Gas profiles

Figure 6.30 shows the grand composite curve plotted from the problem table cascade in Fig. 6.186. The starting point for the flue gas is an actual temperature of 1800 C, which corresponds to a shifl ed temperature of (1800 — 25) = mS C on the grand composite curve. The flue gas profile is not restricted above the pinch and can be cooled to pinch temperature corresponding to a shifted temperature of 145 C before venting to the atmosphere. The actual stack temperature is thus 145 + 25= 170°C. This is just above the acid dew point of 160 C. Now calculate the fuel consumption ...

Thermal-programmed solid insertion probe mass spectrometry (TP-SIP-MS) has been proposed [247,248], in which the solid insertion probe consisting of a water-cooled microfumace enters the mass spectrometer via an airlock. The sample is contained in a small Pyrex tube (i.d. 1 mm, length 20 mm). The TIC trace gives a characteristic evolved gas profile for each compound in a mixture of materials, and the mass spectra associated with each TIC peak give a positive identification of that component as it is vaporised. TP-SIP-MS is appropriate for analysis of small solid particles which are volatile, or produce volatile decomposition products. The technique is a form of evolved gas analysis. 

In this work, consideration has been given to the significance of the peaks and shoulders in the gas profiles from PTP and PTO to provide insight into the processes of coal desulfurization. 

Rocholl, A., Heusser, E., Kirsten, T., Oehm, J., Richter, H. (1996) A noble gas profile across a Hawaiian mantle xenolith Mantle-derived cognate and accidental noble gas components and evidence for anomalous krypton isotopes. Geochim. Cosmochim. Acta, 60, 4773-83. 

Figure 1.3 Evolved gas profiles (EPG) for PTFE, Aflas and PP upon heating at 10 °C / min. Ordinate axis values are arbitrary and simply relative...

TG/FTIR Total Integrated (Absorption) Values of the Specific Gas Profiles in Nitrogen and Air Atmospheres... 

Harmett, H. E., and Seitzinger, S. P. (2003). High-resolution nitrogen gas profiles in sediment porewaters using a new probe for membrane-inlet mass spectrometry (MIMS). Mar. Chem. 83, 23-30. 

Radial flows probably are not the main cause of gradients but can help in reproducing the gas profile. 

Figure 3 Series of isothermal conversion experiments of M0O2 into M0O3 observed by in-situ time resolved EXAFS. The oxygen gas profile is given at the bottom. The inset shows the same data in a re-normalised time scale...

KUR 00] Kurdikar D., Fournet L., Slater S., et al, Greenhouse Gas Profile of a Plastic Material Derived from a Genetically Modified Planf , Journal of Industrial Ecology, vol. 4, no. 3, p. 107,2000. 

Under a uniform gas profile (type T), the steady-state response function is given by the power law ... 

Gas profile in the active film (a) uniform and (b) moving boundary. 

In the method of aspirator IMS (alMS), ions are introduced into a flow of gas between two parallel plates with a constant electric field (Figure I.4b). ° The ions move through the laminar gas profile toward a collector plate, which is fitted with... 

Ten impedance measurements were averaged for each data point, providing a good SNR for the 61 kHz impedance data. For the 12 MHz data, the SNR is obviously lower. Due to the parasitic capacitances in the system, the SNR decreases strongly for higher frequencies. However, at least for lower sensor temperatures where the sensor has a higher sensitivity, the gas profile is still recognizable in the data acquired at 12 MHz. 

Figure 9. Sensitivities at 61 kHz (left) and 12 MHz (right) during test gas profile.

Decomposition of poly(ethylene terephthalate) as recorded using TG-DTA-FTIR. (A) Simultaneous TG-DTA curves. (B) IR absorption spectra of the evolved gases at various temperatures. (C) Specific gas profiles of the evolved gases. 

The internals of the bubble column reactor may have a dramatic impact on the flow patterns of the bubbles and the liquid. Companies have not divulged details about the internals to date. Some details of the US DOE pilot plant (22.5 inch 0.57 m diameter) have been published [ 106]. In this report the dimensions of the cooling tubes, their location, and their number are provided. These cooling coils occupied about 10% of the total volume of their commercial reactors slurry volume. The gas holdup and bubble characteristics as well as their radial profiles were determined in a column that was about the size of the US DOE reactor [107-109]. Dense internals were found to increase the overall gas holdup and to alter the radial gas profile at various superficial gas velocities. The tube bundle in the column increased the liquid recirculation and eliminated the rise of bubbles in the wall region of the column. These results indicate that further studies of bubble column hydrodynamics are directed toward larger scale units equipped with heat exchange tubes. 

Treatment tabie A depth-time and breathing gas profile designed to treat decompression sickness. 

Kurdikar D., Foumet L., Slater S.C., Paster M., Gemgross XU, Coulon R. Greenhouse gas profile of a plastic material derived from a genetically modified plant, J. Ind. Ecol. 4 (2001) 107. 

Figure 11 suggests that their formation is not necessarily coupled. Third, the difference in the gas profiles is relatively small and consistent with the higher temperature conditions (more extensive reactions) in the data on the left. There is no evidence of a change in the decomposition mechanism between the two sets of conditions shown. 

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