Performance Evaluation of Compost of Windrow Turner Machine Using Agriculture Waste Materials

Abstract

Composting is the decomposition of organic matter in an aerobic environment. The windrow turner machine is used to turn the compost piles for efficient composting. It effectively addresses important issues such as managing crop leftovers and disposing of animal waste. This paper evaluates a comparison between mechanized (pile 1) and conventional (pile 2) compost-turning processes and the need for windrow turner machines to manage waste effectively and turn it into nutrient-dense material. This approach not only delivers a practical solution, it also points out the potential for a significant increase in soil fertility and agricultural sustainability. Five samples were taken from each pile at 10 feet intervals for chemical analysis. A total 13,768 kg of the compost yield was collected from pile one and 11,512 kg from pile 2. The study’s findings show that the machine turned a greater cation exchange capacity (CEC) value than the compost manually turned. Pile 1 was turned using a compost windrow turner machine, and pile 2 was turned manually. The CEC values in pile 1 varied from 21.23 meq/100 g dry weight to 68.87 meq/100 g dry weight after eight weeks, while the CEC values in pile 2 increased from 21.23 meq/100 g dry weight to 33.28 meq/100 g dry weight. The value of electrical conductivity (EC) in pile 1 increased from 1.98 ds/m to 11.34 ds/m, whereas in pile 2 it climbed from 1.98 ds/m to 7.86 ds/m after 8 weeks. The C/N ratio of pile 1 dropped to approximately 15 and the concentration of micronutrients increased during the composting process, which indicate mature composted material. The outcomes of this research contribute that mechanical composting emerges as a highly suitable method for efficiently managing the composting process, ensuring uniform decomposition, enhanced aeration, and the production of high-quality compost.

1. Introduction

Waste management (WM) is the most significant ecological concern in Pakistan. Proper municipal waste management is a critical concern in both rising and established countries across the world. Pakistan’s soils are deficient in organic matter (OM), which means that overall fertility is insufficient to boost agricultural productivity. This low OM is a result of high temperatures and little precipitation. Continuous crop output and insufficient replenishment have resulted in nutrient depletion in a large percentage of Pakistan’s soils. Agriculture acts as the principal revenue source for a large segment of the worldwide populace, especially in less developed and progressive regions. It is predominant global source of sustenance. A major issue within this industry is the considerable production of organic waste [1]. Multiple studies have indicated that waste generation rates are positively related to household consumption levels [2]. Recycling these wastes is essential for ecological security and revenue for agriculture. Our agricultural land is mostly made up of loess that have limited organic matter and essential nutrients [3]. Composting is a cost-effective approach to convert trash into a valuable product. So, composting is the way to solve this issue. Composting is the process of converting garbage into nutrient-rich material.

Composting is a natural process of organic matter decomposition, transforming waste materials into nutrient-rich humus that can improve soil health and plant growth. The process involves various biological, chemical, and physical transformations, driven by microbial activity. Traditionally, composting has been carried out through manual methods, such as static pile composting and passive aeration. However, the introduction of mechanized composting has significantly enhanced the efficiency and scalability of compost production [4]. This introduction explores both conventional and mechanized composting processes, highlighting their principles, advantages, and challenges. Mechanized composting involves the use of machinery to automate and optimize various aspects of the composting process, such as aeration, turning, and temperature control. This approach can significantly enhance the efficiency, scalability, and consistency of compost production. These machines are designed to turn and aerate windrows mechanically. They ensure uniform mixing and oxygen distribution, which accelerates decomposition and improves compost quality [5]. Windrow turners can handle large volumes of organic waste, making them suitable for commercial-scale composting operations.

