• 化工学报 •     Next Articles

STUDIES ON THE PREPARATION OF HUMIC ACID BY THE MILD OXIDATION OF BROWN COAL IN AIR- FLUIDIZED BED UNDER PRESSURE

(Chemical Technology and Engineering)Peking Institute of Petroleum Technology PANG KUEI-szu, CHU YA-CHICH   

  • Online:1966-03-25 Published:1966-03-25

加压流化床中褐煤空气氧化制取腐殖酸的研究

庞桂赐,朱亚杰   

  1. 北京石油学院 ,北京石油学院

Abstract: In order to increase the reaction rate in the formation of humic acid by air-oxidation of brown coal with the purpose of seeking a scientific as well as technical basis to see whether it is possible to adopt a continuous process in stead of the ordinary batch one, the oxidation of Tza-Lai-Nor brown coal in air-fluidized bed under pressure has been studied. Experiments were carried out in a simple fluidized-bed reactor made from alloyed steel. Effects of both pressure from 0 to 20 gauge atmospheres and temperatures from 150 to 1901-, on the rate of formation of humic acid were investigated. Experimental results have shown that the former has a more significant effect under which the time required for the oxidation process as the humic acid content of oxidized coal has attained a value of about 80% is in reverse proportion to absolute pressure of the system. On the other hand, effect of temperature has been shown playing also an important rule in the increase of rate of oxidation reaction. Owing to the constructional restriction of the reactor it is rather difficult to dissipate the huge amount of heat of reaction at some particular moment in the early period of oxidation, so that the seemingly maximum temperatures at corresponding pressures can hardly be further raised. Under the conditions of our experiments the most favorable technical data have been found to be. 20 atmospheres and 170℃, oxidation period 1.5 hrs. or alternately 5 atmospheres and 190℃, oxidation period 2.5~3 hrs. In both cases the humic acid contents of oxidized coals are in the range of 85~87% , and the carboxylic radical values are about 2.1~2.4 milliequivalents per gram of moisture-ash-free oxidized coal.

摘要: 为了加速空气氧化生成腐殖酸的反应速度,以及为采用连续过程的可能性提供科学和工艺的依据,在加压流化床中进行了札賚诺尔褐煤空气氧化制取腐殖酸的研究。在本试验装置中考察了压力(0~20大气压)、温度(150~190℃)等条件对腐殖酸生成速度的影响。试验结果指出:压力对于腐殖酸的生成速度有显著影响,达到腐殖酸含量为80%左右所需要的时间与压力成反比关系;温度也是影响腐殖酸生成速度的重要因素,但在该种反应器中,由于结构的限制,散出在氧化早期所产生的大量反应热是很困难的,因此反应温度难以进一步提高,而存在一个“高限温度”。 在本文试验条件下最佳的工艺条件为:20大气压,170℃,反应1.5小时;或为5大气压,190℃,反应2.5~3小时。在这两种情况下,氧化煤中腐殖酸含量为85~87%左右,羧基含量为2.1~2.4毫克当量数/克无灰无水氧化煤左右。