Performance On Nitrogen Rich Component for Composting of Food Waste

Abstract

Nitrogen-rich components are crucial to achieving successful composting. The problem lies in the lack of comprehensive understanding and evaluation of the performance of different nitrogen-rich components used in composting food waste. The objective of this study was to evaluate the performance of nitrogen-rich components (NRC) (cow dung, tea leaves, and coffee ground) for composting food waste in terms of compost quality (temperature, moisture content, nutrients content, and plant growth height). The materials used in composting are 1kg of NRC, 1kg of black soil, 1kg of rice husk, 2kg of food waste, and 1 L of Takakura EM in every compost bin. A total of 4 composts were examined, such as compost A (cow dung), B (coffee ground), C (tea leaves), and D (blank). During the composting process, all parameters of the compost were examined, and data collected. Firstly, total nitrogen (N) content results for compost A, B, C, and D are 1.2%, 1.6%, 3%, and 0.7%, respectively, whereas total phosphorus (P) content in compost A, B, C, and D is 3.7 mg/L, 3.8 mg/L, 5 mg/L, and 3.01 mg/L. Lastly, the potassium (K) content in compost A, B, C, and D is 4.56 mg/L, 4.1 mg/L, 5.13 mg/L, and 4.6 mg/L, respectively. Based on the data analysis, Compost C is the most effective compost compared to other NRC compost.

Full text

Performance On Nitrogen Rich Component for
Composting of Food Waste
Irnis Azura Zakarya1,2*, Somendiran Muniandy1, Tengku Nuraiti Tengku Izhar1,2, Nor Anis
Nadhirah Md Nasir1, Muna’amirah Mohamad3 and Georgeta Tudor4
1Faculty of Civil Engineering & Technology, Universiti Malaysia Perlis, 02600 Arau, Malaysia
2Sustainable Environment Research Group (SERG), Centre of Excellence Geopolymer and Green
Technologies (CEGeoGTech), Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia.
3E-Idaman Sdn. Bhd. Wisma Idaman, Alor Setar, Kedah, Malaysia.
4National Instiute for Research and Development in Environmental Protection, Splaiul Independenţei
294, Bucharest, Romania, 060031
Abstract. Nitrogen-rich components are crucial to achieving successful
composting. The problem lies in the lack of comprehensive understanding
and evaluation of the performance of different nitrogen-rich components
used in composting food waste. The objective of this study was to evaluate
the performance of nitrogen-rich components (NRC) (cow dung, tea leaves,
and coffee ground) for composting food waste in terms of compost quality
(temperature, moisture content, nutrients content, and plant growth height).
The materials used in composting are 1kg of NRC, 1kg of black soil, 1kg of
rice husk, 2kg of food waste, and 1 L of Takakura EM in every compost bin.
A total of 4 composts were examined, such as compost A (cow dung), B
(coffee ground), C (tea leaves), and D (blank). During the composting
process, all parameters of the compost were examined, and data collected.
Firstly, total nitrogen (N) content results for compost A, B, C, and D are
1.2%, 1.6%, 3%, and 0.7%, respectively, whereas total phosphorus (P)
content in compost A, B, C, and D is 3.7 mg/L, 3.8 mg/L, 5 mg/L, and 3.01
mg/L. Lastly, the potassium (K) content in compost A, B, C, and D is 4.56
mg/L, 4.1 mg/L, 5.13 mg/L, and 4.6 mg/L, respectively. Based on the data
analysis, Compost C is the most effective compost compared to other NRC
compost.
1 Introduction
Composting is the biological breakdown of wastes made of organic materials from plants or
animals under controlled conditions until they are stable enough to be stored and used [1]. A
key factor in successful composting is the presence of nitrogen-rich components, as nitrogen
plays a crucial role in the decomposition process and the quality of the final compost [2]. The
objective of this research is to investigate and evaluate the performance of different nitrogen-
rich components for composting food waste. By comprehensively analysing the effectiveness
* Corresponding author: irnis@unimap.edu.my
© The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons
Attribution License 4.0 (htt
ps
://creativecommons.or
g
/licenses/b
y
/4.0/).
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

