Material Flow Cost Accounting in Palm Oil: Promoting Transparency in the Use of Materials and Appropriate Scenario in Resource Saving and Waste Reduction
Corresponding email: adidjoko@tip-ugm.org
Published at : 25 Jan 2024
Volume : IJtech
Vol 15, No 1 (2024)
DOI : https://doi.org/10.14716/ijtech.v15i1.4393
Kurniawan, M.P., Guritno, A.D., Purwantana, B., Supartono, W., 2024. Material Flow Cost Accounting in Palm Oil: Promoting Transparency in the Use of Materials and Appropriate Scenario in Resource Saving and Waste Reduction. International Journal of Technology. Volume 15(1), pp. 28-38
| Muhammad Prasetya Kurniawan | Departement of Agro-Industrial Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia |
| Adi Djoko Guritno | Departement of Agro-Industrial Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia |
| Bambang Purwantana | Departement of Agricultural Engineering and Biosystem, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia |
| Wahyu Supartono | Departement of Agro-Industrial Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia |
The sustainability aspect of the palm oil
business strategy is a significant part of dealing with changes in the future.
The rest of the processed products that have not been handled perfectly is a
form of material loss that reduces income and environmental sustainability.
Even though the company has reported and compiled its responsibilities, the actual
productivity of the company is much lower because the amount of hidden waste
has not been fully considered. This research involves companies introducing
material flow cost accounting in tracing and calculating physical resources and
financing. This method helps companies to determine the number of negative and
positive products as a basis for evaluation for saving resources and reducing
environmental impacts through reducing oil losses and increasing yields. This
effort will become a competitive advantage and encourage the ability of
business actors to increase revenue and reduce waste. Scenarios of improving
the quality of fresh fruit bunches, optimizing the sterilization process, and
increasing the amount of pulp are adaptive choices in terms of availability and
resource capacity. Dissemination of efforts and successes in improving resource
efficiency to stakeholders is vital to increasing the value and sustainability
of the palm oil business.
Material flow cost accounting; Palm oil; Resource-saving; Waste reduction
The Indonesian palm oil industry contributes significantly to foreign exchange, promotes energy sovereignty, builds people's economy, and provides employment opportunities to face the dynamics of change (Directorate General Crop Estate, 2019). On the other hand, the Indonesian palm oil industry also contributes as a source of pollutants from agricultural land residues associated with palm oil production (fertilizers, pesticides, and other hazardous wastes). Global production and demand for palm oil and its derivatives are increasing rapidly. Expansion of the palm oil business requires investment and high awareness of environmental sustainability. Therefore, Palm Oil Mills (POM) are required to produce products with predetermined quality standards, save energy during the process, and sustainably manage natural resources (Hambali and Rivai, 2017). This condition encourages more effective management techniques that increase organizational output and performance (Ministry of Environment and Forestry, 2019). Palm oil companies must make improvements to milestones, identify hotspots (areas for improvement), conserve resources, and meet the requirements for sustainable adaptation (Ghadimi, Kara, and Herrmann, 2014).
In
reality, many palm oil companies have not fully considered the relationship
between efficiency, finance, and environmental impact as a system that shows
unexpected costs (Harahap et al.,
2019). Conventional handling of waste and
by-products has contributed to saving energy resources and reducing waste.
However, this activity has not been able to balance the rate of environmental
damage because of limited technology, cost allocation, and the availability of
adequate land for waste disposal. This situation must be immediately followed
up by increasing the scope of the hidden waste value, which is still low.
