Portland cement raw material mixing device and mixing process

The invention discloses a raw material mixing device and process for Portland cement, and belongs to the technical field of cement mixing equipment. A raw material mixing device for Portland cement comprises a first stirring tank, a second stirring tank and a feeding pipe communicated with the top of the first stirring tank, and the bottom of the feeding pipe is rotationally connected with a rotating pipe located in the first stirring tank; the blanking pipe is used for receiving the raw materials fed by the feeding pipe, vent holes are formed in the top wall of the blanking pipe, a fan is arranged in the blanking pipe, the rotating pipe extends into the blanking pipe, a filter screen is fixedly arranged between the blanking pipe and the inner wall of the first stirring tank, and an exhaust outlet is formed in the side wall of the first stirring tank; the material distributing mechanism is arranged in the material falling pipe and is used for uniformly distributing the raw materials fed by the material feedin