Compost increases soil nutrient levels and water retention capability. It also reduces smells, flies, and other vector concerns and successfully eliminates weed seeds and diseases [6]. Compost serves as a highly effective substitute for enhancing soil organic carbon levels in developed countries [5]. Because of their high organic content, composts have long been used as soil supplements. Composting improves manure management by reducing bulk and mass [7]. Vast amounts of tree leaves, grass clippings, plant stems, vines, weeds, branches, and twigs are routinely incinerated [8]. This organic material has the capability to improve soil nutrient levels and produce significant increases in crop yields by decomposing it into the soil [9]. Compost heaps, especially those in windrows, can be aerated and mixed using various devices. Therefore, the purpose of this study was to give local farmers a way to satisfy the nation’s food needs through mechanization.

2. Material and Methods

2.1. Study Area

The city Multan, where we conducted our experiment, is Pakistan’s fifth biggest city. It is located between 29′–22′ and 30′–45′ North latitude, and 71′–4′ and 72′–4′55 East longitude. This city is located in a bend produced by the formation of five rivers. The average rainfall is 127 mm [9]. The place where we conducted our experiments had all the things we needed to make compost piles and make sure our machines worked well. This place was the solid waste management (SWM) site of the Muhammad Nawaz Shareef University of Agriculture Multan (MNSUAM). Being so close to the department made it easy to manage everything and turn waste into useful compost. This made things quick and easy, so we could fix any problems or make changes as soon as we needed to while making compost. Composting is like making plant nutrients, and we needed three main things for it, which are brown stuff, green stuff, and water. The brown stuff is things like dried leaves, branches, and twigs. The green stuff is grass clippings, veggie scraps, fruit pits, and coffee grounds. We acquired the green stuff from the university’s gardens and fields. Compost windrow heaps can be aerated and rotated using various machinery equipped with revolving drums. The latter devices are not effective on all materials [10].

2.2. Compost Windrow Turner Machine

The compost windrow turner features a rotor with a diameter of 170 mm and a length of 2970 mm. This is assembled from a mild steel sheet with a thickness of 9 mm. The rotor is equipped with a total of 38 turning blades, each made from MS sheet. Additionally, the machine features a 500 L water tank for effective water application. These specifications contribute to the machine’s efficiency and functionality in composting operations, as shown in Figure 1.

2.3. Compost Process and Data Collection

Composting is a dynamic process in which microorganisms like bacteria and fungi break down organic waste. This activity produces heat as a byproduct. The heat generated comes from the metabolic activities of microorganisms. Composting releases CO₂ and water vapor into the atmosphere. As composting occurs, the volume and mass of the original components decrease. This decline is mostly due to the loss of carbon in the form of CO₂ and the release of water vapor. A windrow is formed in the same manner as a static pile is formed, but the shape of windrows is usually longer [11]. Composting process parameters like temperature control and odor control are also affected by the used strategy [12], as shown in Figure 2. Windrow composting is the process of arranging a variety of raw materials in long heaps called windrows that are turned on a regular basis. Windrow composting is the most utilized method on large farms and large-scale composting plants. For our research, we chose the windrow piles system. We wanted to explore how utilizing a unique pierce of equipment known as a windrow turner effect the nutrients, electrical conductivity (EC), and cation exchange capacity (CEC) in compost. For the experiment, two big piles of compost were prepared by layering different types of organic materials to collect the data. The greens, rich in nitrogen, encompass vegetable and fruit scraps, grass clippings, manure from herbivores, and green plant trimmings. These materials provide the necessary nutrients and moisture for microbial activity. Browns, rich in carbon, include dry leaves, straw, hay, wood chips, shredded cardboard, paper, corn stalks, and brown plant trimmings. Each pile was up to 50 feet long, 8 feet wide, and 4 feet tall. The data were collected from five stages at 10 feet from the start of the each pile. A tractor was operated to crush the branches of trees. This balance is vital for creating a successful and effective composting environment. Microbes consume oxygen, while digesting organic waste. The decomposition of this organic waste can be accelerated if optimal conditions are maintained, such as a PH between 6 and 9 and moisture between 40 and 60, while the optimum range is 65–85% [13]. We utilized a windrow turner machine with 12 nozzles for spraying water on the pile to keep the moisture level at 40–60%. Molasses were also used to boost microbial activity in the piles. This helped the crushed materials to break down with the help of air. After one week, we turned pile 1 with the machine and pile 2 manually to see the resulting variations in the machine-turned and manually turned piles, and we kept doing that to make the compost better. Regular turning improves the flow of air through the material [14]. Turning is extremely helpful for the activity of microorganisms in windrow piles. It speeds up the rate of decomposition. A 45 hp tractor and a windrow turner were used one time per week to turn pile 1, and the activities are shown in Figure 3, Figure 4, Figure 5 and Figure 6.

