Reactors unloading

Control System. The operation of the reactor unloading mechanism is electrohydraulically controlled. The power that operates the mechanism is hydraulic. The flows in the hydraulic system are governed by soleiioid-operated valves. The valve solenoids are operated by push-button switches in. the various electrical control circuits. These circuits are interlocked by pressure switches, limit switches, and relays to ensure proper sequence of... 

Practical considerations of unloading play a major role in batch-mass reactors. For "low conversion reactors, a suitably sized dump line must be chosen, based on acceptable N2 dump pressure in the reactor, or discharge pump capability, as well as consideration for limiting reaction in the line between batches. 

For a polypress reactor, control of cake sticking and provision for unloading the cakes are practical considerations which can outweigh any theoretical kinetic determinations. 

Except for those catalysts subjected to the previously mentioned conditions, which lead to irreversible transformation of the active phase and/or the support material, the HDT catalysts are regenerable [37], Through a systematic and careful procedure, the spent catalyst is unloaded from the reactor and regenerated by specialized companies. The possibility of in situ regeneration is also commercially offered and the decision, on which method would be used, is typically based on economical considerations [38],... 

Catalytic experiments. The runs are performed in a 300mL static reactor (Autoclave Engineers Model AE 300) for 15hrs under an initial 20 bar pressure with a sample weight leading to 0.U mg-atom of metal. Neither the unloaded zeolites nor the molecular clusters are active in CO hydrogenation under our experimental conditions. 

Including 20 ft2 for miscellaneous items not identified in this section, 110.3 ft2 must be rented, at an annual cost of 44,100/yr. Note that this moderately sized complex is added to an existing electronic materials manufacturing facility. Hence, no direct charges are added for infrastructure, such as non-clean room and office space. The total purchase cost, 6,492,100, provides equipment modules that require small installation costs, on the order of 1% that is, 65,000. Note also that two PECVD reactors are provided to assure uninterrupted operation when the plant is in operation, around the clock, 330 day/yr. While the robot loads and unloads one of the reactors, the other reactor is in operation. 

Safety aspects of drum storage, pellet screening, dust removal, reactor loading and unloading, and activation of process catalysts are discussed [1], and reprocessing aspects are considered, with disposal as a last resort [2], Hydrogenation catalysts introduce their own problems [3],... 

In Canadian fibre plants, personal TWAg levels were less than 1 ppm [2.2 mg/m ] for unloading, reactors, wet spinning, maintenance and cleaning and processing in 1980 (Guirguis et al., 1984). [These measurements were identified as personal TWA, by the authors. It was not clear, however, how the measurements relate to workers exposures, since they were identified by area descriptors]. 

The two broad classes of photochemical reactors are the batch processors and the continuous processors. The batch processor is simple in design, but costly in operation, because it requires the loading of the reactant, the unloading of the product and the cleaning of the reactor vessel all operations which involve human intervention. Batch processing is used as a rule in laboratory synthesis, but industrial applications prefer continuous systems for reasons of efficiency. Still, it must be accepted that batch processing will be used for many small-scale industrial syntheses. 

Figure 4.11. Section for manufacturing coated polyurethane rollers 1 - reactor for polyester 2 - batcher for modifying agent 3 - reactor-mixer 4 - batcher for diisocyanate 5 - batcher for curing agents 6 - mold for casting rollers 7 - heat chamber for solidification 8 - unloading device 9 - transporting device.

By placing vacuum at the exit of the reactor the catalyst particle could be unloaded, and using the inert gas stream at the inlet of the reactor, new catalyst can be placed. At the outlet of the reaction channel two posts 25 pm apart act as a filter to retain the catalyst particles. In addition, some channels were used to hold thermocouples or optical fibers to monitor the experimental conditions. To prevent corrosion of silicon by gaseous chlorine, the channels are covered with a silicon oxide layer of about 5 nm thickness. The reactor is capped with a Pyrex wafer [39]. A more detailed description of the reactor is given in [61]. 

A new epi reactor, the "Precision Epi 7010," has recently been introduced by Applied Materials. The unusual layout of this new system is shown in Figure 14. The central concept in this new reactor system is lower processing cost per wafer, while hopefully maintaining the same quality of epi films. The design features that lower the per wafer cost are the dual susceptor design and the use of low-frequency induction for heating. With two susceptors, one can be loaded or unloaded while the other is being processed. 

Following an experiment the reactor was unloaded and the catalyst was extracted using toluene first and then pentane. The coke content of the thus extracted catalyst was determined using Combustion Mass spectrometric Element analysis (CME). Since the total catalyst charge of the reactor was mixed at the end of an experiment, the coke data thus obtained are average data over the reactor. In other words, no coke profiles have been established by experiments. The amount of coke deposited is reported on the basis of the catalyst mass (fresh oxidic catalyst basis, the total amount of feed processed (percent weight on feed, %wof),... 

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