Operating procedures modifications

Change in the PSM rule includes all modifications to equipment, procedures, raw materials, and processing conditions other than replacement in kind. These changes are managed by identification and review prior to implementation. For example, any operation outside of the operating procedures parameters requires review and approval by a written management of change. 

Once the Clobberers that lead to violations of quantitative constraints have been identified, we must search for modifications of the operating procedure, which will negate the effects of the Clobberers on the procedure and thus restore its feasibility. There exist two general mechanisms for achieving this objective, and in the following paragraphs we will discuss each one of them. 

Design modifications for the accommodation of feasible operating procedures. Section V introduced some early ideas on how the ideas of planning operating procedures could be used to identify modifications to a process flowsheet, which are necessary to render feasible operating procedures. More work is needed in this direction. Clearly, any advances in dynamic simulation with discrete-time events would have beneficial effects on this problem. 

Members of the update team should review a copy of the initial PrHA and check completion of action items. The team should thoroughly review current PSI and descriptions of all process modifications made since the initial PrHA report was finalized. A thorough review of the PSI is necessary to make sure that the PrHA incorporates any new hazardous materials, process technologies, equipment, and/or operating procedures. Finally, the team should review all findings and resolutions from the initial PrHA to assure that they have been adequately addressed. 

An effective management system to ensure process integrity is essential and must include up-to-date operating procedures, product changeover instructions, and checklists that cover instrumentation, equipment arrangement, and procedures procedures must also include adequate checks and reviews to ensure the required changeover modifications have, in fact, been made when required. 

The waste audit should systematically evaluate opportunities for improved operating procedures, process modifications, process redesign, and recycling. 

The team s recommendations (immediate and long term) as to steps that might be taken to prevent any recurrence of incidents of a similar nature. These recommendations should not be confined to such matters as plant modification, but should, if appropriate, embrace training (retraining), assessment of operational procedures, and strengthening of safety measures. Recommendations that improve work systems and conditions make it harder for people to make mistakes. The team should also indicate what... 

Obviously, considerable overlap exists between these arbitrary divisions, for example, a piece of work setting out to synthesise new compounds can also shed light on the mechanism [70], and similarly, a study designed to investigate the mechanism can result in modifications to operational procedures [71]. 

Among the most effective of the modifications to Claus operating procedure is accurate temperature control of the catalyst beds. Gamson and Elkins (27) in the early 1950 s showed that equilibrium sulfur conversion efficiencies in the catalytic redox reaction rise dramatically as operating temperatures are lowered toward the dewpoint of sulfur. While some highly efficient subdewpoint Claus type processes are now in use the bulk of sulfur production from H2S still requires that the converters be operated above the dewpoint. Careful control of converter bed temperature has, however, contributed to improved efficiencies. This has in large part resulted from better instrumentation of the Claus train and effective information feed back systems. 

The water analyses were carried out using an automatic Karl Fischer titrator (Aquatest II) and normally no problems were encountered. However, for the benzene-water-hydrochloric acid system, the acid strongly interfered with the water analyses. With a slight modification of operating procedure, reasonably satisfactory, but low precision, results were obtained For these analyses, the sample was introduced into the analyzer by injection with the syringe needle below the surface of the vessel solution and every benzene injection was preceded by a 100 yl methanol sample. 

For the GC/MS analysis of unknown chemicals, more or less universal procedures have to be used, because of the large variety in matrices and scheduled compounds. This requires the use of ROPs rather than of standard operating procedures (SOPs), because ROPs allow modification of procedures in the process of analysis (validation on the job). However, SOPs have to be followed for instrument calibration and validation. 

In any case, a strict standard operating procedure (SOP) must be followed to assure at least reproducibility. Figure 27 shows a useful SOP which might require some modifications depending on the characteristic properties of cell suspensions. Wet weight determinations are by far less accurate since a defined water content is not easy to arrange reproducibly. 

Operational Procedures operator commands, override control, process monitoring, parameter modification, load scheduling, startup and shutdown, fault-finding instructions, user manuals and documentation... 

The Microsimulation test (MST). Modification of the operating procedure and experimental conditions of a convential micro activity test (MAT) has led to the so-called microsimulation test (MST, see Figure 3). Basically, the reactor is a fixed bed with transient operation during the catalyst contact time. A complete description of the operation and design of the MST reactor is given by O Connor in (11). Table I gives an overview of the main differences between the MR and the MST. 

In the pipette method (Figure 7.7), concentration changes occurring within a settling suspension are followed by drawing off definite volumes, at predetermined times and known depths, by means of a pipette. The method was first described in 1922 by Robinson [14] who used a normal laboratory pipette. Various modifications were later suggested which complicated either the operating procedure or the apparatus [15]. Andreasen was the... 

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