For walnut shell grinding at pilot scale, the most suitable solution is usually a colloid mill or a high-intensity grinding unit, depending on the required final particle size. Since walnut shells are a hard fibrous material, the key factor is whether you need coarse crushing or fine powder.
For this kind of application, a GlobeCore CLM colloid mill can be considered if fine grinding and uniform output are required. If stronger impact treatment or activation of the material is needed, an AVS vortex layer unit may also be suitable as part of the process line.
In practice, for a capacity of around 15 kg/h, a pilot configuration based on CLM equipment would be a logical starting point, especially for testing grinding efficiency and final particle size before scaling up.