I have seen horizontal screw belt, horizontal rake, horizontal double-shaft blade, horizontal shaft with mace, vertical single screw and three-dimensional mixer.
The mixing uniformity can be satisfied, and the highest efficiency should be horizontal ribbon and double-shaft blades.
Huzhou pig feed premix uses a ribbon mixer. They add bacteria to the feed, mix them and ferment them. This mixer performs very well on this wet material, and it can meet the uniformity requirement in about 10 minute.
I have seen a double-shaft paddle continuous feed mixer in Korea, which is more efficient, but it requires higher feeding uniformity and matching output per minute.