Processing unit

The use of tracers enables efficient and reliable measurements of oil, gas and water flow in industrial process units and pipe line systems under production conditions thus fundamentally being non-destructive testing methods. Typical problems which can be efficiently assessed by tracer studies include ... 

CPU (central processing unit) the part of a computer that does mathematical and logical operations. 

A computer must communicate with a variety of peripheral devices (keyboard, mouse, printer, mass spectrometer). A central processing unit (CPU) controls the flow of information to each, rather like a choreographer directing complicated dance routines. 

Fig. 16. Static mixers which provide a contiauous mixing and processing unit with a nonmoving part. These static mixers can be easily installed in new and...

The butane-containing streams in petroleum refineries come from a variety of different process units consequently, varying amounts of butanes in mixtures containing other light alkanes and alkenes are obtained. The most common recovery techniques for these streams are lean oil absorption and fractionation. A typical scheme involves feeding the light hydrocarbon stream to an absorber-stripper where methane is separated from the other hydrocarbons. The heavier fraction is then debutanized, depropanized, and de-ethanized by distillation to produce C, C, and C2 streams, respectively. Most often the stream contains butylenes and other unsaturates which must be removed by additional separation techniques if pure butanes are desired. 

Many filters in chemical process units are either changed very rarely or are back-flushed automatically so there is hardly any exposure. Some filters, however, require frequent manual changing or cleaning and significant exposure may occur unless operators foUow the proper procedure. The filter container should be drained of any toxic material and then flushed and purged as needed so that when it is opened there is only minimal exposure. Zero exposure is difficult to achieve in situations where a disposable paper filter cartridge may retain and slowly release a material that cannot be removed by multiple flushes and purges. 

Gas and Hquid dehydrators employing molecular sieves provide product gas streams of <0.1 ppmv water and product Hquid streams routinely to <10 ppmv water. AppHcable pressures range from less than one to several hundred times atmospheric pressure. Temperatures range from subzero to several hundred °C. Processing units range in capacity from as Httle as 10 m /h to as much as 10 mr /d in multiple-train units. 

Industrial production of copper phthalocyanine usually favors either the phthaUc anhydride—urea process (United States, United Kingdom) (1,52,53) or the (9-phthalodinitrile process (Germany, Japan) (54,55). Both can be carried out continuously or batchwise in a solvent or bake process of the soHd reactants (56). 

Development of a preliminary layout requires the following information (/) process flow diagrams (2) plot limits (J) process unit rough area... 

Figure 12 shows the plan and elevation views of a process unit piping (9). A dmm is supported off the piperack. Heat exchangers are located far enough back from the support columns so that they are accessible and their shell covers can be removed. Pumps are located underneath the piperack, but sufficient room is provided for maintenance equipment to access the motors and to remove the pump if necessary. The motor is always oriented away from the process equipment and located on that side of the piperack. Instmment valve drops are shown supported from the columns. The instmment trays themselves mn on the outside of the support columns. Flat turns are only made from the outside position of the piperack. Nozzle-to-nozzle pipe mns are made whenever possible. Larger lines are located on the outside of the piperack. Connections to nozzles above the rack are made from the top... 

Fig. 7. Schematic of a self-contained plasma processing unit designed to continuously plasma-treat and impregnate with resin, reinforcing fibers for enhanced composite strength. The unit can also be used to plasma-treat wires to be coated or treated for improved adhesion. Throughput speeds of over...

Flow-sheet models are used at all stages in the life cycle of a process plant during process development, for process design and retrofits, and for plant operations. Input to the model consists of information normally contained in the process flow sheet. Output from the model is a complete representation of the performance of the plant, including the composition, flow, and properties of all intermediate and product streams and the performance of the process units. 

The computer effort required to get a solution to a simulation problem is important because, ia the cases of optimization of desiga and dynamic simulation for control, many simulator mns must be made. At times the models of process units are simplified and often linearized to speed up the convergence. 

Banked Memory. Another characteristic of many vector supercomputers is banked memory. The main memory is usually divided into a small number of electronically separate banks. A given memory bank can absorb or supply operands at a much slower rate than the rate at which the central processing unit (CPU) can produce or use data. If the data can be spread across multiple memory banks, the effective memory bandwidth, or rate at which memory can absorb or supply data, is increased. For example, if a single memory bank can supply one operand every 16 clock cycles, then 16 memory banks would enable the entire memory subsystem to deflver one operand per clock cycle, assuming that the data come sequentially from different memory banks. 

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