To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed.It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and dehydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition solution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the diluted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully applied in Shendong Mines and has great value and wide-spread prospective use.