Product quality additives

The torque, screen force, specific energy and power could be regarded as end-point metrics and, therefore, a measure of process conformance and product quality. Additional examples are shown in Table 6. 

Additives are put Into the solution with the purpose of affecting the parameters of the process of crystallization and the product quality. Additives employed for aqueous solutions can be subdivided Into several groups ... 

If yes, additional review of good manufacturing practice and product quality requirements may be necessary. 

Step 1.3 Identify and Allocate Additional Resources. The audit may require external resources, such as laboratory facilities and possibly equipment for air sampling, flow measurements, energy measurements, and product-quality testing. 

A continuous stirred tank reactor (CSTR) is usually much smaller than a batch reactor for a specific production rate. In addition to reduced inventory, using a CSTR usually results in other benefits which enhance safety, reduce costs, and improve the product quality. For example ... 

Like VDA 6.1, AVSQ 94 does not include the requirements of ISO 9001. In this way issues of copyright are overcome, a practice shared by VDA and EAQF but not QS-9000. However, unlike VDA 6.1, AVSQ 94 follows the 20 elements of ISO 9001 with two additional elements, covering financial considerations and product safety. Those questions that go beyond ISO 9001 are marked and as every question is numbered it simplifies the evaluation process. A scoring method is employed to classify organizations in terms of a conformity index. Each question is awarded a point (0, 2.5, 5, 7.5, or 10), where 10 points means full compliance, 7.5 points means minor inadequacies, 5 points means inadequacies in application requiring improvement, 2.5 points means serious inadequacies in application, and 0 points is used for criteria not applied. Unfortunately all questions carry the same weight as no account of the impact of omission on product quality or customer satisfaction is included. 

These lists tell us something about the nature of quality records, especially by what is not included. Absent from the lists are policies, procedures, instructions, plans, specifications, and any other prescriptive documents. The records all have one thing in common they describe the results of some activity - the results of inspections, tests, reviews, audits, assessments, calculations, etc. However, these lists are dominated by records relating to product quality rather than to the operations of the quality system. In addition to audit records, the following records may need to be maintained to demonstrate the effectiveness of the quality system ... 

Solid particles have a distinct form, which can strongly affect their appearance, product quality and processing behaviour. Thus, in addition to chemical composition, particulate solids have to be additionally characterized by particle size and shape. Furthermore, particles can be generated at any point within the process. For example, nucleation occurs within a crystallization process and large particles are broken down to numerous smaller ones in a comminution process or within a drier. 

PEs, as other polymers, exhibit nonlinear behavior in their viscous and elastic properties under practical processing conditions, i.e., at high-shear stresses. The MFI value is, therefore, of little importance in polymer processing as it is determined at a fixed low-shear rate and does not provide information on melt elasticity [38,39]. In order to understand the processing behavior of polymers, studies on melt viscosity are done in the high-shear rate range viz. 100-1000 s . Additionally, it is important to measure the elastic property of a polymer under similar conditions to achieve consistent product quality in terms of residual stress and/or dimensional accuracy of the processed product. 

A survey of 500 plants that have implemented predictive maintenance methods indicates substantial improvements in reliability, availability and operating costs. The successful programs included in the survey include a cross-section of industries and provide an overview of the types of improvements that can be expected. Based on the survey results, major improvements can be achieved in maintenance costs, unscheduled machine failures, repair downtime, spare parts inventory, and both direct and in-direct overtime premiums. In addition, the survey indicated a dramatic improvement in machine life, production, operator safety, product quality and overall profitability. 

If the main fractionator bottoms temperature is limited to 690°F, adding a pool quench can provide additional LCO product recovery. Assuming there is no penalty for the bottoms product quality and there is available cooling capacity in the upper section of the fractionator, this incremental LCO yield is valuable. 

All equipment should comply with the relevant British and other Standards regarding dimensions, methods of determining ratings, compliance with safety regulations, robustness and general quality of manufacture [70]. BS.5750, Quality Systems, concentrates on the subject of product quality as it affects design, manufacture and installation. In addition to Standards, there are various Codes of Practice [71, 72]. 

The drawback is that the precipitation chemistry results in suspended solids that must be fluidized and removed from the boiler by BD, so a polymeric sludge conditioner (dispersant, deposit control agent) product and additional BD is required. The higher the FW hardness, the more BD is required because of the buildup of suspended solids, so there is a trade-off in terms of operating with lower quality FW and the resulting reduced efficiency. 

Traditionally, customers employ water treatment service companies simply as external contractors to assist in the maintenance of clean and efficient waterside surfaces in their various heating, steam generating, cooling, and certain industrial process systems. The customers benefit from genuine improvements in operating efficiency, reductions in maintenance time, and replacement component costs. In addition, where industrial processes are involved they often profit from an added-value, due to an improved product quality or reduction in manufacturing cost. 

