Automation concepts

The automation concept implemented at Conroe is called computer production control (CPC).2 CPC systems are driven by a general purpose process-control computer (48-K core memory) centrally located and programmed to monitor production and equipment operations and perform oil and gas accounting. As shown in Fig. 11, the computer is connected to a supervisory control system with a computer interface unit (CIU) to provide remote data acquisition and control function capability. 

The starting point for the development of automation concepts was in analytical routine laboratories (e.g. analytical R D and quality control) dealing with high numbers of samples routinely to be analyzed by the application of standardized operation procedures [349]. In parallel, the first robot systems for research were developed and these combine the key technology of liquid handling with the movement of items through a defined space. 

Recently, Merck KGaA in Darmstadt in cooperation with AnalytiCon AG (Berlin) presented a HPLC-based Workstation (SepBox) designed for the extraction and separation of plant material in a more preparative scale which has also successfully been used for the separation of secondary metabolites from culture broths of microorganisms. On the other hand, it has been shown that automated solid phase extraction (SPE) can achieve high quality samples from cultivation of microorganisms in an easy and cost-effective manner. In the latter case modified Zymark RapidTrace modules have been used in the automation concept which advantageously does not need HPLC-techniques [353]. 

As a recently developed technology, a novel automation concept has been presented which is based on a mover, a stacking device, and a reader or washer (Twister, Zymark). In comparison to the above mentioned systems, assays based on the Twister concept are only semi-automated. The outstanding benefit is the simplification of feeding, handling, set-up, as well as the small laboratory space... 

However, automation systems that can handle the product and process diversity specially required by research laboratories on the basis of sample-oriented automation concepts (Fig. 19.1) - and with high productivity to boot - have recently begun to appear on the market. Equipment pertaining to laboratory automation may therefore, from the perspective of organization, break down into three kinds of systems decentralized, function-oriented, and sample-oriented. 

Figure 19.1. Classical function-oriented automation concept compared with central-automated sample-oriented systems.

The classical function-oriented automation concept forfeits efficiency the instant a diversity of process and products are targeted. On the other hand, by centralizing automation, i.e., by devolving automation tasks away from the periphery to a powerful central robot, highly variable processes can be tackled, e.g., in combinatorial synthesis. One feature of these so-called sample-oriented systems is that the pipetting function is centralized. 

Figure 19.5. In the course of developing the robotic platform ARCoSyn for fully automated synthesis and purification of compound arrays, a sample-oriented concept has been realized that subordinates sample functionality, thus avoiding complex transport processes between spatially separated individual functionalities. The central component is an industrial robot, which - in respect of flexibility (the gripper changing system for several centralized functions), work space (optimal utilization of available surface area, no need for a translation axis), precision, and loading capacity (option of using modules for both miniaturization and upscaling) - is adapted to the requirements of the laboratory automation concept.

For similar-sized samples, e.g. fused beads, pressed powder pellets, or metal disks, there are innovative concepts to handle samples without sample holders. Instead of a sample holder catcher, the sample magazine uses a low-vacuum suction device to ensure direct, safe transport and loading, requiring only two sample holders for the internal sample handling (Fig. 6). For laboratory automation concepts, e.g. in the cement industry, the spectrometers can be equipped with a process automation sample magazine to handle samples in steel rings without sample holders and a turning device to take process samples from a conveyor or a robot. 

For successful implementation of micro- and millireactor systems for production processes, the proof of economic benefits is cmdal. Methods of life cycle assessment are currently under development and have been described for selected processes in the literature [22,23]. Of particular importance in the cost assessment are the labor costs that lead to requirements of successful implementation of microreactor technology also in terms of computerized operation enabled by advances in process control and automation concepts [24,25]. 

So far I have stressed the automation concepts in modern plant design because I believe that they have contributed greatly to product reliability. Such automation applies to almost all process systems. 

The real power of PAIRs will become apparent when such systems move away from the islands of automation concept and Interface with other manufacturing automation software. This paper explores some possible Interfaces. 

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