and efficiency of these components, valuable insights can be gained to optimize the
composting process and improve the quality of the resulting compost.
The selection of suitable nitrogen-rich components is crucial in achieving successful
composting. Different materials such as cow dung, coffee ground and tea leaves have been
recognized for their high nitrogen content and potential contributions to the composting
process [2]. However, a comprehensive understanding of their performance is currently
lacking. This research aims to address this knowledge gap by evaluating and comparing the
performance of these nitrogen-rich components. Therefore, analysing the nutrient
composition, specifically nitrogen content, of the resulting compost will provide insights into
the effectiveness of the nitrogen-rich components in enriching the compost with essential
plant nutrients. Initially, the chemical characteristics of each NRC will be examined before
using it in the compost. Based on their chemical characteristics, three NRC, such as tea
leaves, cow dung, and coffee ground, were chosen to be used in this composting process.
During the composting, each compost containing different NRC was tested for its physical
and chemical characteristics to evaluate the most effective compost that contained nitrogen
as its main element. This research will contribute to the knowledge gap in NRC composting
by detailing the NRC chemical characteristics and how they contribute to the performance
of composting.
The outcome of this research will contribute to the advancement of sustainable food
waste management practices by providing information on the performance of nitrogen rich
component (cow dung, coffee ground and tea leaves) by analysing the physical and chemical
properties of these compost where involved parameters nutrient content (N, P, K) and the
plant growth measurement.
2 Material and Method
2.1 Nitrogen Rich Component
The NRC used in this study are cow dung, coffee ground and tea leaves with an amount of
1kg each. Cow dung was and tea leaves were collected from laboratory while spent coffee
ground were collected from Starbucks, Kangar Jaya, Perlis. The spent coffee ground was
dried under sunlight for 1 day before composting due to higher moisture content. This was
done to avoid any disturbance to the compost due to its moisture content. All these NRC
were weighted to be 1kg before composting.
2.2 Composting Method
Aerobic composting was used in this study where the usage of air circulation is crucial for
decomposition of food waste. Figure 1 shows the composting bin that was poked with several
holes to enable air circulation. The compost bin was made of HDPE material. It also won’t
affect the chemical composition of the compost. Others component needed for composting
such as effective microorganisms (EM), NRC, food waste (FW), black soil (BS) and rice
husk (RH) are prepared with following ratio for each compost A, B, C and D:
I. Compost A: (1kg BS + 1kg FW + 1kg RH +1L EM + 1kg Cow Dung)
II. Compost B: (1kg BS + 1kg FW + 1kg RH +1L EM + 1kg Coffee Ground)
III. Compost C: (1kg BS + 1kg FW + 1kg RH +1L EM + 1kg Tea leaves)
IV. Compost D: (1kg BS + 1kg FW + 1kg RH +1L EM)
2
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

(a) (b)
Fig. 1. Compost Bin Setup (a) Composting bin used and (b) Holes drilled on compost bin
All the compost was prepared and placed in the compost bin according to the content
above. The compost material will be mixed well and let it to rest for the process to begin.
The compost bin will be placed in an area without direct sunlight exposure and room
temperature. The compost microbial activity will be examined by the presence of white
structure on the compost after 1 or 2 days of composting. This white structure formation
indicates the presence of microbial activity in the compost. Addition of food waste will be
made weekly 3 times continuously for 1 month. Mixing and turning will be done daily for
aeration that provide oxygen for microorganism for microbial activity, moisture distribution
and temperature regulation. Compost sample A, B, C and D will be taken every 3 days once
until the end of composting period to analyse the chemical and physical properties of the
compost.
2.3 Plant Growth
Plant growth and number of leaves analysis was done to determine the most effective and
efficient compost fertilizer to be used in plantation. Thus, we had chosen Ipomoea aquatica
(water spinach) plant seeds to plant growth to examine the plant growth height and number
of leaves growth. The plant’s seeds were planted in the seedling tray. Each of the seedling
tray’s pot were placed about ¾ quarter of compost and ¼ quarters of black soil. The plant
was watered daily. The growth was monitored and recorded every 4 days.
3 Results and Discussion
Evaluation and comparison of the performance on nitrogen rich component for composting
of food waste was done by analysing the physical and chemical characteristics (nutrient
content and plant growth height) of the compost fertilizer.
3.1 Total Phosphorus (P) during composting
The Figure 2 shows the effect of total nitrogen during composting process of four different
sample namely A, B, C and D. In general, it can be seen that all the compost had an increment
trend that shows the nitrogen content had increased gradually over the compost period of 33
days. The initial N value for compost C higher compared to other nitrogen material.
3
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