Increasing resources transparency using material flow cost accounting (MFCA) is
very important to illustrate the level of waste, inventory, and cost
allocation, as has been done by Walz and Guenther
(2021), Tran and Herzig (2020), and Kokubu and Tachikawa (2013)
Various
problems, which may occur in supply chain activities, such as waste, incompatibility
of processes and results, and even fraud, can be overcome by reconciling the
calculated numbers, which sometimes become hidden things. The purpose of this
study is to analyze the production process using a material flow cost
accounting (MFCA) framework that can be used to find opportunities to reduce
material use and/or material losses, increase material and energy efficiency,
and reduce adverse environmental impacts. To our best knowledge, there has been
no studies on transparency of the materials involved in palm oil production
with the production cost approach as a form of application of material flow
cost accounting. While this topic is very important to show the value of costs
invested as waste that should be reduced for efficiency improvement. Therefore,
this study give insight on the value of negative products waste treatment cost
to encourage evaluation, improvement, and mapping of savings in the utilization
of negative products for the sustainable palm oil industry.
The main contribution of this study was
providing valuable insights for policymakers seeking to promote sustainable
practices in the palm oil industry. By identifying opportunities for reducing
waste and improving resource efficiency, policymakers can develop policies and
regulations that incentivize sustainable practices and reduce the industry's
environmental impact.
This research was conducted from March to April 2018 at the
government-owned palm oil mills (POM) and plantations in Banten Province and in
February 2020 in North Sumatra. The production system at the Banten palm oil
mill is used as the initial object of the primary data measurement and the
secondary data collection, starting from the seedling, cultivation, and
processing of palm fruit bunches through interviews, observations, and direct
calculations during the activity. Adopting the ISO 14051 standard, plant
implementers are involved in identifying achievements and evaluating
undocumented waste management. This activity has not been included in the
determination of the costs of materials, energy, and systems involved in the
quantity center. Secondary data was collected from the 2016-2018 PTPN VIII
database and annual report. Supporting data for the benchmarking, including the
processing of fresh fruit bunches, is also obtained, with a restricted permit
and authority at the Palm Oil Mills (POM) at PTPN IV North Sumatra (POM Pasir
Mandoge and POM Tinjowan) and the Ministry of Environment and Forestry Forum
for discussion on sustainable topics. The four elements used to compose an MFCA
are as follows:
1) Supply chain
of raw materials, such as fresh fruit bunches (FFB), water, and chemicals for
water treatment and laboratory consumables.
2) Process
sequence flow; there are 37 stages based on the number of groups of machines
and facilities installed in the factory; in this study, the processing chain
was simplified into five main processes for the CPO, and one for the kernel,
energy generation, and water treatment.
3) The
allocation of costs related to materials (as the basis of quantity centers) is
determined by limit and period.
4) A material
flow model is built to visualize the relative quantity, product cost, and flow
loss shown in the quantity center.
2.1. Mass and Energy Balance
All the said palm oil mills have an average installed capacity of 60
tons of FFB/hour, two work shifts, minimum production of around 2,500-3400 tons
of oil, and operate in 25 working days per month with almost 80-90 percent of
the employees being the residents. Most of the factory's products are marketed
in the form of palm oil and palm kernel for domestic use. The mass and energy
balances are prepared based on the calculated size of one ton of fresh fruit
bunches (FFB) as a functional unit. The flow and inventory of materials in the
palm oil mills are traced and calculated with variable i, the balance of
materials in mill system j, and the energy generation for the
boiler is calculated. The flow rate of the input material (fresh fruit bunches)
is expressed in the variable Fi, and the energy (steam and
electricity) from the turbine and generator is distributed to process j, and the flow rate is F_ij (Equation 1). The time of harvesting season related to fluctuations in the cost of
these materials is shown as s, where the given input i
will vary, and the maturity fraction (which determines the price) at The handling of raw materials in the processing system follows the
methodology of previous research conducted by Foong
et al. (2018) and Foong et al.
(2019) (Equation 1-5).
The amount of oil percentage and palm kernel
from input material
is determined by Equation 2.
Input material i is
processed into intermediate product p with a conversion 
. The total production rate for intermediate product p (Fp) applying technologies j is distributed to an advanced
process j' to produce final product p' (including oil recovery
treatment), as calculated by Equation 3.
