[Medical Waste Reduction Project] Site Inspection Vol.3～ ZERO Earth Co., Ltd.～
Hello! This time, I visited ZERO Earth Co., Ltd. which is engaged in recycling infectious medical waste in Ishikawa Prefecture, to hear directly from its president, Iku Nakamura, about the current situation, issues, and future prospects of waste treatment. I will summarize what I actually saw, heard, and thought during my visit, so please read it to the end!
Characteristics of the Sites Visited
Currently, most treatments for infectious medical waste are limited to incineration or melting. Under such circumstances, ZERO Earth Co., Ltd. does not incinerate or melt infectious medical waste but utilizes its unique "Continuous heat sterilization system" to conduct "earth-friendly medical waste treatment" that does not generate CO2 or greenhouse gases and recycles the waste into recyclable resources.
Key points of the interview
1. History of ZERO Earth Co., Ltd.
First, President Nakamura told us about the history of ZERO Earth Co., Ltd.
‟I (President Nakamura) established this company 15 years ago. Until then, I was a salesman for a company that manufactured and installed plants. That company went bankrupt, but I thought I could do better by making use of the know-how I cultivated there, so I went independent. As the main manufacturing machinery, we make recycling plants for concrete, asphalt, empty cans, and PET bottles. The rest is a company that designs and builds gravel, crushed stone, and raw concrete. Then why is it a medical waste?
When we design a plant and manufacture and install it, we need to ask the government. At that time, I was suggested that if you had such expertise in recycling garbage, why don't you think about recycling medical waste?”
President Nakamura used his know-how to start a machine shop when the company was first established. However, to prove the reliability of his products, he started an industrial waste disposal business, which is now active as a company that recycles infectious medical waste.
2. Recycling infectious medical waste
At present, most infectious medical waste is incinerated or melted, and ZERO Earth Co., Ltd.talked about how it has been processed to transform it into a recyclable resource, including its processes and issues.
"The easiest way to dispose of infectious medical waste is to collect it in a dedicated airtight container and incinerate it. I don't think incineration is recycling, but these days recovering heat is considered recycling, called thermal recycling. However, when I started my company 15 years ago, incineration was not regarded as recycling. At that time, all medical waste was disposed of by incineration, so we were told by the government that it would be viable as a business if it could be recycled and that it would be very applicable to the era of environmental conservation in the future. The machines we use now were made based on this."
"This (Infectious Waste Disposal Manual) is a document I used to refer to when I started my company, and it describes how to deal with medical waste. There are various treatment methods for medical waste such as high-pressure steam sterilization, dry heat sterilization, chemical sterilization, and incineration. These are the guidelines. Based on this, we decided to use sterilization instead of incineration for recycling. So I thought, why don't we just leave the materials as they are, kill only the bacteria, and recycle them? This book says that if you heat it for 30 minutes at over 180°C, all the bad bacteria in the world will die.
There have been sterilizers in the past, but it was a batch-type method in which waste was put in a white container in a large pot, sealed completely, and sterilized by applying heat and pressure. I figured we need to put it in and out at least once every few minutes and thought I would rather make a new machine instead.So, we decided to create a machine that automatically comes out sterilized. 30 minutes above 180°C is the same. That's the guideline of the Ministry of Health, Labour and Welfare, so if you don't clear it, you won't get permission even if you make a machine.For the actual mechanism of the machine, we will go over there and explain it to you while looking at the machine. "
< Flow of infectious medical waste treatment at ZERO Earth Co., Ltd. >
(1) Arrange containers exclusively for transporting infectious waste containing infected material on an alignment conveyor.
(2) The container was moved from the alignment conveyor to the charging conveyor by the high letter.
(3) The outer door opens, and the container is conveyed to the charging chamber by the charging conveyor.
(4) The outer door is closed, the inner door is operated, and the waste is put into the crushing chamber.
(5) The crusher starts crushing the waste.
(6) The crushed waste, which passes through a rostle with a 50 mm diameter hole, falls into the sterilization layer and is heated at 180°C for 30 minutes or more to sterilize.
(7) Sterilized wastes are transported by a discharging conveyor and separated into metals and plastics by a magnet.
(8) Metals are recycled and used as raw materials for steel products. Plastics are used as raw materials for PRF.
* PRF is a solid fuel made mainly from waste paper and waste plastics, which are industrial wastes.
★From the materials prepared by President Nakamura
"The reason this machine has magnets is because medical waste is full of scalpels, syringes, and scissors. They come through the crusher, so it's hard to recycle if you don't separate them. The metal of medical instruments is low-level stainless steel. What this means is that most medical devices are now disposable, so while you have to keep costs down, it's not good to get rusty or dull quickly. So we're mixing it up a little bit. That's why medical stainless steel returns to iron as closely as possible when heated. In our company, the temperature is nearly 200 degrees Celsius, so the iron component becomes very strong, and it is made to stick to a magnet.
Metal can be melted and recycled once the bacteria are gone. Other products have had many twists and turns. At the beginning, dyeing factories offered to use the leftover stuff as boiler fuel.
