Adsorber system, design

Equilibrium Considerations - Most of the adsorption data available from the literature are equilibrium data. Equilibrium data are useful in determining the maximum adsorbent loading which can be obtained for a specific adsorbate-adsorbent system under given operating conditions. However, equilibrium data by themselves are insufficient for design of an adsorption system. Overall mass transfer rate data are also necessary. 

Mass Transfer Rale Consideralions - As discussed previously, the mass transfer mechanism involved in industrial adsorption processes is complex. Generally, basic physical data on the materials involved are insufficient for design. Experimental mass transfer rate data for the specific adsorbate-adsorbent system are usually required for good design. 

The main problem in the system design is the heat and vapor transport in and out of the adsorbent. Advanced heat exchanger technologies have to be implemented in order to keep up the high energy density in the storage, which would be reduced by the amount of inactive heat exchanger material. 

Global has also designed and built a dual-stage, low-temperature adsorbent desulfurizer. Sulfur in propane can exceed as much as 300-ppm compared to natural gas, which ranges from 2 to 15-ppm sulfur and it must be removed to block any poisoning of the fuel cell. The test results indicated that no sulfur compounds were present in the outlet gas of the desulfurizer. The system design uses a modular assembly and layout, including a circular hot box where the fuel cell stacks and the fuel processor are located and easily accessed. 

In AAC technologies, water is exposed to an AAC material, and metals in the water are adsorbed by the material. AAC systems can be designed and built as stand-alone units or integrated to work efficiently in concert with complementary water treatment systems designed for hydrocarbon removal, pH control, particulate removal, or electrodialysis. AAC systems can tolerate hard water (calcium and magnesium) and high temperatures (up to 200°F) without a decrease in performance. 

The sophisticated sequencing and the requirements for control of the transfer of gas streams among the adsorbers presented a challenge in control system design. Through use of solid state programmable hardware... 

Another multisyringe FI separation system design has been used in the analysis of stable and radioactive Y, using an extraction-chromatographic material containing HDEHP adsorbed on a C18 support.123 Separated samples were analyzed off-line by ICP-AES and proportional counting. This system used four syringe pumps in parallel. 

Various reactors can be used for dynamic experiments. The application of recycle reactors to the investigation of the underlying reaction networks has been demonstrated by Bennett [58], who operated a recycle reactor with the dynamic method by superimposing reactant concentration pulses on the inlet stream. To ensure that the amounts of gaseous components adsorbed on the catalyst are appreciable compared to the amounts of measurable components flowing, the ratio of the catalyst to total reactor volume was made as high as possible. A reactor system, designed for transient experiments, has been described by Bennett et al. [43]. 

Recalculate the time before breakthrough occurs, based on the following transient condition. The adsorber system is on line for one hour at the above normal design conditions when the inlet concentration of TCE rises to an average value of 2500 ppmv due to a malfunction in the degreaser process the efficiency also drops to 97.5% during this time. Assume the SAT remains the same. 

One of the objectives of a biochemical separation system design is to minimize the number of steps (Figure 1) One way of accomplishing this is to perform the separation and concentration in situ that is directly with the whole fermentation broth using solids phase adsorbents. This type of separation requires the design of an affinity bead that provides for selective product removal from the fermentation broth. 

A new system, designed specifically for diesel engines, composed of a NOx adsorbent trap coupled to a lean NOx reduction catalyst is described. The trap adsorbs NOx between 150 and 500 C which is periodically desorbed thermally by a localized exotherm generated within the catalyst from the controlled injection and oxidation of diesel fuel (always maintaining the exhaust lean). The hydrocarbon injection temperature is controlled to allow for a downstream lean-NOx Pt catalyst to reduce the desorbed NOx. Significant increases in NOx reduction are possible. 

In many solvent recovery systems, adsorption represents only one step in a complex series of chemical engineering operations. The design of a eomplete system for recovering methylene chloride and methanol from air emitted from a dryer in a resin processing plant has been described by Drew (1975). The overall solvent recovery system includes a water scrubber to remove resins and cool the air to 100°-110°F a standard 2-bed carbon adsorber unit designed for 95% solvent removal efficiency a condenser and decanter to handle the vapors that are stripped from the carbon by steam an extraction column in which water is used to remove the water soluble methanol from the methylene chloride phase a stripping column to remove dissolved methanol and methylene chloride from the waste water and a drying column to remove water from the recovered methylene chloride. These items of equipment and operations are representative of those required for complete solvent recovery systems however, each system must, of course, be tailored to the profierties of the specific solvent involved. 

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