Ease of Control

Other advantages of gravity beds include flexibility in gas and sohds flow rates and capacities, variable retention times from minutes to several hours, space economy, ease of startup and shutdown, the potentially large number of contacting stages, and ease of control by using the inlet- and exit-gas temperatures. 

In order to avoid the need to measure velocity head, the loop piping must be sized to have a velocity pressure less than 5% of the static pressure. Flow conditions at the required overload capacity should be checked for critical pressure drop to ensure that valves are adequately sized. For ease of control, the loop gas cooler is usually placed downstream of the discharge throttle valve. Care should be taken to check that choke flow will not occur in the cooler tubes. Another cause of concern is cooler heat capacity and/or cooling water approach temperature. A check of these items, especially with regard to expected ambient condi-... 

The centrifugal pump is a versatile unit in the process plant, since its ease of control, non-pulsing flow, pressure limiting operation fits many small and large flow systems. 

The turbine has the features of (1) variable speed operation, (2) ease of controls, (3) nonsparking operation for hazardous environment, (4) enclosed operation suitable for corrosive atmospheres, (5) operation without electrical power, (6) small space requirements per horsepower, (7) steam use under almost any condition to suit plant heat bal-... 

Versatility (e.g. very small flames, localized heating) Wide turndown of burners Clean combustion gases Ease of control... 

Among the advantages of electric motor drive are compactness and ease of control. The internal combustion engine is preferred for mobile units, emergency standby units, or where electric power is not available. 

High gas solubility Weak solvation High diffusion rates Ease of control over properties Good mass transfer Readily available Possible heat-transfer problems... 

Ease of control of temperature in each stage, since each operates in a stationary state heat transfer surface for this can be easily provided ... 

In practice, two reactor types have proven to be capable of meeting these requirements as well as the need for high reliability in operation and ease of control the stirred autoclave and the loop reactor (see Table 37.1). 

Human error is the most frequent cause of the loss of containment. Training and certification of personnel on critical procedures are permanent considerations. Also some other inherent safety principles, like ease of control, making status clear, tolerance and making incorrect assemply impossible, come into play here. 

Ease of Control safe process structure heat of reaction... 

A higher temperature ( 900°C) technique involves use of the molten metal halides as a flux (26). Growth from KC1 under slow cooling conditions for times on the order of one week produced crystals on the order of 1mm in diameter (27). The small size of the product crystals in the above experiments is a result of the limited solubility of the product in the flux. The advantages include mild conditions of product separation, and ease of control of product stoichiometry. 

Stimulation fluid is a treatment fluid prepared for stimulation purposes, although the term most commonly is applied to matrix stimulation fluids. Most matrix stimulation fluids are acid or solvent-based, with hydrochloric acid being the most common base due to its reaction characteristics and its relative ease of control. Matrix stimulation is a process of injecting a fluid into the formation, either an acid or solvent at pressures below the fracturing pressure, to improve the production or injection flow capacity of a well. 

Dividing the reactor into sections also has the advantage that the intermediate temperature can be adjusted independently of the inlet temperature thus an optimum temperature distribution can be achieved. In this example we can see that the furnaces where heat is transferred and the catalytic reactors are quite separate units, each designed specifically for the one function. This separation of function generally provides ease of control, flexibility of operation and often leads to a good overall engineering design. 

Given its convenience for self-implantation, the high permeability, and its ease of controlling delivery, the vaginal route may offer opportunities... 

The single most important characteristic of the sol-gel preparation of catalytic materials is its ease of control that translates into the following advantages ... 

It has been pointed out by Anderson (1) that deviations from stoichiometry in a compound must be accompanied by defects in the lattice of that compound. The metal hydrides are particularly suitable for studying such defects because of their unusually wide variations from stoichiometric compositions, and because of the ease of controlling the composition of the hydride and thereby the concentration of defects by simply varying the hydrogen pressure. 

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