The properties of the materials are given below in

Table 1. Properties of organic waste used in compost.

Organic Waste Use	Animal Manure	Rice Residue	Sewage Sludge
Total Nitrogen %	2.21	0.87	2.43
Total Organic Carbon%	38.76	42.34	41.58
C/N Ratio	17.53	48.66	17.11
Total Phosphorus %	6.4	0.58	0.89
Total Potassium %	0.97	0.35	0.68
Bulk Density kg/m3	1043.6	68.21	398.25
Moisture Content %	78.12	4.67	3.91

.

Data were collected from five locations within each compost pile to ensure specified standards like pH levels ranging from 5.5 to 9.0 and moisture content maintained between 40% and 65%. A minimum temperature of 62 °C was established for pathogen control during the composting process [15]. Throughout the composting period, samples were extracted every two weeks up to the 8th week from a depth of 2 feet in each pile. A sample weighing 200 g was collected from both piles, resulting in five samples for each test. The assessment of changes in CEC (cation exchange capacity) and EC (electrical conductivity) levels in each pile was conducted by obtaining five samples at intervals of 2, 4, 6, and 8 weeks.

Compost samples were obtained from the windrows, and the cation exchange capacity (CEC) was determined through a series of steps. Initially, 200 mg of compost sample was placed in a flask, followed by a thorough washing with 0.05 N HCL solution. Subsequently, the sample underwent an additional wash with distilled water to eliminate any residual traces of HCL.A solution of 1 N Ba(OAc)₂ was prepared, and its pH was adjusted to 7. This Ba(OAc)₂ solution was added to the flask containing the compost sample, and the mixture was left to stand overnight. Afterward, the sample was filtered, and a small quantity of Ba(OAc)₂ was introduced. The prepared sample was subjected to titration with 0.05 N NaOH solution utilizing a potentiometer. The measurement of protons released during the titration process provided the cation exchange capacity of the sample [16]. Electrical conductivity was measured using a (1:2.5) compost: water suspension with Xylem Analytics, Cairo, Egypt [17]. A thermocouple thermometer was used to measure the temperature in each compost pile, as well as the ambient air.

2.4. Statistical Analysis

To analyze the data, we first calculated the standard deviation (SD) using SPSS (IBM SPSS Statistics 29) to determine the degree of variation or dispersion within the dataset. The SD was computed for each variable of interest, providing a measure of the spread of data points around the mean. Subsequently, we conducted an independent samples t-test to compare the means of [two groups/conditions]. The t-test was performed to assess whether there were statistically significant differences between the means of the two groups. The test was conducted with a confidence interval of 95%, and the significance level (α) was set at 0.05. The t-test results, including the t-value, degrees of freedom (df), and p-value, were reported to determine the presence of any significant differences between the groups.

3. Results and Discussions

3.1. Compost Yield Data

The total compost yield was measured for two different compost piles, with pile 1 producing 13,768 kg and pile 2 yielding 11,512 kg. Turning the compost by machine increased compost yield 19.5% more than manual turning. This significant difference in compost yield between the two piles reflects the variations observed in their respective temperature profiles. These findings suggest that optimizing the temperature conditions during composting can significantly impact the overall yield [18]. Understanding and controlling the factors that influence temperature can help improve composting efficiency, leading to higher yields and better-quality compost.

