Dry-mixed mortar compound mineral powder plasticizer and preparing method and application thereof

The invention discloses dry-mixed mortar compound mineral powder plasticizer and a preparing method and application thereof. The plasticizer is prepared from, by weight, 3-10 parts of sodium silicate, 1-5 parts of ammonium polyphosphate, 14-22 parts of compound slag, 5-12 parts of pyroligneous, 7-15 parts of sodium tannate and 18-26 parts of phenolic resin, and the compound slag is prepared from, by weight, 4-8 parts of manganous slag and 10-14 parts of phosphorus slag. The preparing method includes the steps that phenolic resin is smashed and mixed with a sodium tannate solution, the mixed solution is heated and stirred, then a wood vinegar solution is added, and a mixed solution A is obtained after heating and stirring; ammonium polyphosphate and compound slag are mixed and ground, sodium silicate is added, the mixture continues to be ground, the mixed solution A is added, and the plasticizer is obtained after heating, ultrasonic treatment and stirring. The prepared plasticizer is used in dry-mixed mortar,