5.2 Startup

When starting the operation of a biogas plant, it is necessary to introduce an inoculum – feedstock that creates the desired microorganism environment. It is advised to use the seeding sludge from the other anaerobic treatment system with similar characteristics to the current system. This helps to quickly condition the microbes in the treatment system. If the sludge is unavailable, alternatively, animal manure can be used in the system, for example mixture of cattle dung with water or urine (in a 1:1 ratio)

Typically, about 10% of the digester volume is fed with the inoculum. Initially, mainly CO₂ is produced, so any gas produced in the first weeks will not burn. If, after one month, the gas still does not burn, it is recommended to (partly) deflate the gas storage. The methane content of the gas inside the storage will then increase much faster.