Global NOx Scrubber Market Outlook, 2031

NOx scrubbers occupy a specialised but fast-moving corner of emissions control. Instead of reducing nitrogen oxides over a catalyst, they oxidise poorly soluble nitric oxide into higher oxides using hydrogen peroxide, sodium chlorite, chlorine dioxide or ozone, then absorb the products in alkaline or reducing liquids, with well-designed systems removing 90% to 99% of nitrogen dioxide. The approach works where SCR and SNCR fail: in gas streams below about 150°C, saturated with moisture, laden with acids or dust, or where NOx comes from chemistry rather than combustion, such as the dense brown fumes released when stainless steel or titanium is pickled in nitric acid. Ozone-based low-temperature oxidation, commercialised as LoTOx and used at many US refinery fluid catalytic cracking units since the 2000s, converts NOx into nitrogen pentoxide that dissolves readily in existing wet scrubbers. Chemical and process industries, including nitric acid production, metal pickling, explosives and fine chemicals, account for about 40% of demand, semiconductors and electronics around 30% and refinery FCC units about 15%. Multi-stage oxidation-absorption scrubbers make up roughly 55% of installed systems. Suppliers include Tri-Mer, Linde, Belco within Elessent Clean Technologies, Envitech, CECO Environmental, Verantis, Ebara, Kanken Techno, Edwards and Global Standard Technology.

What makes this niche compelling for researchers is its exposure to some of the fastest-growing investment cycles in industry. Semiconductor fab construction has surged since the US CHIPS and Science Act was signed in August 2022 and the EU Chips Act entered into force in September 2023, alongside heavy investment in Taiwan, South Korea, Japan and China to meet demand for AI chips, and a single leading-edge fab can operate hundreds of point-of-use abatement units to treat nitric acid etching and nitrogen-containing process gases. Battery cathode and precursor plants using nitric acid and nitrates, stainless steel and titanium pickling lines and nitric acid plants add further demand, while workplace exposure limits for nitrogen dioxide, tightened in the EU in recent years, and enforcement against visible brown plumes in China and India push retrofits. The EU's revised Industrial Emissions Directive, in force since August 2024, broadens industrial permitting requirements. Constraints include high operating costs, since ozone generation consumes significant electricity and oxidants are consumed continuously, and nitrate-bearing wastewater that must be treated, with energy price rises after the 2026 Iran war adding pressure. Through 2031, NOx scrubbing is expected to outpace NOx control as a whole, with Asia-Pacific holding around half of global installations and North America about a quarter.

Drivers Semiconductor and Electronics Manufacturing Growth Semiconductor fabs use nitric acid and nitrogen-containing process gases and must abate NOx emissions at point of use and in central exhaust systems. Massive investment in new fabs in Taiwan, South Korea, Japan, China, the United States and Europe from 2022 to 2026, driven by AI chip demand and government incentives, increases demand for NOx abatement scrubbers.
Industrial Process Emissions and Workplace Safety Metal pickling and etching with nitric acid, nitric acid and fertiliser production, explosives manufacturing, pharmaceutical synthesis and battery materials processing generate NOx that must be controlled to meet emission limits and protect workers from toxic fumes. Stricter industrial regulations in China, India and Europe and enforcement against visible brown plumes support investment.

Challenges Operating Costs and Wastewater NOx scrubbers consume oxidants such as ozone, hydrogen peroxide or chlorine dioxide and alkaline reagents, and ozone generation consumes significant electricity, making operating costs relatively high. Scrubbers generate wastewater containing nitrates, nitrites and other compounds that must be treated. Energy price increases, such as in 2026, raise costs.
Niche Market and Competition from SCR and SNCR Where gas conditions allow, SCR and SNCR are usually more cost-effective for NOx control, limiting NOx scrubbers to niche applications. The market is fragmented, with many small engineering firms and customised projects, and demand depends on capital spending in semiconductors, chemicals and metals, which can be cyclical.

Trends Ozone-Based Low-Temperature Oxidation Ozone injection oxidises NOx to highly soluble higher oxides that can be captured in existing wet scrubbers, allowing combined NOx, SOx and particulate control in a single system at low temperatures. This approach is used in refinery FCC units, industrial boilers and other applications, and improvements in ozone generator efficiency reduce costs.
Integrated Multi-Pollutant and Semiconductor Abatement NOx scrubbers are increasingly integrated with acid gas, particulate and volatile organic compound control, and semiconductor abatement systems combine thermal, plasma and wet scrubbing to treat NOx, fluorinated gases and other emissions. Digital monitoring and automated reagent dosing improve efficiency and compliance.



