Preparation And Properties Of Coal Mine Fire Prevention And Control Biomass Hydrogel

Coal spontaneous combustion is one of the main disasters affecting the safety production of underground coal mines,but the technology and materials for preventing and controlling coal spontaneous combustion have some shortcomings while playing their role.At home and abroad in recent years,with the research and development of fire extinguishing fire retardant material,have to adapt the traditional material development to have a wider range of polymer materials and formation water gel with high water absorbability,high water retention characteristics,sets of solid,such as water,oxygen insulation,cooling and plugging into an organic whole,to be able to avoid the traditional material aging,solid water is poor and poor thermal stability.In this paper,the preparation and properties of mineral biomass hydrogel were studied,and the main achievements were as follows:Using chemical crosslinking method,using carboxymethyl cellulose and polyvinyl alcohol as matrix,epichlorohydrin as crosslinking agent and lignin as"extended crosslinking agent",mineral biomass hydrogel was successfully prepared under alkaline condition.The hydrogel has the characteristics of high swelling,high water retention and good thermal stability.It was found that the mass concentration of raw materials had a certain effect on the performance of hydrogels.The morphology of hydrogels was analyzed by scanning electron microscopy.The results showed that hydrogels contained a large number of holes and lamellar structures,and this excellent three-dimensional network structure enabled hydrogels to absorb a large amount of water and store it.Considering the swelling rate,yield and water retention rate of hydrogels,three hydrogels with the best performance,L_4.2C_6.7P_2.1,L_4.2C_6.2P_3.7 and L_3.2c_6.7P_3.7,were selected.Further analysis was conducted on the water retention performance of hydrogels under heating condition,and it was found that when the temperature was 160℃,The water retention rate of L_4.2C_6.2P_3.7 hydrogel is still 26.54%,indicating that the gel network structure can bind the internal water,making the water escape and evaporation more difficult.By studying the swelling property of hydrogel,it is found that the hydrogel belongs to the second order swelling mechanism.Based on the rheological test analysis,compared with CP gels without AL,the elasticity of L_4.2C_6.7P_2.1,L_4.2C_6.2P_3.7 and L_3.2C_6.7P_3.7 hydrogels is greatly improved,thus realizing the long-term plugging of coal seam fractures.Hydrogel belongs to pseudoplastic fluid,and its shear thinning property is beneficial to the transportation and flow of hydrogel in the pipeline,as well as the accumulation and sealing in the fire prevention area.Based on thermal stability analysis,the carbon residue of L_4.2C_6.2P_3.7at 600℃was as high as 49.09%.The introduction of AL improved the network structure of hydrogel and increased the thermal stability of hydrogel.The best hydrogel performance was determined as L_4.2C_6.2P_3.7.Through temperature programmed experiment and FTIR experimental study,it is found that L_4.2C_6.2P_3.7 hydrogel can significantly reduce the coal oxygen consumption rate,CO and CO₂ production rate and increase the activation energy compared with traditional Ca Cl₂ and CP inhibiting materials,and has the best inhibiting effect on raw coal samples.The types of functional groups of the coal after hindrance remain unchanged,and the number of active functional groups of the coal decreases significantly.From the microscopic point of view,the double inhibition effect of L_4.2C_6.2P_3.7 hydrogel on coal hindrance is further confirmed,which can better inhibit the oxidation of coal and prevent the occurrence of coal spontaneous combustion.Figure[66]Table[17]Reference[98]...