2025

Haiwang's high-efficiency sand washing technology and equipment are once again included in the "Catalog of Advanced and Applicable Technologies for the Conservation and Comprehensive Utilization of Mineral Resources (2025 Edition)"

Author:

Recently, the Ministry of Natural Resources publicly released the "Catalog of Advanced and Applicable Technologies for the Conservation and Comprehensive Utilization of Mineral Resources (2025 Edition)". Weihai Haiwang Technology Co., Ltd.'s independently developed "High-Efficiency Sand Washing, Fine Sand Recovery Process and Integrated Equipment Technology" was successfully selected and included as one of the high-efficiency mineral processing technologies. This marks the second time that Haiwang's sand processing technology has received authoritative recognition from the Ministry of Natural Resources, following its initial inclusion in 2022.

Technological Value and Application Background

Currently, my country has accumulated over 70 billion tons of mine tailings and waste rock, resulting in both resource waste and environmental risks. At the same time, the annual consumption of sand and aggregate in China reaches 16-18 billion tons, highlighting the significant potential for the resource utilization of mine tailings. Transforming mine tailings into construction sand and aggregate, achieving a shift from "environmental burden" to "urban mine," is an effective way to cultivate green industries, mitigate environmental risks, and contribute to the "dual carbon" goals. However, mine tailings often have an unreasonable particle size distribution and a high proportion of fine particles, making it difficult for conventional sand washing processes to meet the grading requirements for construction sand. Therefore, there is an urgent need to develop a "multi-stage sand selection technology for complex raw materials" to address the challenges of utilizing these complex raw materials.

Haiwang Company, combining high-precision bucket wheel sand washers, countercurrent sand washers, and high-efficiency cyclone screening equipment, has developed a multi-stage sand separation process targeting the characteristics of tailings sand, such as discontinuous particle size distribution and a high proportion of fine particles. This process includes stages such as coarse particle separation (5 or 3 mm), coarse sand washing (1-5 or 3 mm), fine sand washing (1-0.075 mm), and de-sludging (less than 0.075 mm), achieving the goal of "removing coarse particles, removing fine particles, separating intermediate sizes, and customizing according to needs," thereby improving the comprehensive utilization efficiency of tailings.

Three Major Innovations:

Pioneering the multi-stage sand selection and separation process

Utilizing a process of "coarse particle separation + coarse sand wheel washing + fine sand countercurrent washing + hydrocyclone desliming," the complex raw materials are separated and sorted according to particle size, and then blended according to the required particle size distribution of the finished sand, achieving high value-added utilization of complex raw materials.

A double-groove dynamic and static zone bucket wheel sand washing machine has been developed.

It solves the problems of short-circuiting of feed material and sand loss caused by turbulent flow in traditional bucket wheel sand washing machines, improving the recovery efficiency of coarse sand, with a coarse sand recovery rate of up to 95%. At the same time, it innovatively adopts a U-shaped curved screen structure to improve product cleanliness, resulting in a finished sand with a clay content of less than 3%.

A high-precision countercurrent sand washing machine has been developed.

Utilizing the principle of hindered settling and classification, the sand washing equipment classifies particles based on their settling velocity differences through an upward flow. Innovative structures such as a low-turbulence swirling inlet well and an inclined plate flow-blocking device reduce the impact of turbulence at the inlet and outlet on sedimentation within the washing tank, thereby improving classification accuracy. This allows for achieving a finished fine sand product with a clay content of less than 3% while maintaining a +0.074 mm recovery rate of over 95%.