Oxidation-absorption multi-stage wet scrubbers account for about 55% of NOx scrubber installations because they reliably capture NOx from acidic, wet and low-temperature process gases in nitric acid, pickling and chemical plants where catalytic methods are impractical. Oxidation-absorption multi-stage wet scrubbers account for about 55% of installed systems. A typical system uses a first stage to oxidise nitric oxide to nitrogen dioxide with hydrogen peroxide, sodium chlorite or chlorine dioxide, followed by one or more absorption stages using sodium hydroxide, sodium sulphide, urea or other reducing or alkaline solutions to capture the higher oxides. Some designs recover nitric acid for reuse, improving economics at pickling and chemical plants. Packed tower and spray tower absorbers are the main hardware, built from fibre-reinforced plastic, stainless steel or high-nickel alloys depending on corrosivity. Ozone-based low-temperature oxidation systems account for around 25% of installations, injecting ozone generated on site into flue gas ahead of an existing or new wet scrubber, converting NOx into nitrogen pentoxide that dissolves readily, and enabling simultaneous removal of SOx and particulates. Linde's LoTOx technology is used in refinery FCC units and industrial boilers, often paired with wet gas scrubbers. Semiconductor abatement scrubbers account for about 20%, including point-of-use wet, burn-wet and plasma-wet units installed beside individual process tools, and central scrubbers treating combined fab exhaust, with suppliers such as Ebara, Kanken Techno, Edwards and Global Standard Technology. Ancillary equipment, including ozone generators, oxidant dosing skids, wastewater treatment for nitrate and nitrite removal and continuous emission monitoring, forms an important part of project scope. Combined SOx and NOx scrubbing for ships and power plants is under development but remains at pilot scale. System design typically targets removal efficiencies of 90% to 99% for NO₂ and somewhat lower for NO, depending on oxidation stage performance. Chemical consumption rises with inlet NOx concentration, making process optimisation important for operating cost.

Chemical and process industries account for about 40% of NOx scrubber demand because nitric acid production, metal pickling, explosives and fine chemical synthesis generate concentrated NOx fumes that are toxic, visible and subject to strict workplace and emission rules. Chemical and process industries account for about 40% of NOx scrubber demand. Nitric acid and nitrate plants use absorption towers and tail gas scrubbers to recover NOx and meet emission limits. Stainless steel, titanium, nickel alloy and aluminium pickling and etching lines using nitric and mixed acids release dense brown NOx plumes, making scrubbers essential for permits and worker safety. Explosives and propellant manufacturing, pharmaceutical and fine chemical synthesis involving nitration, and metal dissolution in refining and recycling are other important applications. Battery cathode and precursor production, which in some routes uses nitric acid or nitrate salts, has become a growth area. Semiconductors and electronics account for around 30% of demand, covering wafer fabs, printed circuit board plants, display panel factories and solar cell manufacturing, where nitric acid etching and nitrogen-containing gases require point-of-use and central abatement. Refinery FCC units account for about 15%, using wet gas scrubbers with ozone injection to address NOx, SOx and particulates together, a configuration adopted at many US refineries under environmental consent decrees. Other applications, including low-temperature combustion sources, glass manufacturing, waste treatment, laboratories and marine pilots, accounted for the remainder. Demand within each industry depends heavily on new plant construction and regulatory enforcement, with Chinese and Indian authorities increasingly targeting visible NOx plumes from metal finishing and chemical plants. Workplace exposure limits for nitrogen dioxide, tightened in Europe in recent years, also drive investment. Pharmaceutical and fine chemical producers in India and China, which perform many nitration reactions for active ingredients, are becoming more important buyers as environmental enforcement tightens.

Central industrial-scale scrubbers account for the largest share of NOx scrubber demand because process plants and refineries treat large combined exhaust volumes, while point-of-use units are essential in semiconductor fabs and packaged systems serve smaller facilities. Central and industrial-scale scrubbers account for an estimated 60% of NOx scrubber demand, treating exhaust from entire pickling lines, nitric acid plants, chemical processes, refinery units and semiconductor fab central exhaust systems. These are typically custom-engineered projects taking six to eighteen months to deliver, involving multiple absorption stages, oxidant systems, fans, ductwork and wastewater treatment. Point-of-use scrubbers account for around 25% of demand and are installed beside individual semiconductor process tools to treat hazardous gases before they enter central exhaust, with a large fab potentially using hundreds of units. Their market is closely tied to fab construction and tool installation cycles. Packaged and modular scrubbers account for about 15% and serve smaller metal finishing shops, laboratories, pilot plants and batch chemical processes, offering standardised designs, shorter lead times and lower engineering costs. Selection depends on gas volume, NOx concentration, the mix of NO and NO₂, presence of other acid gases and particulates, space availability and wastewater handling capacity. Materials of construction range from polypropylene and fibre-reinforced plastic for acidic gases to stainless steel and alloys where temperatures or chlorides are higher. Suppliers increasingly offer containerised and skid-mounted systems that can be installed quickly and relocated. Digital controls adjust oxidant dosing to fluctuating NOx loads, reducing reagent costs. Remote monitoring and service agreements are becoming standard for central systems, providing suppliers with recurring revenue over equipment lifetimes. Integrated packages combining NOx, acid gas and particulate removal are increasingly preferred to separate units, saving space and reducing capital cost. Larger systems often include redundant fans and pumps to ensure continuous operation.

