I suggest you get the datasheet for whatever device you are trying to operate, and find out what fuel specifications is it designed and/or adjustable to use. You will need a reasonably accurate specification of your biogas.
"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz
One point to remember is that biogas usually has a lower calorific value than natural gas. Thus a greater volume of biogas is required to achieve the same thermal energy as with natural gas.
So your burner will probably need modifying and the gas pipe work diameter will need to be reviewed. In sime terms you usually need pipe work with a greater diameter...
Depends on how you define biogas and how picky you want to be about burning it. Scrubbed wet gas is mostly methane just like NG, and its commonly pumped back into first-world pipelines for domestic and industrial use. This isn't an "is it possible" question as there's multiple routes to take (scrub and burn clean vs burn wet), its a matter of cost vs practicality.
In addition to mods at the burner / AFR, if the biogas is water vapor saturated, then
a)Provide low point autodrainers on the fuel gas piping
b)Add a low point weep hole in the orifice plate FE for fuel gas to prevent water liquid from pooling upstream
c)Also take note of the very low permissible biogas velocity recommended in a biogas fuel gas standard - this was discussed on E-Tips a few months ago (vaguely recall 10ft/sec max)
d)With water vapor saturated gas, you can also expect high corrosion rates in carbon steel FG piping.Else dry out this gas with a PSA dryer to avoid all these problems.