3.2. Cation Exchange Capacity (CEC) Results

Cation exchange capacity (CEC) is a crucial property of compost that determines its ability to retain and exchange essential plant nutrients. The use of compost windrow turner machines during the composting process can significantly affect the CEC of the final compost product. This literature review examines recent studies that investigate the impact of compost windrow turner machines on CEC [19]. The decomposition of organic matter such as plant residues and manure is closely linked to CEC. Consequently, measuring CEC is valuable for assessing compost maturity.

Table 2. Variation in cation exchange capacity during the process.

Time Period	Cation Exchange Capacity (meq/100 g)
	Pile 1 (Mechanized Turning) *	Pile 2 (Manual Turning)
0	21.23 ± 1.01	21.23 ± 1.01
2	38.56 ± 1.13	23.17 ± 0.54
4	49.63 ± 0.52	28.86 ± 1.20
6	57.37 ± 0.96	31.16 ± 0.75
8	68.87 ± 0.85	33.28 ± 0.82

* Impact of a rotational speed of 300–350 RPM, forward velocity of 4 km/h and the implementation of convex-shaped turning blades on a turned pile.

show CEC results for piles 1 and 2. The CEC profiles of all heaps gradually increased during composting.

In the manually turned pile 2, CEC values rose from 21.23 meq/100 g dry weight initially to 33.28 meq/100 g dry weight after 8 weeks. For pile 1, where a windrow turner machine was employed, CEC values increased from 21.23 meq/100 g dry weight initially to 68.87 meq/100 g dry weight after 8 weeks. The t-test for CEC showed a statistically significant difference between the two piles (t = 2.31, p = 0.049). The significant increase in CEC values in pile 1 compost compared to pile 2 compost can be attributed to the frequency of turning and use of a turner machine. Several researchers have noted that CEC serves as an indicator of compost maturity. They suggest that the minimum CEC value required for acceptable maturity is higher than 60 meq/100 g [20]. A recent study by Waqas et al. 2023 [21] highlights the importance of aeration in enhancing microbial activity during composting. The use of compost windrow turner machines improves aeration, creating optimal conditions for aerobic microorganisms. These microorganisms break down organic matter more efficiently, leading to the formation of humic substances that contribute to a higher CEC. The use of compost windrow turner machines positively impacts the cation exchange capacity of compost by ensuring optimal aeration, temperature regulation, moisture management, and homogeneity. These factors collectively enhance microbial activity and humus formation, leading to a higher CEC in the final compost product. The recent literature supports the effectiveness of windrow turner machines in producing high-quality compost with superior nutrient retention capabilities, which benefit soil health and plant growth.

3.3. Results for Electrical Conductivity and Carbon to Nitrogen Ratio

Electrical conductivity (EC) and the carbon to nitrogen (C/N) ratio are critical parameters in the composting process. EC measures the total concentration of soluble salts in compost, which affects nutrient availability and potential toxicity to plants. The C/N ratio indicates the balance of carbon and nitrogen, influencing microbial activity and the composting process’s efficiency. This literature review examines recent studies on the effects of compost turning, particularly using windrow turner machines, on EC and the C/N ratio. The variation in EC indicate the transformation of organic waste and the removal of phytotoxic chemicals during composting. EC values indicate the availability of nutrients in compost. Larger EC values may suggest larger concentrations of nutrients such as nitrogen, phosphorus, and potassium, which are required for plant development. A summary of the windrow turner machine’s effect on the compost pile’s electrical conductivity is presented in

Table 3. Variation in electrical conductivity during the composting process.

Time Period	Electrical Conductivity (ds/m)
	Pile 1 (Mechanized Turning) *	Pile 2 (Manual Turning)
0	1.98 ± 0.15	1.98 ± 0.15
2	3.86 ± 0.25	2.46 ± 0.11
4	5.78 ± 0.33	4.86 ± 0.30
6	8.88 ± 0.30	5.12 ± 0.13
8	11.34 ± 0.47	7.86 ± 0.36

* Impacts of rotational speed of 300–350 rpm of rotor, 4 km/h forward speed of tractor, and convex-shaped rotating blades on pile 1.

