Water condensation should be checked regularly as water in the pipeline will block the passage of gas.
There is no need to use any chemical. Lift the gas pipe so that the water can run back into the digester tank.
To avoid water condensation, the gas conveyer pipe from the dome towards the kitchen should be always in an upward direction. If so, water accumulation inside the conveyer pipe is negligible
Pls watch the Spoken Tutorial on Maintenance and Repair of the Biogas plant.
Also watch Spoken Tutorial on Assembly of the Biogas plant