Fig 2. Total nitrogen during composting process
The initial value of all the compost is stated to be more than 0.6% which is considered
above the suggested range for compost based on previous research [3]. The slight depletion
in the graph for all the compost may cause by the microorganism present in the compost use
nitrogen during the process to build up cells which caused the depletion in the amount of
nitrogen in the early stages of composting process which was experienced in research
conducted previously [4]. After a slight depletion, the graph of all compost continuously
increased. During the process of building up cells, some of these organisms die and are
recycled as nitrogen. Thus, this contributes to the increase of nitrogen content due to stored
source of nitrogen [5, 6]. Besides, the increase in nitrogen content is caused by an increase
in inorganic nitrogen because of the concentration effect as a consequence of strong
degradation of organic carbon compound [5]. Compost C had achieved the highest N
percentage among all the compost. Compost C final nitrogen percentage is 3% which is in
the suggested range which is more than 0.6% [3].
3.2 Total Phosphorus (P) during composting
Figure 3 shows phosphorus data for composting. Generally, the graph shows a continuous
increment phase as it approaches the end day of composting. The highest initial value
obtained by compost B with 1.86 mg/L while lowest initial value obtained by compost C
with 1.06 mg/L. Whereas, the highest final P concentration obtained by compost C with 4.2
mg/L and lowest P concentration obtained by compost D with 3.01 mg/L.
The increase in the phosphorus during composting was possibly caused by concentration
effect arising from the higher rate of carbon loss that occurs when organic matter is
decomposed [7]. Although, all the compost experiences an increment phase along the
composting period but the final composting period considered to be lower due to leaching
out the P in organic substances where in research stated that decrease in amount of P may
results in leaching out P as soluble organic solute [8]. Another possible reason for lower P
concentration caused by the formation of insoluble phosphorus compounds during
composting [9].
0
0.5
1
1.5
2
2.5
3
3.5
135810 12 15 17 19 22 24 26 29 31 33
Total Nitrogen( %)
Composting Time (Day)
A B
4
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

Fig 3: Total Phosphorus (P) during composting
Compost C had achieved a highest P concentration among all compost sample. The high P
concentration value affect by the high loss of carbon happen during the decomposition of
organic substances [10].
3.3 Total Potassium (K) during composting process
Figure 4 shows effect of total potassium during the composting process for four different
composts namely A, B, C and D. Generally, the graphs show an increase trend where it can
be seen that total potassium of all compost increases gradually. The initial K value for all
compost ranges from 2.3 mg/L to 3.3 mg/L. There is a slight fluctuation in the graph
increasing pattern as it moving towards the end of composting period. The final K value for
all the compost ranges from 4.5 mg/L to 5.1 mg/L. This value shows that there is a significant
increase in the value at the end of composting period with highest K value at the end of
composting obtained by compost C.
Fig 4: Total Potassium (K) during composting
The increase was due to the higher microbial activity in all compost which consequently
caused a higher rate of mineralization [3]. It is important to note that parameter such as
1
1.5
2
2.5
3
3.5
4
4.5
135810 12 15 17 19 22 24 26 29 31 33
TOTAL PHOSPHORUS (MG/L)
COMPOSTING TIME (DAY)
A B
2
2.5
3
3.5
4
4.5
5
5.5
135810 12 15 17 19 22 24 26 29 31 33
Total Potassium (mg/L)
COMPOSTING TIME (DAY)
A B C D
5
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

