The Equipment

The step with the longest time limits the cycle time. Alternatively, if more than one step is carried out in the same equipment, the cycle time is limited by the longest series of steps in the same equipment. The batch cycle time must be at least as long as the longest step. The rest of the equipment other than the limiting step is then idle for some fraction of the batch cycle. 

Example 4.5 Given that a low rate of production is required, convert the continuous process from Example 4.4 into a batch process. Preliminary sizing of the equipment indicates that the duration of the processing steps are given in Table 4.7. ... 

Clearly, the time chart shown in Fig. 4.14 indicates that individual items of equipment have a poor utilization i.e., they are in use for only a small fraction of the batch cycle time. To improve the equipment utilization, overlap batches as shown in the time-event chart in Fig. 4.15. Here, more than one batch, at difierent processing stages, resides in the process at any given time. Clearly, it is not possible to recycle directly from the separators to the reactor, since the reactor is fed at a time different from that at which the separation is carried out. A storage tank is needed to hold the recycle material. This material is then used to provide part of the feed for the next batch. The final flowsheet for batch operation is shown in Fig. 4.16. Equipment utilization might be improved further by various methods which are considered in Chap. 8 when economic tradeoffs are discussed. 

It was also noted in Sec. 4.4 that the hatch nature of a process can lead to less than full utilization of the equipment. Let us consider how utilization of equipment can be improved. 

Example 9.1 A process involves the use of benzene as a liquid under pressure. The temperature can be varied over a range. Compare the fire and explosion hazards of operating with a liquid process inventory of 1000 kmol at 100 and 150°C based on the theoretical combustion energy resulting from catastrophic failure of the equipment. The normal boiling point of benzene is 80°C, the latent heat of vaporization is 31,000 kJ kmol the specific heat capacity is 150 kJkmoh °C , and the heat of combustion is 3.2 x 10 kJkmok. ... 

It should be emphasized that capital cost estimates using installation factors are at best crude and at worst highly misleading. When preparing such an estimate, the designer spends most of the time on the equipment costs, which represent typically 20 to 40 percent of the total installed cost. The bulk costs (civil engineering, labor, etc.) are factored costs which lack definition. At best, this type of estimate can be expected to be accurate to 30 percent. 

For paraffinic materials, the results are close to those of a TBP, the equipment being calibrated using n-paraffins. For aromatics, the differences are larger. 

Though the type of processing required is largely dependent upon fluid composition at the wellhead, the equipment employed is significantly influenced by location whether for example the facilities are based on land or offshore, in tropical or arctic environments. Sometimes conditions are such that a process which is difficult or expensive to perform offshore can be exported to the coast and handled much more easily on land. 

The most common contaminants in produced gas are carbon dioxide (COj) and hydrogen sulphide (HjS). Both can combine with free water to cause corrosion and H2S is extremely toxic even in very small amounts (less than 0.01% volume can be fatal if inhaled). Because of the equipment required, extraction is performed onshore whenever possible, and providing gas is dehydrated, most pipeline corrosion problems can be avoided. However, if third party pipelines are used it may be necessary to perform some extraction on site prior to evacuation to meet pipeline owner specifications. Extraction of CO2 and H2S is normally performed by absorption in contact towers like those used for dehydration, though other solvents are used instead of glycol. 

The hardware items with which the processes described in Section 10.1 are achieved are called facilities, and are designed by the facilities engineer. The previous section described the equipment items used for the main processes such as separation, drying, fractionation, compression. This section will describe some of the facilities required for the systems which support production from the reservoir, such as gas injection, gas lift, and water injection, and also the transportation facilities used for both offshore and land operations. 

The production operations and maintenance group will develop a set of operating and maintenance objectives for the project. This will be a guideline when specifying the mode of operation and maintenance of the equipment items and systems, and will incorporate elements of... 

In conjunction with the production operations input into the FDP describing how the process will be operated, maintenance engineering will outline how the equipment will be maintained. Maintenance is required to ensure that equipment is capable of safely performing the tasks for which it was designed. This is often stated as maintaining the technical integrity of the equipment. 

Increasingly, maintenance engineers think in terms of the performance and maintenance of equipment over the whole life of the field. This is often at the centre of the decision on capex-opex trade-offs for example spending higher capex on a more reliable piece of equipment in anticipation of less maintenance costs later in the life of the equipment. 

Early failures may occur almost immediately, and the failure rate is determined by manufacturing faults or poor repairs. Random failures are due to mechanical or human failure, while wear failure occurs mainly due to mechanical faults as the equipment becomes old. One of the techniques used by maintenance engineers is to record the mean time to failure (MTF) of equipment items to find out in which period a piece of equipment is likely to fail. This provides some of the information required to determine an appropriate maintenance strategy tor each equipment item. 

