1. Introduction
Traditional kelp drying methods (TKDM) have long depended on labor-intensive harvesting and inefficient drying methods. These methods require significant time and effort, leading to high labor costs and necessitating expansive physical spaces, ultimately hindering productivity. Additionally, inefficiencies in these processes have considerably limited the profitability of aquaculture operations while exacerbating their environmental footprint. The variability in product quality during harvesting, coupled with the high energy demands associated with drying, underscores the inherent limitations of conventional practices. These challenges highlight an urgent need for innovation within the industry.
Modern aquaculture faces the dual challenge of enhancing productivity and ensuring sustainability. Beyond its economic significance, kelp aquaculture plays a pivotal role in maintaining marine ecosystems by providing habitats for marine life and acting as a natural carbon sink. However, traditional methods are insufficient to fully realize this potential, especially in preserving the nutritional and elemental composition of seaweed products (García-Sartal et al. 2013). Workers endure physically demanding tasks, and operational inefficiencies restrict economic competitiveness and scalability (Hwang et al., 2007). To address these limitations, the adoption of automation technology has become essential. Automation not only reduces reliance on manual labor but also ensures consistent quality while simultaneously decreasing operational costs and environmental impact.
This study seeks to maximize productivity and minimize resource consumption by automating the entire kelp aquaculture process. Specifically, it involves the integrated development of an automated harvesting system (AHS), a sea-to-land transport system, and a vertical drying system. These innovations aim to enhance the efficiency of kelp aquaculture by reducing labor dependency, maintaining consistent product quality, and improving the overall stability and economic viability of the operations. By achieving these goals, the systems are expected to bolster the competitiveness of the aquaculture industry while simultaneously contributing to marine environmental conservation.
Furthermore, automation offers broader implications for the industry, extending its applicability to other types of seaweed farming and setting a benchmark for sustainable aquaculture practices. By addressing both productivity and sustainability, this study aims to provide a comprehensive framework for the future of kelp aquaculture, emphasizing the role of innovative technology in shaping a more resilient and eco-friendly industry (Yang et al., 2016).
2. Development Methodology
2.1 Development of the Automated Kelp Harvesting System
The automated kelp harvester was developed to simplify the harvesting process by automating vertical cutting and bundling operations. The system applied vertical cutters and drum-type attachment devices, optimized through structural analysis to enhance performance. This innovation significantly reduces the sway motion experienced in conventional harvest barges, thereby improving operational stability as shown in Fig. 1.
The harvester automates the cutting and bundling of kelp, dramatically shortening the harvesting process. In traditional manual operations, harvesting was time-intensive and led to increased worker fatigue, which negatively affected efficiency. By automating these processes, the harvester not only reduces operational time but also minimizes variability in product quality, ensuring consistency across harvested kelp.
To ensure the reliability of the Automated Harvesting System (AHS), extensive testing was conducted across multiple environmental conditions, including variations in wave height, current velocity, and kelp density. A prototype was initially developed and tested in a controlled marine environment before undergoing real-world trials. Structural stability analyses using finite element modeling (FEM) confirmed that the cutting and bundling mechanisms maintained consistent performance under dynamic marine conditions, taking into account wave-induced motion similar to barge course stability studies (Lee, 2018) .
Additionally, iterative improvements based on real-time sensor feedback allowed for enhanced cutting precision and reduced material loss. These validation steps ensured that the automated system effectively outperformed traditional manual methods in both efficiency and consistency.
Experimental results demonstrated that the automated system increased harvesting efficiency by 35%, improving the processing rate from approximately 20 kg/hour to 27 kg/hour. Additionally, structural improvements to the barge reduced sway motion by 15%, significantly enhancing operational stability (Lee et al., 2016). These findings served as critical data for the system's design and iterative improvements.