. Comparative results of mechanical and manual pile turning are shown in Table 3. This indicates how electrical conductivity changes over time in both circumstances and shows a more comprehensive illustration of the data.

The increased electrical conductivity (EC) of composted materials might be attributed to the abundance of ammonia and other nutritional ions generated during the fast decomposition of organic waste. Excessive salt in compost can reduce microbial activity and plant development. EC measurements are useful in determining the salt content of compost.

These findings point out the window turner machine’s strong effect on the electrical conductivity (EC) of compost, offering insight into the dynamic changes that occur during the composting process. The t-test for EC revealed statistically no significant difference between the two piles (t = 0.96, p = 0.365). Due to the adoption of the windrow turner machine, the electrical conductivity increased for pile 1 significantly. The increase in electrical conductivity from 1.98 to 11.34 ds/m shows the machine’s efficiency in enhancing the process of composting. This significant increase suggests that the turner machine significantly supported the acceleration of microbial activity and the breakdown of organic materials, resulting in a more enriched compost production. Meanwhile, the electrical conductivity increased from 1.98 ds/m to 7.86 ds/m in the human-turned pile after a period of 8 weeks, representing that the absence of a turner machine resulted in a minor increase in electrical conductivity as compared to the machine-turned pile. This difference highlights the windrow turner machine’s significance in promoting more favorable microbial activity and improving composting conditions.

Compost’s C/N ratio drops as the piling process advances. In the beginning, the components in a compost pile have a high C/N ratio, which means there is more carbon than nitrogen. As microbes degrade organic materials, they utilize carbon for energy, potentially lowering the C/N ratio over time. The t-test for C/N indicated statistically no significant difference between two piles (t = −0.77, p = 0.464). This mechanism is significant, because a balanced C/N ratio encourages effective breakdown and nutrient availability for plants. The composting process decreases organic carbon, while increasing total nitrogen, resulting in a narrow C/N ratio.

Table 4. Variation in carbon to nitrogen ratio during the composting process.

Time Period	Pile 1 (Mechanized Turning)			Pile 2 (Manual Turning)
	%C	%N	C/N Ratio	%C	%N	C/N Ratio
0	43.53 ± 0.83	1.38 ± 0.12	31.56 ± 7.18	43.53 ± 0.52	1.38 ± 0.12	31.56 ± 4.49
2	39.34 ± 81	1.56 ± 0.14	25.23 ± 5.98	43.14 ± 0.32	1.52 ± 0.17	28.34 ± 1.84
4	38.48 ± 69	1.71 ± 0.12	22.45 ± 5.56	42.99 ± 0.51	1.66 ± 0.21	25.89 ± 2.46
6	36.96 ± 0.45	2.09 ± 0.50	17.67 ± 0.91	41.36 ± 0.60	1.92 ± 0.17	21.54 ± 3.46
8	34.34 ± 0.93	2.27 ± 0.48	15.12 ± 1.94	40.32 ± 0.70	2.14 ± 0.25	18.87 ± 2.82

shows a considerable drop in C/N ratio from 31.56 at the commencement of composting to 18.87 after 8 weeks for manually turned compost and 15.12 for machine-turned compost, as shown Table 4. Recent research by Patil et al. (2019) investigates the effects of turning frequency on EC during composting [22]. The study found that regular turning with a windrow turner machine helps to evenly distribute salts within the compost pile, preventing localized high concentrations. This even distribution leads to a more stable EC, which is beneficial for the final compost quality. A study by Zhang et al. (2020) examined the optimal C/N ratio for high-quality compost production [23]. The researchers found that starting with a C/N ratio of around 30:1 and using a windrow turner machine to regularly mix the pile helps achieve a final C/N ratio between 15:1 and 20:1, which is ideal for nutrient availability and compost stability. The literature highlights the significant impact of compost turning, particularly using windrow turner machines, on electrical conductivity and the carbon to nitrogen ratio. Regular turning enhances microbial activity, promotes an even distribution of salts, and accelerates the breakdown of carbon-rich materials, leading to stable EC levels and optimal C/N ratios. These findings underscore the importance of using windrow turner machines for producing high-quality compost with a balanced nutrient content and minimized phytotoxicity risks.