For some cheap, easily replaceable equipment, it may be more economic to do no maintenance at all, and in this case the item may be replaced on failure or at planned intervals. If the equipment is more highly critical, availability of spares and rapid replacement must be possible. 

Breakdown maintenance is suitable for equipment whose failure does not threaten production, safety or the environment, and where the cost of preventing failure would be greater than the consequence of failure. In this case, the equipment would be repaired either on location or in a workshop. Even with this policy, it is assumed that the recommended lubrication and minor servicing is performed, just as with a motor car. 

If the performance of the equipment is monitored on a continuous basis, then abnormal behaviour can be identified, and preventive maintenance can be performed as and when required this is called on-condition preventive maintenance. The condition of equipment may be established by inspection, that is taking it off-line, opening it up and looking for signs of wear, corrosion etc. This obviously takes the equipment out of service, and may be costly. 

One of the most cost effective forms of maintenance is to train the operators to visually Inspect the equipment on a daily basis. Careful selection of staff, appropriate training and incentives will help to improve what is often called first-line maintenance. 

Enhancements to the process may be required due to sub-optimal initial design of the equipment, or to implement new technology, or because an idea for improving the production system has emerged. De-bottlenecking would be an example of an... 

FAGCI has the equipment for mass production of computer-synthesized holograms The technology of computer-synthesized holograms is widely used in Russia for protection of precious, authentic, and important documents, such as passports, securities, licenses, certificates, identification cards, etc. 

An experimental activity on the stress measurement of a pressure vessel using the SPATE technique was carried out. It was demontrated that this approach allows to define the distribution of stress level on the vessel surface with a quite good accuracy. The most significant advantage in using this technique rather than others is to provide a true fine map of stresses in a short time even if a preliminary meticolous calibration of the equipment has to be performed. 

In case of mixed systems the procedure must be varied and it would be restricted to the special film systems of interest, of course. Mixed systems would be used by inspection companies and industrial users who normally do not dispose of the equipment for measurements as mentioned above. In these cases instead of a round robin test only periodical measurements of the properties of these mixed film systems by an independent third party institution can be used for film classification and continuous surveillance. 

At the beginning of the supervision of films systems first of all the influences of the exposure-and processing installations of the project partners on the determination of the film system parameters shall be found out and subsequently the equipments for measurement shjdl be compared one with another. This round robin test comprises in detail ... 

Of course modem MPI and LPI equipments have all necessary control devices needed to ensure operation at nser defined conditions, but if these conditions have to be controlled by the inspector itsself besides the normal inspection work the human being is still a factor of operating the equipment. 

The QAP enables the user to have a consistent documentation of the variable parameters and inspection results (with camera system). A protocol can be printed out to be used as documentation for the equipment and inspection. 

Any quality or performance deviations of the equipment are printed out, the system allows fully automated operator free inspection and quality assurance documentation. 

In many industries a non-contact testing of vibrating parts of the various equipment is needed. To prevent the destruction of large aggregates rotating and moving in various directions with the large speed, the parameters of vibrations should be measured very carefully. Besides, vibrations reduce considerably the equipment s duration of life. 

Manufacturer verification" describes the measurement method of flaw charaeteristics. These characteristies are reported on the data sheet delivered with the equipment. Measurements are performed on a representative sample of flaw deteetors produeed. 

Small size, ruggedness, simple cabling and the ability to operate the equipment under adverse conditions in the field has also been design goals. The system should also conform with the regulations necessary for the CE-marking (i. e. standards and directives for EMC, Electrical Safety and Machine Safety). 

The questions connected with exception of the subjective factor of process of an estimation of its results are considered by use of the automated monitoring systems. The principles of construction of the automated systems are shown on the basis of the unified imits, and also on a principle of self-training. The examples of the equipment, realized to the present time, are given. 

Several manufacturers of transducers and equipment were contacted to give their best solution of the problems. Two instruments and five types of transducers were selected for further experiments. The equipments were very different concerning the possibility for controlling the measuring conditions and the transducer frequencies where from 10 MHz to 25 MHz with different crystal diameters and focussing lenses. 

The detrimental effect on environment is minimized and the equipments and facilities used are adequate for optimum utilization in all stages. 

The examination is made on an object (i.e. the volume of the component on which NDI information is required), using a procedure and a data organisation (i.e. the definition of the structure of acquisition data). The procedure defines the equipment. The acquisition data is produced by the equipment and arranged according to the data organisation related to the equipment. 

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