Double-line coal blending method for preventing coke strength from deterioration

The invention relates to a double-line coal blending method for preventing coke strength from deterioration. The method comprises the following steps: designing the main proportion according to the mine pit coal quality characteristics and coke quality control target, and dividing the main proportion into two sub-proportions according to the binding property and cokeability of each type of coal in the main proportion, wherein the two types of blended coal in the two sub-proportions have identical to similar binding property and cokeability; and pulverizing and uniformly mixing. The method does not need technical modification or capital investment increase, and is risk-free for use. After the original double-line blended coal manufacturer adopts the method, the coke crushing strength can be enhanced by 0.4-2.0%, the abrasion strength can be lowered by 0.2-1.0%, and the coke strength stability is enhanced; and the improvement degree is related to the original double-line blended coal quality difference and coal