2.2 Design of the Sea to Land Transport System
To efficiently transport harvested kelp from sea to land processing facilities, a modular sea-to-land transport container system was developed. This system comprises prefabricated containers and multi-tier upright transport containers. Its structural stability was evaluated using simplified grillage analysis to ensure secure connections between modules, enabling safe transport under various marine conditions. Reinforcements were added to minimize damage from vibrations and shocks during transport.
Various prototypes were evaluated for stability and efficiency during transportation.
A total of three transport container prototypes were developed and tested under varying load conditions to ensure optimal structural stability. Simplified grillage analysis and impact simulations were performed to evaluate the integrity of the modular connections. Experimental drop tests and vibration analysis further validated that the system could withstand shocks and sudden impacts encountered during transport. By incorporating these validation steps, the final transport system was optimized to reduce damage rates while maintaining structural integrity under diverse environmental conditions.
The results confirmed that the container's design significantly reduced the risks of damage and contamination during transit. To prevent corrosion from seawater, the container's exterior was treated with a specialized coating. Additionally, the internal structure was optimized to prevent the compression of kelp and to ensure smooth airflow, preserving the quality of the kelp throughout the transportation process as shown in Fig. 2.
Various prototypes were evaluated for stability and efficiency during transportation. The results confirmed that the container's design significantly reduced the risks of damage and contamination during transit. To prevent corrosion from seawater, the container's exterior was treated with a specialized coating. Additionally, the internal structure was optimized to prevent the compression of kelp and to ensure smooth airflow, preserving the quality of the kelp throughout the transportation process. This internal configuration is illustrated in Fig. 3. which presents the detailed structure of the loading cart used during transport.
The container system minimized manual labor during transport, preventing quality degradation, reducing transport times, and improving worker safety. Its modular design enabled easy assembly and disassembly, allowing flexible adaptations to various marine conditions. This modular approach also contributed to a cost reduction of approximately 20%, enhancing the economic feasibility of kelp aquaculture. The primary objective was to efficiently transport harvested kelp from sea to land for prompt drying, and each module was designed to support this goal effectively.
To improve transport efficiency, the container was designed with a multi-tiered stacking system, enabling it to carry significantly larger quantities of kelp per trip. This design maximized space utilization, increasing transport capacity by approximately 1.5 times compared to conventional systems. Consequently, transportation costs were reduced, and the number of trips required was minimized (FAO, 2013).
Rigorous testing under various environmental conditions, including simulated wave heights and wind speeds, ensured the structural stability of the containers. These tests confirmed the durability of the containers against shocks and vibrations typically encountered during marine transport. Such design features played a crucial role in maintaining the quality of kelp and minimizing damage during transit.
According to transport efficiency data, the damage rate during transportation using the container system decreased significantly, from 15% in traditional methods to 5%. Additionally, the multi-tiered stacking structure of the containers enhanced transport efficiency, reducing the average transport time from 6 hours to 4 hours. This improvement resulted in a substantial reduction in overall logistics costs. The duct system within the container, designed for optimal ventilation, played a critical role in preserving the quality of kelp during transportation.
These improvements had a highly positive impact on both cost reduction and quality preservation, enabling aquaculture operators to deliver higher-quality products to the market. Furthermore, the automated transport system minimized the need for direct human intervention, ensuring worker safety and reducing the potential for human error during the transportation process.
2.3 Pilot Development of the Vertical Drying System
The vertical drying system was designed to address various inefficiencies inherent in traditional kelp drying methods. Traditional kelp drying methods required large spaces and prolonged drying times, posing significant limitations to productivity. In contrast, the vertical drying system utilizes a high-density, multi-tier stacking structure to maximize space utilization and enhance drying efficiency through natural convection. This innovation reduces spatial constraints and enables faster, more efficient drying processes.
During the initial stages of the study, extensive experiments were conducted to optimize the efficiency of the vertical drying system.