The amount of intermediate product after
processing p is shown in Equation 4, where
Where B_(j^') represents the advanced process technology j? that
utilizes and manages resources to convert the intermediate product p (
This
formula is used repeatedly for several processing steps in this study. The
value of the cost estimation system becomes the most challenging part to
identify because of the lack of variation in the variations of costs
allocations involved. Based on the value of the same production-consumption
balance, all inputs to the process must be traced to the flow to output in
physical form (weight), and the costs used are based on the
plan–do-check–action (PDCA) cycle in the ISO 14051 guide (Dekamin and Barmaki, 2019; Tachikawa, 2014).
2.2. Cost Accounting
This section is to identify the
flow costs and availability of fresh fruit bunches, biomasses, intermediate
products, and fossil fuels within the mill. The search and calculation (in
units of mass and volume) are performed with the proportion of use and its
weight to be referred to in the quantity center with the following allocation:
a) Material
costs; for the materials involved (with input and output units of measurement
for MFCA analysis), including fresh fruit bunches in the initial processing,
intermediate products to product, chemicals for water treatment, and quality
testing in the laboratory. Exposure can be used to promote transparency in
material and energy flows.
b) Energy
costs; the cost allocated to energy sources, such as electricity, fuel, steam,
heat from biomass, and compression for process purposes, which are calculated
together with the energy audit.
c) System
costs; the cost allocated to material handling, employee wages and salaries,
depreciation, maintenance, overhead costs, and non-material and energy
allocations.
d) Waste
management costs; the cost allocated to handling several aspects, including
residual biomass, solid waste, palm oil mill effluent, and emissions with other
particles from boilers.
These
production costs are the primary budget components for the palm oil production
processes (Dierkes and Siepelmeyer, 2019).
2.3. Material Flow Model
The
formulation of the flow model began with determining the scope and boundaries
of the process and establishing a material flow scheme (Tran
and Herzig, 2020). Material flow analysis models have generally been
used to track production, utilization, and materials consumption (Suh and
Heijungs, 2007). Buchner et
al. (2015) emphasized the need for a comprehensive sensitivity
analysis that considers the interaction between parameters and the effect of
time delays in dynamic material flow models. The identification of the model
uncertainty is made by tracing the structure of the model and its parameters.
The assumption used in this study is that no remaining products are used after
the end of the production period, which may considerably impact the remaining amount
of the inventory used. This condition will affect the model results on the
production and inventory used. Fresh fruit bunches (FFB) must be processed as
soon as possible to anticipate the reduction of the palm oil quality; hence,
there should be no leftovers or supplies.
2.4. Formulation of Resource Saving and Waste Reduction Scenarios
The first step in this study is assessing the
hotspots (areas for improvement) for the material used in crude palm oil
production. In most palm oil mills, the produced non-product output is 70-75%,
while the rest is CPO & kernel. Palm oil mills with relatively high FFB use
require adequate facilities and infrastructure capacity to keep pace with
economic growth (usually related to infrastructure investment) and regulations
referring to, among others, ISPO (Indonesia Sustainable Palm Oil) and PROPER
(Company Performance Rating Program).
3.1. Mass and Energy Balance
The amount of energy consumption for the production process is 16.78-17.53 kWh/ton FFB is obtained from the turbine generator in the palm oil mill (POM) (at an average of 14.07 – 14.92 kWh/ton FFB), and the rest is from the State Electricity Company (PLN) supply (Figure 1). Meanwhile, fiber and shell are used as fuel for water tube boilers to produce hot steam with an average efficiency of 74.5% and feeding water of 87.6oC.
Figure 1 Material and Energy Balance of
Palm Oil Processing
The average FFB processed amount is 1,574 tons per month, with a
minimum operation of 30 tons/hour for an average processing capacity. However,
a shortage of FFB supply occurred during the data collection; thus, 10,558
tons/month were used for calculations instead. All materials involved in the
total initial input were identified as 25% product, 72% solid waste, and 84%
liquid waste from supplementary usage of production water and steam. In a
previous study, it was stated that recycling waste streams would reduce water
consumption and the amount of palm oil mill effluent (POME) by 65-68% and 67%,
respectively (Chungsiriporn, Prasertsan and Bunyakan, 2006).
