Balancing Multiple Digester Gas Flows

[millerbp]

I'm looking for information regarding methods for balancing biogas flows from multiple anaerobic digesters. The digesters have balloon type covers and develop ~10" wc. A few of the digesters are located further away from the common collection point and will need to have a low pressure blower to get the gas to the collection point at sufficient pressure.

Is it as simple as piping them all together at the common header and engineering the header pressures within 2" of each other? Are there any issues with installing PRVs to ensure that this happens?

Any insight/practical experience on this is greatly appreciated.

 

[gerhardl]

You will have to check with suppliers of relevant equipment and experience with this type of gas and pressures.

One item is although, as you mention, the pressure balancing arrangement for the complete installation.

I will recommend a single running pipeline from each separate collecting point/ballon to burner tank, and with a check valve near inlet end, to prevent backlash or fire spreading from headstock /burner tank.

To getting the system working properly: keeping sufficent pressure at burner side, and controlled inlet into burner tank, I think you will eiter have to ensure that pressure difference between the different sections is large enough at any time to prevent trouble, or you will have to supply control instruments and controlled opening and closing of motorized valves to shut off and supply from one pipeline at time.