To validate the drying performance of the Vertical Drying System (VDS), extensive airflow simulations and thermal analysis were conducted. Computational Fluid Dynamics (CFD) models were utilized to assess airflow distribution and identify potential bottlenecks. Additionally, real-world drying tests were performed across different humidity and temperature conditions to refine the drying parameters. The data collected was used to fine-tune the drying system, ensuring consistent moisture reduction while minimizing energy consumption. These experiments played a crucial role in validating the system’s efficiency and long-term reliability.
Multiple variables, such as suspension conditions, stacking density, and spacer configurations, were tested to determine the optimal drying parameters. Key factors included the thickness of binding loops, the size of spacers, and the dimensions of transport containers. Based on these tests, the theoretical loading capacity was determined to be 68 sheets per container. However, under field conditions, a practical density of 50 sheets per container was found to be more appropriate. With eight transport containers fitting into each multi-tier upright system, a single upright system could accommodate 400 sheets of fresh kelp. By adjusting the drying process to achieve a moisture content of 15-20%, the system could produce 80.0 kg of dried kelp per batch as summarized in Table 1.
The vertical drying system was developed with the dual goals of reducing drying time and maximizing space efficiency. The design concept of the vertical drying container is shown in Fig. 4, highlighting its high-density stacking configuration and internal airflow layout. Unlike traditional horizontal methods, which require extensive space and lengthy drying periods, the vertical system prioritizes optimized space usage and enhanced drying performance. By leveraging natural convection to circulate air, the system reduces energy consumption while enabling uniform drying. Various structural designs and configurations were tested to optimize airflow, resulting in significant improvements in both drying time and product quality.
Experimental results demonstrated that the vertical drying system reduced drying time by approximately 40%, significantly contributing to increased productivity and improved product quality. While the traditional kelp drying method required an average of 48 hours, the introduction of the vertical system reduced drying time to 28 hours. This improvement not only enhanced productivity but also played a crucial role in minimizing quality variability during the drying process, enabling the production of uniform and high-quality products.
The shorter drying time accelerated the entire production process, leading to a substantial increase in overall production line efficiency.
Moreover, by utilizing natural convection, the system reduced energy consumption by 25% compared to traditional kelp drying methods, enabling an environmentally friendly aquaculture operation. The natural convection drying process eliminated the need for artificial air circulation devices, resulting in significant energy savings. This reduction in energy consumption contributed to the economic feasibility of aquaculture operations by lowering production costs, ultimately improving profitability for aquaculture farmers.
Another key feature of the vertical drying system is its high-density stacking design, which maximized space utilization. This design not only enhanced spatial efficiency but also ensured smooth airflow during the drying process. The stacking structure was optimized to facilitate even air circulation, preventing any deterioration in kelp quality as shown in Fig. 5. and Fig. 6.
Through experiments comparing various stacking configurations and densities, optimal conditions were identified, leading to significant improvements in productivity.
In addition, the design of the vertical drying system contributed to improving the working environment for operators. In traditional kelp drying methods, workers had to move across large spaces frequently to monitor the drying process.
In addition, the design of the vertical drying system contributed to improving the working environment for operators. In traditional kelp drying methods, workers had to move across large spaces frequently to monitor the drying process. However, the vertical drying system integrates automated monitoring devices, allowing real-time observation of the drying status. This advancement significantly reduced the physical demands on workers, creating a more efficient and ergonomic working environment. The reduction in worker fatigue translated into improved task performance and played a crucial role in enhancing the overall stability of the production process.
The implementation of the vertical drying system not only reduced drying time but also improved operational efficiency, maintained product quality, and decreased energy consumption. These combined benefits strengthened the competitiveness of aquaculture operations across multiple dimensions. Additionally, by utilizing data collected during the drying process to optimize operational parameters, the system lays the foundation for developing a smart drying system. This innovation is expected to enable the realization of sustainable marine aquaculture practices in the future.
