Thursday, 1 November 2018

Sintered porous screens for sparging applications



Sintered porous mesh media is capable of a long filter service life through years of continuous use. The solids state diffusion bonding of the sintered porous metal media eliminates tear, fatigue and breakthrough problems usually of the other media. It is tensile strength makes it suitable for high differential pressures. The whole metal construction seams can withstand high temperatures.

Sintered metal media can be fabricated in diverse cartridge configuration for retrofit. Besides to stainless steel 316L, other alloys are available to meet special requirements like high temperature or chemical resistance. It’s uniform porosity results in high retention efficiency. Sintered porous mesh media has performed a major role from the pretreatment of waste streams, to a finishing stage filter for final solids elimination.

Sparging applications
Gas-liquid contacting is an essential process operation in wastewater treatment. Sintered metal spargers offer a new dimension in efficient and economical performance. Besides to rugged construction and corrosion resistant property, the porosity considerably enhances mass transfer. Sintered metal screens have had proven success in applications including adsorption and direct steam injection that are found in wide range of industries.

Sintered mesh media is available as static or dynamic spargers. Static sparging relies of the gas pressure to develop the bubble and self release in the liquid. In dynamic cases, the bubble is developed at the surface and is sheared off by high fluid velocity. There are two types of dynamic spargers, intrusive and non-intrusive. Intrusive spargers are inserted in a pipeline, while non-intrusive spargers are a shell and tube design installed into the pipeline. Non-intrusive sintered metal spargers were compared with traditional tank sparging under both agitated and non-agitated conditions. 
Absorption by using sintered metal media more than doubles, increasing gas savings by 65 to 74%.
Standard or traditional tank methods of introducing gas include: bubble caps with large bubble propagation and low oxygen uptake; spraying and surface agitation that are energy intensive and inefficient and drilled pipe spargers which produce large, quickly rising bubbles with low contact area and poor mass transfer.

Applications vary by using sintered porous metal spargers as mixers in wastewater settling tanks, or for steam injection to heat water. The energy savings benefit of using sintered metal spargers for steam injection when compared with a drilled pipe distribution. Other sparging applications that would benefit using sintered metal media are:

·         Oxygen injection for BOD and COD
·         Oxygen stripping
·         pH adjustment and control- neutralizing alkaline solutions
·         Elimination of steam hammers
·         Volatime stripping- elimination of volatile organic compounds from waste streams
·         Adding O2 and O3 to purify and supply oxygen to municipal water supplies
·         Ozone treatment
Sintered mesh screens proved to be an economical solution to decrease chemical waste problems in wastewater treatment plant.

No comments:

Post a Comment