Introducing the supercritical water oxidation technology into the clean combustion of coal to solve serious problems of low combustion efficiency and pollution of traditional coal combustion

this paper analyzed the reaction characteristics of coal in two different oxidizing atmosphere of air and supercritical water. Furthermore

based on different reaction paths and by means of the energy utilization diagram methodology

the energy conversion characteristics of coal oxidizing in different atmosphere were analyzed

and the new mechanism of energy release of coal oxidizing in aqueous phase was revealed. Finally

the exergy analysis of practical application process of two kinds of oxidation was carried out. The results showed that the aqueous phase oxidation of coal reduced chemistry exergy level from 1 to 0.83

this is to say

the grade difference between chemistry energy and heat source was decreased

indicating that it reduced the irreversible loss of the conversion process from chemical energy into physical energy

exergy losses decreased about 6.04% and thermal exergy increased by 5.25%. The exergy efficiency of coal oxidation in supercritical water was as high as 80.1% about 24.2% higher than oxidation in air

and thus it can greatly improve the exergy efficiency.