Hospitals battling the fierce Covid-19 surge across the country have exhausted their supply of liquid oxygen cylinders, which is essential to help patients cope with the depletion of oxygen caused by the virus. The Delhi High Court has ordered the Indian government to obtain oxygen in any way possible, although most procurement channels, including imports from other countries, are too slow for the current emergency.
Organizations such as the non-profit Hemkunt Foundation use its humanitarian work for Covid-19 relief. Although it is difficult to find supplies, it is trying to procure oxygen for hospitals, and Tata, one of India’s largest companies, has ordered cryogenics. Containers for transportation help improve the distribution of gas.
But what is a cryogenic container? How can there be a shortage of oxygen, this gas is everywhere, full of the air we breathe? What makes it so difficult to obtain supply in India?
Medical oxygen does come from the air we breathe. In the air separation unit (ASU), air is separated into the main components-nitrogen (78%) and oxygen (21%).
ASU is a plant that processes large amounts of natural gas, ranging from a few hundred tons to 20,000 tons per day. Most of the gas sequestered by ASU is used for industrial purposes—especially in the steel industry—and represents a global market of approximately $5 billion. Asia is the largest market, with more than 40% of the world’s ASU.
ASU uses a process called fractionation, which separates air after it has cooled to a liquid state, and then extracts liquid oxygen from it. Then, if the final destination is close to the production plant, the oxygen will be transported directly through the pipeline connected to the production plant, or through special containers such as aluminum bottles. For larger quantities, use cryogenic vessels, such as those at the inlet of the tower.
Hospitals usually either buy bulk tanks that supply internal oxygen pipes or refillable oxygen cylinders. Oxygen cylinders come in different sizes and can be very heavy. The largest size is about 1.5 meters (60 inches) high, weighs about 60 kg (150 pounds), and contains more than 7,800 liters of liquid oxygen. Covid-19 patients in the hospital need up to 30 liters of oxygen per minute, so it will last about four hours.
Hospitals can also choose to produce oxygen on site, which is usually done through pressure swing adsorption (PSA), which separates the gases present in the air through concentration. The oxygen it produces is less pure than ASU, but it is pure enough for hospital use.
Producing oxygen near or in hospitals also has the advantage of providing more supply than the gas cylinders used in hospitals can guarantee, and ensuring that hospitals will not compete with each other to ensure their oxygen supply.
In the early days of the pandemic, the Indian government tendered 162 PSA factories (including facilities that can condense oxygen from the air) for government hospitals, but it took 8 months to award the contracts. So far, among them, Only 33 installed in 15 states (not all features are available), making most facilities dependent on external supply.
Without sufficient on-site production, India faces two problems: there is not enough oxygen, and it is not distributed efficiently.
According to official government sources, the country produces more than 7,000 metric tons of oxygen per day, and according to the latest estimates provided by government officials to the Delhi High Court, the country needs 8,000 metric tons of oxygen per day. Before the Covid-19 outbreak, the daily demand was about 700 metric tons.
However, as Scroll reported, demand may be underestimated. Although most of the country’s oxygen production is now used for medical purposes, there are still certain industries, such as water purification and pharmaceutical companies, that allow some of the oxygen to be used in emergency situations. In total, they consume approximately 2,500 metric tons per day-making the overall available supply approximately 4,500 metric tons.
In addition, the number of cases has increased dramatically in the past few days, so the daily shortage may be at least 3,500 metric tons, and it is still increasing. Even if the government plans to import another 50,000 tons, the oxygen supply will inevitably be insufficient.
In addition, any available oxygen cannot reach where it is needed. Special oil tankers are needed to transport large amounts of oxygen between states, but not enough to transport the entire oxygen production. Similarly, there is a shortage of gas cylinders and cannot be refilled fast enough to meet demand.
The government has recently taken measures to help in this regard, allowing tankers to drive on any road without restrictions such as state specific permits, giving them priority status similar to ambulances. Cylinder filling facilities are now also allowed to operate 24 hours a day, 7 days a week, and cylinders normally used for other gases become oxygen containers after disinfection.
Post time: Sep-14-2021