Palm oil production by country in 1000 MT (year 2015)
Indonesia, Malaysia, Thailand and Colombia are the 4 largest producer and exporter of palm oil production. With the boom of oil palm industry, there are large quantities of biomass waste generating from palm oil mills. These main wastes are empty fruit bunches (EFB), palm oil fruits (POF), palm kernel shells (PKS), and palm oil mill effluent (POME). Taking fresh fruit bunches for example, almost 70% of them are turned into biomass wastes in forms of EFBs, fibers and shells, as well as liquid effluent in the palm oil production process.
Typical product stream distribution in oil palm mills:
|Wet FFB basis||Dry FFB basis|
|(Tonnes per hectare)||%FFB||(Tonnes per hectare)||%FFB|
|FFB (fresh fruit bunches)||20.08||100||10.6||100|
It has been a challenging task to disposal the palm oil reminders for government and investors. In some countries, due to POME contains high concentrations of protein, nitrogenous compounds, carbohydrate, lipids and minerals that could be converted into useful material using microbial process, people use it to produce bio-gas through anaerobic treating system. Solid wastes are converted into value-added products, such as biomass pellets/briquettes.
As palm oil wastes are rich in plant nutrients, they have great fertilizer values. If composted into high-quality COMPOST FERTILIZER used in the farms and vegetation areas, they will generate more additional profit for the Palm Oil Industry. Composting seems to be a practical method, and it will be helpful in recycling useful plant nutrients.
Organic Nutrition of Main Palm Oil Wastes
Nutrients content of POME (palm oil mill effluent)
Wastewater produced in palm oil milling process contains high concentration of protein, carbohydrate, nitrogenous compounds, lipids and minerals, which is the reason why POME has an extremely high content of degradable organic matter. POME also contains large amounts of N, P, K, Mg and Ca. All those elements are vital to promote plant growth.
POME can be used as fertilizer, in terms of providing sufficient mineral requirements, because of its non-toxic nature and fertilizing properties.
Characteristics of EFB (empty fruit bunches)
It is reported that, the total N, P, K content of EFB is 0.55, 0.02 and 1.28 per cent, respectively;
The micro nutrients viz., Fe, Zn, Cu and Mn were found to be 210.00, 71.00, 26.00 and 88.00 mg kg-1, respectively.
Here are 2 tables which shows more data on nutrient composition of oil palm biomass:
Table 1. Physicochemical analysis of raw POMS and EFB
|Moisture content %||85||60|
|Total organic carbon||33.0||–|
|Total nitrogen||3.6||58.9 %|
|Phosphorus (as P2O5)||0.9||0.6±0.1 %|
|Potassium (as K2O)||2.1||2.4±0.4 %|
Table 2. Nutrient composition of main oil palm biomass
|Oil palm biomass||Dry matters (tonne/hectare)||Nutrient (kg/hectare)|
|Empty fruit bunches||1.6||107.9||0.4||35.3||2.7|
Function of Compost Turner in Oil Palm Biomass Waste (EFB & POME) Composting Process
Composting is a biologically based process which is practiced to stabilize the organic matter for soil amendment (producing compost) and to protect the environment from the detrimental effects of these waste products. It is considered as an efficient waste management option with economic and environmental profits. POME & EFB will be conversed into Eco-friendly and sustainable organic manure by co-composting them with other palm oil biomass wastes or agricultural by-products to improve and sustain soil fertility. The whole composting process could simultaneously treat the solid and liquid waste from palm oil mill.
Currently, fertilizers derived from oil palm mill waste are used in few countries. In countries like Indonesia, Malaysia, the main reason to this is not because of lack of environment protection awareness, but lack of advanced composting technology and efficient composting machines.
Before introducing composting equipment, we should have a basic understanding of composting methods. Generally speaking, there are 2 main methods of composting oil palm biomass waste: Pit Method, and Windrow Method.
Full Hydraulic Compost Windrow Turner is the most appropriate equipment for EFB & POME composting in windrow system. It can turn all kinds of palm oil waste evenly by lifting, turning or spreading.
EFB should be shredded first to reduce its length. Then Piling EFB and POME into a long windrow measuring 12 x 36 x 3m. Chicken manure (around 15-20%) is often added to reduce C/N ratio-Adding 25 kg of manure per 90kg shredded EFB.
While how to mix all those organic materials evenly together?
Now it is the show time of compost turner. As we all know, compost turners can both mix raw materials and turn them. These 2 functions make compost turner an inevitable equipment in compost making process.
Full hydraulic compost windrow turner straddles and moves along the windrow. The whole process is often carried out in the open. Turning the windrow regularly to maintain an even distribution of moisture and to prevent the build-up of heat (to keep windrow temperature not above 60℃).
With the adoption of fully hydraulic windrow turner machine, the process takes a total of 7-15days (depending on the local temperature). EFB compost with chicken manure have a C/N ratio of 12:1 after 15 days of composting. The finished product-compost is dark brown, and has an earthy smell.
PS: Fermentation Inoculum of Organic Manure should be used in the whole process to speed up the progress of co-composting.