Technical Overview
Composite gel (high water-retention hydrogel) (MAG-Ⅰ) is a grouting-enhanced fire prevention and extinguishing material. When used in combination with yellow mud slurry and fly ash slurry, it can significantly increase the slurry concentration, reduce the risk of pipeline blockages and bursts, improve grouting efficiency and quality, largely avoid the phenomenon of channeling during single grouting, enhance the filling effect, prolong the retention time of water in the goaf, and at the same time reduce the unit grouting cost.

Technical Characteristics
(1) High solid-to-liquid ratio: The maximum solid-to-liquid mass ratio can reach 1.5, which is 7 times that of pure yellow mud slurry, significantly improving grouting efficiency.
(2) Large water-holding capacity: The water retention rate of yellow mud slurry sediment exceeds 50%, providing better cooling performance compared with pure yellow mud slurry.
(3) Excellent water retention: It forms a hydrogel through normal chelation and adheres to loess, enabling long-term water retention in the goaf and significantly extending the effective period of the slurry.
(4) Good thermal stability: The sediment formed by the hydrogel and loess has high solid content and good adhesion, offering better filling performance compared with pure yellow mud slurry.
(5) Excellent filling and plugging effect: The sediment formed by the hydrogel and loess has high solid content and good adhesion, providing better filling performance compared with pure yellow mud slurry.
(6) High safety: The mixing and reaction process with water generates no heat. The hydrogel fibers consolidate and adsorb to the loess, and in case of high temperature or open flame, there is no sudden gasification, eliminating the risk of water-gas explosion.
(7) Safe and environmentally friendly: Non-toxic and non-corrosive.

Performance Experiments
Figure 1:200g of water mixed with 200g of soil and left to stand for 30 seconds.
Figure 2: 20g of water mixed with 200g of soil，followed by the addition of composite colloid（high water-retention hydrogel）（MAG-Ⅰ）fire prevention and extinguishing material.
Figure 3: After the solution from Figure 2 was left to stand for 30 minutes, the losses settled and water separated out in the upper layer.
Figure 4: After pouring out the upper layer of water from the beaker shown in Figure 3, the beaker was inverted on the table to show the sedimentation effect of the yellow mud slurry.

Application Location
(1) Prevention and control of coal spontaneous combustion in underground coal mine goafs,behind working face supports, and near open-off cuts and stop lines.
(2) Prevention and control of coal spontaneous combustion in locations such as roadway sides, roadway roofs, and goafs adjacent to gob-side entries.
(3) Prevention and control of local spontaneous combustion areas in open-pit coal mines.
(4) Prevention and control of local spontaneous combustion areas in coal gangue piles.

Application Process
The composite gel is mixed with fly ash slurry or yellow mud slurry in a specific ratio, then pumped through dedicated equipment into the grouting pipeline, and injected into the goaf or fire zone via the pipeline.