Runs test

Selection of Equipment If a new product is being considered, the preliminaiy study must be highly detailed. Laboratory or pilot-plant work must be done to establish the controhing factors. The problem is then to select and instaU equipment which 1 operate for quantity production at minimum overall cost. Most equipment vendors have pilot equipment available on a rental basis or can conduct test runs in their own customer-demonstration facilities. 

At the start of the leaf test run, the hose between the test leaf and filtrate receiver should be crimped by hand to bring the filtrate receiver to the operating vacuum level. The use of a valve at this point is not only less convenient but very frequently results in a hydraulic... 

For top-feed applications, the most convenient assembly is that shown in Fig. 18-95. The depth of the dam must, of course, be sufficient to contain the total quantity of feed shiny required for the test. Since the test leaf is mounted on top of the vacuum receiver, it is nec-essaiy to provide a valve between the test leaf and the receiver so that the desired operating vacuum may be obtained in the receiver before the start of a test run. It is imperative, however, that there be no restriction in this valve. The preferred choice is a ball valve with the full bore of the drainage piping. 

Generahzed correlations are available for each of the operations which make up the full filter cycle. This means that simulated operating conditions can be varied to obtain a maximum of information without requiring an excessive number of test runs. The minimum number of test runs required for a given feed will, of course, vary with the expertise of the experimenter and the number of operations performed during the filter cycle. If, for example, the operation invdves only the dewatering of a slurry which forms a cake of relatively low to moderate porosity, frequently sufficient data can be obtained in as little as six runs. For more difficult tests, more runs are usually advisable, and the novice certainly should make a larger number of runs as there is likely to be more data scatter. 

When a flocculated feed is added to a filter tank, there is a definite time lag before this material reaches the surface of the filter medium. Since this lag time is not known at the time of testing, a lag time of 8 to 10 minutes should be allowed before starting the first leaf test on a flocculated shiny. Two, or perhaps three, tests can be run before the elapsed time exceeds the probable retention time in the full-scale filter tank. With knowledge of the elapsed time after flocculation and data relating to the rate of degradation, the rates obtained on the leaf test runs can be adjusted to some constant lag time consistent with the anticipated full-sc e design. 

Continuous pilot-plant test runs are generally recommended to verify the laboratory results and to estabhsh criteria for plant design. Facihties for these runs are available at a number of minerals-processing research centers. 

The instrumental analyzer procedure, EPA Method 3A, is commonly used for the determination of oxygen and carbon dioxide concentrations in emissions from stationary sources. An integrated continuous gas sample is extracted from the test location and a portion of the sample is conveyed to one or more instrumental analyzers for determination of O9 and CO9 gas concentrations (see Fig. 25-30). The sample gas is conditioned prior to introduction to the gas analyzer by removing particulate matter and moisture. Sampling is conducted at a constant rate for the entire test run. Performance specifications and test procedures are provided in the method to ensure reliable data. 

Short-time tests also can give misleading results on alloys that form passive films, such as stainless steels. With Borderline conditions, a prolonged test may be needed to permit breakdown of the passive film and subsequently more rapid attack. Consequently, tests run for long periods are considerably more reahstic than those conducted for short durations. This statement must be quahfied by stating that corrosion should not proceed to the point at which the original specimen size or the exposed area is drastic y reduced or the metal is perforated. 

Technology transfer is a critical step in ensuring project success. The client must recognize that each toller is different in regard to how they progress from the laboratory to a test run to production. The toller selection step should have revealed that each candidate company possessed different levels of skill, experience and management culture. 

One method that can be used to enhance the efficiency of technology transfer presents itself when a client has a laboratory or pilot plant producing the materials. When this is so, the toller s personnel can visit the site, observe the processing and ask questions of the research and development team. Conversely, the research and development team or chemists and engineers from the client can witness any test runs taking place at the toller s plant. These options allow both companies to ask questions, give advice on process and... 