temperature, moisture content and pH affects the potassium concentration in the compost
[11]. The fluctuation in the graph along with the gradual increase caused by the activity of
microorganisms in compost can be unstable, which can cause fluctuations in the total
potassium content reading. The total potassium during the composting process had shown a
positive result for all the compost. However, compost C achieved the highest potassium (K)
concentration compared to others compost sample.
3.4 Plant Growth Height Measurement
Figure 5 shows the pattern of Ipomoea Aquatica or also known as water spinach plant height
over planting time about 32 days. This plant height study was done on four different compost
sample name A, B, C and D to study their effectiveness in contributing to the plant growth.
At initial, all the compost had 0 cm growth because we had planted using seeds of the water
spinach plant. On the 4th day of planting, there were significant growth in all compost sample
where the highest growth was noticed to be on compost C with the height value of 1.1 cm
while the lowest growth was noticed to be on compost B with 0.5 cm. On the mid of planting
day which was on day 16, it was noticed that all the plants in all compost had a good
increasing significant growth. Compost C again managed to get highest growth in height
after 16 days of planting with the height of 4 cm.
Fig 5: Measurement of plant growth measurement
There was a sudden fall for compost B sample where it had a steep fall after day 22 of
planting. During this time, it was noticed that Compost B plant had wilted suddenly. This
might have caused by the potassium(K) concentration was noticed to be lower compared to
other compost during the time period of wilting where there was a significant concentration
different when compared to other compost. Compost C had the highest initial and final height
growth in overall. Compost C had the best results in the graph analysis for the measurement
of effectiveness of compost fertilizer using in term of plant growth height.
Conclusion 4
In conclusion, Compost C had achieved to most optimal physical and chemical parameter for
compost when compared to other compost. Compost C achieved highest and most optimal
0
1
2
3
4
5
6
7
04812 16 20 24 28 32
Plant Height(cm)
PLANTING TIME(DAYS)
A B
6
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003

range when compared to other compost with 3% for nitrogen, 5 mg/L for phosphorus and
5.13 mg/L for potassium. Moreover, Compost C had attained with the highest plant growth
in term of height with 5.9 cm after 32 days of planting. To conclude this research, Compost
C or tea leaf compost is the most effective and efficient compost among all the other nitrogen
rich compost.
Acknowledgement
The authors would like to extend their gratitude to the E-Idaman Sdn. Bhd under grant
(2019/12/001) for their assistance and kindness during the sampling collection and testing.
Special thanks to the Faculty of Civil Engineering & Technology at UniMAP for providing
the laboratory facilities for this study.
References
1. M. Díaz, M. E. Eugenio, L. Jiménez, E. Madejón, and F. Cabrera, Modelling
vinasse/cotton waste ratio incubation for optimum composting, Chemical Engineering
Journal 93, 3 (2003)
2. G. Bélanger et al., Nitrogen availability from dairy cow dung and urine applied to forage
grasses in eastern Canada, Canadian Journal of Plant Science, 95, 1 (2015)
3. H. Hamid et al., Organic Fertilizer from Food Waste by Composting in UTHM Campus
Pagoh, Journal of Design for Sustainable and Environment, 1, 1 (2019)
4. S. N. B. Khalib, I. A. Zakarya, and T. N. Tengku Izhar, Composting of Garden Waste
using Indigenous Microorganisms (IMO) as Organic Additive, International Journal of
Integrated Engineering 10, 9 (2018)
5. P. L. and G. Bishop, Nitrogen transformation during sludge composting, Biocycle, 24
(1993)
6. G. F. Huang, J. W. C. Wong, Q. T. Wu, and B. B. Nagar, Effect of C/N on composting
of pig manure with sawdust, Waste Management, 24, 8 (2004)
7. P. S. Murthy and M. Madhava Naidu, Sustainable management of coffee industry by-
products and value addition—A review, Resour Conserv. Recycl. 66 (2012)
8. Mwazi, Evaluation of the effects of salinity on spinach (Beta vulgaris var. cicla) grown
in a hydroponic system along the coast of Namibia., Agricola, 20 (2010)
9. M. Jakubus, Estimation of phosphorus bioavailability from composted organic wastes,
Chemical Speciation & Bioavailability, 28, 1–4 (2016)
10. S. N. Jamaludin, A. Abdul Kadir, and N. W. Azhari, Study on NPK Performance in Food
Waste Composting by Using Agricultural Fermentation, MATEC Web of Conferences
103 (2017)
11. M. Lalremruati and A. S. Devi, Duration of Composting and Changes in Temperature,
pH and C/N Ratio during Composting: A Review, Agricultural Reviews (2021)
7
E3S Web of Conferences 437, 04003 (2023)
IConGEET2023
https://doi.org/10.1051/e3sconf/202343704003