A qualitative picture of the flow field created by an impeller in a mixing vessel in a single-phase liquid is useful in establishing whether there are stagnant or dead regions in the vessel, and whether or not particles are likely to be suspended. In addition, the efficiency of mixing equipment, as well as product quality, are influenced by the flow patterns prevailing in the vessel. 

The final element which regulations address is quality. Safety and fitness for purpose, as discussed above, are two of the characteristics that you would associate with a quality product. However, these characteristics alone would not describe a quality product. For any product or service to be considered quality you would also expect it to be reliable and consistent. Additionally in the context of medical products, quality means a requirement to demonstrate conformance to agreed specifications or applicable standards for content, purity and stability. Many organisations, from manufacturers to service providers, voluntarily apply quality assurance systems in order to more effectively meet their customers needs on a consistent basis. However,... 

One of the key challenges for this process is dealing with the wide range of contaminants in the waste HBr stream. Both inorganic and organic contaminants may be present. These contaminants are typically reactants and products of the upstream bromination process which generated the waste HBr. In addition, they may include corrosion products of upstream equipment or ionic materials present in the water used to scrub the gaseous bromination process effluent. The main concerns about contaminants in the feed streams are their effect on catalyst activity and stability and their effect on bromine product quality. 

Quantitative and qualitative anthocyanin composition must be known in order to determine the feasibility of application of new plant materials as anthocyanin-based colorant sources and to understand the relationships of structures and functions of anthocyanins. In addition, anthocyanin compositions of fruits and vegetables have also been used to detect adulteration of anthocyanin-based products - and as indicators of product quality. - ... 

Since many years, pectolytic enzymes have been widely used in industrial beverage processing to improve either the quality and the yields in fruit juice extraction or the characteristics of the final product [1,2]. To this purpose, complex enzymatic mixtures, containing several pectolytic enzymes and often also cellulose, hemicellulose and ligninolytic activities, are usually employed in the free form. The interactions among enzymes, substrates and other components of fruit juice make the system very difficult to be investigated and only few publications are devoted to the study of enzymatic pools [3-5], An effective alternative way to carry out the depectinisation process is represented by the use of immobilized enzymes. This approach allows for a facile and efficient enzymatic reaction control to be achieved. In fact, it is possible to avoid or at least to reduce the level of extraneous substances originating from the raw pectinases in the final product. In addition, continuous processes can be set up. 

Thin-layer chromatography is employed in many areas of QC and routine monitoring of product quality [458]. Fluorescence scanning, densitometry or videodensitometry are used for quantification. Not all polymer additives are amenable to TLC analysis. Some fatty acid amides are virtually insoluble in organic solvents and cannot be isolated by thin-layer or column chromatography. 

The purpose of this monograph, the first to be dedicated exclusively to the analytics of additives in polymers, is to evaluate critically the extensive problemsolving experience in the polymer industry. Although this book is not intended to be a treatise on modem analytical tools in general or on polymer analysis en large, an outline of the principles and characteristics of relevant instrumental techniques (without hands-on details) was deemed necessary to clarify the current state-of-the-art of the analysis of additives in polymers and to accustom the reader to the unavoidable professional nomenclature. The book, which provides an in-depth overview of additive analysis by focusing on a wide array of applications in R D, production, quality control and technical service, reflects the recent explosive development of the field. Rather than being a compendium, cookery book or laboratory manual for qualitative and/or quantitative analysis of specific additives in a variety of commercial polymers, with no limits to impractical academic exoticism (analysis for its own sake), the book focuses on the fundamental characteristics of the arsenal of techniques utilised industrially in direct relation... 

Such infrequent measurements make the control of the product quality difficult. At best, the operators have learned a set of heuristics that, if adhered to, usually produces a good product. However, unforeseen disturbances and undetected equipment degradations not accounted for by the heuristics still occur and affect the product. In addition, there are periods of operation when the final process step produces a degraded product in spite of near-perfect upstream operations. 

Consider again a batch polymerization process where the process is characterized by the sequential execution of a number of steps that take place in the two reactors. These are steps such as initial reactor charge, titration, reaction initiation, polymerization, and transfer. Because much of the critical product quality information is available only at the end of a batch cycle, the data interpretation system has been designed for diagnosis at the end of a cycle. At the end of a particular run, the data are analyzed and the identification of any problems is translated into corrective actions that are implemented for the next cycle. The interpretations of interest include root causes having to do with process problems (e.g., contamination or transfer problems), equipment malfunctions (e.g., valve problems or instrument failures), and step execution problems (e.g., titration too fast or too much catalyst added). The output dimension of the process is large with more than 300 possible root causes. Additional detail on the diagnostic system can be found in Sravana (1994). 

An extruder is a complicated device to control. Often the barrel is divided into three sections, and the temperature at the exit of each section determines the additional amount of electrical energy to be supplied. Most of the energy for heating is provided by the screw. The throughput is usually set by the rate at which the screw rotates, and is maintained constant. Work is currently being done on the effect of extruder operating conditions on product quality. Preliminary conclusions indicate that conditions should be kept as constant as possible if reproducible results are desired. 

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