Background

A majority of essential oils currently on the market are extracted using one of two methods: hydro-distillation or steam extraction. While these techniques are widely used, they have several significant downsides. For instance, both methods often result in limited yield that not all valuable compounds from the plant material are extracted. Additionally, there is a loss of volatile compounds during the process, which can compromise the quality and therapeutic properties of the oils. The prolonged extraction duration can also hinder production efficiency. Finally, concerns about hazardous solvent residues can pose safety risks for consumers. These limitations highlight the need for more efficient and safer extraction methods in the essential oil industry.


Objectives

Our objective is to design an efficient distillation apparatus that enhances the yield of essential oil production while adhering to the two previously mentioned methods. By integrating simple extraction procedures, we aim to optimize the distillation process for users, ensuring that more essence is extracted from plant materials compared to traditional methods while using a compact device. In addition to improving yield, our apparatus is designed to promote the recycling of disposed plant materials, allowing them to be repurposed for essential oil extraction. This not only reduces waste but also contributes to a more environmentally friendly approach to essential oil production. By designing a domestic hardware for citizens, individuals are allowed to utilize the discarded part of the plant for essential oil extraction on their own, maximizing resource efficiency and minimizing negative environmental impact, aligning our project with sustainability goals.


Phase I

Initially, our hardware components were designed to be mounted onto a mobile kettle. We replaced the kettle’s cover with our 3D-printed parts for essence condensation. During extraction, steam passes through the tube and condenses on top, allowing the extract to drop into the collector below. Our components were integrated with the mobile kettle, equipped with temperature and time controls, as shown in Figure 1.

Figure 1. Sketch of hardware during initial phase

In the early development phase, we constructed the components using 3D printing. Parts in three different heights were created, as shown in Figure 2, to identify the optimal height for condensation. Each design was tested for extracting citrus peel essence. To evaluate efficiency, we compared extract volumes from each height variation in a centrifuge tube. This systematic approach helped us determine the height that yielded the most effective condensation, guiding us toward maximizing extraction efficiency.

Figure 2. 3D model of components in three heights
Figure 3. Diagram of components

Following the initial testing phase, the component with a height of 5 cm emerged as the most effective configuration for condensation. This design facilitated the efficient condensation of steam at the uppermost section, thereby maximizing the yield of collected essence. It achieved optimal condensation, resulting in a higher volume of extract compared to the other models evaluated. Conversely, the components in the height of 10 cm and 15 cm exhibited significantly longer extraction time due to the extended distance the steam had to traverse before condensing. This delay adversely affected their overall efficiency, culminating in the collection of less than 1 milliliter of essence. These findings unequivocally demonstrate that the 5 cm apparatus is superior in achieving optimal extraction outcomes.

Figure 4. Built components of phase I mounted on mobile kettle
Figure 5. Results of extraction using components of phase I

Phase II

To further enhance the volume of essence extracted, the incorporation of a condensation tube is anticipated during the extraction process. This addition is expected to streamline the condensation mechanism and increase efficiency. Therefore, During the second phase, the hardware is redesigned to simulate the function of a condensation tube. To achieve this approach, we developed a new hardware model as shown in Figure 6, the redesigned version allows various containers to be fitted in. In addition, ice can be placed in the container, accelerating the condensation of steam and enhancing the scent.

Figure 6. redesigned hardware in 3D
Figure 7. Lateral view of phase II model
Figure 8. Vertical view of phase II model

After testing out the redesigned hardware using citrus peels, the volume of extracted essence increased significantly compared to the previous model. The volume of extracted essence increased to 2 mililitres after 15 minutes of extraction, while less than 1 milimeter of essence was extracted using the previous model within the same time.

Photos of testing the redesigned model using citrus peels:

Built model of phase II
Testing of the redesigned model
The collected essence of citrus peels
Volume of essence collected by phase II model

Future Development

Furthermore, in collaboration with hotels, our hardware is designed for use in hotel rooms to provide customizable scents. Users simply select a ready-made capsule of plant material to insert into the device, allowing for fragrance enhancement in their rooms. Additionally, our hardware is compact, making it suitable for domestic use. This design enables individuals to utilize discarded plant materials for essence extraction in their homes.