316L Stainless Steel Alkali Scrubber Tower

Product Overview

The 316L stainless steel alkali scrubber tower is a wet neutralization vessel used to remove acidic pollutants from industrial exhaust gas. It is also called an alkali washing tower, caustic scrubber, acid gas scrubber, alkaline spray tower or neutralization tower.

Exhaust gas enters the tower from the bottom or side and flows upward through the spray and packing section. Alkaline absorption liquid such as NaOH or Na₂CO₃ solution is sprayed from the top, forming a liquid film on the packing surface. Acidic components such as HCl, SO₂, HF and acid mist are neutralized through gas-liquid contact, and the purified gas passes through a demister before discharge.

316L stainless steel contains molybdenum, which provides better resistance to pitting corrosion, crevice corrosion and chloride ions than 304 stainless steel. This makes it suitable for wet scrubbing conditions where acid mist carryover, high humidity, chloride-containing media or long-term corrosive operation are present.

Why 316L Stainless Steel Alkali Scrubber Tower

Alkali scrubber towers are mainly used for acid gas neutralization, but the tower body, spray section and circulation system are often exposed to wet corrosive environments. 316L stainless steel offers improved resistance to chloride ions and wet acid mist compared with 304, while maintaining good weldability and structural strength.

The tower body provides higher mechanical stability than plastic or FRP scrubbers, especially for larger diameters, taller towers and continuous operation. The smooth inner surface helps reduce scaling, improves liquid distribution and supports stable neutralization efficiency over long service periods.

Structure & Working Principle

The alkali scrubber tower is a vertical cylindrical vessel made of 316L stainless steel, with gas inlet, gas outlet, inspection door, drain connection and supporting structure. Exhaust gas flows through the tower while alkaline liquid is circulated by a pump and sprayed through nozzles.

Inside the tower, the packing layer increases gas-liquid contact area and improves absorption efficiency for HCl, SO₂, HF and other acidic gases. The demister section removes entrained droplets from purified gas to reduce carryover and downstream corrosion. The circulation tank collects alkaline liquid for reuse, with optional pH monitoring and automatic dosing system to maintain stable neutralization performance.

Material Selection Guidance

316L stainless steel is recommended when the alkali scrubber treats acid gas with chloride ions, wet acid mist, high humidity or long-term corrosive operation. It provides better reliability than 304 in conditions where chloride-induced pitting or crevice corrosion may occur.

For mildly corrosive and low-chloride acid gas, 304 stainless steel may still be a cost-effective option. For severe chloride corrosion, high salt accumulation or long service life requirements, 2205 duplex stainless steel can be considered. Material selection should be based on acid gas composition, temperature, humidity, chloride concentration and expected service life.

Typical Specifications

The tower is manufactured from 316L stainless steel, with vertical alkali scrubber or alkali washing tower configuration. Diameter is typically customized between 800 mm and 4000 mm, and height is determined according to packing height, spray stages and site conditions. Wall thickness is generally designed between 2 mm and 4 mm depending on diameter, structural load and process requirements.

Internal parts include packing, spray nozzles, demister, circulation pump, alkali dosing system, piping and supporting structures. Exact dimensions, number of spray layers, packing type and connection configuration should be determined according to gas volume, acid gas concentration, temperature, humidity and installation conditions.

Typical Applications

316L stainless steel alkali scrubber towers are widely used in chemical plant acid gas treatment, electroplating and metal surface treatment exhaust, pickling line HCl and HF gas absorption, semiconductor and electronic manufacturing acid gas neutralization, pharmaceutical and food industry exhaust gas treatment, waste incineration flue gas washing, metallurgical and sintering flue gas pretreatment, as well as wet desulfurization polishing systems. They can also be arranged upstream of WESP systems, activated carbon adsorbers or RTO units to reduce acid mist, dust and moisture load before downstream polishing.

Manufacturing & Company Strength

Wuxi Xinchangyuan Equipment Manufacturing Co., Ltd. specializes in the design and manufacture of stainless steel alkali scrubber towers, absorption towers, spray towers, wet scrubbers, wet electrostatic precipitators, anode modules and anode tube bundles. Our facility is equipped with plate rolling, laser cutting, CNC forming, automatic welding, surface treatment and module assembly capabilities, supporting both standard and customized stainless steel process equipment for industrial exhaust gas treatment.

We provide engineering support from material selection and structural design to fabrication, assembly and installation guidance. Each alkali scrubber tower is manufactured according to project gas composition, acid gas load, temperature, corrosion level and site layout. Our team can integrate alkali scrubber towers with wet electrostatic precipitators, demisters, circulation systems and exhaust gas purification lines, helping industrial customers achieve stable emission performance and reliable long-term operation.

FAQ

What is a 316L stainless steel alkali scrubber tower used for?
It is used to neutralize and remove acidic pollutants such as HCl, SO₂, HF, acid mist and other acid gases from industrial exhaust gas through alkaline wet scrubbing.

Why choose 316L instead of 304 for alkali scrubbers?
Although the scrubbing liquid is alkaline, the wet environment may contain chloride ions, acid mist carryover or corrosive condensate. 316L provides better resistance to chloride-induced pitting and wet corrosion than 304.

Can the alkali scrubber tower be customized?
Yes. Tower diameter, height, wall thickness, packing type, spray layers, demister and alkali dosing system can be customized according to actual process conditions.

Can it be used together with a WESP system?
Yes. An alkali scrubber tower can be arranged upstream of a WESP to reduce acid mist, dust and moisture load, helping the downstream polishing system operate more stably.

Tel：+86 13656199922

Phone：+86 13656199922

Email：wxxcysbzzyxgs@163.com

Address：35-3 Yanqiao Road, Yanqiao Street, Huishan District, Wuxi City, Jiangsu Province, China