CN-121990799-A - Solid waste salt curing material and preparation method and application thereof

CN121990799ACN 121990799 ACN121990799 ACN 121990799ACN-121990799-A

Abstract

The invention belongs to the field of civil engineering materials, and particularly relates to a solid waste salt curing material, and a preparation method and application thereof. The solidification of the solid waste salt is a harmless treatment process of taking the solid waste salt which is obtained nearby and is typical around a solid waste storage yard and a coastal area as a main material, and adding a solidification substrate into the solid waste salt to fix or contain the solid waste salt in the solidification substrate. The cement mortar comprises, by mass, 63-100 parts of solid waste salt, 30-40 parts of calcium sulfoaluminate cementing material, 63-100 parts of crushed stone, 0.4-0.6 part of coagulant, 0.7-0.9 part of retarder, 0.4-0.6 part of adsorbent, 0.4-0.6 part of water reducer and 9-12 parts of water. According to the invention, an optimal proportioning scheme is selected by adjusting the formula and the performance, and the treated solid waste salt has good mechanical property, leaching resistance, dry and wet resistance and freeze-thawing resistance, so that the self-leveling solid waste salt curing material with stable structure, high strength and low carbon is obtained, and can be widely used for foundation reinforcement, roadbed backfill and mine goaf backfill.

Inventors

SUN SHASHA
ZHANG XIAO
TIAN DONG
WANG TIANQI
ZHOU XUEBIN
MA CHAOQUN
XU HANWEN

Assignees

潍坊水动能科技产业研究院

Dates

Publication Date: 20260508
Application Date: 20241104

Claims (10)

1. The solid waste salt curing material is characterized by comprising, by mass, 63-100 parts of solid waste salt, 30-40 parts of calcium sulfoaluminate cementing material, 63-100 parts of crushed stone, 0.4-0.6 part of coagulant, 0.7-0.9 part of retarder, 0.4-0.6 part of adsorbent, 0.4-0.6 part of water reducer and 9-12 parts of water.
2. The solid waste salt solidifying material according to claim 1, wherein the solid waste salt is solid waste containing inorganic salt as a main component, and the inorganic salt is sodium chloride and sodium sulfate. Pretreatment is carried out before use, and impurities, heavy metals and organic matters in the waste are removed.
3. The pretreatment according to claim 2, wherein the pretreatment is a physical pretreatment for removing impurities and solid particles from the waste salt by physical methods of screening, filtering and precipitation, and the membrane separation pretreatment is a pretreatment for separating impurities and harmful substances from the waste salt by using a membrane separation technique.
4. The solid waste salt solidifying material according to claim 1, wherein the setting accelerator is water glass, the retarder is citric acid, and the adsorbent is activated alumina.
5. The solid waste salt curing material according to claim 1, wherein the crushed stone is composed of, by mass, 50-80 parts of granite crushed stone and 13-20 parts of sand eggs.
6. The solid waste salt solidified material of claim 5, wherein the granite broken stone has a particle size of 10-50 mm, and the sand egg has a particle size of 20-30 mm.
7. And adding 9-12 parts of water. Too little water can not ensure the sufficient hydration of cement, too much water can cause bleeding phenomenon.
8. A method for producing a solid waste salt solidified material according to any one of claims 1 to 7, comprising the steps of: (1) Crushing the solid waste salt, stirring and mixing the crushed solid waste salt with calcium sulfoaluminate cementing material and crushed stone, adding a coagulant, a retarder, an adsorbent and a water reducing agent, stirring and mixing, adding water and stirring to prepare slurry; (2) And (3) injecting the slurry into a mould, and curing at 23+/-1 ℃ and humidity of 99% to prepare the solid waste salt curing material.
9. The method for preparing solid waste salt solidified material of claim 8, wherein the powder which can pass through a 80-mesh sieve after crushing the solid waste salt is stirred and mixed with calcium sulfoaluminate cement and crushed stone.
10. The use of a solid waste salt solidified material according to any one of claims 1-7, characterized in that after solid waste salt is selected in the depth range of 0-1.8m, the original ground is crushed and leveled after the solid waste salt is removed, the selected solid waste salt is crushed and mixed with calcium sulfoaluminate cementing material and crushed stone, a coagulant, a retarder, an adsorbent and a water reducing agent are added and mixed, water is added and mixed to prepare a slurry, and the slurry is quickly layered and backfilled to the crushed and leveled original ground.

