THE FIELD LIFE CYCLE

Introduction and Commercial Application This section provides an overview of the activities carried out at the various stages of field development. Each activity is driven by a business need related to that particular phase. The later sections of this manual will focus in some more detail on individual elements of the field life cycle. 

Introduction and commercial application Safety and the environment have become important elements of all parts of the field life cycle, and involve all of the technical and support functions in an oil company. The Piper Alpha disaster in the North Sea in 1988 has resulted in a major change in the approach to management of safety of world-wide oil and gas exploration and production activities. Companies recognise that good safety and environmental management make economic sense and are essential to guaranteeing long term presence in the industry. 

Volumetric estimates are required at all stages of the field life cycle. In many instances a first estimate of how big an accumulation could be is requested. If only a back of the envelope estimate is needed or if the data available is very sparse a quick look estimation can be made using field wide averages. 

This section will consider the role of appraisal in the field life cycle, the main sources uncertainty in the description of the reservoir, and the appraisal techniques used to reduce this uncertainty. The value of the appraisal activity will be compared with its cost to determine whether such activity is justified. 

Appraisal activity, if performed, is the step in the field life cycle between the discovery of a hydrocarbon accumulation and its development. The role of appraisal is to provide cost-effective information with which the subsequent decision can be made. Cost effective means that the value of the decision with the appraisal information is greater than the value of the decision without the information. If the appraisal activity does not add more value than its cost, then it is not worth doing. This can be represented by a simple flow diagram, in which the cost of appraisal is A, the profit (net present value) of the development with the appraisal information is (D2-A), and the profit of the development without the appraisal information is D1. 

At each stage of a field life cycle raw data has to be converted into information, but for the information to have value it must influence decision making and profitability. 

As introduced in Section 14.2, bottlenecks in the process facilities can occur at many stages in a producing field life cycle. A process facility bottleneck is caused when any piece of equipment becomes overloaded and restricts throughput. In the early years of a development, production will often be restricted by the capacity of the processing facility to treat hydrocarbons. If the reservoir is performing better than expected it may pay to increase plant capacity. If, however, it is just a temporary production peak such a modification may not be worthwhile. 

There is potential in the anti-HIV field. Polyoxometallates of the Keggin type bind to viral envelope sites on cell surfaces and interfere with virus adsorption. Metal-chelating macrocyclic bicyclam ligands are among the most potent inhibitors of HIV ever described, and there is considerable interest in the role of Zn proteins in the viral life cycle. 

The relatively new field of industrial ecology provides a useful organizing framework for DEE (Lowe, 1993). Design for Environment (DEE) is the terminology for the third component of the LCA life-cycle improvement assessment. The principle of sustainable development suggests that companies or individuals should try both to minimize the consumption of virgin natural resources and to minimize the generation of waste material that has no productive use. 

Satisfactory completion, review, and reporting of each qualification, including those associated with field instrumentation and regulating devices, will release the computer system for the subsequent life-cycle phase. 

To observe such rf oscillations, we have used two very different techniques, each needing only relatively simple apparatus. The first technique is called micro-DEP and essentially requires only a microscope. > Here one observes the collection of various highly polarizable particles by a cell so as to examine the radio frequency (if) field emitted from it. In the second technique, direct observation is made of the spinning of cells evoked by external rf fields. Both methods yields similar conclusions as to the nature, frequency, strength, and occurrence of the rf electrical oscillations of cells. We believe, therefore, that the presence of the postulated rf oscillations has been established beyond reasonable doubt. It now remains to study their meaning. Are they cause or effect, necessity or frill, in the life of cells Where and how do they operate What causes them What controls, intracellular or intercellular, do they evoke or reflect With what processes are they associated in the cellular life cycle ... 

Based on the statistical prognosis and the specifications of possible damage during the product life cycle in the early phase of product construction, it is feasible to conclude actions to optimise the product and its subcomponents. The actors OEM and supplier of the value added network benefit primarily from this information, because they can optimise their products and subcomponents. Furthermore, it is possible to reduce technical failure analysis costs through drawing selected samples of damaged components out of the field. 

The traditional life cycle for coatings in most applications begins with the surface-modification process in a manufacturing environment. During use in the field, the coating suffers degradation due to processes such as wear and corrosion, until it reaches the end of its service life. 

Another important issue is that because sensors and final elements are further exposed (in the field) to physical and chemical loading and parameter variations, as already discussed in the previous chapter, failure rates are high for sensors and final elements. Hence a larger share, as shown in the pie chart in Fig. VIII/l-O-lB, is accountable for failure of sensors and final elements. The relationship between SIL and the safety life cycle will be focused on in the following clauses. 

The life cycle inventory is a quantification of relevant energy and material inputs and environmental release data associated with the production of cotton fixrm cradle-to-gate (fiber) and manufacturing from gate-to-gate (fabric). The associated life cycle assessment models the environmental impact of representative cotton apparel from the field through to consumer care, use and disposal. 

The acceleration transforms that can be used to estimate the field life of tin-lead and lead-free solder joints based on the results of temperature cycling tests... 

If, however, the calculated remaining life of a component (RL J as defined in Eq. (12.4) is greater than the field life (FL), can be assumed to be zero. This is based on the assumption that the KPI is a performance indicator reflecting the effect on operating costs (Opex) and does not consider depreciation against the initial capital cost (Capex). The number of replacement cycles (N ) can be estimated with Eq. (12.3) ... 

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