Global Sulfur Dioxide (SO₂) Control Market Outlook, 2031

Sulphur dioxide control is a broad, multi-technology field that touches almost every heavy industry, spanning flue gas desulphurisation, sulphur recovery units, sulphuric acid plants, sorbents and reagents, desulphurisation catalysts, marine exhaust gas cleaning and continuous emissions monitoring. Global SO₂ emissions have fallen sharply in Europe and North America since the acid rain programmes of the 1990s, including the US Clean Air Act Amendments of 1990, and in China since the 2010s, yet they remain high in India, Southeast Asia, the Middle East and Africa and from smelting and shipping. Coal plants remain the largest emitters, and in India coal-based power still supplied about 75% of electricity in 2024-25 from only around 47% of installed capacity. Technologies are mature and efficient: wet FGD removes 95% to 99% of SO₂, modern Claus units with tail gas treatment recover more than 99.9% of sulphur, and refinery hydrotreating cuts diesel and gasoline sulphur to 10 to 15 parts per million. Power generation is still the largest end use at around 40% of demand, but refining and gas processing already account for roughly a quarter, metals and mining about 15% and shipping about 10%, a mix tilting steadily away from coal. Suppliers range from Mitsubishi Heavy Industries, Babcock & Wilcox and Andritz in FGD to Topsoe, Shell Catalysts & Technologies, Honeywell UOP and Axens in catalysts, and Carmeuse, Lhoist and Graymont in sorbents.

Policy has become the decisive swing factor since 2024. India's July 2025 notification exempted about three quarters of its coal fleet from FGD, removing a large expected pipeline of orders, and the US EPA's June 2025 proposal to repeal the 2024 MATS amendments eased pressure on American utilities. Against that, China continues to apply ultra-low emission rules to steel, coking and cement, the IMO's 0.50% sulphur cap from 2020 and new emission control areas in the Mediterranean from 2025 and the Canadian Arctic and Norwegian Sea from 2027 sustain demand for low-sulphur fuels and marine scrubbers, and sour gas and refining projects in the Gulf keep sulphur recovery capacity growing. The 2026 Iran war and the closure of the Strait of Hormuz, through which an estimated 45% to 50% of seaborne sulphur trade normally passes, disrupted Gulf refineries, gas plants and sulphur exports from March, pushing sulphuric acid above USD 500 per tonne in some markets by May. Honeywell's completion of its £1.325 billion acquisition of Johnson Matthey's Catalyst Technologies in July 2026 further concentrated catalyst supply. Through 2031, the Middle East and Southeast Asia are expected to be the most dynamic regions, and power generation's share of demand is expected to keep slipping as industrial and process controls grow.

Drivers Emission Standards for Power, Industry and Shipping Governments regulate SO₂ to reduce acid rain, respiratory disease and fine particulate pollution, and limits apply to power plants, steel mills, smelters, cement kilns, refineries and ships. China's industrial ultra-low emission programmes, EU industrial emissions rules, US Clean Air Act programmes and IMO sulphur limits drive investment in FGD, sulphur recovery, low-sulphur fuels and scrubbers. Countries in Southeast Asia, the Middle East and Latin America are tightening standards.
Refining, Sour Gas and Metal Processing Growth Production of ultra-low-sulphur fuels requires hydrodesulphurisation and sulphur recovery in refineries, and development of sour gas fields in the Middle East, Central Asia and elsewhere requires large sulphur recovery units. Growth in copper, nickel and zinc smelting for the energy transition increases SO₂ capture in acid plants. These sectors provide steady demand regardless of coal power trends.

Challenges Coal Phase-Outs and Regulatory Reversals The decline of coal power in Europe, North America and eventually China reduces long-term demand for power plant FGD, and regulatory reversals, such as India's July 2025 FGD exemptions and US proposals to roll back power sector rules, reduce near-term demand. Uncertainty about enforcement in developing countries complicates investment planning for suppliers.
Cost, Water and By-Product Management SO₂ control systems require significant capital and operating costs, including reagents, energy and water, and generate by-products such as gypsum, wastewater and spent sorbents that require markets or disposal. Sulphur recovered in refineries and gas plants must be sold, and sulphur prices are volatile. Smaller facilities may find compliance costs high.

Trends Shift from Power to Industrial and Marine SO₂ Control As coal power declines in many regions, SO₂ control demand is shifting toward steel, non-ferrous smelting, cement, waste-to-energy, refining, gas processing and shipping, which require tailored solutions such as acid plants, regenerable scrubbers and marine systems. Multi-pollutant control systems combining SO₂, NOx, particulate and mercury removal are increasingly common.
Resource Recovery and Circular By-Products SO₂ control is increasingly linked to resource recovery, with gypsum used in construction, ammonium sulphate used as fertiliser, recovered sulphur used in sulphuric acid and fertilisers, and wet sulphuric acid processes producing commercial acid. Regenerable processes reduce waste and reagent use, supporting circular economy goals.



