INGENIEUR
BIOCOMPOSTING PLANT OPERATION
POME FROM POMETS
EFB FIBER FROM MILL
BIOCOMPOSTING PLANT ( Stacking , POME Spraying & Turning ) 45 days
Leachate LEACHATE COLLECTING SUMP
MATURED COMPOST SENT TO ESTATES
PUMP BACK TO POMETS
Figure 5 : Flow process in in a Biocomposting Plant Plant
while being turned and monitored . Mature biocompost is sent to plantations as biofertiliser . This approach benefits oil palm plantations by reducing their dependency on chemical fertilisers . Figure 5 shows the biocomposting operation flowchart .
Mesocarp fibre and palm shell products , estimated to be around 14 % and 5 % respectively of the total processed FFB , are used as fuel in the biomass boiler to generate high pressure steam . The high pressure steam is used to drive a turbine to produce power for the plant and the heat processing plant . Palm oil mills are now recognised as self-sustaining due to their ability to use existing resources from waste to generate power for plant usage .
Emission control is crucial during the operation of the biomass boiler because the emission from the boiler contains several atmospheric pollutants such as particulate matters ( PM ), black smoke , carbon monoxide ( CO ), nitrogen oxide ( NO x
) and sulphur oxides ( SO x
). To reduce the environmental impact of the emission , the installation of an Air Pollution Control System ( APCS ) is a critical component . It is also stipulated in Regulation 7 of the Environmental Quality ( Clean Air ) Regulation 2014 that the biomass boiler has to be equipped with a system to control air pollution to meet the emission standard determined by the Department of Environment ( DOE ). Commonly , a multi-cyclone dust separator system is widely used in most palm
oil mill biomass boilers as the primary air pollution system . However , to enhance the dust separation process , a few other systems have been designed and installed to facilitate the process such as a wet scrubber system , electrostatic precipitators ( ESP ), a mechanical re-cyclone , a vortex separator ( clean flow system ) and a bag filter . Figure 6 shows the electrostatic precipitator ( ESP ) system .
POME is typically the largest percentage of agricultural waste produced during palm oil production . On average , it is about 55 % mass balance in palm oil processing . POME comes from three major sources including the sterilisation process , the clarification station and the hydrocyclone operation . POME is a viscous brownish liquid mixture which contains about 95 % water , 4 % solids and 1 % residual oil . Due to the large amount produced daily , palm oil mills have to install a POME treatment facility . POME is purely non-toxic as there are no chemical substances used in processing operations . However , POME is a serious pollutant if it is not treated prior to discharge into the environment . As stipulated in the Environmental Quality Act 1974 , palm oil mills have to comply with the Environmental Quality ( Prescribed Premises ) Crude Palm Oil Regulations 1978 . Therefore , an operational license to operate a palm oil mill will consider the effectiveness of the POME treatment facility before the POME is safely discharged into the environment . There
36 VOL 87 JULY-SEPTEMBER 2021