New installations account for a large share of NOx scrubber demand because semiconductor fabs, battery materials plants and chemical facilities under construction require abatement from start-up, while retrofits and upgrades address tighter limits and visible plumes at existing sites. New installations account for an estimated 55% of NOx scrubber demand, driven largely by semiconductor fab construction in Taiwan, South Korea, Japan, China, the United States and Europe, new battery cathode and precursor plants in Asia, North America and Europe, and new chemical and metal processing facilities in China and India. Semiconductor projects are particularly influential, as a single leading-edge fab can involve hundreds of abatement units and large central systems, with NOx scrubbing forming part of broader acid, alkali and fluorinated gas abatement packages. Retrofits account for around 25% of demand, as existing pickling lines, nitric acid plants and chemical facilities upgrade to meet tighter emission limits, address complaints about brown plumes or comply with stricter workplace exposure limits. Upgrades, such as adding ozone injection to existing wet scrubbers at refineries and industrial plants, adding oxidation stages or improving wastewater treatment, account for about 10%. Services, including maintenance, oxidant and reagent supply, ozone generator servicing, performance testing and monitoring, account for around 10% of activity and provide steady revenue. Lead times for custom systems can range from six to eighteen months, so project pipelines provide visibility for suppliers. Chinese suppliers are increasingly competitive in domestic projects and expanding into Southeast Asia, while Western suppliers focus on complex and high-specification systems. Government incentives for domestic chip and battery manufacturing in the United States, Europe, Japan and India underpin the new-build pipeline through the late 2020s. Semiconductor customers typically require strict uptime guarantees and rapid service response, so local service presence is a key competitive factor. Suppliers with installations at leading foundries gain reference credibility for new projects.

Asia-Pacific accounts for around 50% of NOx scrubber demand, driven by semiconductor, electronics, chemical and metal processing industries, while North America and Europe are significant markets. Asia-Pacific accounts for around half of global NOx scrubber installations, led by Taiwan, South Korea, Japan and China, which host most of the world's semiconductor fabs and large electronics, chemicals and stainless steel industries, and by India's growing chemicals and metals sectors. Chinese environmental regulations and emission enforcement drive demand in chemicals and metal finishing. North America accounts for about 25%, with new semiconductor fabs supported by the CHIPS Act in Arizona, Texas, Ohio and New York, refinery FCC scrubbers with ozone injection, and chemical and metal processing, with suppliers such as Tri-Mer, CECO and Envitech. Europe accounts for about 20%, with chemicals, metal processing, nitric acid production and new semiconductor investments supported by the EU Chips Act, and strict industrial emission standards under the revised Industrial Emissions Directive. The Middle East, Latin America and Africa have smaller markets linked to chemicals, refining and metals.

• 2026 – AI chip demand sustains semiconductor fab construction: Continued construction of semiconductor fabs for AI chips in Asia and the United States supported demand for NOx and acid gas abatement scrubbers.
• 2026 – Energy price increases raise ozone and scrubber operating costs: Higher electricity and energy prices following the 2026 Iran war increased operating costs for ozone-based NOx scrubbing systems.
• August 2024 – EU revised Industrial Emissions Directive enters into force: The revised directive broadened coverage and tightened permitting for industrial installations, supporting investment in process NOx control.
• 2024 – Battery materials processing expands NOx abatement needs: Growth in battery cathode and precursor production, which uses nitric acid and nitrates in some processes, increased demand for NOx scrubbing.
• September 2023 – EU Chips Act enters into force: The EU Chips Act supported new semiconductor manufacturing investment in Europe, creating demand for fab abatement systems.
• August 2022 – US CHIPS and Science Act signed: The CHIPS Act funded new US semiconductor fabs, increasing demand for process exhaust abatement, including NOx scrubbers.

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

Aspects covered in this report
• Global NOx Scrubber Market with its value and forecast along with its segments
• Various drivers and challenges
• Ongoing trends and developments
• Top profiled companies
• Strategic recommendation

By Technology
• Oxidation-Absorption Wet Scrubbers
• Ozone-Based Low-Temperature Oxidation
• Semiconductor Abatement Scrubbers
• Packed and Spray Tower Scrubbers

By Application
• Nitric Acid and Nitrate Production
• Metal Pickling and Etching
• Semiconductors and Electronics
• Refinery FCC Units
• Pharmaceuticals and Fine Chemicals
• Battery Materials
• Combustion and Other Sources

By Scale
• Central Industrial Scrubbers
• Point-of-Use Scrubbers
• Packaged and Modular Scrubbers

By Installation
• New Installations
• Retrofits
• Upgrades
• Services