Technical plant system techniques

One of the principal tasks facing the manager responsible for implementing a new plant layout is the planning and scheduling of the many activities involved in the project. Modem computerized systems have evolved into easy-to-use tools that avoid the need for a detailed technical knowledge of planning techniques. 

Two main principles of temperature measurement use thermocouples and the so-called resistance thermometer. In chemical plants both methods were applied because they are easy to fit and to maintain.The accuracy of the measurement is influenced by, for example, radiation, which must be taken into account. Thermocouples can be inserted into the pressure system using special sealing techniques, or they may be mounted within a protective tube which is introduced into the pressurized volume. Thermocouple-wires are usually protected with an isulating input in closed-end capillaries with outer diameters of at least 0.5 mm. Thermocouples are technically well tested for pressures up to 6 kbar and temperatures to approx. 800°C. Above these ranges the exact measurement is negatively influenced by several parameters, and the deviations must be taken into account. The accuracy of the temperature measurement devices is normally better than 1 °C. 

Fluoride can also be removed from a centralized water treatment point. This is common in developed or countries in economic transition and provides a longterm solution to fluoride problem in drinking water. A full-scale water purification plant based on AA-adsorption media was reported to be in operation in Kansas, USA. In this technique, all water to the distribution system is treated irrespective of its intended use. Thus, it is unrealistic way of defluoridating water since the main concern is usually fluoride ions contained in drinking water. From the technical point of view, however, centralized water treatment guarantees the quality of drinking water since the performance of the defluoridation plant can easily be monitored. Wider application of this technique for the sole purpose of removing fluoride from water is not widely reported in literature. 

There exists a whole battery of methods for the identification of hazards in the literature.4 The hazard identification techniques suitable for various stages of a project are shown in Table 3.1. Among the techniques noted in Table 3.1 the most important method is safety audits, which cover the management system and specific technical features at site level and the management system at plant level. 

Thermal. Combustion techniques bum waste for the recovery of heat energy, Waterwall combustors are the most technically developed energy recovery systems and employ special grates to bum "as received urban waste and recover steam either at saturated or superheated conditions. Over 250 plants are operating worldwide seven of them in the United States. Three of the seven were originally built as incinerators. Worldwide there have been a number of technical problems, with the control of corrosion and erosion being the most serious. The most recent European designs have solved these problems but at an increased capital cost. 

Lurgi cannot design such a system obviously they have, the plants so designed do work. Either Lurgi uses proprietary data, or they design from past experience in either case, their techniques are not available to the technical public. Nor is it known how much safety is built into their designs. 

Already our microprocessor systems have built-in checks for fault finding and soon even the diagnostic techniques will allow transmission of information from the plant to a distant technical centre. Security of performance will certainly be a key objective in all design thinking, and hopefully ensure that our food processes are designed and operated to give the highest performance standards possible. 

Very formidable technical obstacles face attempts to identify the primary actions of hormones in both plant and animal cells. These are in part due to the limited resolving power of existing biochemical techniques but also due to the special problems associated with obtaining satisfactory experimental systems. Diffusion patterns establishing complex concentration gradients of hormones are probably built up in developing plant tissues— these may be destroyed... 

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