One of the key ideas of this project centered upon our concept of greenness and sustainability. Cyanobacteria is a highly special organism in this sense. Due to its independence from sources of organic carbon and its ability of photosynthesis, its cultivation and growth must be properly taken care of. Before we proceed to more advanced concepts, we must begin by testing the cultivation of cyanobacteria in daily environments. In this context, we used fish tanks or jars, which can be easily found in many households, as incubators. Based on the location and different family conditions of our team members, we conducted initial family experiments to find out the effect of climate, temperature, light, and household humidity on cyanobacteria growth in the household.
We aim to find out the growth pattern of cyanobacteria in living conditions in multiple cities in China (Hangzhou, Guangzhou, and Shenzhen). The cyanobacteria were cultivated in fish tanks and Erlenmeyer flasks, with the volume of cyanobacteria proportional to the volume of the container, the fish tank was given a circulator pump considering its size. The fluid for cyanobacteria is the liquid cultural medium, in order to demonstrate and evaluate the contribution of photosynthesis on the self-sustainability of cyanobacteria. Records for the first module took 21 days starting from (27/11/2022), with pictures taken at 8 pm (GMT+8). Five days after the initial date (01/12/2022), the effect of cyanobacteria growth can be observed and is highly obvious. Twelve days later, the cyanobacteria level became so saturated that it was suspended in the water around it. By the end of the experiment, the water around the cyanobacteria is opaque and appears green. However, in certain samples tested in Hangzhou, which experienced temporal cold weather, cyanobacteria turned from green to brown or brick red, giving off a foul odor that implies the death of cyanobacteria. Moreover, We also noticed in some samples that the growth of cyanobacteria attached to the water pump seemed to be greener compared to the cyanobacteria in the tank.
Cyanobacteria is proven to be satisfying in its growth under appropriate living conditions, and it could achieve a satisfying level of concentration for further production and allow for sustained use. However, cyanobacteria growth is proven to be insufficient in certain conditions. The temperature has the most significant impact on cyanobacteria growth. And the pump of circulation is also vital to the growth of cyanobacteria. If the cyanobacteria concentration exceeds the sustainable level of the container, mass death occurs due to the deposit of cyanobacteria at the bottom of the tank, which deprives them of oxygen and sunlight. Another variable, sunlight, was also found to have an effect on the cyanobacteria.
Our first trial in tanks and jars showed cyanobacteria growth relies on a stable environment, which prompts us to create a device that helps with its cultivation and use. The desired apparatus is supposed to maintain a stable environment, provide artificial light and oxygen source, and allow for proper circulation. A bioreactor, or an apparatus with pumps and transparent tubes which cyanobacteria circulates within may be the solution to maintenance of a stable environment. The tube structure of the bioreactor makes it ideal since flowing water prevents cyanobacteria deposits in the bottom.
Two prototypes were organized, with one small-scale and one full-scale prototype. Both bioreactors had artificial sources of light and electric pumps, which allowed for the cyanobacteria to circulate and have enough light. The small-scale prototype analyzes the circulation and effectiveness of cyanobacteria in an enclosed environment with electric pumps and a combined source of illumination. It also tested the possibility of having an artistic design of the circulation system by incorporating the design of our logo. The large-scale model analyzed the performance of cyanobacteria in larger environments with a fully equipped circulation system (an air pump and a water pump) and an adjustable lighting system. The larger bioreactor is used to measure optical density values every day and to evaluate the growth of cyanobacteria. The algae were continuously observed in magnitudes of visual and biological analysis, and it was ensured that the algae finished one reproductive cycle inside.
Overall, the effects of both large- and small-scale bioreactors are proven to be satisfactory. Both bioreactors can work properly, as lighting and insulation provided by the tubing allow the inner condition to be maintained at an ideal level. The small-scale bioreactor appears to be green and illuminated with light, which indicates that artistic design can be achieved through the circulation system. The large-scale bioreactor, in the Comparison between the first few days of the observation (starting 03/10/2023), shows optical density levels growing exponentially, matching the expected rate of growth exhibited in module 1. However, shortcomings were also observed, as the two previous bioreactors are still aesthetically deficient, and do not blend well into daily use. Also, they lack a proper way to emit fragrances and adjust to different temperature conditions. However, it is expected that these shortcomings of the prototype bioreactor will be improved in our final concept.
In order to produce a new version of the bioreactor that blends well into daily use, our team designed two serials of the bioreactor that have a close resemblance to common large and small items in everyday life. The large bioreactor imitates flowing water sceneries that are common to public facilities and offices. The small bioreactor consists of a wide array of daily item that is correlated with scent. The combination of bioreactors, large and small, provides solutions to anxiety and stress by surrounding us with fragrances.
Based on the feedback of the two prototypes, we made a call for design among our team members. And we collected two amazing large bioreactor designs and a few small bioreactor designs.
This large bioreactor mimics the common flow water sceneries commonly found indoors, it can exist independently or be incorporated into walls and structures. A collection pool contains cyanobacteria, and water pumps bring cyanobacteria up a fountain pours down the cascading levels and pours back into the pool. This design can be applied in multiple sceneries, such as the public square, indoor library, or any crowded place to provide fresh and pleasant air to the public.
This large bioreactor takes inspiration from the flower basket on the roadside. It is composed of the circulation system, the lighting system, and the soil covering it. With the lighting system and the pumps on the side, the circulation system can be easily operated. Moreover, the main part of the reactor is packaged by the blanket with flowers growing on the top to make it blend in with the city decorations well. And with the blacket covering it, it can placed on the street where a large amount of sunlight is available. And because of its low cost by using wooden planks, the large reactor can be easily compacted into the city in large amounts. This design allows the reactor to function on the street effectively while blending in naturally, benefiting the citizens using its aroma and soothing outfits.
Small diffuser with solar panel. This small bioreactor was the idea of one of our team members and we found that there is a similar product online and adjusted it to be more suitable for our goals. It only had a small chamber for essential oil, and we made the inner space larger so it could be filled with cyanobacteria, and diffuse the aroma that is produced by the cyanobacteria we synthesized. In this case, it can produce fragrances constantly to create a pleasant smell, and can be more eco-friendly by using our product. It's also accommodated for carry-around and causal placement on desks, workbenches, and cars. The new version of the bioreactor overcame previous deficiencies as an exposed top and permeable exterior allow for the scent to escape and spread around without the cyanobacteria spilling.
We took the idea from the fish tank and took inspiration from the lab that cyanobacteria can also grow on a solid medium like agar plates. We further designed wind chimes that consist of a chain of small bottles filled with cyanobacteria. The small bottles were previously filled with the solid medium and the synthesized cyanobacteria were then planted in it. Then it can be hung under the light and allowed to grow. Even though it can be simple, it can provide stimulation to our three senses, eyes, nose, and ears, which can significantly relief stress.
A serials product of wearable devices. To make our product more suitable for daily use, we also designed a series of wearable devices so that people can wear them and enjoy the pleasing smell. Key chains, earrings, bracelets, fragrance brands, necklaces, and etc. All these products share a similarity of a fashion design and are able to constantly produce fragrances. We made some prototypes before it could proceed to the market.
Summary: the new version of the large bioreactors could successfully overcome the previous issues and provide an aesthetically and practically balanced solution to incorporating biologically generated fragrances into the mundane of daily life, adding scent and color that relieves stress. The new version of design considers the needs of both consumers and producers, creating the most effective product at the lowest costs and burden to the environment, which corresponds to our slogan: Spot greenness, smell happiness.
