Xinhai Zimbabwe 700tpd gold concentrator project is one of the turnkey solution for mineral processing plant of Xinhai. In grinding process, considered multiple factors, Xinhai decided broken qualified products in fine bin will be transported into the two-stage closed circuit grinding and classification system. Between ball mill discharge and a closed-circuit classifying, add a jig re-election system. After Jig one roughing, twice shacking table cleaning, gold placer will be produced. Therefore, it is no doubt that wet energy-saving rod mill is the ideal choice of grinding equipment.The steel rod takes regular movement in mill, the grinding particle size is even, which reduces overgrinding greatly. In gravity separation, the rod ball is grinding ore with the whole steel rod rather than a point of steel rod. The cap curvature of conical end is little small, making the steel rod move regularly, so its applied force is very even. Before the coarse grain is grinded, the fine grain is seldom grinded, which pretending the gold ore overgrinding in coarse grinding process, so the gold particle size is even with high quality of discharge ore.Large diameter of hollow shaft, fast discharge speed. The diameter of hollow shaft is large, which is easy to maintain; and it can reduce the pulp level, discharge fast.Suit to coarse grinding process, large capacity. Wet energy-saving rod mill is often used to the coarse grinding of first opening grinding stage, the product particle size is 3-1mm, the capacity is larger than the same standard ball mill, which is beneficial to improve the discharge rate, make the mineral processing finish in the established time.This project mainly adopted CIL process, considering the gold grade of raw ore is up to 6g/t, Xinahi added gravity separation process in grinding and classification circuit to recycle gold particle early and avoid the loss of gold particle in leaching system, which guarantees the ideal gold recovery rate.Xinhai provided the turkey solutions for mineral processing plant. With the scientific and rigovous attitude and the focus on each construction details, Xinhai provided fine design and construction, especially in grinding process, and made reasonable arrangement and implementation for each equipment installation and commissioning, the customer is very satisfied with the result.