around 250 psi the compressor has caps that blow off (internally) incase of an over pressure situation. As for longevity for the compressors I drilled two holes, one on the top and one on the bottom so I could change out the oil. As well the gas is dried before compressing. First by condensing them through a desiccant bead. I have enough that one desiccant can be dried while the other is use. Compressing wet gas will gum the compressor.