Preparation method of core-shell ceramsite fracturing propping agent for oil and gas collection

Abstract

The invention relates to a preparation method of a core-shell type ceramsite fracturing propping agent for oil and gas collection, which comprises the following steps: (1) grinding municipal sludge containing organic matters into powder, and then granulating and drying to obtain a core precursor; (2) uniformly mixing clay and scrap iron powder, then adding water, and uniformly stirring, so as to obtain inner coating layer slurry; and (3) mixing clay and water, and uniformly stirring to obtain the outer coating layer slurry. And (4) immersing the inner core precursor into inner coating layer slurry to uniformly coat the outer surface of the inner core precursor, then taking out the inner core precursor, drying, then immersing the obtained particles into outer coating layer slurry again to uniformly coat the outer surface of the inner core precursor, then taking out the particles, drying, uniformly placing the particles, and then calcining to obtain the composite material. The ceramsite fracturing propping agent is obtained after completion. The core-shell type fracturing propping agent disclosed by the invention is low in density and has good compression resistance, and the purposes of reducing the density of the fracturing propping agent and keeping the good compression resistance of the fracturing propping agent are achieved.

Description

technical field [0001] The invention relates to the technical field of fracturing proppants, in particular to a preparation method of a core-shell type ceramsite fracturing proppant used for oil and gas collection. Background technique [0002] Fracturing proppant is mainly used in deep wells and fracturing reconstruction of high-pressure oil and gas layers. The fracturing proppant is driven into the cracks of the fractured rock formation through high-pressure carrier fluid, and plays a role in supporting the cracks from closing due to stress release, thereby maintaining High conductivity, make the oil and gas unimpeded, increase production. Practice has proved that fracturing with the addition of fracturing proppant can increase production by more than 30%, effectively improving the efficiency of oil and gas collection. [0003] The main raw material of traditional fracturing proppant is bauxite, which is crushed and finely ground into fine powder and then sintered at high...

AI Technical Summary

Problems solved by technology

[0003] The main raw material of traditional fracturing proppant is bauxite, which is crushed and finely ground into fine powder and then sintered at high temperature after compounding with additives. After sintering, the main crystal phase is usually corundum phase, which has a high density, resulting in the The density is high, which affects the subsequent use of the carrier fluid to carry it into the rock formation

However, the density of the fracturing proppant should not be too low, otherwise the compressive strength of the fracturing proppant cannot meet the demand

[0004] In order to overcome the above-mentioned problems, some studies have achieved certain results by using composite materials to prepare low-density fracturing proppants, but these technologies generally have problems such as complex processes, high raw material costs, and unsuitability for large-scale production. More importantly, it did not reduce the density of the fracturing proppant while maintaining its good compression resistance, resulting in poor overall performance of the fracturing proppant