Sources of gas

The evolution of gases, such as in dre example given above of dre formation of CO(g) in dre U airsfer of sulphur between carbon-saturated iron and a silicate slag, requires dre nucleation of bubbles before dre gas can be eliminated from the melt. The possibility of homogeneous nucleation seems unlikely, and the more probable source of gas bubbles would either be at the container ceramic walls, or on detached solid particles of the containing material which are... 

Gas pilots must be provided with a reliable source of gas which will remain available under any single contingency such as power or air failure. Pilots should be designed for the anticipated gas composition, which should be reasonably constant. 

Figure 15-21. Isolated compressor. Insulation is necessary because the compressor itself is a potential source of gas and requires the area to be classified.

In many developed and developing countries, there are now extensive natural gas supply networks, which provide secure and reliable sources of gas fuel. The user may require some pressure reduction and metering equipment... 

The potential for corrosion as a result of the reactions of noncondensable gases present in steam-water circuits is a major area of risk. The dissolved oxygen (DO) content of MU water is recognized as a primary source of gas entering a boiler system, and effective deaeration of MU and FW is therefore critical. 

Fig. 7.21 Mossbauer spectrum of ZnO using a source of Ga in ZnO single crystal (from [58])...

At low pressure, two main sources of gas are present <2w gas desorbing from surfaces and <2l gas leaking into the container from outside (imperfect tightness of gaskets, permeation, back-streaming from pumps, and so on). If Qt represents the sum of all these inputs, the change of pressure p with the time t is described by ... 

Long Rupture A section of pipe is removed leading to two sources of gas. Each section being vented in an opening whose cross sectional areas are equal to the cross sectional area of the pipe (e g., pipeline external impact and a section is removed). 

A gas-gathering and transmission system consists of sources of gas, arcs composed of pipeline segments, compressor stations, and delivery sites. The design or expansion of a gas pipeline transmission system involves capital expenditures as well as the continuing cost of operation and maintenance. Many factors have to be considered, including... 

Since the proved reserves of conventional natural gas have declined in recent years, the need for new supply options was of primary importance in the 1979 research program. Forty-four projects are being undertaken this year to further the development of four new sources of gas supply. They are o Unconventional Natural Gas... 

A steady source of gas supply is necessary, which is hard to come by for rare or pure gases. 

Two methods, EPA SW-846 8015 and 8015A, were, in the past, often quoted as the source of gas chromatography-based methods for measurement of the total petroleum hydrocarbons in a sample. However, the original methods were developed for nonhalogenated volatile organic compounds and were designed to measure a short target list of chemical solvents rather than petroleum hydrocarbons. Thus, because there was no universal method for total petroleum hydrocarbons, there were many variations of these methods. Recently, an updated method... 

Bing Blackdamp Blower Bold Bord-nnd-pillar Sec spoil heap On-delicient air. typically rich in CO> (synonym stythe Signilicant point source of gas entering mine workings Mine roadway tor dead-end room) from which rim-of-mine coal has been extracted A supported method of underground coal mining in which coal is extracted from a rectilinear network of bords. with pillars of intact coal left in place to support the roof. (synonyms pillar-and-stall. room-tuul-pillar. sioop-and-room)... 

Since initially Platform A will provide the major source of gas to meet the contractual commitments of the joint venture portners of the Australian North West Shelf gos project for the supply of gas to the State Energy Commission of Western Australia and also the early build-up in LNG production, and due to its location in on extremely remote port of Australia, every effort hos been made to produce a conservative and reliable design. 

Platform A will be the sole source of gas supply to the onshore plants for some years and therefore considerable emphasis was placed on selecting a conservative design, minimising corrosion by the use of corrosion inhibitors ond alloy materials ond reducing maintenance downtime by providing 100% standby for items which by their nature will require frequent maintenance or cleoning. 

It is impossible to eliminate all sources of gas in vacuum systems. Even in the best-designed and operated static systems at very low pressure, small leaks are present and slight outgassing occurs, and the resulting gas load has to be dealt with by the system s pumps. The usual sources of gas are indicated in Figure 4.1, and some general comments should be made before more detailed discussion in later sections. 

The pressure achievable in a vacuum system depends on the effective speed of the pumps and the total gas load in the system. In Chapter 4, the usual sources of gas (leaks, outgassing, permeation) were reviewed. At the outset, terms associated with gas leakage were discussed. It can be described by the equations of flow described in Chapter 2 and quantified... 

Source of gas, other than natural gas production from the lower 48 states, were arranged by Secretary Schlesinger in the following hierarchy of decreasing marginal attractiveness ... 

The other arrangement is called open split and is shown in Figure 11.7. The space between the column and the MS inlet is maintained at about atmospheric pressure by the use of a second source of gas and a separate vacuum. By controlling the amount of purge gas in this region, the column can be disconnected without shutting down the MS, and, alternatively, undesirable sample components such as large quantities of solvent can be removed before they enter the MS. 

Bromine oxide species can be formed in the polar boundary layer and areas with high salt levels such as the Dead Sea." ° The major source of gas-phase bromine in the lower troposphere is thought to be the release of species such as IBr, ICl, Br2 and BrCl from sea-salt aerosol, following the uptake from the gas phase and subsequent reactions of hypohalous acids (HOX, where X = Br, Cl,... 

Ballast bulb c. This is a bulb of large volume (at least 5 L), which permits small adjustments in pressure to be made by the addition or removal of small quantities of gas or air through the three-way stopcock Y at the bottom. One of the two lower arms of this stopcock is connected to the source of gas to be used (or to room air) the other is connected to a laboratory vacuum line or a vacuum pump. 

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