Method for preparing special fracturing propping agent for shale gas by utilizing low-carbon coal gangue

Abstract

The invention discloses a method for preparing a special fracturing propping agent for shale gas by utilizing low-carbon coal gangue. The method comprises the following steps of: ball milling the low-carbon coal gangue, sieving, taking the sieved coal gangue, placing the sieved coal gangue, coke, silicon micropowder and manganese slags in ball mill, wet grinding, and thus forming a mixed slurry, drying the mixed slurry by adopting a spray drying tower, scattering, taking coal gangue master batches as seeds, pelleting in a sugarcoating machine to form dense balls, forming by coating coke dust, placing the formed particles in a crucible, placing in an electric furnace, sintering at ultralow temperature by adopting a self-spreading manner, naturally cooling, and taking out, thus obtaining the special fracturing propping agent for the shale gas. The method provided by the invention has the advantages of being beneficial for saving high-quantity natural mineral resources, reducing firing temperature, shortening burning period, saving energy sources, and improving the combination property of a product; a secondary balling process is adopted for molding, the self spreading sintering advantage is displayed, the energy consumption is greatly reduced, the operation is convenient and easy to control, and the method is beneficial for industrialized large-scale production; the prepared propping agent has the good characteristics of low density, high intensity, high temperature resistance, high corrosion resistance and the like.

Description

technical field [0001] The invention belongs to the field of new materials, and relates to a method for preparing a proppant, in particular to a method for preparing a special fracturing proppant for shale gas by using low-carbon coal gangue. Background technique [0002] Coal gangue is a kind of dark rock with low carbon content and relatively hard that is associated with coal seams during the coal formation process, and is a rare secondary resource. During the coal mining process, a large amount of coal gangue will inevitably be produced. At present, coal gangue has become the industrial waste with the largest cumulative stock and the most land occupation in my country. Coal gangue is mostly stacked in the open air, which will generate a lot of dust. After being eroded by rainwater, it will produce acidic water and pollute the surrounding water bodies and land. When the coal gangue is stacked unreasonably, it is easy to cause slope instability, leading to the collapse an...

AI Technical Summary

Problems solved by technology

At present, low-carbon coal gangue is mainly used for road construction, grouting materials, backfill materials, production of cement, wall materials and chemical raw materials. Its development and utilization have the characteristics of rough processing, low thermal efficiency, and high energy consumption. Especially In the preparation of sintered materials, the heat loss of ordinary heating methods is as high as more than 50%, and the fuel accounts for more than half of the total production cost

So far, there have been no reports or patents on the development of low-density, high-strength fracturing proppants using low-carbon coal gangue in a self-propagating manner

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