Table 7.

Comparison of palm oil effluent methods [89].

Application method	Strengths	Weaknesses
Flatbed or long bed system	(i) Higher capacity compared to the furrow system	(i) Investment and operational costs are more expensive than the furrow system
	(ii) Suitable use in sloping/relatively flat hilly areas	(ii) Can damage palm oil trees if overfeeding is done
	(iii) Equitable distribution of waste and good soil element storage	(iii) Complicates the work of harvesters compared to furrows
	(iv) Less soil erosion effect	(iv) More pungent smell
	(v) Rarely clogged
	(vi) Low investment cost compared to sprinklers
Furrow system	(i) At the same volume, less area is required	(i) Affected by soil erosion
	(ii) Cheaper investment costs compared to sprinklers and long beds	(ii) Easy to clog and overflow
	(iii) The potential for damaging palm oil trees is more diminutive than long beds	(iii) Need control during effluent irrigation
	(iv) Suitable use in areas with clay or clay soil types	(iv) Operating costs are higher than long beds
	(v) Easier to maintain
	(vi) Do not complicate harvesters
	(vii) Increase in yield/ha/year is almost the same as sprinklers and long beds
	(viii) Relatively less smell than a long bed
Sprinkler system	(i) Sufficiently high waste delivery capacity	(i) High investment and operational costs
	(ii) Can distribute liquid waste over a large area	(ii) Need more maintenance
	(iii) Not affected by the contours of the land	(iii) Pipes can be clogged and broken
	(iv) Not affected by soil erosion	(iv) The sprinkler can get stuck due to blockage
Tanker system	(i) Cheaper investment and operational costs than other systems	(i) Potential for pollution outside the area is relatively high
	(ii) Can apply liquid waste in areas far from WWTP	(ii) Lower effluent application capacity
		(iii) Influenced by the condition of road and bridge infrastructure in the application area
		(iv) Influenced by the season
		(v) Affected by the condition of the tractor/tanker
		(vi) Application of liquid waste at any time can be stopped entirely
		(vii) Easy to clog and overflow
		(vii) Need control during waste watering