Corrective measures design

Establishment of corrective measures designed to correct any out of control situation at each and every CCP. 

To determine the deterioration in component performance and efficiency, the values must be corrected to a reference plane. These corrected measurements will be referenced to different reference planes depending upon the point, which is being investigated. Corrected values can further be adjusted to a transposed design value to properly evaluate the deterioration of any given component. Transposed data points are very dependent on the characteristics of the components performance curves. To determine the characteristics of these curves, raw data points must be corrected and then plotted against representative nondimensional parameters. It is for this reason that we must evaluate the turbine train while its characteristics have not been altered due to component deterioration. If component data were available from the manufacturer, the task would be greatly reduced. 

Investigate the effect of the pressure surge on adjacent equipment per the 1997 edition of API RP-521. The design pressure of adjacent equipment and piping may be exceeded during a tube rupture. This is of special concern in cooling water networks. Dynamic simulation can assess the impact of a tube rupture on adjacent equipment and identify corrective measures. 

Corrective Measures Implementation (CMI) -those activities associated with the design and construction of the technology options selected and with performance monitoring. 

Once the candidate corrective measure alternatives have been identified, a more detailed evaluation of each alternative needs to be undertaken. From an engineering perspective, the first step in the evaluation process would include the development of a conceptual design for each alternative. The conceptual design would consist of a process description, a process flow diagram and a layout drawing. Preliminary sizing of equipment and utility and land requirements would be developed. In addition, chemical requirements and residuals produced can be estimated. From the conceptual design, permitability and residuals disposal issues can be identified and addressed. 

After the conceptual designs for each candidate corrective measure alternative have been developed, each can be compared using the following evaluation criteria ... 

Design temperatures must be specified at a margin above normal operating temperature sufficient to permit the detection of abnormal temperatures and institution of corrective measures by manual or automatic controls. 

As part of the verification plan, you should include an activity plan that lists all the planned activities in the sequence they are to be conducted and use this plan to record completion and conformance progressively. The activity plan should make provision for planned and actual dates for each activity and for recording comments such as recovery plans when the program does not proceed exactly as planned. It is also good practice to conduct test reviews before and after each series of tests so that corrective measures can be taken before continuing with abortive tests (see also under Design validation). ... 

Due to the capacity of deep wells to store injected waste for a long period of time, if the correct measures are taken in design, construction and operation, deep well injection can provide an effective and environmentally safe method of concentrate management. The major environmental concern for deep well injection is the potential for contamination of nearby aquifers, which may be used as a source of drinking water. Six pathways have been defined that describe the potential migration of concentrate that can cause contamination of aquifers (Shammas et al. 2009 United States Environmental Protection Agency 2002) ... 

Table VII illustrates the entry format for the carboxamide fragment. Measurements from a number of solutes have established the values for many of its bond environments and its susceptibility to proximity effects. Table VIII shows the fragment data for N-oxy-urea. It is immaterial which direction the operator chooses to enter the fragment structure, because the program develops a unique sequence for fragments just as it does when dealing with complete structures. Of course the operator must use care to associate the correct bonding designations with the appropriate data. Two calculations using this fragment will serve to illustrate some features of the program.

All equipment designed to measure surface area, adsorption-desorption isotherms or pore volume by adsorption actually determines the quantity of gas condensed on a solid surface at some equilibrium vapor pressure. The surface area or pore volumes and pore sizes are then calculated by means of an appropriate theory used to treat the adsorption and/or desorption data. Depending on the apparatus employed, the adsorbed quantity is measured as volume or weight. The accuracy of an adsorption apparatus is, therefore, dependent upon its ability to correctly measure either of these quantities. 

Limits are conservative measures designed to signal potential or actual drift from historical or design performance characteristics. They are not extensions of product specifications, but are intended to flag changes so that corrective action may be taken before product quality is adversely affected. Not all situations require use of both alert and action limits. 

An important property of design of experiments is a search for increased accuracy in fixing a factor and measuring an error. The researcher must be able to determine and estimate a measurement error correctly. Measurements and measurement errors are a subject of special study, see [7, 8]. 

An engineering evaluation should then be made of the worst case consequences with the goal that the plant will be safe even if the worst case occurs. When the process designers know what the worst case conditions are, they should try to avoid worst case conditions, be sure adequate redundancy of safety systems exists, and identify and implement lines of defense. These lines of defense could be preventive measures, corrective measures or sometimes as a last resort, containment or possibly abandonment of the process if the hazard is unacceptable. It is important to note that the worst case should be something that is realistic, not something that is conceivable but extremely unlikely. 

For gases and liquids the liter is a much more practical measure of volume, especially in concentration expressions, than the derived unit of cubic meter, m3. Usage therefore has established the liter (L) as an accepted named unit, even though cubic decimeter (dm3) is the correct SI designation. The only prefix to be used with liter is milli, that is milliliter (ml). The symbol L is used for liter to prevent confusion with the letter I and the number 1. 

As can be noted from tlie analysis of the ethylene plant, one of the major disadvantages of the FTA is lack of recommendations for preventative and corrective measures. FTA, however, has the advantage of pinpointing tlie sequence of events tliat could lead to an midesired TOP event. Once tliese causes liave been identified, an experienced design team can recommend solutions in tlic form of design alternatives and/or instrumentation. In recommending solutions, tlie probability, severity, and economics of each case must be taken into account. For example, tlie problem of temperature control... 

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