III International Conference

METHOD OF CATALYTIC UTILIZATION OF AK TYPE MELANGESPP-III-40Kazakov V.V., Sozontov V.I., Salomakhina S.A.Close Joint Stock Company "Severodonetsk Azot Association", Severodonetsk, UkraineE-mail: ntc@azot.lg.uaUnder consideration is an ingenious method of utilization of melanges using catalyticdecomposition over various coals.The new approach to oxidizer utilization process will allow significantly reduce capitaland energy costs in case of carrying out utilization in abandoned mines.In the course of research work performed a number of distinctive features and potentialshave been identified with regard to process structure of AK type oxidizers (melanges)utilization by interaction with coal proceeding with temperature decrease which results intechnology simplification and cost reduction. The new approach to the oxidizer utilizationprocess will allow, along with great reduction in capital and operating costs, to develop a newunique competitive technology implementation of which will significantly decrease energyand metal intensity of the process.In interaction between coal and melanges there is observed gas generation and decreaseof the process temperature from 22 to 12−14 °C. In the initial period when melange is addedto coal insignificant emission of nitrogen oxides takes place caused by acid formation reactionwhich later stops. The process proceeds for 10 hours.Based on the experimental data it has been established that in interaction between coaland melanges the following reactions occur:N 2 O 4 + 4C = 4CO + N 2 + 102822 cal/mole (1)2HNO 3 + 5C = 5CO + N 2 + H 2 O + 119455 cal/mole (2)N 2 O 4 + 2C = 2CO 2 + N 2 + 184340 cal/mole (3)4HNO 3 + 5C = 5CO 2 + 2N 2 + 2H 2 O + 442700 cal/mole (4)Although reactions (1−4) are exothermic, energy required to break bonds between carbonatoms in coal which is equal to 124000−171700 cal/mole significantly exceeds overall heat ofreactions (1−4). It has been demonstrated that carbon atom formation from its moleculesreaches 60−70 % and reacted coal rate is 30−60 %.545