Product quality specification

Product quality specification Contractual agreements Capacity and availability Concurrent operations Monitoring and control Testing metering Standardisation Flaring and venting Waste disposal Utilities systems... 

One of the primary objectives of production operations is to deliver product at the required rate and quality. Therefore the product quality specification and any agreed contract terms will drive the activities of the production operations department, and will be a starting point for determining the preferred mode of operation. The specifications, such as delivery of stabilised crude with a BS W of less than 0.5%, and a salinity of 70 g/m, ... 

The design of production plants for the manufacture of the three categories of product varies considerably. Fine chemicals are usually produced in batch reactors, which may also be used for the production of a variety of similar products. Fine chemicals usually have demanding product quality specifications and, consequently, a significant fraction of the production costs are involved in product purification and testing. Intermediate volume chemicals have less rigorous quality specifications than fine chemicals and are usually manufactured in product-specific-plants, either as batch or continuous flow processes. Bulk chemical production plants usually operate continuous flow processes... 

The total stream and individual component flows do not normally need to be shown to a high precision on the process flow-sheet at most one decimal place is all that is usually justified by the accuracy of the flow-sheet calculations, and is sufficient. The flows should, however, balance to within the precision shown. If a stream or component flow is so small that it is less than the precision used for the larger flows, it can be shown to a greater number of places, if its accuracy justifies this and the information is required. Imprecise small flows are best shown as TRACE . If the composition of a trace component is specified as a process constraint, as, say, for an effluent stream or product quality specification, it can be shown in parts per million, ppm. 

Let us consider now, however, a more realistic model. Products quality specifications are not generally given as absolute quantities, but rather in terms of maximum or minimum values. Thus the linear equations in Eq. (1) become the linear inequalities 5... 

Six-Sigma Approach Product quality specifications continue to become more stringent as a result of market demands and intense worldwide competition. Meeting quality requirements is especially difficult for products that consist of a very large number of components and for manufacturing processes that consist of hundreds of individual steps. For example, the production of a microelectronic device typically requires 100 to 300 batch processing steps. Suppose... 

One of the largest uses of petroleum coke is for anodes employed in the production of aluminum. This usage demands a somewhat premium feedstock to produce sponge coke that is low in metal and sulfur content in order to meet product quality specifications. After production in a delayed coker, anode quality coke must be calcined to remove VCM and moisture. 

This process may take several months. If initial specifications on product quality cannot be met, then changes may be made to mechanical equipment present, chemicals applied, rate of crude-oil charge, type of crude oil processed, or product quality specifications. The process of optimizing the desalting program then starts again. On particularly difficult crude oils this process may last many years, as is the case in refineries processing heavy crude oil. 

Unlike previous work in MultiVBD column, in this work, the optimal design and operation of MultiVBD column is considered under fixed product demand and strict product quality specifications. Overall product demands, product quality and feed specifications allow calculation of product profiles (amount of each product) of each batch a priori using steady state mass balance calculations. 

Control of the finished product—quality specifications including all requirements emd methods of analysis of a batch of the product. 

It is, of course, critical for testing laboratory personnel to be fuUy familiar with all the details of the tests they are performing. But it is also important for nonlaboratory personnel to know at least the significance, advantages, and limitations of particular tests used to characterize product quality. Both the suppliers and the customers need to agree on the appropriate product quality specifications, and this can be achieved by understanding the intricacies of the respective test methods. 

As mentioned above, it is an obligation of the filter user to validate the sterilization processes applied to the niter. Most often sterilizing filters will be autoclaved. The effects of a particular autoclave process on the quality and quantity of extractables obtained from filters should be evaluated using the pharmaceutical fluid that is intended to be filtered. The filtrate should be demonstrated to be particle free and biologically inert chemical extractables should not exceed the levels of contaminants allowed in the product quality specification. 

Critical control points (CCPs) are those locations within a process where control can be applied to protect product quality, specifically to prevent and eliminate quality hazards or to reduce them to acceptable levels [11]. For controlling hazards, the appropriate CCP may be positioned in the sub-sequent step from the actual hazard location. In addition, more than one CCP can be used to control a single hazard and more than one hazard can be controlled by a single CCP [11]. 

A side stream of gas is bypassed around the shift unit to achieve the correct Hj CO ratio for the methanol synthesis process. Methanol synthesis itself operates at about 80 bar using the Lurgi Low Pressure Methanol Process followed by a distillation step to achieve the required product quality specification. 

Alhajri, I., Elkamel, A., Albahri, T., and Douglas, P. A nonlinear programming model for refinery planning and optimisation with rigorous process models and product quality specifications. International Journal of Oil, Gas and Coed Technology, l(3) 283-307,... 

On the basis of the polymerization alone, it is difficult to specify definite dryer selection rules since typically polymer properties differ over a wide range. The choice of dryer is also limited by the physical properties of the polymers, e.g., polymer-handling characteristics, individual or closely related drying curves, properties of the emitted volatiles, limitations on temperature, and particle size and distribution requirements. Other factors include equipment space limitations, production rates, pollution control requirements, solvent recovery, thermal sensitivity, and product quality specifications. 

The primary written exercise is a discussion of the possible reasons that quarrying ceased at this site. These include difficulties with water management, encroachment of urban development, difficulties in meeting product quality specifications, and the more basic issue of a depleted resource. Each of these issues is teased out of the discussions at each stop around the excursion, as was described in the previous section. 

A flow-conversion model, incorporating a tanks-in-series residence time distribution and the reaction kinetics, agreed well with the experimental results, predicting that the reaction could be performed at relatively low residence times when kinetically controlled. The model led to a number of insights into the optimal operation of the OBR. The most significant prediction was that the OBR could give the desired conversion and selectivity at lower temperatures, without significant alteration to other process variables, such as residence time and molar ratio. These predictions were verified by experiment. Furthermore, at these lower temperatures an improved product quality specification could be achieved, if necessary. 

Polymerization processes have adopted a character of continuous multiproduct plants, in response to the current demand for polymers. Precisely, the variability observed in the polymer market demand, in terms of product quality specifications, calls upon frequent grade transition policies on the polymerization plants, with legitimate consequences on process economics, due to the regular necessary disturbances from steady-state operating conditions. Therefore, the issue of how to operate such process as continuous multiproduct plants, in a global polymer industry environment with intense competitive pressures, emerges nastily. 

Many other additives can be added to PP to provide or improve different functionality. Commonly used functional additives are given in Table 11 and further discussed in Section 4. However, it should be noted that the improvement in a certain property (or properties) on addition of additives is generally at the expense of some other useful properties. Hence, any change in material should be considered thoroughly to understand its full impact on the product quality, specification and suitability for the intended application. 

Accurate property measurement is key to the capture of many of the benefits of process control. Money can be made by more closely approaching product quality specifications. Process conditions can be continuously optimised provided good product quality control is in place. 

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