3.2. Cost
Accounting
Even though the yield and
utilization of waste have increased, unwanted materials are still generated and
require considerable energy and cost to treat. With a minimum average of 10,558
tons of the processed FFB, the product capacity that can be achieved is 2,147.5
tons of CPO (20.34% yield; 1.65% loss) and 385.37 tons of kernel (3.85% yield;
oil loss of 0.5%). Therefore, the current converted average price levels are
USD 686 for CPO per tonne and USD 567 for kernels per tonne. Meanwhile, the
total expected revenue from sales is USD 1,691,689.79 (Tables 2 and 3). The
material flow cost can be seen in Supplementary 1.
Based on the mass balance and
material flow model, the negative product output consists of the following:
1. Solid waste,
such as petals, leaves, insects, dirt, and other impurities in the grading
area, which is in a minute amount compared to the number of fresh fruit bunches
(FFB), empty fruit bunches (EFB) (including fruit and oil loss in EFB
2,470±14); fiber (760±3 tonnes); and, shells (675±64 tonnes) and light
particles (±52.79 tonnes).
2. Liquid
waste, such as condensate (water and oil) from the sterilization process
(1,583±28 tonnes), effluent from the clarification (5384±443 tonnes), and
effluent from palm kernel recovery plan (hydro-cyclone 844±147 tonnes), boiler
blowdown (1,266±137 tonnes), and others (±1,055 tonnes).
Although waste management reporting and evaluation are conducted
annually, there has not been much improvement in mitigating the accumulation of
residual waste. Lagoon systems and solid waste final disposal are the most
commonly used methods in most palm oil mills due to their suitability for use
in Indonesia. These waste management methods are chosen because they require
limited technology, have low maintenance costs, are energy-efficient, and have
a simple design. However, these systems have some drawbacks, such as long
hydraulic retention times, large lagoon areas (Hayawin
et al., 2018), and the potential release of significant
amounts of greenhouse gases like methane.
One of the
discussions in this study results in the comparison between the percentage of
solid and liquid waste produced that is not much different from the output
produced by the POM Agency in North Sumatra. The average value of the negative
products is USD 537,718 (46.43%), and the value of the positive products is USD
723,706 (53.57%), along with the waste treatment costs (9.475%), including the
allocation of the costs for handling empty fruit bunches (EFB), drying process
fibers, and shells for boiler feed, and other processes for the treatment of
residual solid waste. The waste treatment costs include monetary allocations
for handling POME, around 27 percent from sterilization (fat-fit), 44 percent
from sludge decanter, and 29 percent from hydro-cyclone. This material is used
to show the value of all negative losses/products produced (Dierkes and Siepelmeyer, 2019). The most compelling finding of this study is the role of biomass
in energy cost reduction. Its contribution comes from 96% energy (85% fiber and
15% shell) and 4% from diesel, with a total efficiency of 56.05%. These results
can be used to control the level of target costs reached in real time and
introduce prompt corrections regarding the planned costs according to external
and internal changes (Burova et al.,
2021).
Another interesting finding is the potential for recovering trapped oil in each process phase and by-product to increase the oil extraction rate (OER). The trapped oil was found in empty fruit bunches (EFB) 0.31±0.08%, cakes 0.78±0.05%, nuts 0.10±0.05%, fruit in FFB 0.13±0.04 %, condensate (fat-fit) 0.16±0.04%, fiber cyclone (0.2%), light tenera dry separating (LTDS) 0.23±0.08%, and clay-bath ±0.07 % with a total oil loss of 1.67 – 1.96%. The types of losses that occur within the scope of the calculation affect the quality of the results, process losses, and quality degradation. Based on the material flow cost table (Table 3), every 0.5% increase in the oil extraction rate (OER) will increase USD 8,458.45 or USD 3.94 per tonne of CPO. It has revived the company to carry out improvement scenarios as an added value to the industry.
