# Oxygen: Overview

Steelmaking, coal gasification and hospital wards

Source page: https://www.materialinsights.org/chemicals/oxygen/overview/

What this tab covers What the chemical is, how big its market is, what it is used for (with shares, volumes, why it wins and what could replace it), and its chain from raw material to end user. Ends with three things to remember.

Oxygen is 21% of air by volume. It is made by cooling air until it liquefies and distilling it in an air separation unit (ASU), or by adsorbing nitrogen out of air in smaller PSA units. About 400 Mt a year is produced (Thunder Said Energy, 2023), more than any chemical except sulphuric acid, most of it on or next to steel plants. Electricity is the main cost, so its carbon footprint follows the grid. India learnt its strategic value in 2021, when medical demand jumped to nearly 9,000 t a day.
 Volume about 400 Mt a year (2023) Market value not published for oxygen alone; the whole industrial gases market is about $94-100 billion a year (2024) Growth industrial gases about 5% a year to 2030 (MarketsandMarkets); oxygen volume tracks steel and coal gasification Thunder Said Energy (May 2023); MarketsandMarkets (2024)

#### Key uses

| Use | Share | Annual volume | Why this commodity | Alternatives |
|---|---|---|---|---|
| **Steelmaking (basic oxygen furnaces, blast furnace enrichment, electric arc furnaces)** | n/a | largest single use; not published as a sharebasis | Blowing pure oxygen through molten pig iron burns out carbon in about 20 minutes, against hours with air. Enriching blast furnace air with oxygen raises output and cuts coke use. Integrated mills build their own ASUs or contract a gas company to build one on site. USGS MCS 2026 (steel output); indicative usage | Air (open hearth, now obsolete) Scrap-based EAF uses less oxygen per tonne |
| **Chemicals and coal gasification (syngas, ethylene oxide, TiO2, propylene oxide)** | n/a | not publishedbasis | Gasifiers and partial oxidation units need pure oxygen so that the syngas is not diluted with nitrogen. Ethylene oxide plants use oxygen rather than air for higher selectivity. IEA GHR 2025 (coal use) | Air-blown processes with lower efficiency |
| **Healthcare (medical oxygen)** | n/a | India peak about 9,000 t a day (May 2021) against a first-wave peak of 3,095 t a daybasis | Oxygen therapy for respiratory illness, surgery and intensive care. Hospitals take liquid oxygen in cryogenic tanks or cylinders, or run on-site PSA plants. Deccan Herald citing Government of India (23 Jul 2021) | On-site PSA (93% oxygen) Oxygen concentrators |
| **Non-ferrous metals, glass and pulp** | n/a | not publishedbasis | Oxy-fuel burners in glass furnaces and copper smelters raise flame temperature and cut fuel use and NOx. Pulp mills use oxygen for delignification and bleaching. industry practice (indicative) | Air-fuel firing |
| **Welding, cutting, water treatment, aquaculture** | n/a | not publishedbasis | Oxy-acetylene cutting and wastewater aeration need small, distributed volumes sold at much higher prices per tonne than pipeline oxygen. industry practice (indicative) | Plasma cutting Air aeration |

 No public global split by use was found. Steel is the largest use by volume. India's commercial (non-captive) gas market gives a guide by revenue: metallurgy 39% of sales and oxygen (industrial and medical) 31% of the market in 2024 (gasworld).

#### From raw material to user

1. **Air intake and compression** Air is filtered and compressed to about 5-6 bar; compression is most of the ASU's power use.
2. **Purification** Molecular sieves remove water and CO2 so they do not freeze in the cold box.
3. **Cryogenic distillation** Air is cooled to about -185 C and separated in columns into oxygen, nitrogen and argon. The thermodynamic minimum is 51 kWh per t of oxygen (Thunder Said Energy).
4. **Delivery by pipeline (tonnage)** Large plants pipe gaseous oxygen over the fence to steel mills or gasifiers under 15-20 year contracts.
5. **Liquefaction and bulk delivery** Some output is liquefied and trucked as liquid oxygen at -183 C; India had 1,244 LMO tankers in July 2021.
6. **Cylinders and hospital supply** Liquid is vaporised into cylinders or hospital tanks; India sanctioned 1,222 PSA plants with 1,772 t a day of capacity in 2021.

#### Three things to know

- About 400 Mt of oxygen is made each year, mostly for steel (Thunder Said Energy, 2023).
- Power is the main cost: an ASU uses roughly 200-300 kWh per t of gaseous oxygen, against a theoretical minimum of 51 kWh (indicative; TSE).
- India's liquid medical oxygen output rose from 5,700 t a day (Aug 2020) to 9,690 t a day (May 2021) by diverting steel-plant oxygen.

#### Read the tabs
[Production route](https://www.materialinsights.org/chemicals/oxygen/routes/)[Production](https://www.materialinsights.org/chemicals/oxygen/production/)[Feedstocks](https://www.materialinsights.org/chemicals/oxygen/feedstocks/)[Cycles](https://www.materialinsights.org/chemicals/oxygen/cycles/)[Trading](https://www.materialinsights.org/chemicals/oxygen/trading/)[Movement](https://www.materialinsights.org/chemicals/oxygen/movement/)[Regulation](https://www.materialinsights.org/chemicals/oxygen/regulation/)[Characteristics](https://www.materialinsights.org/chemicals/oxygen/characteristics/)[Emissions](https://www.materialinsights.org/chemicals/oxygen/emissions/)

## Other sections

- [Summary](https://www.materialinsights.org/chemicals/oxygen/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/oxygen/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/oxygen/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/oxygen/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/oxygen/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/oxygen/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/oxygen/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/oxygen/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/oxygen/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/oxygen/characteristics/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/oxygen/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/oxygen/links/index.md)