Micro-crosslinking emulsion wall-fixing agent based on lithium silicate-ultrafine particles and preparation method of micro-crosslinking emulsion wall-fixing agent

The invention relates to a chemical wall-fixing agent for an anti-sloughing drilling fluid for a shale stratum in petroleum drilling, in particular to a micro-crosslinking emulsion wall-fixing agent based on lithium silicate-superfine particles and a preparation method of the micro-crosslinking emulsion wall-fixing agent. The micro-crosslinking emulsion wall-fixing agent comprises the following components: lithium silicate, ultrafine particles, a stabilizing agent, a dispersing agent, a cross-linking agent and the balance of water. The preparation method comprises the following steps: emulsifying and dispersing or dissolving the stabilizer in water, adding the blocking material, mixing and concentrating, and adding the lithium silicate aqueous solution for mixing; and finally, carrying out micro-crosslinking, adding a quantitative crosslinking agent under the condition of stirring at room temperature, properly supplementing water, and ensuring the flowability of the system to form a final product. As an envir