Table 1 Material Flow Cost of Palm Oil Processing
|
Item |
QC 1 (Grading -
loading ramp) |
QC 2 (Sterilization) |
QC 3 (Threshing) |
QC (Pressing) |
QC 5 (Clarification) |
QC 6 (Kernel
Processing) |
QC 7 (Energy
generation) |
QC 8 (Water
Treatment) |
|
Product
(total material cost in USD) |
1,192,422 |
1,202,653 |
959,021 |
787,356 |
746,962 |
715,696 |
717,638 |
723,705 |
|
Allocation
cost |
99,99% |
88.30% |
64.60% |
42.92% |
21.24% |
4.52% |
NA |
NA |
|
Waste (from
fresh fruit bunch) |
0,01% |
11,69% |
23.40% |
49.26% |
71.54% |
~74.23% |
NA |
NA |
|
System cost |
4.23 |
14,095 |
24,136 |
25,806 |
25,836 |
36,565 |
44,038 |
47,887 |
|
Energy cost |
205 |
464 |
727 |
571 |
421 |
422 |
784 |
802 |
Table
2 Total Output
and Contribution in Cost Allocation
|
Output |
Total material (ton) |
Percentage |
Total cost (USD) |
Percentage |
|
Positive product |
2726 |
24.19%* |
723,706 |
57.37% |
|
Negative product |
7854 |
75.81% |
537,718 |
42.63% |
*positive product = palm oil and kernel
Table
3 Potential Scenario for Oil Losses Reduction
|
Potential Scenario |
Main activities |
Achievement |
|
To recover trapped oil in mesocarp (residual oil
recovery system) |
(a)
Using a washing
technique at a particular temperature,
followed by pressing in the digester and screw press to recover oil |
(a)
Increased potential oil recovery/reduced oil loss |
|
(b)
Utilizing ± 7.8% of
biomass (shell and fiber); and |
(b)
more solid waste is utilized as biomass energy | |
|
(c)
Reallocating resources and schedule to conduct these
activities. |
(c)
Determination of method, quality, and quantity of palm oil
standard | |
|
To recover oil from the empty fruit bunch |
(a)
Re-sterilization of poorly recovered un-stripped bunches. |
(a)
Report of a feasibility study for remaining shell and fiber utilization as biomass energy |
|
(b)
Using aqueous extraction (water and steam) to
increase the oil extraction rate (using hydro solvent) |
(b)
Improved combustion efficiency of EFB after this treatment | |
|
(c)
Performing the setup and installation to improve the
lab-scale capacity to the pilot plant |
(c)
Collaboration with academics to conduct further
studies on oil-water emulsion using micro-separation technologies, such as column flotation | |
|
To ensure the maturity level & good handling
practices on harvesting for audit data assessment enhancement |
(a)
Enhancing harvesting strategy for bunch analysis of the minimum number of detached fruits per bunch |
(a)
Mitigation of
insufficient harvesters by estimating potential product contents of
individual FFB deliveries |
|
(b)
Strictly maintaining
audit data with harvesting round to estimate oil content before the delivery to the mill. |
(b)
Reliable assessment
and supervision system for oil recovery efficiency (ORE) from the plantation
until the mill | |
|
(c)
Cutting only ripe
bunches and ensuring no ripe is left behind |
(c)
Provision of an accurate account and information to improve
crop recovery plantation | |
|
(d)
Disseminating best
practices and supervision to picking up all loose fruits |
(d)
Reduced unstandardized
FFB in POM | |
|
To combine three potential scenarios |
(a)
Developing standard operations and procedures to drive the
roles of line managers and human resources of palm oil mills and plantation |
(a)
Adjustments to some working operations and resources based on
improvement results |
|
(b)
Developing appropriate skills and awareness of employees
and upgrading them to required
levels. |
(b)
Assessment and
monitoring conducted in the factual working situation
without less investment | |
|
(c)
Synergizing with
academics, the government, and
industry to enhance capacity building for farmer |
(c)
Requirement of assessment and policies in a coherent approach
and supported by an IT-based environment for integrated resource efficiency
analysis |
Efforts to increase
yield/oil require additional costs for material handling, labor wages, and
system maintenance have not been studied because of the limited authority of
researchers. This activity requires a continuous evaluation and contribution to
the system improvement. Recommendations and follow-up scenarios are decided
based on a quantity center analysis that does not much change the work patterns
without new technology addition, low investment, and synergies with the
increase of employee capabilities (Table 3). Reducing losses and increasing oil
yield are two scenario options that can improve the quality of fresh fruit
bunches. This can be achieved by optimizing the sterilization of empty bunches
and suppressing mesocarp. The chosen scenario aligns with previous research
conducted by Noorshamsiana et al. (2013),
Subramaniam et al. (2013), Cock et al. (2014), and Gomez et al. (2015). By implementing this
scenario, it is expected that the value of a sustainable business will
increase.