Flue gas desulphurisation accounts for about 45% of SO₂ control demand because power plants, steel mills, smelters and incinerators must remove SO₂ after combustion, requiring large absorbers, reagent systems and by-product handling at very large scale. Flue gas desulphurisation, first commercialised at scale in Japan and the United States in the 1970s, spans wet limestone, seawater, ammonia, magnesium and caustic systems, semi-dry spray dry absorbers, circulating dry scrubbers and dry sorbent injection. Large wet FGD projects at coal plants take two to four years to build and treat millions of cubic metres of flue gas per hour, so a handful of projects in China, India or Southeast Asia shape annual activity. Sulphur recovery units and sulphuric acid plants account for about 20% of demand. Claus units convert hydrogen sulphide from refineries and gas plants into elemental sulphur, tail gas treatment units capture residual sulphur to reach recovery efficiencies above 99.9%, and smelter acid plants convert concentrated SO₂ from copper, zinc and nickel smelting into sulphuric acid sold to fertiliser and mining customers. Wet sulphuric acid processes, such as Topsoe's WSA, handle more dilute gases. Reagents and sorbents, including limestone, lime, trona, sodium bicarbonate, ammonia and magnesium hydroxide, account for around 15% of demand and provide recurring revenue tied to plant operating hours. Desulphurisation catalysts, including hydrotreating catalysts for fuels, Claus and tail gas catalysts and vanadium-based SO₂ oxidation catalysts for acid plants, accounted for about 12%. Marine exhaust gas cleaning systems form a distinct segment linked to fuel price spreads and emission control areas. Continuous emission monitoring systems, engineering, operation and maintenance services and performance optimisation complete the solution set, and their share is rising as installed bases age and operators seek lifecycle support rather than new builds. Engineering, procurement and construction contractors often integrate several of these elements into single packages for refinery and smelter projects.

Post-combustion controls hold the largest share of SO₂ control demand because most coal, oil and process emissions must be treated after combustion, while pre-combustion and process controls dominate refining, gas processing and metal smelting. Post-combustion controls, including FGD and marine scrubbers, account for an estimated 55% of SO₂ control demand, as they are the only practical option for existing coal plants, industrial boilers and many smelters burning or processing sulphur-bearing materials. Pre-combustion controls prevent SO₂ from forming by removing sulphur before fuel is burned, and they are central to transport fuel standards. Hydrodesulphurisation in refineries brings diesel and gasoline to 10 to 15 parts per million sulphur and marine fuels to 0.50% or 0.10%, while coal washing and fuel switching from coal or heavy oil to natural gas or low-sulphur fuels achieve similar results in power and industry. This category accounts for roughly 25% of demand. Combustion controls, such as limestone injection in circulating fluidised bed boilers, capture sulphur in the furnace and are common in industrial and smaller power plants burning coal, petcoke and biomass. Process controls, including sulphur recovery in gas processing and acid plants at smelters, capture sulphur as a saleable product, and they account for about 20% of demand. The selection among these approaches depends on fuel sulphur content, plant size, regulatory limits, by-product markets and capital availability. Operators increasingly combine approaches, for example switching to lower-sulphur coal and adding dry sorbent injection rather than building full wet FGD, or pairing refinery hydrotreating with FCC SOx additives. Integrated multi-pollutant systems that address SO₂, NOx, particulates and mercury together are gaining ground at new industrial plants in Asia. In marine applications, the same choice plays out between burning compliant low-sulphur fuels, which shifts desulphurisation upstream to refineries, and installing onboard scrubbers that allow continued use of cheaper high-sulphur fuel oil.

Power generation remains the largest SO₂ control end use at about 40% of demand because coal and lignite plants emit more SO₂ than any other sector, although refining, metals and shipping are steadily gaining share as coal declines. Power generation accounts for about 40% of SO₂ control demand, concentrated in coal and lignite plants in China, India, Indonesia, Vietnam, Turkey, South Africa and Eastern Europe. Its share is declining, as Western coal plants retire and India's July 2025 exemptions reduce new FGD orders, and it is expected to fall below 35% of demand by 2031. Refining and gas processing accounted for about 25%, including hydrodesulphurisation units, sulphur recovery and tail gas treatment, and FCC SOx controls, with major projects at refining and sour gas complexes in Saudi Arabia, the UAE, Qatar, Kuwait, India and China. Metals and mining accounted for around 15%, covering copper, nickel, zinc and lead smelters, steel sintering and pelletising and alumina refining, a segment benefiting from demand for energy transition metals. Marine shipping accounted for about 10%, through exhaust gas cleaning systems and the refinery desulphurisation required to produce compliant fuels. Cement kilns, chemical plants, pulp and paper mills, glass furnaces and waste incinerators accounted for the remaining 10%, each with sector-specific emission limits. Fertiliser and sulphuric acid producers are linked to the market as major buyers of recovered sulphur and acid. Industrial users are increasingly important because their emission limits are tightening in Asia under ultra-low emission programmes and in Europe under the revised Industrial Emissions Directive, whereas power sector rules are being relaxed in some countries. This shift favours suppliers with broad industrial process expertise rather than those focused solely on utility FGD. Pulp and paper mills, in particular, use recovery boilers and scrubbers that capture reduced sulphur compounds along with SO₂.

