Contactors system

Method A packed-bed throwaway system to remove organic pollutants from oily waste stream. System component A contactor system, and a pump station designed for a contact time of 30 min and hydraulic loading of 162 L/min/m2 (4gpm/ft2). 

Generally, a distinction can be made between membrane bioreactors based on cells performing a desired conversion and processes based on enzymes. In ceU-based processes, bacteria, plant and mammalian cells are used for the production of (fine) chemicals, pharmaceuticals and food additives or for the treatment of waste streams. Enzyme-based membrane bioreactors are typically used for the degradation of natural polymeric materials Hke starch, cellulose or proteins or for the resolution of optically active components in the pharmaceutical, agrochemical, food and chemical industry [50, 51]. In general, only ultrafiltration (UF) or microfiltration (MF)-based processes have been reported and little is known on the application of reverse osmosis (RO) or nanofiltration (NF) in membrane bioreactors. Additionally, membrane contactor systems have been developed, based on micro-porous polyolefin or teflon membranes [52-55]. 

Takeuchi, M., T. Washiya, H. Nakabayashi, et al. 2005. Engineering Test of Stripping Performance by Multi-Centrifugal Contactor System for Spent Nuclear Fuel Reprocessing. 13th International Conference on Nuclear Engineering, May 16-20, Beijing, China. 

Washiya, T., M. Takeuchii, H. Ogino, and S. Aose. 2005. Development of Centrifugal Contactor System in JNC. Proceedings of GLOBAL 2005, October 9-13, Tsukuba, Japan. 

D.T. Tsou, M.W. Blachman and J.G. Davis, Silver-facilitated Olefin/Paraffin Separation in a Liquid Membrane Contactor System, Ind. Eng. Chem. Res. 33, 3209 (1994). 

Figure 20.6 An integrated reverse-osmosis-membrane contactor system for boron removal (From Ref. [31].)...

Membranes are polymeric microporous materials in hollow-fiber or flat-sheet configurations. The membrane properties control the contactor and the membrane contactor system performance and economy. The most important membrane properties are ... 

Figure 22.4 Schematic diagram showing how membrane contactors systems operate.

Figure 22.5 General layout of a membrane contactors system.

In Figure 22.8 the layout of the membrane contactor system is described. As liquid desiccant a CaCl2 solution has been used. The demonstration runs lasted more than 450 hours. 

The air temperature of the intermediate cell is assumed to be equal to 15 °C. This intermediate cell is dehumidified by the membrane contactor system placed at the evaporator inlet. The dehumidified air is driven to an air curtain at the top of the door separating the intermediate cell from storage cell. The heat load of the system and the air circulation ratio are assumed to be constant. The temperature of CaCl2 solution at the inlet of the membrane contactor is assumed to be equal to the indoor IC air temperature. The following parameters have been measured ... 

Profile or footprint of membrane contactor systems are small fit into existing building no additional structure needed... 

As mentioned in Table 2.2, one unique feature of membrane contactors is the ability to operate without the aid of gravity. This, along with the advantage of smaller sizes for contactor systems, has led to the interest in possible use of this technology in microgravity and confined spaces such as spacesuits, manned spacecrafts, and space station. Primary apphcations are (1) separating gas and liquid phases in microgravity and (2) removal of unwanted gas species from liquids [62-64]. 

Trains of 3 large contactors in series 9-Contactor system expandable to 16 contactors... 

A photo of a small-scale membrane contactor system that could be used to simultaneously carbonate and deoxygenate water is shown in Figure 2.14. This is accomplished by passing CO2 gas stream under pressure as a sweep on the lumen side of the contactor while water flows through the shell side. Water absorbs CO2 under pressure and becomes carbonated while the presence of excess CO2 gas creates a driving force for removing dissolved oxygen from the water. 

Tsou DT, Blachman MW, and Davis JC. Silver-facilitated olefin/paraffin separation in a hquid membrane contactor system. Ind. Eng. Chem. Res. 1994 33 3209-3216. 

The term contactor systems present only membrane devices, mosdy hollow-fiber, but not processes. The membrane in a contactor acts as a passive (not selective) barrier and as a means of bringing two immiscible fluid phases (such as gas and hquid, or an aqueous hquid and an organic hquid) in contact with each other without dispersion. The phase interface is immobihzed at the membrane pore surface, with the pore volume occupied by one of the two fluid phases that are in contact. Contactor devices are used in many of the above-mentioned BLM systems (HLM, HFCLM, HFLM, FLM, pertraction, membrane-based extraction, MHS) as construction units. Sometimes, selective hydrophobic, hydrophihc, or ion-exchange membranes are used as barriers for additional selective separation in the devices similar to contactors. 

Korikov AP, Sirkar KK, Otto H. Membrane gas permeance in gas-liquid membrane contactor systems for solutions containing a highly reactive absorbent. J Membr Sci 2005 246 27-37. 

The extraction of metals based on a membrane contactor system with conventional solvents is a process widely studied using different configurations, extractants, and extraction solvents. One of the upcoming applications of membrane contactors is supercritical extraction. This process is called porocritical extraction. Porocritical process or porocritical extraction is a commercial supercritical fluid extraction (SFE) technique that utilizes an hollow fiber membrane contactor (HFMC) to contact two phases for the purpose of separation. As an improvement, the extraction of Cu + from aqueous solutions by means of dense gas extraction was achieved by using a hollow fiber membrane contactor device [7]. The authors... 

Teplyakov W, Okunev AY, Laguntsov NI. Computer design of recycle membrane contactor systems for gas separation. Sep PurifTechnol 2007 57 450-454. 

MCs present an alternative to more conventional contactor systems. The main advantages of MC systems over conventional column contactors are the reduction in size, the operational flexibility, elevated mass transfer rate and Unear scale-up, and the possibiUty of integration. Independent of their... 

Figure 26.3 Membrane contactor system with multiple immobilized fluid phase interfaces.

FIGURE 9.2 Resistance to the mass transport offered by the gas, membrane, and the liquid in a membrane contactor system. 

Research on Liquid Absorbent Employed in Membrane Contactor Systems... 

Among the commercially available membrane in the market, Liqui-Cel membrane, which is made from PP polymer, is extensively used in membrane contactor systems for pilot plant test. For the last 10 years, membrane contactors have been used in the diverse areas of microelectronics, pharmaceutical, power, food and beverage, industrial photographic, ink, and analytical markets [83]. Among European countries, the Netherlands is actively committed to installing and testing membrane contactor systems for capturing CO2 from flue gas (pre- and post-combustion capture). 

Its efforts can be seen through numerous collaborations between Netherlands Organisation for Applied Scientific Research (TNO) and other industrial partners. Table 9.6 summarizes the current and ongoing field tests on membrane contactor systems for various applications. 

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