1、 The concept and significance of phosphate filling
Phosphate filling is an important technical means in the process of phosphate mining. Backfilling mining technology is a mining method in which selected filling materials (such as tailings, waste rock, etc.) are filled into the goaf in a specific way during ore mining to support the surrounding rock, slow down rock deformation, and prevent surface collapse. In phosphate mining, the backfill mining method can not only achieve efficient mining, but also promote the comprehensive utilization of resources, which has important practical significance and application prospects. For example, it can effectively reduce the storage of waste rock and tailings, reduce environmental pollution, improve resource recovery rate, while ensuring the safety and stability of the mining process, supporting the surrounding rock of goaf, and controlling ground pressure activities.

2、 Phosphate ore filling material
（1） Common filling materials
Tailings: It is a waste material obtained by crushing and grinding ores, with high fluidity and filling ability, which can quickly fill the goaf.
Waste rock: including excavation waste rock, mining waste rock, etc., it has a wide range of sources, low cost, and certain strength and stability.
（2） New filling materials
With the continuous development of technology, new filling materials such as polymer materials and nanomaterials are gradually being applied in phosphate rock filling mining, providing more choices for phosphate mining. In addition, phosphogypsum is also used as a filling material because the processing of phosphate ore produces a large amount of phosphogypsum slag, which not only occupies land but also pollutes the environment. Using phosphogypsum as a filling aggregate to fill the goaf of phosphate mines not only finds a new way to treat phosphogypsum, but also improves the recovery rate of phosphate ore and reduces the impact of mining on the environment.

3、 Phosphate filling system
（1） System composition
The filling system mainly consists of filling stations, pipeline networks, and filling material preparation systems.

Filling station: As the core part of the filling system, it is responsible for transporting filling materials from the preparation system to the mining area.
Pipeline network: It is a bridge connecting the filling station and the mining area, which needs to have sufficient strength and wear resistance to ensure that the filling material can be smoothly transported to the mining area.
Filling material preparation system: responsible for processing raw materials into filling materials that meet the requirements.
（2） Design principles
The design of the filling system should ensure the stability and reliability of the filling material. In the mining process, the filling material needs to withstand various forces such as pressure from the upper rock layers and its own gravity, so the filling material must have sufficient strength and stability.
The design of the filling system should meet the requirements of mining technology. Backfilling mining technology is a special mining method that requires design and optimization based on the characteristics and requirements of the mining process.