Equipment and systems account for the largest share of SO₂ control spending because new FGD units, sulphur recovery plants and scrubbers are capital intensive, while consumables, monitoring and services provide growing recurring revenue as installed bases age. Equipment and systems, including absorbers, spray towers, reagent preparation systems, gypsum dewatering, sulphur recovery reactors, acid plant converters, marine scrubber towers and associated fans, pumps and ductwork, account for an estimated 55% of SO₂ control demand. Spending is project-driven and lumpy, depending on new coal, industrial, refinery and gas processing investments and regulatory deadlines. Consumables, including limestone, lime, sodium-based sorbents, ammonia, magnesium hydroxide and catalysts, account for around 27% of demand and grow steadily with operating hours and the number of installed systems. A single large coal unit can consume several hundred thousand tonnes of limestone annually, while refineries replace hydrotreating catalysts every two to five years. Services, including engineering studies, operation and maintenance contracts, performance testing, spare parts, absorber relining and upgrades, accounted for about 13% and are expanding as the installed base of FGD and sulphur recovery units ages. Monitoring equipment and software, including continuous emission monitoring systems for SO₂ and data handling for regulatory reporting, accounted for around 5% and are essential for compliance in all regulated markets. Digital services, such as AI-based reagent optimisation, predictive maintenance and remote performance monitoring, are increasingly bundled with service contracts, helping operators reduce reagent consumption by several percent. The growing weight of consumables and services makes supplier revenues less dependent on new coal projects, an important structural shift given the decline in Western power plant construction and India's reduced FGD pipeline. Large utilities and industrial groups are also signing performance-based contracts in which suppliers guarantee emission levels and reagent efficiency over multi-year periods, sharing savings with the operator.

Asia-Pacific accounts for more than half of global SO₂ control spending, led by China and India, while North America, Europe and the Middle East are significant markets with different drivers. Asia-Pacific accounts for more than half of the global SO₂ control market. China has the world's largest installed base of FGD and continues to invest in industrial SO₂ control for steel, coking, cement and non-ferrous smelting under ultra-low emission programmes, along with refinery desulphurisation. India's market was reshaped by the July 2025 notification exempting Category C coal plants, about three quarters of capacity, from FGD, though Category A plants and some Category B plants must still install controls, and refinery and smelter investments continue. Southeast Asia, Japan, South Korea and Australia add demand from power, refining, smelting and shipbuilding. North America accounts for about 15%, with demand from refineries, gas processing, smelters and waste-to-energy, while power plant FGD declines with coal retirements and proposed rollbacks of the 2024 MATS amendments. Europe accounts for about 15%, with strict industrial emission standards, waste-to-energy, refining and marine scrubber suppliers, while coal phase-outs reduce power sector demand. The Middle East accounts for around 10%, with large sulphur recovery units at gas processing and refining complexes in Saudi Arabia, the UAE, Qatar and Kuwait, which were disrupted by the 2026 Iran war, and it is expected to be one of the fastest-growing regions. Latin America and Africa have demand from mining, smelting and refining.

July 2026 – Honeywell completes acquisition of Johnson Matthey's Catalyst Technologies business: Honeywell completed its £1.325 billion purchase of Johnson Matthey's Catalyst Technologies business, strengthening its refining and gas processing catalyst portfolio, including desulphurization technologies.

March 2026 – Hormuz closure disrupts Gulf refining, gas processing and sulphur exports: The Iran war and closure of the Strait of Hormuz disrupted operations and exports at Gulf refineries and gas plants, which are major producers of recovered sulphur.

July 2025 – India revises SO₂ norms for thermal power plants: India's environment ministry exempted Category C coal plants from FGD installation and introduced a location-based approach, sharply reducing expected FGD demand.

June 2025 – US EPA proposes repealing 2024 MATS amendments: The EPA proposed repealing stricter 2024 emission standards for coal-fired power plants as part of a broader review of power sector rules.

May 2025 – Mediterranean emission control area takes effect: The Mediterranean Sea became a sulphur emission control area, requiring ships to use 0.10% sulphur fuel or scrubbers.

December 2015 – India issues SO₂ emission norms for thermal plants: India's environment ministry introduced SO₂, NOx and particulate standards that originally required all coal plants to install FGD by 2017.


Considered in this report
• Historic Year: 2020
• Base Year: 2025
• Estimated Year: 2026
• Forecast Year: 2031

Aspects covered in this report
• Global Sulfur Dioxide (SO₂) Control Market with its value and forecast along with its segments
• Various drivers and challenges
• Ongoing trends and developments
• Top profiled companies
• Strategic recommendation

By Solution
• Flue Gas Desulphurisation
• Sulphur Recovery Units
• Sulphuric Acid Plants
• Reagents and Sorbents
• Desulphurisation Catalysts
• Marine Exhaust Gas Cleaning
• Monitoring and Services

By Control Approach
• Pre-Combustion Controls
• Combustion Controls
• Post-Combustion Controls
• Process Controls

By End Use
• Power Generation
• Refining and Gas Processing
• Metals and Mining
• Marine
• Cement
• Chemicals
• Waste Incineration

By Offering
• Equipment and Systems
• Consumables
• Services
• Monitoring