Cooling, loss

Temperature-induced runaways have many causes including loss of cooling, loss of agitation, and excessive heating. During a temperature-... 

Figure 9-1. Kinetics of the plasma-chemical pyrolysis of gas condensate (a) without cooling losses in the reactor (b) with cooling losses in the reactor.

Predicting losses is difficult, particularly losses through and around doors, jamb, sills, tramp air, cooling losses, and losses through conveyor equipment and gaps around it. Assigning safety factors or security factors to cover these matters requires experience and careful judgment. 

LHV - lower heating value, Pitt 8 - Pittsburgh No. 8, SAf - South African, a) Cooling losses to screen/bumer and low temperature losses. 

Its objectives include the elimination of severe accidents, including those related to power excursions, cooling loss, loss of external and backup power, or multiple... 

Compared with existing barrier systems, the additional mass transport in the grooves over the serew flights deereases the pressure level in the solids ehannel. Therefore, also the preceding feed zone has to build up less pressure, which results in a reduction of the abrasive wear and also in a reduction of the cooling losses in the feed zone. 

Small cooling losses in the feed zone and - compared with fast running extruders - also in the melting and mixing zone result in a better total energy efficiency and reduce the speeifie energy eonsumption. This helps to save natural energy resourees. 

In Fig. 6.27, the flue gas is cooled to pinch temperature before being released to the atmosphere. The heat releaised from the flue gas between pinch and ambient temperature is the stack loss. Thus, in Fig. 6.27, for a given grand composite curve and theoretical flcune temperature, the heat from fuel amd stack loss can be determined. 

The output from the turbine might be superheated or partially condensed, as is the case in Fig. 6.32. If the exhaust steam is to be used for process heating, ideally it should be close to saturated conditions. If the exhaust steam is significantly superheated, it can be desuperheated by direct injection of boiler feedwater, which vaporizes and cools the steam. However, if saturated steam is fed to a steam main, with significant potential for heat losses from the main, then it is desirable to retain some superheat rather than desuperheat the steam to saturated conditions. If saturated steam is fed to the main, then heat losses will cause excessive condensation in the main, which is not desirable. On the other hand, if the exhaust steam from the turbine is partially condensed, the condensate is separated and the steam used for heating. 

The solution obtained is evaporated somewhat, cooled in a vacuum desiccator and the crystals of the tetraoxo-acid filtered off too drastic evaporation causes formation of the heptaoxodiphosphoric acid by loss of water. 

Lucas reageut is prepared by dissolving 68 g. (0-5 mole) of anhydrous zinc chloride (fused sticks, powder, etc.) in 62 6 g. (0 6 mole) of concentrated hydrochloric acid with cooling to avoid loss of hydrogen chloride. 

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