3. Results and Discussions
3.1 Performance of the Automated Harvesting System
The automated harvesting system significantly improved operational speed while reducing dependence on manual labor, resulting in an approximately 35% increase in productivity. In traditional kelp drying methods, the processes of cutting and bundling kelp were labor-intensive, leading to high time consumption and increased worker fatigue. However, the introduction of the automated harvester mechanized these tasks, increasing work speed by approximately 35% and improving throughput from 20 kg per hour to 27 kg per hour as summarized in Table 2. In particular, the automated harvesting system minimized errors during the harvesting process and maintained consistency in operations, resulting in a quality deviation of less than 2% for the harvested kelp. In traditional kelp drying methods, the quality of the harvest often varied depending on the experience and skill level of the workers.
However, the automated harvesting system successfully overcame these limitations. Statistical analysis confirmed the significance of these improvements (p-value < 0.05), demonstrating that the introduction of the automated harvesting system contributed substantially to performance enhancement. This finding highlights the critical role of automation in reducing human error and ensuring consistency in product quality during the harvesting process.
Moreover, the automated harvesting system played a vital role in ensuring worker safety. In manual harvesting processes, workers were exposed to repetitive tasks in marine environments, increasing the risk of injury and musculoskeletal disorders. With the adoption of the automated system, workers were no longer required to perform physically demanding tasks during harvesting, significantly reducing the risk of injuries. As worker fatigue decreased, the quality of their performance improved, leading to an overall increase in productivity. The transition of workers to roles focused on monitoring and operating the system further enhanced workplace safety, marking a significant improvement in the working environment.
The improvements in worker safety extended beyond merely reducing the risk of injuries, leading to a qualitative enhancement of the work environment. In traditional kelp drying methods, the repetitive and physically demanding nature of the tasks caused high levels of worker fatigue, which in turn increased the likelihood of reduced work quality. However, with the implementation of the automated harvesting system, workers were relieved of significant physical strain and transitioned into more efficient roles. This shift not only improved worker satisfaction but also became a key factor in enhancing the overall operational efficiency of aquaculture.
The introduction of the automated harvesting system brought significant benefits not only in terms of efficiency but also in ensuring quality stability and improving worker welfare. Additionally, the structural stability of the system under wave-induced conditions was evaluated through simulation, and the time-dependent distribution of maximum stress is shown in Fig. 7, confirming its robustness in marine environments.
This automated harvesting system demonstrates the potential for broader application in other types of seaweed aquaculture, representing a critical technological advancement for the future competitiveness of the industry. Additionally, when integrated with data-driven smart aquaculture technologies, the system enables real-time monitoring and optimization of the harvesting process, paving the way for continuous improvements in overall process efficiency.
3.2 Efficiency of the Sea-to-Land Transport System
The sea-to-land transport system significantly improved transportation stability compared to traditional kelp drying methods, which are often limited by marine environmental factors such as wave height and current flow (Jeong et al., 2013) manual system products were highly susceptible to damage and contamination during transit. However, the adoption of the container system substantially mitigated these issues, reducing transit-related risks and enhancing overall efficiency. Improved transportation efficiency also shortened delivery times and reduced logistics costs. Grillage analysis of the system's structural stability confirmed the reliability and cost-effectiveness of its design as summarized in Table 3.
One of the key achievements of the container system was the increased level of automation in the transport process. Tasks that previously required extensive manual labor were replaced with automated systems, leading to reductions in labor costs and improvements in transport efficiency. Automated loading and unloading processes minimized the need for worker intervention, reducing human error and improving the consistency and reliability of transport operations. Furthermore, the multi-tier stacking structure enabled the transportation of larger quantities of kelp per trip, contributing to significant cost savings (Animal and Plant Quarantine Agency, 2012).