Most medical waste is plastic. We also have gauze, but we don't use gauze much these days, so we end up with plastic. Because it burns well, it has high calories, we started by promising to use it as boiler fuel for dyeing factories. But when I brought it to the dyeing factory as promised, they said they couldn't use it because of the smell. When we put it in the factory, we sterilize it (heat it to 200°C), so the smell is almost gone, once. But they take it to the dyeing factory and pile it in the field before they put it in the boiler. Then, the waste absorbs the moisture in the air and the smell comes out again. Then, in the end, after about a year, they turned me down. This is not recyclable, so it is now used as a raw material for PRF.
At that time, there was a shortage of plastic, so many people said they wanted to use it as a raw material for RPF, and we supplied it to the factory that made PRF. Ultimately, it turns into fuel, but not putting medical waste directly into incinerators and processing it like this reduces greenhouse gas emissions by more than 30%. So we felt that we were contributing a little bit to the environment. However, few years passed and China stopped accepting plastic wastes from Japan. It was about 5 years ago, a little before the coronavirus. Then, plastic garbage in Japan is left over. As a result, every industrial waste company had to deal with all the plastic waste, and the government was in trouble. Then they asked them to use clean plastic as a raw material for RPF. Then medical waste plastic became a nuisance.
So, the first thing I thought about in order to recycle it myself was to return it to oil. When I made a prototype to change it back to oil, it did change back to oil. However, more than half of medical waste plastic is PVC (polyvinyl chloride）. At first, I wanted to use it as fuel for my company's car. But if there is a lot of PVC in it, there is a lot of chlorine, so if you use it to run the engine, the engine will be ruined. So when you think about how to get rid of chlorine, the easiest way is to pass that oil through water and dissolve the salt in the water to desalinate. It went well there, but now the water becomes industrial waste. It will increase waste... I thought it would be bad to do this, so I gave up the oil and decided what to do .... I'm sorry, it's like that now. "
3. Current Situation in Medical Field
This time, I was shown a container for transporting infectious waste in a color I had never seen before. I was very surprised because I thought that only a white container called "MIPPAIL" existed.
"This is a Recycled Pail. The standard white containers are made of virgin material or chips made from petroleum. On the other hand, this container is made by recycling medical waste (which is separated from the hospital), and the CO2 emission is 1/3 of the virgin container. But it doesn't sell. Why? Because It's black. Nurses don't wear black dresses. We think black is fine, but the hospital says that black is not suitable. The ones in treatment rooms and nurse centers have always been white. White is clean and nice. So, you know, the place that they use some of this is a company that does food inspections. As for the test material that comes out from there, I said it doesn't have to be white, and I use this.
When it is recycled, it will be colored because it is mixed with various things, so it is colored black. Some products are colored pink. This is popular with obstetrics and gynecology and other places where there are many women, but on the contrary, the cost is high as the coloring is done. Then, they say that I don't need it if it's expensive."
Bonus clips ~Case Study in Taiwan~
"We also have an office in Taiwan. What they do with medical waste in Taiwan is they put it in this yellow bag and bring it to a room like we freeze tuna in Japan at minus 20 degrees Celsius. There, they put on gloves and masks, and grandpa and grandma sort it out. Because it is before treatment, it has bacteria. But they have their ideas like if it's cold, we can't get infected. So, they sort them out before sterilizing them, and some of them are doing something like chemical recycling.
After sterilization, they are usually put into a crusher to make chips and then recycled. Now it's coming to Japan. There is a triangular red color cone at the construction site. Those are all recycled medical waste products made in Taiwan. The recycling rate in Taiwan is amazing. That's why medical waste is sorted by hand before being recycled. Metal recycling, plastic recycling, and other recycling are also progressing tremendously. I set up an office there to do sales in Southeast Asia, but I still learn a lot from them."
Summary
This time, I visited Zero Earth Co., Ltd. to learn more about the recycling of infectious medical waste. President Nakamura, who greeted me warmly and gave me explanations, was full of inspiring stories about his entrepreneurial spirit, and I had a very rich visit. Through our research and inspection, we have an impression that infectious waste is difficult to dispose of among the waste generated in medical facilities, and we have learned that ZERO Earth has tried and tried to recycle it while being swept by the times. However, I felt that there were still many things that could be done by sorting and sterilizing and that there was a possibility for recycling infectious waste. Also, I was shown black and pink containers for the transportation of infectious waste for the first time, and I felt that it is very important to promote environmentally friendly products in medical practice. President Nakamura said, "Japan is an island country with no resources, so we have to value what is limited." It was very impressive. I thought it would be great if more people in the medical field would pay more attention to the whereabouts of waste, instead of leaving everything to industrial waste companies after leaving the hospital. I strongly felt that this is an issue that we should all work on together. I will make good use of this inspection in my future activities!
Thank you very much for reading the article through to the end!
Nomachi Accelerator Program
Youth Innovator,
Ayasa Terada
Inspection Cooperation：ZERO Earth Co., Ltd.
この記事が参加している募集
この記事が気に入ったらサポートをしてみませんか？