3.4. Results for Variation in Micronutrients during Composting Process

Plants require micronutrients in modest amounts, including iron, cobalt, chromium, iodine, copper, zinc, and molybdenum. Micronutrient deficiency might hinder plant growth and development as shown in Figure 7. They can help plants absorb and transfer nitrogen, phosphorus, and potassium. Iron is essential for chlorophyll synthesis and photosynthesis. Iron deficiency in plants affects young leaves by causing yellowing between the veins. Magnesium is crucial for enzyme activation, germination, and crop development. Zinc is essential for early development phases and balancing plant hormones. The growth of roots, seeds, and fruits also depends upon zinc. Micronutrient deficiencies can negatively impact plant output, quality, and the health of animals and people.

During the composting process, the concentration of micronutrient is enhanced. As can be seen in Figure 8, the concentration of manganese, copper, zinc, and iron in the mechanized-turn pile increased more as compared to the manually turned pile. The t-test for micronutrients presented statistically no significant difference between the two piles (t = −0.67, p = 0.267). The concentration of manganese, copper, zinc, and iron increases from 33.00, 22.23, 53.48, 112.53 to 213.67, 61.83, 198.37, 596.42 ppm, respectively, in pile 1, as shown in Figure 8. Micronutrients, including essential trace elements such as iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), and boron (B), play a vital role in plant growth and soil health. The composting process can significantly influence the availability and concentration of these micronutrients in the final compost product. This literature review examines recent studies on the variation in micronutrients during composting and discusses the factors influencing these changes.

A study by Kebibeche et al. (2019) investigated the release of micronutrients during the decomposition of organic matter in composting [24]. The study found that as organic matter breaks down, micronutrients bound within the organic material are released into the compost matrix. The availability of these micronutrients increases, making them more accessible to plants when the compost is applied to soil. Compost enriched with bioavailable micronutrients can significantly improve soil fertility and plant health. The slow-release nature of micronutrients in stabilized compost ensures a sustained supply of these essential elements to plants, reducing the need for synthetic fertilizers and enhancing soil microbial activity.

3.5. Discussion and Results of Temperature Variation

The temperature of compost pile 1 and pile 2 was monitored over a series of time points (from 1 to 56 days). The mean temperatures at each time point were reported, along with their standard deviations, which reflect the variability of temperature within each pile across multiple replications. A statistical analysis was conducted to determine if there was a significant difference in the temperature data between the two compost piles. First, the normality of the data was assessed using the Shapiro–Wilk test. The results indicated that the temperature data for both compost pile 1 (p = 0.886) and compost pile 2 (p = 0.249) were approximately normally distributed, as the p-values were greater than the significance level of 0.05. Following this, Levene’s test for homogeneity of variances was performed to evaluate whether the variances of the two groups were equal. The p-value from Levene’s test (p = 0.434) suggested that the variances between the two compost piles were indeed equal. An independent t-test was conducted as per set assumptions to compare the mean temperatures of the two compost piles. The results revealed a statistically significant difference between the two groups (t = −2.727, p = 0.011), indicating that the temperatures in compost pile 1 and compost pile 2 were not the same. This difference might be attributed to variations in compost composition, microbial activity, or other environmental factors affecting the piles. When microorganisms break down the composting elements, the temperature of the compost piles increases [25]. The process of composting starts with a mesophilic stage during which the organic ingredients are broken down by microbes. The temperature of pile 1 was 36 degrees Celsius at first, but as the decomposition process intensified, it began to rise. A too-high temperature is detrimental to the action of microbes. The temperature increased to 51 degrees after the fourth day of composting. The temperature of the compost heap rises fast as microbial populations develop and the decomposition of complex organic molecules accelerates. The thermophilic stage defined by temperatures ranging from 55 to 60 °C (131 to 140 °F) is critical for composting success