Employee Participation Preparation for startup is an excellent opportunity to document employee participation. If a toller is covered under the OSHA PSM regulation, they must record PHA participants, procedure writers and reviewers, PSSR team members and test run team members. All these roles reflect the true intent of this element of process safety. Eveiyone benefits from intimate involvement in the management system used to protect life and health. 

Some toll processes lend themselves to test runs in the pre-startup phase. Actual materials for the toll may be used in the test or substitute materials, typically with low hazard potential, are often used to simulate the charging, reaction, and physical changes to be accomplished in the toll. Flow control, temperature control, pressure control, mixing and transferring efficiency can be measured. Mechanical integrity can be verified in regard to pumps, seals, vessels, heat exchangers, and safety devices. 

Test run steps can frequently be incorporated into process startup procedures. Two examples would be pulling a vacuum on vessels and verifying it holds, or distilling a solvent and checking for the presence of water to verify the mechanical integrity of the heating and cooling equipment. 

When a test run is performed using the actual materials for the toll, it is a prime opportunity for the toller and the client to document the capability of the equipment, instrumentation, and process steps. During such a test, frequency of sampling may be increased, additional analyses performed and yield capabilities checked to find the optimum setpoints and timing for the toll process. Health, safety and environmental staff may choose to provide close coverage of the test run to evaluate areas for improvement during the actual startup and long term operation. 

In either type of test run, an opportunity exists to ensure the utilities for the process are capable of performing their function. 

Test runs also allow the primary steps of operating procedures to be validated and checked for logic or human factors aspects. 

Some tolled products can be reworked if they fail quality assurance tests. In these cases the production cost may go up, but the product is not a complete loss. However, other tolled products, some pharmaceuticals for example, could be completely ruined by similar processing mishaps. Losses in these cases can be quite extensive. Test runs and approved rework procedures for such products may help avoid these losses. 

There are some considerations and planning that can assist in performing a successful test run. 

Have the team set clear goals for the test run. Ensure they are measurable. 

If a design limit test is included in the test run (such as a hydrostatic test) and it exceeds safe operating limits, consider writing a special procedure for this part of the test. 

If substitute materials are used in the test run ensure they are compatible with the toll s raw materials, products, materials... 

A test run involving the actual raw materials for the toll or the initial startup that follows a water batch and PSSR is an appropriate time to evaluate any planned changes necessary for increasing production later in the toll. 

The tolling team has analyzed the hazards, addressed the risks and modifications using a management of change system, revised and written procedures, trained the workers, performed a PSSR, and completed any required test runs. The pre-startup phase is complete at this point. 

Calibration run or autoluning is a I caiurc of the motor s malhcmalical mode) that can establish the motor parHiiieiers with its test run. 

Ah regulator, relief valve, and relay settings must be doeumented by the vendor. The expander-eompressor lube system must be test-run at design differential pressure with the reservoir vented to atmosphere. 

Full documented formal test runs at design and normal conditions. All instruments need to be calibrated for the runs and the documentation should include more than just the primary process variables of temperature, pressure, flow, and composition... 

After the heat run, the compressor continues to run on air and the highest pressure practical is imposed, while the speed is set to the normal operating speed. The capacity and power should be noted as well as bearing temperature and the other instrumentation used during the test. If oil buffered seals are used and the test run is expected to exceed 250°F, the test procedure may have to be modified to avoid the possibility of an explosion hazard. 

Variable Deviation of test from value specified (plus or minus) Fluctuations from average during any test run (plus or minus)... 

The standard melt flow index machine is often used for characterising the flow properties of polypropylene and to provide a rough measure of molecular weight. Under the conditions normally employed for polyethylene (2.16 kg load at 190°C) the flow rate is too low for accurate measurement and in practice higher loads, e.g. 10 kg, and/or higher temperatures are used. It has been found that a considerable pressure drop exists in the barrel so that the flow towards the end of a test run is higher than at the beginning. 

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