Multi-purpose reactor

Whenever a new reaction is introduced into a multi-purpose reactor, an assessment of the adequacy of the relief system needs to take place. If necessary, the relief system will need to be modified before the new reaction begins to be used. At the same time, the adequacy of the new relief system for air other reactions that are performed in the reactor will need to be checked, especially if the modification involves an increase in relief pressure due to a higher operating pressure for the new reaction. 

It may be possible to minimise the time spent on relief system assessment and design if the basis of safety for a multi-purpose reactor can be changed to prevention rather than emergency pressure relief. For example, if it can be arranged for all the reactions to operate in semi-batch mode with no significant reactant accumulation, then the use of a trip system of sufficient integrity may provide a suitable basis of safety. (This may not always be possible.)... 

Change management is particularly important for multi-purpose reactors. When beginning a new campaign, it will1 be necessary to check that all modifications required for safe operation of the new reaction have been implemented. This may sometimes include the installation of different relief devices with a new relief pressure. 

At a multi-purpose reactor, shutters will also be required in order to stop the beam without shutting down the reactor. 

Technologies of modular pressurized water reactors for Russian nuclear ships Well established the operating experience of shipboard multi-purpose reactors exceeds 6000 reactor-years. 

The realization of complete bench-scale micro reactor set-ups is certainly still in its infancy. Nevertheless, the first investigations and proposals point at different generic concepts. First, this stems from the choice of the constructing elements for such set-ups. Either microfluidic components can be exclusively employed (the so-caUed monolithic concept) or mixed with conventional components (the so-called hybrid or multi-scale concept). Secondly, differences concerning the task of a micro-reactor plant exist. The design can be tailor-made for a specific reaction or process (specialty plant) or be designated for various processing tasks (multi-purpose plant). 

Figure 5.29 Special-type multi-purpose micro devices and mixing tee used for investigation of CO2 absorption. Comparison of their reactor performance as a function of the residence time. Micro bubble columns ( ) 1100 pm x 170 pm, (A) 300 pm x 100 pm and (T) 50 pm x 50 pm Interdigital mixer ( ) (40 pm) caterpillar mixer (A) (850 pm ramp) mixing tee (0) (1 mm) [5],...

Carlsson, L., Sandgren, B., Simonsson, D., and Rihousky, M., Design and performance of a modular, multi-purpose electrochemical reactor./. Electrochem. Soc. 130,342-350(1983). 

For multi-purpose vessels there will be a much larger number of possible relief scenarios. The worst case can be found using the methods above, but the process may be more time-consuming because many more possible scenarios are likely to be identified. Sometimes different relief systems may be specified for the different reactions that are carried out in a reactor, and the bursting disc must be changed to the correct one at the beginning of a campaign. A robust procedure is clearly needed to ensure that this occurs. -... 

This type of incident is difficult to predict. Nevertheless, by using a systematic approach to hazard identification it should become clear that any water entering the reactor could lead to an explosion. Therefore when changing some parts of the equipment, even if they are not directly involved in a given process, especially in multi-purpose plants, one should at least consider possible consequences on the safety parameters of the process. 

The inquiry showed that the process was operated in the parametric sensitive range. As the batch size was increased to 1100 kg, the maximum temperature during the holding phase increased to 170 °C. Moreover, the thermometer had a range of 200 °C from -30 °C to +170 °C, because the reactor was multi-purpose equipment also equipped with a brine cooling system. Thus, the technical equipment was not adapted to the process conditions. 

Typical performance is a selectivity higher than 90% at a conversion in the 50-90% range, mainly depending on the type of substrate. Substituted pyridines yield better selectivities at high conversion than the equivalent alkylaromatics. The nature and position of the substituents in substituted alkylaromatics also play an important role in determining selectivity and activity. The commercial application of this technology is mainly hindered by the relatively small plant necessary for these products as compared to full-scale processes. The further implementation of the process of alkylaromatic catalytic ammoxidation would thus require the development of multi-purpose small-size continuous plants using small fluidized bed-reactors (to better control temperature and allow easier substitution of the catalyst). 

The Lurgi multi-purpose gasifier (MPG) is an entrained flow gasifier nsed for liquid wastes (tars, oils, solvents, emulsions and also the tars and oils generated by the fixed bed reactors, and even slurries). 

Multi- purpose, extends applications of the Heating Reactor,... 

The problem is often compounded because batch reactors are frequently multi-purpose rather than dedicated to one process. A single batch reactor may be used to carry out many different chemical processes, and for each reaction it is necessary to ensure that a runaway cannot occur — for example, by allowing the heat of reaction to exceed the cooling capacity of the vessel. 

A multi-purpose mast manipulator, based on the CEGB Oldbury Mk III design modified to accommodate the Calder/Chapelcross space restrictions, has been built by Taylor-Hitec. The manipulator is pneumatically powered and comprises a two-section mast (because of reactor building space limitations), an arm and a knuckle sections, with the basic design parameters being shown schematically in Figure 9. The movements are controlled from a central console which has TEACH-AND-REPEAT and RE-TRACE facilities. There are two independent... 

A clear hurdle for the application of a microstructured reactor in a multi-product or multi-purpose environment is that a relatively large part of the fine chemical processes contain solids. Some newer reactor concepts seem to be able to handle solids better than the early microreactors but this still needs to be developed further. 

The HR-200 is a kind of small sized reactor for heating supply initially and it is used also for multi-purpose applications. Some other work have been or will be finished by INET in order to improve NHR s economic benefits and load factor. These studies mainly include as the follows ... 

Use of well-proven special heavy-water equipment and systems from the heavy-water reactor power plants MZFR (multi-purpose-research reactor, Karlsruhe, FRG, 58 MW) and Atucha I (Argentina, 367 MW(e)). 

The FRDB refleets stages that have led to the physieal and teehnological substantiation of fast reactor designs (from the first multi-purpose demonstration plant BN-350 to the EFR commercial power plant projeet). It eomprises the numerous R D findings that form the basis of fast reactor technology and... 

The SVBR-75/100 (ANNEX XIX) is a modular multi-purpose lead-bismuth cooled fast reactor of 75 to lOOMW(e), offering a refuelling interval of 6 to 9 years. The design is backed by the experience of 50 years in design and operation of reactor installations with lead-bismuth coolant for nuclear submarines, available in the Russian Federation. Specifically, the marine prototypes of the SVBR-75/100 have achieved a total of 80-years of operating experience. 

The ABV design was developed using operating experience of VVER type reactors and recent achievements in the field of nuclear power plant safety. The main purpose of the project is the creation of small multi-purpose power sources based on proven marine reactor technologies, providing easy transport to the site, rapid assembly and safe operation. 

The unit power, the design and operating characteristics of the ABV reactor installation offer an opportunity to create a compact power unit meeting the requirements for simple and safe operation and multi-purpose applications. 

Steam generators, control and protection system (CPS) drives, pressurizer system, reactor installation systems, biological shielding and other systems — the technologies widely used in NPPs with pressurized water reactors and shipboard reactors of the Russian nuclear fleet Widely used reactor technologies the operating experience of multi-purpose shipboard reactor installations exceeds 6000 reactor-years... 

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