The temperatures ranged from 36 °C to 65 °C, with standard deviations varying between 2 °C and 4 °C. For instance, at day 1, the mean temperature was 36 °C with a standard deviation of 2 °C, indicating that the temperatures recorded were generally close to this mean, showing low variability. However, at day 12, the temperature was 61 °C with a standard deviation of 4 °C, suggesting slightly greater variability in the temperature readings at this point. Composting material temperatures rise rapidly to reach 55 to 60 °C, and then remain at this thermophilic level for several days [26]. The temperature in pile 1 climbed to 62 degrees on the twentieth day of composting and dropped to 38 degrees on the sixtieth day, as shown in Figure 9. The third phase is the cooling phase, during which temperatures return to normal and the compost stabilizes [19]. In order to sustain the proper temperature for microbial activity, we employ a windrow turner machine. The breakdown in the pile is shown by temperature fluctuation.

The temperature of pile 2 started off at 37 degrees Celsius, but as the decomposition process intensified, the temperature started to rise, as shown in the Figure 9. The temperatures ranged from 37 °C to 74 °C, with standard deviations between 2 °C and 4 °C. At day 1, the temperature was 37 °C with a standard deviation of 3 °C, similar to pile 1, indicating low variability at the start of the process. As the composting progressed, the temperature at day 28 reached 71 °C with a standard deviation of 4 °C, reflecting some variability but generally stable conditions. A too-high temperature is detrimental to the action of microbes. Temperature management is critical in composting. Temperatures between 45 and 55 °C provide the best degradation rates, whereas temperatures over 55 °C maximize pathogen decrease [23]. Excessive temperatures in compost can kill useful microbes, particularly those that break down organic materials. Extremely high temperatures can also kill heat-sensitive species and cause nitrogen loss via volatilization. The temperature climbed to 72 on the twentieth day of composting and fell to 57 on the sixtieth day. A temperature rise of 72 degrees indicates poor composting, because the temperature is just too high. This demonstrates that the temperature in pile 1 remains at an appropriate level due to the mechanized turning of the pile, as opposed to hand turning. Temperature variation is a critical aspect of the composting process, influencing microbial activity, organic matter decomposition, and the overall quality of the compost. The use of compost turning, especially with windrow turner machines, plays a significant role in managing and optimizing these temperature variations. This literature review examines recent studies on temperature variation during the compost-turning process and discusses its implications for compost quality and microbial dynamics. A study by Huynh et al. (2023) [26] discussed the enhanced decomposition of organic matter due to optimized temperature management through turning. Consistent high temperatures accelerate the breakdown of complex organic compounds into simpler substances, leading to a more mature and stable compost product. Effective temperature management through compost turning enhances the quality of the final compost product. The benefits include improved pathogen reduction, accelerated organic matter decomposition, and the production of stable, mature compost with higher nutrient availability. These factors contribute to better soil health and plant growth when the compost is applied.

The composting process involves several stages, each characterized by different temperature ranges and microbial activities. Figure 9 represents a detailed breakdown of the composting process for temperature variations. The mesophilic phase (30–40 °C) lasts a few days to a week. During this initial phase, mesophilic microorganisms break down the readily degradable organic matter. The temperature of the compost pile rises from ambient levels (typically 30–35 °C) to around 40 °C, with rapid microbial activity and the decomposition of easily degradable materials producing heat. In the provided graph, the temperature variations in the compost piles can be interpreted as follows. During days 1–4, the compost piles are in the initial mesophilic phase, with temperatures rising from ambient levels to around 45 °C. During days 4–16 (compost pile 1) and days 4–24 (compost pile 2), the piles enter the thermophilic phase, with temperatures peaking at around 65–70 °C, indicating intense microbial activity and rapid decomposition. During days 16–36 (compost pile 1) and days 24–36 (compost pile 2), the piles transition into the cooling phase, with temperatures fluctuating but gradually declining. During days 36–56, the piles enter the maturation phase, with temperatures stabilizing around 45–55 °C, indicating the compost is curing and becoming stable.

