Processing performance

In the activated sludge process, performance is related to the food-to-microorganism ratio (F/M), which is the kg BOD appHed/d/kg volatile suspended soHds (VSS). 

For a soluble wastewater, the VSS is proportional to the biomass concentration. Process performance may also be related to the sludge age, which is the average length of time the organisms are in the process. 

Process performance is affected by temperature. The reaction rate decreases with temperature over a range of 4—31°C. As the temperature decreases, dispersed effluent suspended sohds increase. In one chemical plant in West Virginia, the average effluent suspended sohds was 42 mg/L during the summer and 105 mg/L during the winter. Temperatures above 37°C may result in a dispersed floe and poor settling sludge. It is therefore necessary to maintain aeration basin temperature below 37°C to achieve optimal effluent quahty. 

These universal concentrates are preferred if they can be used, because inventorying costs can be reduced it is not necessary to stock different concentrates for different colorants. In some performance polymers this concept is not appHcable because the universal vehicles have a negative effect on weathering, transparency, or processing performance. 

There are important economic consequences of a process being out of control for example, product waste and customer dissatisfaction. Hence, statistical process control does provide a way to continuously monitor process performance and improve product quahty. A typic process may go out of control due to several reasons, including... 

The performance of adsorption processes results in general from the combined effects of thermodynamic and rate factors. It is convenient to consider first thermodynamic factors. These determine the process performance in a limit where the system behaves ideally i.e. without mass transfer and Idnetic limitations and with the fluid phase in perfect... 

Relationship between Fluid Motion and Process Performance. 18-11... 

In any event, the users of the mixer can issue a mechanical specification aud determine the speed, diameter of an impeller, aud power with in-house expertise. Or they may issue a processes specification which describes the engineering purpose of the mixing operation and the vendor will supply a description of the mixer process performance as well as prepare a mechanical design. 

Not only is the type of flow related to the impeller Reynolds number, but also such process performance characteristics as mixing time, impeller pumping rate, impeller power consumption, and heat- and mass-transfer coefficients can be correlated with this dimensionless group. 

Relationship between Fluid Motion and Process Performance Several phenomena which can be used to promote various processing objectives occur during fluid motion in a vessel. 

There are no satisfactory specific guides for selecting mixing equipment because the ranges of application of the various types of equipment overlap and the effects or flow properties on process performance have not been adequately defined. Nevertheless, what is frequently done in selec ting equipment is described in the following paragraphs. 

Except as an index of respiration, carbon dioxide is seldom considered in fermentations but plays important roles. Its participation in carbonate equilibria affects pH removal of carbon dioxide by photosynthesis can force the pH above 10 in dense, well-illuminated algal cultures. Several biochemical reactions involve carbon dioxide, so their kinetics and equilibrium concentrations are dependent on gas concentrations, and metabolic rates of associated reactions may also change. Attempts to increase oxygen transfer rates by elevating pressure to get more driving force sometimes encounter poor process performance that might oe attributed to excessive dissolved carbon dioxide. 

A useful index of process performance is the oxygen uptake rate, OUR, that is calculated from the difference in oxygen concentration of the inlet air and the exiting gas. Also important is the respiration ratio defined as the carbon dioxide evolved divided by the oxygen consumed. 

FIG. 25-49 Effect of BSRT on biological treatment process performance, m = minimum BSRT. 

TABLE 25-44 Anaerobic Process Performance on Industrial Wastewater UASB/ Submerged filter (SF)/ FBR... 

The design and layout of the physical facihties that make up the processing-plant flow sheet are an important aspect in the implementation and successful operation of such systems. Important factors that must be considered in the design and layout of such systems include (1) process performance efficiency, (2) rehability and flexibihty, (3) ease and economy of operation, (4) aesthetics, and (5) environmental controls. 

Whiting, W.B., TM. Tong, and M.E. Reed, 1993. Effect of Uncertainties in Thermodynamic Data and Model Parameters on Calculated Process Performance, Industiial and Engineeiing Chemistiy Reseaieh, 32, 1993, 1367-1371. (Relational model development)... 

Is the deformation process performed on a single component or on two (or more) components simultaneously (6)... 

First part qualification. First part qualification is a process performed the first time a new bonded assembly is manufactured or the first time a new tool is used to manufacture a bonded assembly. First part qualification provides assurance that all of the aspects that control bond assembly quality, such as the design dimensions, detail part manufacturing techniques, tool dimensions, layup procedures and autoclave cure cycle parameters are correct and will produce a bond assembly that meets the engineering requirements. 

Some limitations are associated with UV radiation for disinfection. These include (1) The process performance is highly dependent on the efficacy of upstream devices that remove suspended solids (2) Another key factor is that the UV lamps must be kept clean in order to maintain their peak radiation output (3) A further drawback is associated with the fact that a thin layer of water (< 0.5 cm) must pass within 5 cm of the lamps. 

In process ventilation the target is to maintain defined conditions to ensure process performance (e.g., paper machine hoods). 

Proper design and construction of a local ventilation system must account for hood flow rate, contaminant generation process and rate, and the generated flow rate of contaminated air. Thus, knowledge about airflow mechanics, process performance, and the contaminant source is essential. The descriptions of different sources are included in Chapter 7 and here only short descripiions are included as necessary to identify different processes and source types. 

Requirement for audit of product realization and production processes to determine the effectiveness of process performance... 

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