Description

Solid waste salt curing material and preparation method and application thereof The invention relates to a solid waste salt curing material, a preparation method and application thereof, belonging to the field of civil engineering materials. Background Along with the rapid development of the domestic chemical industry, a large amount of waste salt is generated in the production process, and the solid waste salt comprises byproduct salt and high-salt residues generated in the chemical production process and also comprises evaporative crystallization salt generated in the high-salt wastewater treatment process. In the present situation, these solid waste salts cannot be directly used as industrial raw materials, and can only be stored or handled outside, which not only occupies a large amount of land, but also has a treatment cost of more than 3000 yuan/ton, which is an unacceptable problem for enterprises. On the other hand, the disposal rate and the recycling rate of the waste salt are extremely low due to the fact that the domestic waste salt disposal technology and related standards are reliable, and most of the waste salt is mainly buried in a rigid way. This situation not only poses a threat to the environment, but also causes waste of resources. Therefore, the development and reuse of solid waste salts has become a hotspot problem. From the aspects of the national hazardous waste policy requirements and the development of the hazardous waste disposal industry, the treatment of the solid waste salt is necessarily developed towards the comprehensive utilization direction of resources. The waste salt often contains a large amount of organic matters and heavy metals, and the existence of the impurities is harmful to the environment and increases the difficulty of recycling. There is a need to develop efficient, low cost removal techniques to ensure the safety and economics of waste salt recycling. However, each link requires a great deal of manpower, material resources and financial resources. In addition, although the industrial waste salt recycling has great potential, the related policies and regulations are not perfect at present, the definite waste salt treatment standard and emission standard are lacked, and corresponding policy support and encouraging measures are lacked, which limits the development of waste salt recycling. There is a need to enhance policy research and regulation formulation to promote sustainable development of industrial waste salt resource utilization. The utilization technology of industrial waste salt resource mainly comprises the technologies of incineration, high-temperature hot melting, organic carbonization pyrolysis, advanced oxidation, wet catalytic oxidation and hydrothermal oxidation. After technical treatment, the harmless and resource utilization of the waste salt is realized. These techniques have achieved some success in practical applications, but still present some challenges and limitations. There is a need to strengthen research and development of low-cost, efficient and environment-friendly industrial waste salt recycling technology, and to establish perfect policy and regulation system to promote the recycling of industrial waste salt and environmental protection. In summary, in order to solve the problems of low efficiency, high cost, incapability of realizing the maximum utilization of resources and the like of the novel treatment technology, solid waste salt in coastal areas is sampled, and the solid waste salt is used as aggregate to research the laws of physical and chemical changes of the solid waste salt in different ages and different doping amounts, so that the solid waste salt curing method is provided, and the self-leveling solid waste salt curing material which is stable in structure, long-term in prevention and treatment effect, high in strength and green and low in carbon is obtained. The method can be widely applied to foundation reinforcement, highway and railway roadbed, trench backfill and mine goaf backfill. Disclosure of Invention In order to comprehensively utilize the solid waste salt, the preparation method of the solid waste salt curing material provided by the application takes the solid waste salt, calcium sulfoaluminate cementing material and crushed stone as main materials, takes the coagulant, the retarder, the adsorbent and the water reducing agent as secondary materials, adds a certain proportion of water, and then stirs the materials to form the building material which has fluidity, has a certain strength and long-term stability after hardening, thereby reducing the pollution of the solid waste salt and providing raw materials for the building industry. The relationship between the fracture and compression strength and durability of the cured waste salt, the impermeability and the doping amount and age of each material is researched, so that a basis is provided for the design and construction of roadbeds in solid waste salt ar