The thermophilic phase (40–70 °C) lasts several days to weeks. As the temperature exceeds 40 °C, thermophilic microorganisms become active, accelerating the breakdown of more complex organic materials. The temperature can rise to 70 °C or higher, typically peaking between 60–70 °C. Intense microbial activity occurs, leading to the breakdown of proteins, fats, and complex carbohydrates, with pathogens and weed seeds also being destroyed at these high temperatures. This phase often corresponds to the highest temperatures observed in compost piles. The cooling phase (40–50 °C) lasts several weeks. As the easily degradable materials are consumed, microbial activity decreases, and the temperature begins to decline. The temperature gradually drops from the thermophilic range to around 40–50 °C. Decomposition continues at a slower rate, and more-resistant organic materials are broken down. The maturation phase (35–40 °C) lasts several weeks to months. The compost enters this final phase, where mesophilic microorganisms become active again. The temperature stabilizes closer to ambient levels, around 35–40 °C. The compost matures, and humus-like substances are formed. This phase ensures the compost is stable and safe for use, with no phytotoxic compounds. These results highlight the critical role that temperature plays in the composting process. Higher temperatures in pile 1 likely facilitated more efficient microbial activity and decomposition, leading to a higher yield. This underscores the importance of monitoring and optimizing temperature conditions to enhance compost production. Future efforts to manage composting processes should focus on maintaining optimal temperature ranges, to maximize the yield and improve the quality of the final compost product.

Regular monitoring and turning of the compost piles help maintain optimal temperatures and ensure uniform decomposition. Adequate moisture and oxygen levels are crucial for maintaining microbial activity and preventing anaerobic conditions. Well-managed composting results in a stable, mature product rich in humus, beneficial microorganisms, and nutrients, suitable for improving soil health and fertility.

4. Conclusions

Mechanized composting means using modern machinery and technology to speed up the fermentation process, to prepare efficient compost. Compared to conventional composting techniques, the robotic process produces high-quality, nutrient-rich compost. This approach establishes a controlled environment in which parameters like temperature, moisture, and aeration are continuously monitored and encouraging the development of the beneficial bacteria required for effective decomposition. Mechanized composting produces nutrient-dense compost with higher quantities of vital nutrients, which contribute to increased soil fertility and stronger plant development. The size of the particles of compost material decreases with turning operations when we use a turner machine on a pile at a turning speed of 300–350 rpm. The cation exchange capacity of pile 1 increased from 21.23 meq/100 g to 68.87 meq/100 g and its electrical conductivity from 1.98 ds/m to 11.34 ds/m. On the other hand, the compost produced without mechanical means is immature, since its cation exchange capacity value is 33.28 meq/100 g, which is considered immature. A 72-degree temperature rise in pile 2 suggests inadequate composting, since the temperature is just too high. This illustrates that the temperature in pile 1 remains suitable due to the pile’s mechanical turning rather than manual turning. In pile 1, the temperature stays just right, because we use machines to turn the compost instead of doing it by hand. After 8 weeks of evaluation, the pile 1 C/N ratio fell to around 15, suggesting mature composted material. Similarly, the concentration of micronutrients increased in the mechanized-turning pile. In conclusion, this study demonstrated a significant difference in both temperature profiles and compost yields between the two compost piles. Compost pile 1, which maintained consistently higher temperatures, produced a significantly greater yield of 13,768 kg compared to the 11,512 kg yielded by compost pile 2. The statistical analysis confirmed that the temperature differences between the piles were significant, likely influencing the composting efficiency and resulting yield. The compost windrow turner machine ensures that the composting process produces high-quality compost at the end by maintaining equilibrium. In general, mechanical composting is a waste management technique that is sustainable and produces valuable resources for both agricultural productivity and soil health.