Gas metering

In situ control and calibration of flare and other gas metering systems is performed by gaseous tracers using the transit time method without affecting the normal production. Details about methodology are given in / /. 

Liquid Displacement Gas Meter Provers. The Hquid displacement prover is the most prevalent standard for the caHbration of flow meters at low to moderate gas flow rates. The method consists of displacing a known volume of Hquid with gas (Fig. 2). Gas entering the inverted beU causes it to rise and a volume increment can be timed. Typical prover capacities are 1 m or less although capacities as large as 20 m are available. Accuracies can be on the order of 0.5% of actual flow rate. 

Fig. 12. Foam extmsion line A, resia feed B, extmder for melting and gas iacorporation C, gas supply D, gas metering and compression E, optical wiadows F, cooling extmder and G, die. P represents a pressure gauge. Courtesy of Polymer Processing Institute.

Some of the early Thiokol soHd mbbers are stiU made and used in printing roUs, solvent-resistant spray hose, gaskets, and gas-meter diaphragms. Many of the polysulfide products have been in use since the 1940s with an exceUent track record. Continuing improvements in technology keep these products competitive. 

Rubber Articles. The soHd polysulftde mbber products, Thiokol FA and Thiokol ST, are used ia the manufacture of printing roUers, printing blankets, gas meter diaphragms, O-rings, and specialty molded items. 

Segmental and eccentric orifices are frequently used for gas metering when there is a possibility that entrained liqiiids or solids would otherwise accumulate in front of a concentric circular orifice. This can be avoided if the opening is placed on the lower side of the pipe. For hquid flow with entrained gas, the opening is placed on the upper side. The pressure taps should be located on the opposite side of the pipe from the opening. 

A wet gas meter such as No. S-39465, E. H. Sargent and Company, is satisfactory. This meter need not be a permanent part of the apparatus. It is used only to calibrate the flowmeter. 

In the sampling train itself, the gas flow must be measured to determine the sample volume. Parhculates and gases are measured as micrograms per cubic meter. In either case, determination of the fraction requires that the gas volume be measured for the term in the denominator. Some sample trains contain built-in flow-indicahng devices such as orifice meters, roto-meters, or gas meters. These devices require calibration to assure that they read accurately at the time of the test and under test conditions. 

Metering flare gas is important for loss accounting and for control of steam injection. A special requirement for flare gas meters is low pressure drop and the ability to continue functioning in fouling conditions. The flare gas metering methods listed below have been used with varying degrees of success. 

Other types of flowmeters that are applicable to flare gas metering include... 

FIGURE 13.39 Example of a measurir(g- with water removal upstream of the gas-metering device ... 

What monitoring devices are needed for die storage area e.g, combustible gas meter, organic vapor imalyzer, etc. 

Similar to the pH meter, gas meters employ specific ion electrodes. The electrodes generate a potential proportional to the activity of a specific ion in solution. The calibration is achieved in standard solution and results read in mV or concentration in mg/L or ppm on the meter. The water can be adapted to monitor the concentration of carbon dioxide, hydrogen sulfide, ammonia, chloride, calcium, potassium and sodium to name a few. 

These are the traditional gas meter that incorporates diaphragms contained within a steel case. The diaphragms are alternately inflated and then deflated by the presence of the gas. The movement of the diaphragms is linked to valves that control the passage of gas into and out of the four measuring compartments. 

The main application is in the form of tinplate. Apart from its use for containers mentioned earlier, tinplate is made into domestic and industrial kitchen equipment, light engineering products and toys. For most of these purposes, coatings in the thickness range 0-4-2-5 im, with or without organic finishes, are used. For returnable containers and more permanent articles such as fuel tanks and gas-meter cases, heavier coatings of up to 15 m may be necessary. 

The major process parameters at selected periods in the four experiments are listed in Tables II, IV, VII, and VIII. Carbon recoveries ranged from 63 to 91%. Most of the losses occurred in connection with the recycle compressor system, and they decreased correspondingly the volume of product gas metered. Such losses, however, did not affect significantly the incoming gas to the main reactor or reactor performance. 

I placed a weighed quantity of sodium borohydride in a flask and attached it to a dropping funnel which contained water. The outlet from the flask was connected to a gas meter. The entire assembly was placed behind an explosion screen, since I did not know how violent the reaction might be. 

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