On November 12, 2014, Toshiba first disclosed to the news media the Yokosuka Toshiba Clean Room Farm, which was launched on September 30th. The plant factory uses an idle factory equipped with a clean room to produce green leafy vegetables such as vegetables and sauerkraut in a state close to aseptic. The operating rate is only about 25%, but Toshiba said, "It will improve the proficiency of workers and start full-scale production by the end of March 2015, which will produce 8,400 vegetables per day."
The plant was transformed from a four-story building in a former floppy disk factory and features germination, seedling, cultivation and harvesting in a clean room at ISO 8 (100,000 federal standards). Pesticides, low-live bacteria and vegetables. Therefore, the plant factory pays great attention to sterilization and sterilization. Before entering the cultivation room, put on a clean room overalls, wash your hands, and then take an air bath. Just like a semiconductor factory.
A pure water preparation device and an electrolysis function water generation device for sterilization and sterilization are installed in the equipment room adjacent to the cultivation room. The pure water (RO water) used in the nutrient solution is obtained by first removing chlorine and bleaching powder from the tap water and then filtering through a reverse osmosis membrane (RO membrane), and then sterilizing the pure water, then adding nutrients, and then supplying the cultivation shed. . The electrolytic function water generating device can simultaneously generate acidic hypochlorous acid water and alkaline water for washing. These two waters are used for hand washing and cleaning items. The hands of the workers and the items brought into the cultivation room must first be cleaned with hypochlorous acid water and then degreased with alkaline water.
The air used in the air conditioner is filtered through 3 filters to maintain cleanliness. Larger dust is filtered through the first filter, particles such as salt having a particle diameter of less than about 1 μm are filtered through the second filter, and particles having a particle diameter of less than 0.37 μm are filtered through a third HEPA filter. A carbon dioxide (CO2) generating device is also provided in the machine room, and the air supplied to the cultivation room increases the CO2 concentration in order to promote photosynthesis. The CO2 concentration is controlled at 800 ppm, which is approximately twice the CO2 concentration in the air.
In addition, the walls of corridors and restrooms are coated with a photocatalyst "RENECAT" developed by Toshiba Materials Co., Ltd. with sterilization and virus inactivation effects. This is a photocatalyst using tungsten oxide, and can also function in low-light visible light such as a fluorescent lamp.
<br> <br> cultivation
management work shed hung
on a tablet CO2 meter and hygrometer for monitoring temperature, humidity, CO2 concentration, by controlling these values automatically kept at the setting value. The pH and conductivity of the nutrient solution are also monitored and controlled by the nutrient supply system.
The plant factory makes full use of Toshiba Group's technology and uses Toshiba's own ICT and lighting products. Daily work instructions and performance are managed through a dedicated ICT system. The tablet on the worker's hand will show at which position the seed is planted, which seedling is moved to which location, etc., and the completed content is entered after the work is completed. This will not only prevent workers from missing a job, but also master the progress of the work. It is also possible to confirm the environmental data of the cultivation room such as temperature, humidity, and pH of the nutrient solution on the tablet.
The lighting used was modified by Toshiba Lighting Technology's plant growth fluorescent lamp "Plantlux". The ratio of fluorescent materials is adjusted for plant factories. But Toshiba said, "The plant factory has adopted fluorescent lamps to control initial investment. In 2015, it will gradually be replaced with LED lamps with low operating costs." In fact, some cultivation sheds have begun to use the LED lights that are easy to control the wavelength for trial cultivation. The goal is to illuminate different wavelengths of light at different stages of growth of the plant to promote photosynthesis and plant growth.
The plant factory adopts a method of changing cultivation sheds from one planting to cultivation according to the growth stage. In the sowing stage, the seeds are planted on a sponge and placed in a small box, placed in the hole of the tray, and a seeding tray has 192 holes. During the cultivation phase, as the plants grow, the capsules are changed to trays with larger spacing. This method is more cumbersome than the method of replacing the cultivation shed with the trays used in other plant factories, but the manner of changing the cultivation density according to the size of the plants and changing to a cultivation shed of different heights can make more efficient use of the space. However, Toshiba also said that it will consider other methods while using it.
The factory now cultivates green leafy vegetables such as loose leaf lettuce, glass lettuce, erect lettuce, Swiss chard, snow, spinach and arugula. In the future, spices, such as basil, dill, and coriander will be cultivated. The canteen, which will be supplied to Toshiba from the end of November, will be sold in the form of boxed vegetables and mixed vegetables in the Kanto region of Japan. In addition, vegetables produced by plant factories are generally more expensive than those cultivated in open-air, but Toshiba does not explicitly announce the price, indicating that “the retail price is inconvenient to announce”.
