Removing Sulphur In Coal By Extraction And Oxidation Under Ultrasonic And Microwave

In China, Coal occupies above 2/3 in the primary energy production and consume. With the development of Chinese economics, the quantity of consuming energy will improve strongly. The polluted problem caused by the SOX emission during the course of coal burning is more and more serious, so it is urgent that finding a mild technology would be used to remove sulphur in coal sufficiently.In the thesis, six kinds of high sulfur coals from Beijing, Wangzhang, Yanzhou, Linfen, Yima and Datong were selected, the effect of raw coal desulphurization was investigated by organic solvent extraction and inorganic oxidation process under ultrasonic and microwave irradiation.The high sulfur coal was treated by organic solvent under ultrasonic or microwave field. The influence of treating conditions, including the size of coal, extraction time and ultrasonic power on the rate of desulphurization was studied. Tetrachloroethylene Filtrate was consentrated. Analyzing the results of GC-MS and FIIR experiments, the desulphurization mechanism by extraction was discussed.The high sulfur coal was treated in three different oxidants( MnO2 solution, FeCl3 solution, acetic acid and hydrogen peroxide solution)under ultrasonic and microwave radiation. The coals were analyzed by XRD, particle size analyzer and so on. Last, the oxidated desulphurization mechanism was investigated.The conclusions were drawn from experimental rasults:1. Tetrachloroethylene extraction can remove organic sulfur sufficiently, and it is a quite a mild desulphurization technology. It is obvious that the effect of ultrasonic and microwave action on the rate of desulphurization. Routine extraction can remove sulfur in coal under the quite high temperature; The highest temperature is 80 癈 under the ultrasonic field and the heating trait of the microwave, so the quality of desulphurization coal didn't change a lot.2. The rate of desulphurization increase with the ultrasonic time.3. The results of GC-MS and FIIR experments show: tetrachloroethylene extraction can not only remove sulfur in coal but also extract quite a few contained-nitrogen and aromatic compounds.4. The rate of organic and inorganic sulphur removal can be promoted by treated in acetic acid and hydrogen peroxide oxidation under ultrasonic and microwave radiation.5. Comparing the experimental results under single ultrasonic action with the combination ultrasonic and microwave, it is obvious that the action of microwave increases the rate of desulphurization.6. The organic sulphur can be removed by treated in aceticacid and hydrogen peroxide oxidation under microwave radiation and the rate of desulfurizaiton increases with the increasing treatment time.7. Comparing the extraction and oxidization two different systems, the organic sulphur were removed by the two different way, the order was same, from easy to difficult, Wangzhuang >Beijing > Linfen > Yanzhou. The order maybe results from the different sulphur forms in coal.