Flue gas, analyses

The power train (Figure 8-10) was eommissioned in May 1989. Table 8-1 provides data on the maehine in question. Tables 8-2 and 8-3 show flue gas analysis from the regenerator to the gas expander turbine inlet and the relevant metallurgy, respeetively. There are many possible failure modes in gas expanders, whieh inelude erosion, eatalyst deposition, and exeessive meehanieal vibration. Obviously, these faetors may also eause power loss, and some power trains do indeed fall short of produeing the expeeted power. Nevertheless, in some eases operation at off-design expander system eonditions eould be the primary eause of performanee defieieneies. 

Figure 1. Excess air can be determined from flue gas analysis and hydrogen-to-carbon weight ratio of the fuel.

Most combustion equipment is not controlled by means of a feedback from flue gas analysis but is preset at the time of commissioning and preferably checked and reset at intervals as part of a planned maintenance schedule. It is difficult to set the burner for optimum efficiency at all firing rates and some compromise is necessary, depending on the control valves used and the control mode (e.g. on/off, fully modulating, etc.). 

The sample taps must be bled adequately before samples are collected. A reliable flue gas analysis is important an extra sample can be collected. The laboratory should retain the unused samples until all analyses are verified. 

The coke calculation showed the hydrogen content to be 9.9 wtVt. As discussed in Chapter 1, every effort should be made to minimize the hydrogen content of the coke entering the regenerator. The hydrogen content of a well-stripped catalyst is in the range of 5 wt% to 6 wt%. A 9.9 wt% hydrogen in coke indicates either poor stripper operation and/or erroneous flue gas analysis. 

Recorders measure steam flow, air flow, FW flow, drum water level, steam temperatures, flue gas temperatures, flue gas analysis and smoke opacity. 

Additionally, comparison of MU water usage and steam production with chemical treatment supplied, fuel consumption records, and flue gas analysis will provides early warning signs of deposit formation. Water analysis records can indicate problems of process contamination, BW carryover, and inadequate oxygen scavenging (and therefore the potential for corrosion). 

One of several different types of flue-gas analysis equipment (such as electronic, Fyrite, or Or sat types). They are used to determine boiler fuel combustion efficiency. 

In a test on a furnace fired with natural gas (composition 95 per cent methane, 5 per cent nitrogen) the following flue gas analysis was obtained carbon dioxide 9.1 per cent, carbon monoxide 0.2 per cent, oxygen 4.6 per cent, nitrogen 86.1 per cent, all percentages by volume. 

Note the flue gas analysis is reported on the dry basis, any water formed having been condensed out. 

It would also be of interest to carry out an analysis of what happens to the response time of the conversion gas from the moment it is converted until it reaches, and at the same time is monitored by, the flue gas analysis system. This response delay is a... 

For each mole of C burned, one mole of CO2 is formed. From the fuel analysis used there are 110.6 moles C per 100 moles of fuel, and there are also 110.6 moles of COi formed from the 110.6 moles C in the fuel. From the flue gas analysis, there are 100/10.4 = 9.62 moles of dry flue gas per mole of C02. The 100 moles of fuel will then yield 110.6 x 9.62 = 1,064 moles of dry flue gas. By the application of the mole method, an important value has been quickly determined through knowing only the flue gas analysis and the fuel analysis. 

From the flue gas analysis, the molecular weight of the dry flue gas can be easily determined, as follows ... 

Assume that all oxygen not reported in flue gas analysis reacted with hydrogen in the coke to form water. All oxygen is reported as 02 equivalent. Assume that air is 79.02% nitrogen and 20.98% oxygen. 

Figure 3 Flue gas analysis and temperature measurement system.

Explain the difference between flue gas analysis and Orsat analysis wet basis and dry basis for a gas. 

Pure carbon is burned in oxygen. The flue-gas analysis is ... 

If a dry flue gas analysis shows some. CO, as in the following hypothetical analy-... 

The values of C, H, S, and O can be taken from the fuel or flue-gas analysis. If the heating value of a fuel is known and the C and S are known, the approximate value of the net H can be determined from the Dulong formula. A general relation between the gross heating and net heating values is... 

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