Novel environment-friendly phosphogypsum-based impermeable material

Abstract

The invention discloses a novel environment-friendly phosphogypsum-based impermeable material. The impermeable material is obtained by mixing raw materials by stirring, paving and rolling, wherein theraw materials include 70-90% of phosphogypsum, 5-10% of bentonite, 0.1-1% of a polymer and 10-20% of water by mass. The impermeable material uses the phosphogypsum as a main material, so that the problem of comprehensive utilization of the phosphogypsum is solved; the impermeable material is easy to prepare and low in cost; the impermeable material has the characteristic of extremely low permeability, the impermeable material with the thickness of 70-90mm can replace an impermeable clay layer with the thickness up to 5m, and the impermeable material has strong self-repairing ability; the impermeable material has high flexibility, so that the impermeable material can resist nonuniform settlement; the impermeable material is prevented from being washed away through formation of a gel; the impermeable material has high physical and chemical stability; the impermeable material has strong water retention capacity, so that the impermeable material is resistant to dry cracking; the impermeable material can be seamlessly jointed with various structures (pipes, concrete columns, steel pipes and the like); the impermeable material has a high friction angle and strong cohesion, so that the impermeable material can be applied to various side slopes of which the slope can reach 1:1; the impermeable material is easy to lay and low in rolling requirement; the impermeable material is small infilling volume; the impermeable material is good in durability and long in service life.

Description

technical field [0001] The invention relates to the technical field of anti-seepage materials, in particular to a novel environmentally friendly anti-seepage material based on phosphogypsum. Background technique [0002] At present, anti-seepage technology has been widely used in industrial and civil structures such as industrial slag storage, heavy metal tailings storage, industrial factories, tank farms, polluted sites, rivers and ponds, reservoirs and dams, providing groundwater, air and soil. Reliable long-term protection. [0003] The anti-seepage materials mainly include natural clay and HDPE anti-seepage membrane. However, most clays do not meet the requirements of national standards in terms of permeability coefficient (less than 10-7cm / s) and compaction (>95%). In addition, natural clay linings often have cracks due to uneven settlement or drying , significantly weakening its anti-seepage effect. Although the HDPE anti-seepage membrane has good anti-seepage pe...

AI Technical Summary

Problems solved by technology

However, most clays do not meet the requirements of national standards in terms of permeability coefficient (less than 10-7cm / s) and compaction (>95%). In addition, natural clay linings often have cracks due to uneven settlement or drying , which significantly weakens its anti-seepage effect

Although the HDPE anti-seepage membrane has good anti-seepage performance, it also has obvious disadvantages: a. The thickness is relatively thin, generally 1.0-2.0mm, and its puncture resistance is very low, so it has very high requirements for the foundation cushion. Blocks, hard objects and tree roots may pierce the anti-seepage membrane; b. Due to the small friction angle and weak cohesion of the general HDPE anti-seepage membrane foundation cushion material, the slope of the anti-seepage slope is generally required to be lower than 1: 2. Many engineering sites have steep slopes, and slope cutting works are required. The amount of work is large and the cost is high; c. HDPE anti-seepage membranes generally use welding technology, but welding is difficult at the joints between anti-seepage membranes, pipelines, and concrete structures, and external force It is easy to tear under the action, and eventually destroy the overall anti-seepage effect

The anti-seepage material of this invention patent is mainly aimed at the anti-seepage of polluted sites. The amount of bentonite and polymer is large, and the relative cost of anti-seepage is high, so it is difficult to promote in practice.