Control concept

Fig. 25-3. Bubble concept. This pollution control concept places an imaginary bubble over an entire industrial plant, evaluating emissions from the facility as a whole instead of requiring control point-by-point on emission sources. Numbers represent emissions from individual sources, some of which can be fugitive sources, and from the entire industrial plant. Source Drawing courtesy of the Chemical Manufacturers Association.

Control of stationary sources of air pollution requires the application of either the control concepts mentioned in Chapter 28 of the control devices mentioned in Chapter 29. In some cases, more than one system or device must be used to achieve satisfactory control. The three general methods of control are (1) process change to a less polluting process or to a lowered emission from the existing process through modification of the operation,... 

Many of the inherently safer design aspects discussed here appear in Guidelines for Safe Automation of Chemical Processes (CCPS, 1993b). It makes excellent reading for greater depth and treatment of inherently safer/process control concepts. 

The process flow diagram, or PP D. is a pictorial description of the process. It gives the basic processing scheme, the basic control concept, and the process information from which equipment can be specified and designed. It pror ides the basis for the der elopment of the P l diagram and also serves as a guide for the plant operator. The process flow diagram usiuilly includes... 

Digital computers, however, can do some things the analog equipment cannot. They offer the opportunity of using more advanced control concepts. These are not necessary for 90% of the processes, but they can increase production and reduce waste for some hard-to-manage processes. For multiproduct plants, direct digital... 

Traditionally the PERT diagram did not involve costs, but in the early 1960s a plan called PERT/Cost was developed that was similar to the cost-control concepts of CPM. Some authors claimed they were now essentially the same. PERT/Cost involves obtaining one cost for each activity. If the expected time were,the same as the normal time, the procedure for cost control would be the same as for a CPM system. The PERT system can also be easily adapted to the method presented for speeding up projects (crashing). The remarks made previously about scheduling and obtaining time estimates apply equally well to PERT and CPM. 

Having explained the evolution of the peptide controls concept, the remainder of this chapter will describe the technology for creating peptide controls and review the data regarding their performance and applicability to IHC laboratory testing controls. 

Sketch a control concept diagram that includes alt valve actions and the following control strategies ... 

The last decade has seen the development a several control concepts that are based on using a model of the process as part of the controller. Most of these methods use Laplace or z-transform representations of the process, which we are not yet ready to handle. After our Russian lessons have been completed, we will discuss some of these. 

SJii. Sketch a control concept diagram for the distillation column shown below. The... 

The distillation column sketched in Fig. P8.ll has an intermediate leboiler and a vapor sidestream. Sketch a control concept diagram showing the following control objectives ... 

Hot oil is heated in a furnace in three parallel passes. The oil is used as a heat source in four parallel process heat exchangers. Draw a control concept diagram that achieves the following objectives ... 

The similarity between DMC and MAC has been formalized that formalism has been labeled the IMC structure. Garcia and Morari [42] produced the seminal work on IMC, summarizing DMC- and MAC-based results, developing the structure illustrated in Figure 9.1, and acknowledging that inferential control concepts [43] motivated the IMC structure. 

Fig. 11-Conroe Field Unit computer production control concept.

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