Transport efficiency data revealed that, following the implementation of the container system, damage rates decreased from 15% to 5%, while average transport time was reduced from 6 hours to 4 hours. To verify the statistical significance of these improvements, a paired t-test was conducted, confirming a statistically significant reduction in damage rates (p-value < 0.05) and transport time (p-value < 0.05), reinforcing the reliability of the proposed automation system, as summarized in Table 4. These improvements enhanced the economic feasibility of aquaculture operations as a whole. Additionally, the use of reusable modular designs minimized the need for packaging materials, reducing waste generation and lowering the environmental impact of the system. These outcomes played a vital role in improving the overall efficiency and sustainability of aquaculture.
In conclusion, the sea-to-land transport container system successfully enhanced productivity and efficiency while improving both the economic and environmental sustainability of aquaculture through automation and multi-tier stacking structures. This technology holds great potential for application to the transport of other types of seaweed, further increasing the efficiency of the marine aquaculture industry as a whole.
3.3 Performance of the Vertical Drying System
The vertical drying system reduced drying time by approximately 40% compared to traditional kelp drying methods. This was achieved through the efficient use of space enabled by the high-density stacking system and the application of natural convection for air circulation.
To verify the statistical significance of these improvements, multiple drying trials were conducted under controlled conditions. A repeated measures ANOVA test confirmed that the reductions in drying time (p-value < 0.05) and energy consumption (p-value < 0.05) were statistically significant. These findings reinforce the reliability and effectiveness of the proposed vertical drying system.
While the traditional kelp drying methods required large spaces and long drying times, the vertical system optimized spatial utilization, reducing drying time from 48 hours to 28 hours and significantly increasing productivity which are summarized in Table 5 as follows.
Natural convection played a critical role in reducing energy consumption. By eliminating the need for artificial air circulation devices, the system lowered energy usage by 25% compared to conventional methods, minimizing environmental impact. These reductions in energy consumption also contributed to improved economic feasibility by lowering operational costs and reducing carbon emissions.
From a quality management perspective, the vertical drying system delivered substantial improvements. The combination of high-density stacking and natural convection ensured uniform drying of the kelp, reducing quality variability and enabling consistent product quality for consumers. Furthermore, the integration of an automated drying monitoring system decreased worker labor intensity, improved workplace conditions, and enhanced overall efficiency and worker satisfaction.
This vertical drying system demonstrates strong potential for application to the drying of other seaweed varieties, offering broader benefits for the aquaculture industry. With its emphasis on energy efficiency and carbon emission reductions, this system represents a critical technological advancement for enhancing the sustainability and competitiveness of aquaculture.
4. Conclusions and Future Works
This study developed and implemented an integrated automation system for the harvesting, transportation, and drying processes in kelp aquaculture. By automating the entire kelp aquaculture process, the system aimed to enhance operational efficiency, maintain consistent product quality, and reduce resource consumption and costs. The adoption of automation significantly improved both the productivity and environmental sustainability of kelp aquaculture. These outcomes suggest that the system can be applied to other types of seaweed aquaculture, contributing to the efficient utilization of marine resources. Furthermore, the system represents a shift from labor-intensive and inefficient traditional methods to a more economical and eco-friendly production approach.
The automated harvesting system shortened the harvesting process and reduced the risk of worker injuries, playing a vital role in improving workplace safety. The efficient transport container system minimized damage and contamination risks during the sea-to-land transportation process while reducing costs and maintaining product quality. Additionally, the vertical drying system reduced drying time by approximately 40% compared to traditional horizontal methods and lowered energy consumption by 25%, enabling environmentally friendly production practices. These improvements collectively enhanced the economic and environmental sustainability of aquaculture operations as summarized in Table 6 and Table 7.
Future works should explore the application of this technology to large-scale seaweed aquaculture and investigate its integration with renewable energy sources to minimize environmental impact.
Furthermore, the continuous optimization of automated harvesting and drying systems through data collection and analysis is necessary. For example, real-time monitoring of temperature and humidity during the drying process could enable the development of a smart drying system that automatically adjusts drying conditions.
