WHEN swab tests and Covid-19 vaccination sites opened in Davao City, medical wastes also increased dramatically.
From personal protective equipment (PPE), syringes, gloves, to masks and cotton balls – everything needs to be properly disposed of to prevent further contamination. These types of wastes are considered toxic.
Hospitals and other establishments are strictly mandated by the Department of Environment and Natural Resources – Environment Management Bureau (DENR-EMB) to have a waste disposal system able to properly treat these wastes. Aside from that, these types of wastes should not be mixed with the other non-toxic wastes upon collection and in the landfill.
The Association of Regional Executives of National Agencies (Arena) in Davao Region leads the Resbakuna for government employees in different parts of Davao City. Their vaccination sites are located at the University of the Philippines Mindanao, University of Southeastern Philippines Obrero Campus, and Police Regional Office-Davao Region in Camp Catitipan.
In the first phase of their vaccination from June 30 to July 2, 2021, a total of 2,000 government employees were already vaccinated, while they targeted to vaccinate 15,000 government employees in total. With this number of individuals vaccinated, one can only imagine the amount of medical waste produced on a daily basis.
Department of Science and Technology (DOST) Davao Regional Director Dr. Anthony Sales said they partnered with Radicor Solutions, founded by Engr. Roderick Dayot, a local inventor based in Davao City for the disposal effort of the medical waste from Arena XI Resbakuna campaign.
“Nitro-sterilization is a new technology developed by Engr. Roderick Dayot, one of our inventors here in Davao. We requested his assistance in our disposal efforts of the medical waste for Arena XI... We have a law against incineration, so the invention of Engr. Dayot does not use fire. He uses high-pressure, high-temperature nitrogen to sterilize these medical wastes,” said Dr. Sales, who also leads Arena XI.
What is nitro-sterile technology?
Nitro-sterile, using a US-patented machine, is a technology that uses an oxygen-free chamber to sterilize medical waste. This chamber is filled with pressurized high-temperature nitrogen to disinfect and shred medical, clinical, and pathological waste until they become fine, unrecognizable materials before they are disposed of to a special waste cell. Dayot said they reduce the volume of medical waste by 60 percent.
“The technology that we have now is cheaper. We are utilizing a system from a readily available material – nitrogen. It is also non-pollutant as it does not emit toxic chemicals in the waters and in the air. We extract nitrogen, put it under high-pressure, high-temperature 250 degrees Celcius, it gets contact with the medical waste and sterilizes it. After the procedure, what comes out of the air is still nitrogen,” explained Dayot.
He added the high-temperature standard of DOST considered safe for sterilization is at 121 degrees Celsius but at Radicor, they do nitro-sterile at 250 degrees Celsius, more than the minimum standard.
He said the machine that they use has the capacity to process five tons of medical waste a day. The special waste cell (special landfill), where the shredded medical waste ends up after sterilization, has a total capacity of 10,000 tons and Dayot said they estimate it can withstand up to five years of operation.
Dayot said what Radicor advocates for is improved treatment procedures of medical waste as it continues to be a problem with the continuous surge in Covid-19 cases.
“We don’t want incineration anymore,” he added.
As a point of comparison, he said there is an existing technology that treats medical waste using steam. However, the problem with this technology is it requires too much water. For every kilo of medical waste, two liters of water are needed. Another technology called microwaving utilizes high levels of radiation putting the operators and those working close to the machinery at risk of overexposure to radiation. He said other existing technology treating medical waste is effective but has risks of polluting water and air because of the residual wastes.
From the vaccination sites designated by the Arena XI Resbakuna, medical wastes are stored and sealed in storage containers. Personnel from Radicor make sure that the medical wastes are properly handled as they are brought to the waste treating facility in New Carmen, Tugbok District. They have another facility in the same area that is set to finish construction and completion of the Environmental Compliance Certificate (ECC) within the year. The facility is 1.8 hectares wide catering to a closed-loop system – from transfer of medical waste from source to sterilization to disposal in special landfills.
“For the collected waste in UP and USeP, as to date, it’s about 25 containers already. Each container weighs eight kilos. So that’s about 200 kilos of vaccine waste collected [from the Arena XI vaccination alone],” Dayot said.
Treatment of other waste
According to Sales, nitro-sterile technology is only good for solid medical waste. A different technology is used for the liquid medical waste generated by hospitals and clinics.
“With regards to liquid waste, we have a technology. Vertical Helophyte Filtration System. We’ve installed it already in one hospital in Tagum City. It’s effective in treating wastewater generated by the hospital. Nakita namo na paggawas gyud sa effluent na niagi sa filter, clear kaayo siya. Limpyo kaayo siya when we analysed in the laboratory. Results have shown na compliant sya sa DENR standards. This technology can be used for the treatment of wastewater from hospitals and clinics,” said Sales.
SunStar Davao published an article in 2018 saying that the Dutch water engineering and waste management expert Sean Ligvoet first introduced the technology to DOST. VHFS is a filtering technology that uses plants as one of the materials that absorb pollutants from wastewater. This technology was adapted from the Netherlands where it is used by households. Pre-pandemic, it was first eyed by DOST to be used in food processing establishments and small businesses.
“This equipment will be attached to the septic tank and then the water from the septic tank will be sucked out to proceed to the filter. When it goes out, it is already clean. The filtered water will be compliant with class A or class B water of the DENR. It means that this can be immediately disposed of to our wastewater,” said Sales in a previous interview.