What Is a Wet Scrubber, and How Does It Work?
A wet scrubber, or wet scrubber system, is a type of pollution control equipment that is designed to remove harmful gases and particulates from industrial exhaust streams. It works by funneling the exhaust stream through the bottom of a packed tower and then it passes through an engineered packing, where a solution from specialized nozzles is sprayed countercurrent to the exhaust stream flow. This solution can often be water, especially when the stream is primarily dust or dust like particles. When the waste gas has lower solubility, chemicals are usually added to the solution. These chemicals are carefully chosen to react with the compounds released in the exhaust stream, which are generally acidic gases. After the exhaust stream is treated, the gases are released, clear of the dangerous gases, VOCs, and / or particles. The clean air is then released into the atmosphere; although it is clear of VOCs and dangerous compounds, the gas released from the scrubber often looks like steam. This is because it is heavy with H2O vapors, which may be visible in the air at the time of release.
Packed, dry and wet scrubbers are used to treat or clean the following lists of chemicals from a process exhaust air stream, with ammonia being the most popular:
- Ammonia
- Chlorine
- Hydrochloric Acid
- Chlorinated Silanes
- Sulfur Dioxide
- Hydrogen Sulfide
- Boron Trifluoride
- Amines
Why Choose a Wet Scrubber?
- Can handle high temperature streams
- Versatile
- Can handle very moist streams
- Smaller space requirements
- Can be retrofitted into current equipment (in some cases)
- Provides cooling of heated gases
- Higher sulfur dioxide removal capabilities than other equipment options
- Lower cost of purchase
- Can remove gases and particulates in a single unit
- Able to neutralize highly corrosive gases and dusts
- No temperature limits with the use of heat reduction options
- Can handle highly flammable dusts, with very little risk of explosion, when properly designed and operated
- Several customizable options, based on specific output and applications, often allowing for a reduction in cost
- Eliminates as much or more than 99% of dangerous gases, which meets all EPA requirements for MACT, RACT, BACT, and LAER
Possible Disadvantages:
- Higher risk of corrosive issues
- Must have protection again freezing temperatures
- Disposal of waste can incur higher costs
- The chemicals collected may be too contaminated to be recycled in any way
Features & Options:
- Competitive packages including instrumentation and controls, skid mounting of equipment, H2O storage tanks, metering pumps, and installation
- Vertical and horizontal configurations
- Efficiencies up to 99.99%
- Capacities of 50 to 75,000+ SCFM
- Cross-flow and counter-flow options
- Custom designed systems
- Options to be retrofitted with current equipment
- Faster commissioning time
- Continuous monitoring with Gulfstar
- In-house designed and manufactured control panels
- Sized system process fans
- Portable options and sizes available
Wet vs Dry Scrubber
Both types of scrubbers perform the same basic function – removing dangerous particles from industrial gas streams. However, how they do it is slightly different. As their names indicate, a wet scrubber uses a solution, generally water or water based, to saturate the particulates and compounds in the exhaust stream, to weigh them down, and remove them from the gases. A dry scrubber does not saturate the particles; a dry scrubber uses dry reagents, that come into contact with the polluted stream, that then react, and either neutralize the dangerous compounds, or absorb them into a different, less harmful, substance.
Commonly used in these industries:
- Asphalt processing
- Pharmaceuticals
- Oil & Gas
- Landfills and Biogas
- Coaters
- Textile Processing
- Tar Removal
- Curing ovens
- Vinyl Manufacturing
- Acid mist control
- Fertilizer Manufacturing
- Wastewater treatment
- Steel Processing
- Electronics
- Food processing
- Cocoa Processing
- Nuclear Waste filtration
- Printing
- Precious metal recovery
- Etching
- Wood Products
Gulf Coast Environmental Systems offers multiple design solutions to best fit the operational parameters of its customers. In some cases, the desire is for a lower capital investment for a higher operating cost for those systems that do not need to run continuously, or the need may be for a slightly higher capital investment with a lower operating cost for those systems that do need to run continuously. The designs include single-stage solutions, as well as multi-stage solutions. GCES also offers complete integrated solutions with other air purification systems, such as thermal oxidizers, carbon adsorption systems, or filtration packages. Gulf Coast Environmental Systems is a single source solution for highly durable and efficient venturi and packed bed scrubbers.
Are you considering a dry scrubber? Click here!