Chemical production processes

In a chemical production process at least one of the unit operations (the chemical reactor) is the place in which chemical conversion takes place. However, the chemical upstream reactor is proceeded by a series of unit operations in which the new materials are downstream prepared (the upstream operations). After conversion has taken place, the products are operations subjected to a further series of unit operations (the downstream operations). These downstream operations include product recovery and purification steps. A typical example of a production process is illustrated in Figure 1.1. 

Within the chemical industry, micro-organisms and enzymes are often used as catalysts. It is possible for a unit operation in an essentially chemical production process to be a biochemically catalysed step giving rise to a mixed chemical/biochemical production process. The products of these reactions include organic chemicals, solvents, polymers, pharmaceuticals, and purfumes. Mixed chemical/biochemical production processes are continuously innovated and optimised, mainly for economical reasons. 

Worz et al. describe in detail why micro reactors can give advantages concerning all three tasks [110-112]. They illustrate their analysis by two application examples, concerning a liquid/liquid reaction and a catalyzed gas-phase reaction, both representing industrial chemical production processes. 

Selectivity may also come from reducing the contribution of a side reaction, e.g. the reaction of a labile moiety on a molecule which itself undergoes a reaction. Here, control over the temperature, i.e. the avoidance of hot spots, is the key to increasing selectivity. In this respect, the oxidative dehydrogenation of an undisclosed methanol derivative to the corresponding aldehyde was investigated in the framework of the development of a large-scale chemical production process. A selectivity of 96% at 55% conversion was found for the micro reactor (390 °C), which exceeds the performance of laboratory pan-like (40% 50% 550 °C) and short shell-and-tube (85% 50% 450 °C) reactors [73,110,112,153,154]. 

Stardust Chemical Co. planned a new plant for two intermediates. The chemical production processes were not yet fully worked out because of lack of data on how large the production plant would have to be. The following information is not complete and partly misleading. 

Larger parts of the waste generated in the inorganic chemicals production process are found in the wastewater emanating from the industry. However, if the wastewater generation could be... 

Nevertheless, there are several hurdles to overcome. Biotransformation has to compete with a chemical production process. The production of bio-based bulk chemicals and intermediates from white biotechnology must be economically viabile [67]. This means that the biotechnological product must be cheaper to produce or of higher quality than products based on classical chemical routes. And, incidentally, switching to a novel process takes time and money. Therefore, process solutions are required which are adapted to the special needs of biocatalyzed reactions. Within this chapter, several specific tasks have been addressed, illustrating universal possibilities to overcome the limitations found in bioprocesses. 

Pujado, P. R., m Handbook of Chemicals Production Processes, Meyers, R. A., Ed., McGraw-Hill, New York, 1986,1.16-1. 

In the previous section, a simple chemical production process has been introduced and formally described by the means of RTN extended by places. The solution of the above problem is a straightforward task and can be performed without... 

Integrated Short and Midterm Scheduling of Chemical Production Processes - A Case Study... 

Finally, an important characteristic identified in chemical production processes are time-consuming and costly setup operations. Thus, the representation of time is a critical issue in the modeling of chemical production processes. Three fundamental deficiencies of the representation result if continuous processes are modeled by standard bucket-oriented lot-sizing models. These are the carry-over of setup states... 

A production location comprises one or multiple production plants where production resources are located. Production resources are single units or groups of production units aggregated to production lines or assets. Having the structure of chemical commodity value chain network as a network of chemical production processes in mind presented in fig. 34 (Al-Sharrah et al. 2001), production locations include respective resources and transportation lanes between production locations to model relations in chemical Verbund structures. 

The incident related in sidebar 1.1 points to the purpose of this text—namely, to emphasize the importance of chemical industry production facilities (yes, sugar is a chemical, an organic chemical sugar production qualifies as a chemical production process) being ready for any contingency— any being the key word. 

Meyer, Robert A., Handbook of Chemical Production Processes, McGraw-Hill, 1986. 

The perspectives for an increasing use of biotechnology processes (biocatalysis, microbial fermentation) for LMW fine chemicals are promising. Substitution of traditional chemicals by biotechnology processes constitutes the most important means for reduction of manufacturing cost for existing fine chemicals. By 2010,30-60% of fine-chemical production processes are expected to comprise a biotechnology step ... 

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