氯酸钠电化生产的歧化反应热计算

Calculation of disproportionation heat in producing sodium chlorate by electrolysis

电解氯化钠制氯酸钠的过程会产生歧化反应热，歧化反应热的多少关系到移走这部分热量的换热器设计和这部分热能的开发利用价值。但由于氯酸钠电化生产过程能量衡算复杂（既有电功、又有化学反应热效应、相变热），一般化工设计类书籍中，很难找到这类反应的能量衡算方法。对氯酸钠电解歧化反应热的理论计算和实际测算方法进行了探讨，给出了合理、简便的理论计算和实际测算方法。并且两种方法计算结果相差较小。然后利用已有的实际生产数据进行了佐证，最后综合计算结果和已有生产数据，得出电解电能30％～35％转化为可利用的歧化反应热，以氯酸钠产量计歧化反应热为5．55×10^6～6．34×10^6kJ／t的结论。数据可靠性满足设计开发者使用。

Process of producing sodium chlorate by electrolyzing sodium chloride will generate redundant disproportionation heat. The quantity of disproportionation heat relates to the design of heat exchanger to move away this part of heat and it also relates to the estimated value of developing this part of heat. But calculation of energy balance in electrolysis reaction is very complicated because it contains imported electric energy, critical heat （water evaporation）, and pyrometric effect of chemical reaction. So it is difficult to find out the calculation method for this kind of electrolysis reaction in general chemical desgin books. The theoretical and practical calculation methods for disproportionation heat were discussed. Simple and reasonable methods, which had small difference in calculation results were given out. Then the methods were testified by the existing production data. At last, the conclusion that 30% - 35% electric energy of electrolysis converted to utilizable disproportionation heat and the disproportionation heat was 5.55×10^6 - 6.34×10^6 kJ/t calculated according to sodium chlorate output had been obtained by combining the calculation results and the existing production data. The data is reliable enough for designers to use.