Impurity removing equipment for grain processing

The invention discloses impurity removing equipment for grain processing. The equipment comprises a vibration box; a vibration cavity is formed in the vibration box; a dust removing device for removing dust by using air currents is arranged on the left side of the vibration box; a vibration device is arranged in the vibration cavity; a screening box is fixedly connected to the lower side end surface of the vibration box; a screening cavity communicating with the dust removing device is arranged in the screening box; a screening device is arranged in the screening cavity; and the screening device uses rotary vibration for removing impurities larger than grain particles. A primary vibration screening device can quickly adjust the length of a crank in a crank slide block mechanism through rotation of a knob, so that the vibration amplitude adjusting function is achieved, operators conveniently adjust the vibration amplitude, the impurity removing adaption to different grains is improved,the impurity removing eff