CONTROL OF COMPOSTING PROCESS
The composting is normally taken to be complete when the active decomposition stage is over and the C/N ratio is around 20. If the C/N ratio of compost is more than 20, the excess carbon tends to utilise nitrogen in the soil to build cell protoplasm. This results in loss of nitrogen of the soil and is known as robbing of nitrogen in the soil. If on the other hand the C/N ratio is too low the resultant product does not help improve the structure of the soil. It is hence desirable to control the process so that the final C/N ratio is around 20.
The composting process should also be so controlled that the temperature of the decomposing mass remains between 50o-60 oC for at least a week. This ensures the destruction of any parasites or pathogens present in the decomposing mass.
During the operation of the process, aerobic conditions should be maintained by controlling the aeration so that smell & odour as well as fly problems do not arise. During turning, care should be taken to avoid dust problem.
The windrows should be located over impervious surface so that the surface water from the windrows which may contain entrained particulates & pollutants is properly collected and safely disposed of after processing. Such process leachate can also be reused in composting operation.
The rejects from the process should be disposed off at properly designed and operated sanitary landfills. The MSW should be diverted to a properly operated sanitary landfill during annual maintenance period as well as during shutdown of the plant. When the composting is carried out by controlling the various factors within the optimum range, proper quality compost will be obtained.