Scenario formulations for oil
loss are available by gradually expanding the scope of material flow analysis
(MFA) to material flow cost accounting (MFCA) following the given authority.
The identified 'Hotspots' will later be used to assess the success of these
efforts. Documentation of the production stage to waste handling plays a
significant role in material efficiency and waste management as the innovative
potential of alternative energy at the level of an economic entity in the
context of increasing the global significance of the transition to the circular
economy (Zaytsev et al., 2021).
3.3. Material Flow Model
The material flow model is in
line with the use of the processing costs usage model that involved materials,
labor, energy, utilities, depreciation, and other usage costs. The amount of
each use is still hard to identify because the production process runs
continuously (Let, Weng, and Wahid 2010). Improvement scenarios require
the approval and involvement of all stakeholders for the amount of material and
costs spent. To address several limitations,
such as those related to authority, documentation, and reporting capabilities,
the flow scheme is presented in a simple manner by comparing inputs and
outputs, as illustrated in Supplementary 2. This scheme provides a
comprehensive assessment of the proportion of each material and energy use,
products, by-products, waste, and losses to assess the achievement and
justification of the applied instruments, as noted by Egorova
et al. (2021).
Standardization
of improvement and calculation of resource use with sensitivity requires
technology to actualize transparency, especially regarding the price,
traceability of fresh fruit bunches, quality, process, and waste treatment as a
monitoring system for the palm oil industry and policymakers (Heryani et al., 2022). The
standardization is vital in increasing the transparency of the resources used
as these activities sometimes interfere with the processing at the factory, and
there is limited reporting authority. Therefore, these results are needed to
stimulate the integration of the analysis of each scenario using life cycle
assessments for the feasibility of a sustainable palm oil industry.
The calculation of the production process data
using information obtained from a POM in Banten showed a high percentage of
negative products (±75.81%), with a waste treatment cost of 42.63% of the
expenditure. MFCA also illustrates that the allocation of financing for
materials is a hidden waste so that the flow of supporting resources
transparency becomes the basis for evaluation, improvement, and mapping of
savings in a more detailed supply chain. Investing in research and development
to improve oil recovery and material efficiency and to identify new
opportunities for resource optimization play important role in complying with
sustainability standards such as the Indonesian Sustainable Palm Oil and
Roundtable on Sustainable Palm Oil (RSPO), which require companies to minimize
their environmental impact and promote sustainable practices. By implementing
MFCA, palm oil companies can demonstrate their commitment to sustainability,
differentiate themselves from competitors who may not be taking similar steps,
and enhancing a company's reputation among consumers and stakeholders.
The authors
gratefully acknowledge support from the Directorate of Research &
Development Universitas Gadjah Mada, Palm Oil Mill PTPN VIII Kertajaya, Palm
Oil Mill PTPN IV Pasir Mandoge, Palm Oil Mill PTPN IV Tinjowan, and the data
gathering team from Vocational School of Agro-Industry Universitas Gadjah Mada
for the support and contribution to conduct these projects.
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