Production from

Another way to keep the concentration of PRODUCT low is to remove the product as the reaction progresses, e.g., by intermediate separation followed by further reaction. For example, in a reaction system such as Eq. (2.18), intermediate separation of the PRODUCT followed by further reaction maintains a low concentration of PRODUCT as the reaction progresses. Such intermediate separation is most appropriate when separation of the product from the reactants is straightforward. 

Figure 3.8a shows the temperature-composition diagram for a minimum-boiling azeotrope that is sensitive to changes in pressure. This azeotrope can be separated using two columns operating at different pressures, as shown in Fig. 3.86. Feed with mole fraction of A Ufa)) of, say, 0.3 is fed to the high-pressure column. The bottom product from this high-pressure column is relatively pure B, whereas the overhead is an azeotrope with jcda = 0-8, jcdb = 0.2. This azeotrope is fed to the low-pressure column, which produces relatively pure A in the bottom and in the overhead an azeotrope with jcda = 0.6, jcdb = 0.4. This azeotrope is added to the feed of the high-pressure column.

Allow the use of standardized multipurpose equipment for the production of a variety of products from the same plant. 

Figure 5.10 Distillation columns with three products. (From Smith and Linnhoff, TVans. IChemE, ChERD, 66 195. 1988 reproduced hy permission of the Institution of Chemical Engineers.)...

Separation of families by merely increasing the resolution evidently can not be used when the two chemical families have the same molecular formula. This is particularly true for naphthenes and olefins of the formula, C H2 , which also happen to have very similar fragmentation patterns. Resolution of these two molecular types is one of the problems not yet solved by mass spectrometry, despite the efforts of numerous laboratories motivated by the refiner s major interest in being able to make the distinction. Olefins are in fact abundantly present in the products from conversion processes. 

Liquid products from coking are very unstable (high diene contents), very olefinic, and highly contaminated by sulfur and nitrogen. The production of gas is considerable. 

Feedstocks for this very flexible process are usually vacuum distillates, deasphalted oils, residues (hydrotreated or not), as well as by-products from other processes such as extracts, paraffinic slack waxes, distillates from visbreaking and coking, residues from hydrocracking, converted in mixtures with the main feedstock. 

The feedstocks in question are primary distillation streams and some conversion products from catalytic cracking, coking, visbreaking, and residue conversion units. 

Fractions treated by this process are light products from the primary distillation LPG to Kerosene, or light products from thermal and catalytic cracking (visbreaking, coking, FCC). 

Once the field development plan (FDP) is approved, there follows a seguence of activities prior to the first production from the field ... 

Shallow water carbonate (reefs carbonate muds) Reservoir quality governed by diagenetic processes and structural history (fracturing). Prolific production from karstified carbonates. High and early water production possible. Dual porosity systems in fractured carbonates. Dolomites may produce H S. 

The dissolution of carbonates can create spectacular features like those found in many caves. The process is termed karstification. Some reservoirs are related to Karst. Examples are the Bohai Bay Field in China or the Nang Nuan oil field in the Gulf of Thailand. These reservoirs are characterised by high initial production from the large open pore system. However, since the Karst features are connected downdip to the waterleg this is usually followed by rapid and substantial water breakthrough. ... 

Natural water drive occurs when the underlying aquifer is both large (typically greater than ten times the oil volume) and the water is able to flow Into the oil column, i.e. it has a communication path and sufficient permeability. If these conditions are satisfied, then once production from the oil column creates a pressure drop the aquifer responds by expanding, and water moves into the oil column to replace the voidage created by production. Since the water compressibility is low, the volume of water must be large to make this process effective, hence the need for the large connected aquifer. 

The wells provide the conduit for production from the reservoir to the surface, and are therefore the key link between the reservoir and surface facilities. The type and number of wells required for development will dictate the drilling facilities needed, and the operating pressures of the wells will influence the design of the production facilities. The application of horizontal or multi-lateral wells may where appropriate greatly reduce the number of wells required, which in time will have an impact on the cost of development. 

Well completions are usually tailored to individual wells, and many variations exist. The following diagrams show a completion with a gravel pack, designed to exclude sand production downhole, and a dual completion, designed to allow controlled production from two separate reservoirs. 

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 first function of a wellsite is to accommodate drilling operations. However, a wellsite must be designed to allow access for future operations and maintenance activity, and in many cases provide containment in the event of accidental emission. Production from a single wellhead or wellhead cluster is routed by pipeline to a gathering station, often without any treatment. In such a case the pipeline effectively becomes an extension of the production tubing. If a well is producing naturally or with assistance from a down... 

These single satellites are commonly used to develop small reservoirs near to a large field. They are also used to provide additional production from, or peripheral water injection support to, a field which could not adequately be covered by drilling extended reach wells from the platform. 

An example of an application of CAO is its use in optimising the distribution of gas in a gas lift system (Fig. 11.3). Each well will have a particular optimum gas-liquid ratio (GLR), which would maximise the oil production from that well. A CAO system may be used to determine the optimum distribution of a fixed amount of compressed gas between the gas lifted wells, with the objective of maximising the overall oil production from the field. Measurement of the production rate of each well and its producing GOR (using the test separator) provides a CAO system with the information to calculate the optimum gas lift gas required by each well, and then distributes the available gas lift gas (a limited resource) between the producing wells. 

A test separator is provided on each drilling platform and Is used to test the wells sequentially. The capacity of the test separator would have to be equal to the production from the highest rate well. 

These results would be interpreted as showing that water breakthrough has occurred earlier in layer B than in the other layers, which may give reason to shut off this layer (as discussed below). The lack of production from layer C may indicate ineffective perforation, in which case the interval may be re-perforated. The lack of production may be because layer C has a very low permeability, in which case little recovery would be expected from this layer. 

Sand production from loosely consolidated formations may lead to erosion of tubulars and valves and sand-fill in of both the sump of the A/ell and surface separators. In addition, sand may bridge off in the tubing, severely restricting flow. The presence of sand production may be monitored by in-line detectors. If the quantities of sand produced become unacceptable then downhole sand exclusion should be considered (Section 9.7). 

If water or gas breakthrough occurs (in an oil well) from a high permeability layer it can dominate production from other intervals. Problems such as this can sometimes be prevented by initially installing a selective completion string, but in single string... 

Handling production from, and providing support to, a satellite field from an older facility is at first glance an attractive alternative to a separate new development. However, whilst savings may be made in capital investment, the operating cost of large processing facilities may be too much to be carried by production from a smaller field. 

The systems of such type have been developed of all last 10 years. We shall bring some characteristics of one of the last development within the framework of European BRITE project, carried out in LETT This 3D cone-beam tomograph is referred to as EVA Bench or Equipment for Voludensimetry Analysis. It is oriented on NDT of industrial products from ceramics and other composites. One of the main task of this tomograph is achievement of high resolution at study of whole internal volume of researched object. For test sample of the size 10mm spatial resolution in 50mm was obtained [14]. 

Where a Member State ascertains tliat a product, bearing the CE-marking and used in accordance with its intended use, is liable to endanger the safety of persons or health, it shall take all appropriate measures to withdraw such a product from the market. That Member State shall immediately Inform the Commission which is obliged to investigate whether or not the measure is justified. Where the Commission considers that the measure is justified, it shall immediately inform the Member State which took the initiative and also the other Member States. This entails that the other Member States must also take action against the product concerned. That latter disposition is referred to as the safeguard clause. 

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