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Energy consumption in Europe will grow, as in other parts of the world. This growth will be sustained by a combination of primary sources:
Chemistry research in the fossil fuel area is targetted on the search for new efficient heterogeneous (solid) catalysts for the production and refinement of vehicle and aircraft fuels. The chemical industry strives with increasing success to minimise the environmental impact and energy cost of the refining processes while maximising the energy content of the fuels produced. Heterogenous catalysts are also employed with increasing effectiveness in the conversion of exhaust gases from unavoidable combustion processes into relatively benign substances. Chemists and chemical engineers in the nuclear industry are engaged in the manufacture of nuclear fuels, which is primarily a chemical rather than a metallurgical process. They are also involved in spent fuel reprocessing, the separation and recovery of uranium and plutonium by solution chemistry. The miniaturisation of nuclear reactors through micro-engineering and micro-chemical techniques, particularly exploiting new materials technology, will have substantial advantages for the decommissioning and decontamination of future redundant nuclear power plants. Chemists play a key role in nuclear waste monitoring, management and control.
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Chemical engineers are people who turn chemists' ideas into products. Engineering is an independent
science with developed concepts for new process routes.
The operation and management of chemical manufacturing plants and processes have been transformed in the last 30 years by computing technology. Computer power and speed have increased so much that real-time dynamic process simulation has become possible and, in turn, advanced feed-forward control has also become practicable. The operation of chemical processes generates large amounts of information, only some of which is easily accessible at the moment. However, modern software technology, including large-scale networking (for example via the Internet), is starting to provide techniques for capturing, systematising, relating, accessing and presenting this information in a manageable form. This will have a powerful impact on the design, control and optimisation of chemical processes, in particular through greatly enhanced computer modelling techniques. Novel mathematical techniques (fuzzy logic, genetic algorithms and neural networks) make possible the development of sophisticated new modelling and process control systems. In neural networks, sensor signals are introduced and weighted in an intricate layered system, more or less as neurones are believed to work in the human brain. Such a system can be made to be self-learning, can be very fast and would not require complex hardware. However, neural networks will not be used where operational safety might be put at risk, but will be used in conjunction with orthodox feed-forward control backed up by emergency shut-down systems. The combination of process understanding, improved analysis, cheap, powerful computers and advanced software will transform our insights into operating processes with consequent economic and technical benefits. The concept of automatically self-regulating chemical plants is not far from reality.
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Traditionally, the monitoring of quality and purity control in chemical manufacturing has been
achieved by the analysis of samples removed at various points in the process cycle, interpretation of
the data obtained and feedback to the plant managers, who can then alter the plant operating
conditions. This is time-consuming and inefficient. The in situ analysis of processing conditions in
real-time, through incorporation of sensors linked to computers within a neural network, closes the
loop in plant management and control procedures and will significantly improve efficiency.
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A better understanding of processes will enable us to develop radically new approaches to the
manufacture of chemicals, for example by combining several unit operations into one or bringing
product manufacture to the point of sale.
Today's chemical plants are easily recognisable. Their architecture is based on distillation columns, reaction vessels, filters and mixers, whose operational principles were already known in the 1950s. However, recent research in chemical engineering has greatly improved understanding of the basic chemistry and physics of processing. This is stimulating the design of new types of equipment which will not only be more efficient but less obtrusive. For instance, coupling chemical reaction with separation or heat transfer has led to the concept of multi-functional reactors with increased yield. Examples are reactive distillation and reactive extraction, where advantages of the separation techniques are used for the design of the reaction process. In general, process integration leads to savings in energy consumption and raw materials. Conversely, decoupling may be beneficial. Instead of using one single tank to carry out a precipitation where the flow pattern is complex and difficult to control, a precipitator where nucleation is to be decoupled from particle growth and agglomeration could lead to significant improvements in the product's quality. Processes which involve rapid changes in the physical properties of the reactants, for example major changes in viscosity, can benefit from the design of specialised equipment. A challenging possibility which integration and intensification raises is the movement of the manufacture of certain chemicals from large centralised sites to small manufacturing units at the point of consumption. This approach does not challenge the concept of economy of scale, but rather shifts it from the amount of product manufactured to the number of plants manufacturing it. Full process design will precede plant design, and environmental protection will be an integral part of the production process. Emissions to the environment from both deliberate and accidental sources will be minimised. Processes of the future will generate few leaks and little waste. The amount of water, air and solvents used in chemical processing will be reduced to a minimum. As far as possible, production of hazardous intermediates will be suppressed and effluent recycled. The treatment of wastes will take place in the plant itself, resulting in the necessity to treat smaller amounts of effluent containing higher concentrations of contaminants. Analytics will allow products to be monitored until recycled or destroyed. Intrinsic safety will be improved by handling and storing smaller volumes of materials and using smaller reactors.
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