Gas generating rate

Mixing Calorimetry Instantaneous heat of mixing, AHMI)aNG Gas generation rates Isothermal, from ambient to 150°C Cannot test multi-phase systems... 

The DPT can be used to determine the pressure characteristics and gas generation rates where they occur during a decomposition reaction. The output from the test is a pressure-time plot that you can use to determine the volume of gas generated in the decomposition reaction. 

When the gas injection nozzle is in an unchoked condition, the pressure in the gas generator is equal to the combustion chamber pressure, i. e., pg = p The gas generation rate is determined by the pressure in the combustion chamber. When the gas injection nozzle is in a choked condition, the burning rate is determined by the gas injection nozzle area, A g, and then the pressure in the gas generator, pg, is determined by... 

The same assumptions apply for gas generation as for heat generation—that the sample is isotropic, that the gas generation rate does not vary with time or location in tne radiation area, and that the sample length is more than twice either of the other dimensions. 

When gas concentrations are calculated for these polymers, the combined effects of low diffusivity and higher gas generation rate result in the conclusion that gas diffusion out of the polymer has a small effect on the gas concentration in the polymer for samples in the 0.033 to 0.100-inch thickness range. As a further result, the calculated gas concentration for these samples increases linearly with time in the manner observed for the thicker polystyrene samples (Figure 19). The calculated gas concentration will start to approach an equilibrium concentration at some greater time, when the rate of gas diffusion out equals the rate of gas generation, but this point is evidently not reached within the time scale of the present experiments. 

Most screening tests are likely to lump all reactions that generate gas together. Tempered hybrid systems will not be distinguished but these will require a smaller relief area than a gassy system with the same gas generation rate. If the worst case is subsequently-found to be a tempered hybrid reaction, rather than a gassy system, then some reiteration to check that it is still the worst case may be required. 

The volumetric gas generation rate, QgLx is calculated as 9.8 m3/s (see A2.5), given the maximum rates of temperature and pressure rise from Table 3.1 before seal failure. 1 ". ... 

Peak gas generation rate, QGmax = 0.374 m3/s Void fraction, a = 0.129... 

Equation (11.3) demonstrates that the amount of hydrogen gas generated is twice that of oxygen gas. The gas generating rate can be calculated according to the Faraday s law ... 

From this evidence, it is important to remember that under otherwise equal conditions, the degree of reservoir fill should depend roughly linearly on the seal thickness and the gas generation rate directly below. In order to determine the physical process driving gas through a seal, two different models have been programmed based on diffusion and on Darcy... 

In this work, a number of catalyst samples were assessed in a series of screening experiments, vis-a-vis a commercially used imported catalyst (Table-1). On the consideration of the user s limitation and choice, the sample-8 (newly developed PDIL catalyst CD-ED-101) was chosen for detailed studies. Some of the important physical parameters considered by the users, are presented in Table-2. For a better comparison, these data for an imported catalyst (presently used in Indian plants) are also presented. The indigenous catalyst was evaluated for activity, ethylene selectivity and ethylene gas generation rate, using wide ranges of feed compositions and space velocities. These data have been presented in Table 3. 

The majority of chemical processes is performed in pressure vessels. As has been outlined in Section 4.4 in detail, the heat release due to a chemical reaction may lead to a strong temperature increase if it is not adequately controlled. In the case of volatile substances this rise in temperature results in a significant vapour pressure increase. In some cases a higher permanent gas generation rate due to a decomposition reaction may additionally occur. One or both will cause a strong pressure rise if the process is performed in a closed system. Therefore the pressure vessel must be protected against... 

All further considerations shall remain limited to pine vapour phase systems, because the design of hybrid and gas generating systems requires the additional information of the individual permanent gas generation rate. Such systems must each be characterized experimentally before the first run on the plant This must be followed by the second step of assessing the compatibility of process and plant design. 

Figure 3.2. Relationship between hydrogen gas generation rate and electrical current.

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