According to the bad performance of traditional PID controller in big time-delay and model-free system, for keeping the residual moisture content and the thickness on the material conveyor of vacuum-pyroair dehydrated nitrocellulose in a reasonable range, then suggest to introduce multiple-value logic control algorithm in head tank discharge flux control. Introduce the description of multiple-value logic control arithmetic and the system structure, and put it in the trial run. Practice shows that this controller meets the performance requirement in manufacture, and the multiple-value control arithmetic is superior to PID in robust stability, overshoot and response time, and it is applied to promote in the field of industrial control.