Processing line upstream

Processing line, upstream Refers to material movement and auxiliary equipment (dryer, mixer/blender, storage bins, etc.) that exist prior to plastic entering the main fabricating machine such as the extruder. 

Overall, therefore, the routine manufacture of a biopharmaceutical product is initiated by large-scale culture of its producing cell line (upstream processing). Subsequent to this, the product is recovered, purified and formulated into final product format. These latter operations are collectively termed downstream processing and are described in Chapter 6. 

In order to reduce the cooling level to the barrel zone, a metering valve was placed in the water line upstream of the solenoid valve as shown in Fig. 12.8(b). Now when the controller opens the solenoid valve, a much lower quantity of water and thus cooling is available to the barrel zone. Prior to this modification, the barrel temperatures oscillated 10 °C about the set point temperature. After the modification, the temperature oscillations were reduced to about 3 °C, and the profitability of the process was improved due to the minimization of resin consumption. 

Fish meat debris by-produced on fish processing lines, unutilized fish meat, and upstream salmon meat are important sources of proteins, but have... 

The VariCol approach, as introduced by Ludemann-Hombourger, Bailly, and Nicoud (2000), increases the flexibility of the continuous separation system by an asynchronous movement of the injection and withdrawal ports. Within a complete process cycle, this leads to mean numbers of columns per section that are typically non-integer. As the minimum number of columns per section in an SMB system is 1, it is possible in VariCol systems to reduce the mean number to virtually any value less than 1. Owing to the asynchronous shift of the inlet and outlet lines in a VariCol process it may even happen that, during a certain interval, there are no columns in a section. In this case the inlet and outlet lines of this section coincide in one valve block. By placing the outlet lines upstream from the inlet lines a pollution of the product lines is avoided. 

As emphasized throughout this book, many different types of auxiliary equipment and secondary operations can be used to maximize overall processing plant productivity and efficiency. Their proper selection, use, and maintenance are as important as the selection of the processing machines (injection molder, extruder, etc.). The processor must determine what is needed, from upstream to downstream, based on what the equipment has to accomplish, what controls are required, ease of operation and maintenance, safety devices, energy requirements, compatibility with existing equipment, and so on. This chapter provides examples of this selection procedure and its importance in evaluating all the equipment required in a processing line. Details on all the equipment that is available can be obtained from plastics industry trade publications, usually compiled in an annual issue. These and other pertinent publications are included in the reference section (1-4, 33, 271-289). 

These monitors are located upstream of the safety relief valves on each pair of main steam lines. Detectors are mounted close to the process line to detect radioactivity due to a steam generator tube rupture. These monitors meet the requirements for Regulatory Guide 1.97 Category 2 instrumentation. 

For the tandem arrangement gas seal, a primary seal vent must be pro vided to vent the leakage across the process side seal. This vent ma> lie to flare or other suitable gas disposal point. The back pressure under nor mal conditions should be kept to a low value. A small amount of back pressure is recommended to keep a positive differential across the see ondaiy seal. Leakage measurement may be provided in the vent line to provide health monitoring of the primary seal. Unfortunately, the rotameter, which would be the obvious choice, should not be used because of its lack o reliability. If an orifice or needle valve is used to set the back pressure to the seal vent, pressure upstream of the restriction can be measured for a relative flow measurement. This type of reading does provide trend data that may be used to judge the seal s performance. 

Tolerance The penalty for having an unbalanced wall is the reduction of tolerance control. Tolerance limits are usually at least doubled. Also, with certain plastics it is more difficult to process them, such as those with low melt strength. Although the balanced wall is the ideal, having it is not always possible. Recognize that the unbalanced wall can be extruded with proper die design and control of the extruder line from upstream to downstream equipment. 

The upstream processing element of the manufacture of a batch of biopharmaceutical product begins with the removal of a single ampoule of the working cell bank. This vial is used to inoculate a small volume of sterile media, with subsequent incubation under appropriate conditions. This describes the growth of laboratory-scale starter cultures of the producer cell line. This starter culture is, in turn, used to inoculate a production-scale starter culture that is used to inoculate the production-scale bioreactor (Figure 5.7). The media composition and fermentation conditions required to... 

Figure 5.7 Outline of the upstream processing stages involved in the production of a single batch of product. Initially, the contents of a single ampoule of the working cell bank (a) are used to inoculate a few hundred millilitres of media (b). After growth, this laboratory-scale starter culture is used to inoculate several litres/tens of litres of media present in a small bioreactor (c). This production-scale starter culture is used to inoculate the production-scale bioreactor (d), which often contains several thousands/tens of thousands litres of media. This process is equally applicable to prokaryotic or eukaryotic-based producer cell lines, although the bioreactor design, conditions of growth, etc., will differ in these two instances...

For aerobic gravity sewers, procedure 4 is the ultimate calibration of the sewer process model. This is based on procedures 1 to 3 using information from upstream and downstream wastewater samples and by including local sewer systems and flow characteristics, temperature and DO concentration values of the wastewater in the sewer. Example 7.2 outlines the results of calibration and validation performed on a 5 km intercepting sewer line. 

Often an improvement in one section of a line or plant will cause the rate-limiting section to shift to either an upstream or downstream process. These types of projects often have considerable value associated with them because of the multiple bottlenecks that exist. 

The source of water samples was a 4-m3/h pilot plant on the Seine River located upstream from Paris, France. The background organic concentration ranged from 2 to 3 mg/L. The process, shown in Figure 1, included an upflow solids contact clarifier (Pulsator, Degremont, Rueil Malmaison, France) followed by rapid sand filtration (RSF). The effluent of the RSF was then split into four lines, which received various levels of ozonation followed by granular activated carbon (GAC) adsorption. Postchlorination (0.2 mg/L residual after 1 h) was used for bacterial control. 

NONE No Flow 1. Flow stopped upstream. 2. Line blockage OT the isolation valve shut in error. 3. Line fracture. No absorption in column. Entire process stops as tail-gas Row As for I. Pressure buildup in pipe and secon cooler. As for I. Gases escape into the surroundings. a) Ensure liquid feeds to absorber and Stops.Other process units shut down. b) Install LOW FLOW ALARM onto the FIC. Covered by a) and b). dary c) Install kick-back on upstream pumps and ensure pressure relief system is adequate. Covered by a) and b). d) Ensure regular patrolling of feed transfer lines. e) Plant emergency shutdown procedures. 

The best approach to investigating power quality problems is to first examine the power quality to the affected equipment at a point as close as possible to the equipment. If power quality anomalies are noticed, then move upstream with a process-of-elimination plan. That is, at each location determine if the problem is due to load-side anomalies or line-side problems. Even though this process is time consuming and perhaps cost ineffective, valuable information can be obtained. Understanding and solving power quality problems is rarely quick and easy. 

As in a continuous flow process downstream apparatus is directly linked to upstream devices, the complete production line is interrupted in case of a failure upstream. It will be examined if this failure behavior can be corrected either by the design of several parallel lines or by supplying buffer tanks, additional spare pumps, machines,... 

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