Thermal first-stage

The Amoco Oil Company developed an ITSL process very similar to HRFs CTSL process. The main differences were the use of a higher-temperature, smaller-volume, thermal first-stage TLU and a lower temperature in the catalytic hydrotreater. This process was tested on HRFs bench-scale unit. The higher temperature in the TLU (820-850°F, 438-455°C) resulted in a 30 percent higher gas yield than HRFs CTSL process, whereas the lower temperature in the HTR (ca. 700°F, 370°C) contributed to longer catalyst life. However, the distillate yield for the Amoco process was considerably lower than that of HRFs CTSL process. 

The results of a set of computer calculations for a CBT plant with single-step cooling (i.e. of the first stage nozzle guide vanes) are illustrated in Fig. 5.2, in the form of (arbitrary) overall thermal efficiency (tjq) against pressure ratio (r) with the combustion temperature T. oi as a parameter, and in Fig. 5.3 as tjq against with r as a parameter. 

At the first stage of polyethylene thermal destruction the metallizing of polyethylene macroradical by the metal radical takes place. 

That the first stage of ordering (resistivity decrease) is correlated with excess vacancies not being in thermal equilibrium can be seen from measurement during isochronally lowering the temperature from the disordered state (0), which shows that atomic mobility is frozen below 280°C. 

Van Driesen and Stewart (V4) have reported temperature measurements for various locations in commercial gas-liquid fluidized reactors for the large-scale catalytic desulfurization and hydrocracking of heavy petroleum fractions (2500 barrels per day capacity). The hydrogenation was carried out in two stages the maximum and minimum temperatures measured were 774° and 778°F for the first stage and 768° and 770°F for the second. These results indicate that gas-liquid fluidized reactors are characterized by a high effective thermal conductivity. 

With respect to periodic reversal of flow direction, this seems to be competitive for low levels of smelter gas S02, probably under 4 vol%, at ambient temperature. If S02 is too high, thermal runaway can occur. A second, important application is to reduce S02 in the off-gas from a conventional acid plant. Use of flow reversal avoids the problem of reheating the gas leaving the first-stage absorber. 

Silva, G. S., A. G. Souza, J. R. Botelho et al. 2007. Kinetics study of norbixin s first stage thermal decomposition, using dynamic method../. Thermal Anal. Calorim. 87 871-874. 

One of the most remarkable attributes of Pechini-type routines is the behaviour of precursor resins (gels) upon heating. On the first stage of thermal decomposition of samples, being dried at approx. 120°C, they decompose forming very porous and voluminous sponge-cake-like materials [6], Probably, just at this temperature, a highly porous intermediate is... 

For the cooling of CUORE, it is foreseen the use of five PT 415 (Cryomech) pulse tubes (see Section 5.8). Each pulse tube delivers a cooling power of 40 W at 45 K at the first stage and 1.5W at 4.2 K. The high power requested by the first stages depends on the thermal load from the shields. 

The reaction of Curtius, which is especially to be preferred in the case of the higher members on account of the favourable solubilities of the intermediate products, involves as its first stage the preparation of the hydrazide from an ester (or acid chloride). The hydrazide is then converted, usually very readily, by the action of nitrous acid into the azide. In many cases it is more convenient to prepare the azide by treating an acid chloride with sodium azide previously activated with hydrazine hydrate.1 Azides easily undergo thermal decomposition, the two azo nitrogen atoms being eliminated as elementary nitrogen. In this way, however, the same radicle is formed as was invoked above to explain the Hofmann reaction ... 

The vendor shall provide eomplete performance curves, ineluding differential head, typieal efficieney, water NPSHR, and power expressed as funetions of capacity. The curves shall be extended to at least 120 percent of capacity at peak efficiency, and the rated operating point shall be indicated. The head curve for maximum and minimum impeller diameters shall be ineluded. The eye area of the first-stage impeller and the impeller identification number shall be shown on the curves. If applieable, the curves shall indicate viscosity corrections. Minimum flow (both thermal and stable), preferred and allowable operating regions, and any limitations of operation shall be indicated. 

Equation (25) may shed light on the general path of the iminoborane oligomerization. I propose the formation of cyclodimers to be the first stage of such oligomerizations. If a cyclodimer is stable to an excess of iminoborane, it will be isolated (Table III). Otherwise the cyclodimer is attacked by the excess iminoborane according to Eq. (25), and the borazine is formed via the Dewar borazine. In special cases, the Dewar borazine will be the final product. The first step determines the rate of such a sequence of reactions. If the cyclodimerization step becomes relatively fast, so that the first and the second step are comparable in rate, both the cyclodimer and the cyclotrimer will be found this is true for the thermal stabilization of sBuBNsBu. Catalysts for the cyclodimerization make the first step more rapid than the second one. 

The thermal decomposition process of AP particles is altered significantly when 10% LiF is added, as shown in Fig. 7.25. The decomposition of AP particles without LiF commences at about 570 K and 50% mass loss occurs at 667 K, which corresponds to the exothermic peak. The TG curve consists of a two-stage mass-loss process. The first stage corresponds to the first exothermic reaction at 635 K, and the second stage corresponds to the second exothermic reaction in the high-temperature region between 723 K and 786 K observed in the DTA experi-... 

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