Residence time at high temperature

Acenaphthylene and tetrabenzophenazine (40) are known to be appropriate starting materials hydrogenated or catalytically condensed aromatic hydrocarbons and pitches are also suitable (41). In thermal treatment of pitch, it is still a question whether short residence times at high temperatures or long residence times at low temperatures are preferable. In any case, the reaction should be homogeneous. The solvent may thus be important. 

The measured values of NO, and CO at the exit are plotted in Figure 5 vs. residence time at high temperature. These values of residence time were computed from the gas temperature profile down the tube, which was estimated from the wall temperature profile. The NO, decreases, and the CO increases with decreasing residence time as might be expected from kinetic considerations. These very low values of NO, and moderate values of CO are comparable in magnitude and trend with those of Bem-... 

At one plant, odors that are collected in a new rendering plant are piped 100 feet to the refuse fired steam generator for destruction. At other plants, flue gases from incinerating industrial and hazardous waste are blown into the furnace/boiler thus providing sufficient residence time at high temperatures. 

Higher Fermentation Yields. With a continuous sterilizer, proteins can be sterilized separately from carbohydrates and salts. The residence time at high temperature is short. There is less interaction and degradation of raw materials, resulting in higher fermentation yields. 

Sufficient particle residence times at high temperatures must be provided for steady agglomeration. 

Thus, the residence time at high temperatures should be reduced to minimize urea product losses through both reverse reactions of urea synthesis (Eqs. (3.15) and (3.16)) and biuret formation [13]. 

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