Where is mine waste rock and tailings used?

In recent years, in order to eliminate the impact of waste rock and tailings produced by mining on people's production, the state has introduced a series of policy measures, which have made certain achievements at the same time, and put forward higher requirements for the next development. Gou Hailong said that in the next step, enterprises should stand on the understanding that tailings are an "economical and practical composite mineral raw materials that can be used as a whole", and carry out technical research and product development. Actively cooperate with scientific research institutions engaged in the comprehensive utilization of tailings technology research, product development and results transformation, and organize personnel to implement the comprehensive utilization of tailings projects according to the mine's own situation and market factors. It is suggested that under the background of "double carbon", special funds for green mine construction should be set up to provide financial support for the sustainable development of green mines. Improve the green mine construction management system, set up a special technology research and development team, combined with the actual situation of the mine to implement. Actively introduce low-carbon environmental protection technology and equipment, or through technological improvement, resource integration to achieve low energy consumption and low pollution.

There are challenges to achieving the goals

The industry and enterprises are currently facing huge challenges, and it is suggested that the government departments can carry out classified policies and hierarchical control on the mining and comprehensive utilization of resources in accordance with the principle of "scientific pollution control, accurate pollution control and legal pollution control". Simplify the procedures of project approval and EIA approval, and improve the efficiency of project approval; Give tax relief policies to reduce the burden on enterprises; We will study and formulate special incentive policies for awards and subsidies to arouse the enthusiasm of enterprises.

Recently, the "Implementation Plan on Accelerating the Comprehensive Utilization of Industrial Resources" jointly issued by the Ministry of Industry and Information Technology, the National Development and Reform Commission, the Ministry of Science and Technology and other eight departments clearly put forward that by 2025, the comprehensive utilization rate of bulk industrial solid waste will reach 57%. In order to achieve this goal, the industry and enterprises are currently facing huge challenges.

"The current challenges are mainly: First, the increase in regional production capacity and fierce product competition. Taking Hebei as an example, the comprehensive utilization of resources in Tangshan is rich in products, the northeast regional maritime market is developing strongly, and Hebei Province has laid out large sand and stone production bases in Shijiazhuang, Qinglong and other places, and the homogeneous competition is becoming more and more fierce. Second, environmental control has become stricter, and the construction and operation of production lines have become more difficult. Third, Hebei levied resource tax on sand and stone according to the quantity, and the tax on building materials products has increased." In this regard, Huang Jiaqiang suggested that the focus should be on increasing policy support from the following aspects: First, it is recommended that government departments should be able to classify and control the mining and resource comprehensive utilization industries according to the principle of "scientific pollution control, accurate pollution control and legal pollution control". Second, simplify the procedures of project approval and EIA approval to improve the efficiency of project approval. The third is to give tax relief policies to reduce the burden on enterprises. The fourth is to study and formulate special incentive policies for awards and subsidies to mobilize the enthusiasm of enterprises.

"The quality of crushed stone and machine-made sand has a significant impact on the quality of concrete. If the quality of crushed stone and machine-made sand is substandard, the quality of concrete will be substandard." Zhang Shuangcheng said that the ideal grain shape of gravel and machine-made sand should be approximately circular surface with a certain number of shallow small concave points of particles. This kind of granular gravel and machine-made sand particles are then composed into a good grading, so that in concrete, the interface bonding force between the gravel and machine-made sand is the best, the void ratio is the lowest, the fracture capacity is the highest, the center distance between the aggregates is the closest, and the specific surface area of the aggregates is the smallest. It is suggested that the waste iron ore is used to refine the gravel and machine-made sand to prepare solid waste low-carbon high-quality concrete. This should be the direction of healthy development of concrete.