AIR STRIPPING OF WATER
The growing demand placed on the world’s water, in combination with more stringent water quality regulations, have placed unprecedented demands to provide safe, reliable and aesthetically pleasing drinking water. Air stripping is an effective way of removing volatile organic chemicals (VOCs) from contaminated water and is commonly used for this application. Air stripping systems mix air with a water supply with the goal to generate the largest possible air-water contact area so that VOCs and dissolved gases, such as radon and hydrogen sulfide, will move from the water to the air. In addition to removing VOCs, air stripping is primarily used for removing oxidizing contaminants such as iron and manganese, improving taste, or removing odor. Air stripping is an EPA Best Available Technology (BAT) for some VOCs including benzene, toluene, xylene, tri/tetrachloroethylene, trihalomethanes, vinyl chloride and many others.
REMOVING UNWANTED ENTRAINED OR DISSOLVED GASES PROFICIENTLY
Mazzei is renowned as a leader in mixing and contacting technology, and the Mazzei GDT™ contacting process has proven to be extremely efficient in utilizing this technology in air stripping applications. The GDT contacting process dynamically transfers gases into solution while removing unwanted entrained or dissolved gases.
The GDT contacting process draws air into the pressurized water to be treated via high efficiency Mazzei venturi injectors. The dynamic mixing that takes place at the injector efficiently transfers air into solution and strips unwanted materials. The objectionable materials are removed by the patented Mazzei degas separator before they can go back into solution. Staged recirculation within the GDT contacting system allows for enhanced removal rates of the most difficult contaminants.
The GDT contacting process, either independently or in conjunction with other technologies, is an efficient and dependable means of treating water. It offers water treatment professionals the benefits of design flexibility for any flow rate. In addition to the technological benefits, the GDT contacting process features a small footprint and low capital, installation and operating costs in an easy to install, non-fouling pressurized system which provides the user with the ability to contain and treat process off gas.
EXAMPLES OF STRIPPING APPLICATIONS WHICH BENEFIT FROM THE GDT CONTACTING PROCESS
- Acid Water Treatment — CO2 Removal
The ratio of carbon dioxide to bicarbonate ion directly affects the pH of water — the higher the ratio the more naturally acidic the water. Due to its corrosive nature, acidic water causes corrosion of piping materials, and corrosion is the primary cause of elevated lead/copper levels in water distribution systems. The GDT Contacting Process provides corrosion control by stripping CO2 from solution and lowering the CO2/HCO3
- Methane Removal
Methane is easy to strip out of water. With Mazzei®Venturi Injectors — part of a GDT Contacting System — more than 80% removal can be achieved.
- Radon Reduction
The GDT Contacting Process is ideally suited to strip radon from water due to the high Henry’s Law constant and pressurized operational design.