Study On Co-Pyrolysis,Co-Combustion And Co-Gasification Performance Of High Sodium Tar-Coal Water Slurry

Coal water slurry mixing waste technology as a technology to treat some industrial waste is more effectively.On the one hand,the coal water slurry mixing waste technology is beneficial method to treat waste.On the other hand,it is beneficial to resource reuse.In the process of mixing waste,the performance of the slurry is often affected by different components,because of the variety of industrial wastes,the complex composition leads different effect.The research object is the high sodium tar waste generated in the production process of 1,4 butanediol and coal?ZK coal?in Inner Mongolia mining area.The thermal analysis technology is used to study the co-pyrolysis,co-combustion,co-gasification performance changes of high sodium tar-coal water slurry,and using elemental analyzer,XRD,XRF,SEM-EDX and other analytical instruments to explore the mechanism of performance change and in-depth analysis of the effect of high sodium slag on refractory erosion and its mechanism.The main conclusions are as follows:1)Due to the large loss of most organic components of the tar in the early stage of pyrolysis,the pyrolysis weight loss in some regions is more obvious.The alkali metal Na mainly acts in the late stage of pyrolysis.The presence of alkali metal Na inhibits the aromatization process of the coal char structure.The dehydrogenation polycondensation reaction of continuous graphitization of molecular structure is inhibited by the presence of alkali metal Na,so that the release of small molecules in the secondary degassing is suppressed;2)The large amount of C and H elements in the high sodium tar cause the sample to release more heat during intense combustion;Na⁺in high sodium tar is the main reason for the catalytic effect on combustion.The position containing the alkali metal Na becomes the active center in the combustion process,the sample is more likely to reach the ignition point.The alkali metal Na is uniformly dispersed on the surface and pores of the carbon particles,the combustion is more stable and sufficient.The slurry combustion performance is improved.The incorporation of alkali metal Na causes the sample converts into thomsonite,calcium aluminum silicon eutectic mixture during high temperature,which affects the crystal transformation process during combustion;3)The effect of high sodium tar-CWS gasification performance is consistent with the influence of pyrolysis process and its causes.Due to the action of alkali metal Na,the surface of coal char is rich in more“micropores”and"spots"which are many sodium-containing fine particles on the surface,pores and folds of the coke,while the characteristic areas such as"micropores","spots"and"fine particles"make the coal char shows more intense activity,thereby coal char gasification reactivity is improved;4)More complex changes occur during the molten state of the high-temperature slag containing sodium,which also has a deeper impact on the corundum material.The alkali metal Na in the high temperature slag will reacts with the K and Si elements in the coal ash on the Al₂O₃ to form crystal minerals such as calcium aluminum oxide and nepheline.The albite,anorthite,calcium aluminum feldspar in the slag act on the chromium oxide to form a co-melt,which has a deeper impact on corundum materials and high chromium materials.Figure[76]Table[24]Reference[91]...