阅读说明：本技术 新型微生物矿化碳酸盐胶凝材料加固钙质砂土和沙漠沙的方法 (Method for reinforcing calcareous sandy soil and desert sand by using novel microorganism mineralized carbonate cementing material ) 是由 王军 於孝牛 符洪涛 王哲 王鹏 袁国辉 倪俊峰 高紫阳 叶强 杨克军 金锦强 于 2019-08-14 设计创作，主要内容包括：本发明公开一种新型微生物矿化碳酸盐胶凝材料加固钙质砂土和沙漠沙的方法,包括消石灰或硝酸钙质量占比1、固碳菌质量占比2、泡沫二氧化碳质量占比1、钙质砂土和/或沙漠沙质量占比为10,混合反应形成生物碳酸盐水泥,待反应结束后凝固。(The invention discloses a method for reinforcing calcareous sandy soil and desert sand by using a novel microbial mineralized carbonate cementing material, which comprises the steps of mixing and reacting slaked lime or calcium nitrate in a mass ratio of 1, carbon fixing bacteria in a mass ratio of 2, foamed carbon dioxide in a mass ratio of 1 and calcareous sandy soil and/or desert sand in a mass ratio of 10 to form biological carbonate cement, and solidifying after the reaction is finished.)

1. A method for reinforcing calcareous sandy soil and desert sand by using a novel microbial mineralized carbonate cementing material is characterized by comprising the following steps of: the method comprises the steps of mixing and reacting lime hydrate or calcium nitrate in a mass ratio of 1, carbon-fixing bacteria in a mass ratio of 2 and foamed carbon dioxide in a mass ratio of 1 and calcareous sandy soil and/or desert sand in a mass ratio of 10 to form biological carbonate cement, and solidifying after the reaction is finished.

2. The method for reinforcing calcareous sandy soil and desert sand by using the novel microbial mineralized carbonate cementing material as claimed in claim 1, which is characterized in that: mixing slaked lime in the mass ratio of 1, streptomyces microflavus in the mass ratio of 2, foamed carbon dioxide in the mass ratio of 1 and calcareous sandy soil in the mass ratio of 10, reacting after mixing to form biological carbonate cement, and solidifying after the reaction is finished.

3. The method for reinforcing calcareous sandy soil and desert sand by using the novel microbial mineralized carbonate cementing material as claimed in claim 1, which is characterized in that: and preparing a mixed solution from 1 mass percent of calcium nitrate, 2 mass percent of streptomyces microflavus and 1 mass percent of foamed carbon dioxide, spraying the mixed solution on desert sand, reacting on the surface of the desert sand to form biological carbonate cement, and solidifying after the reaction is finished.

4. The method for reinforcing calcareous sandy soil and desert sand by using the novel microbial mineralized carbonate gelled material as claimed in claim 2, wherein the method comprises the following steps: a drill pipe and a spiral stirring rod are arranged, a mixed liquid conveying channel is arranged in the spiral stirring rod, a liquid discharging hole is formed in the side surface of the lower part of the spiral stirring rod, the upper end of the spiral stirring rod is connected with a pumping mechanism, and a pipeline of the pumping mechanism is communicated with the mixed liquid conveying channel; when in operation, firstly, a pile machine is adopted to drill a drill pipe into the calcareous sandy soil; installing a bolt stirring rod on a pile machine, operating the pile machine to spirally stir the spiral stirring rod from the upper end of the drill pipe to gradually enter the bottom of the drill pipe, gradually entering the drill pipe by the spiral stirring rod, inputting the mixed solution into the drill pipe by the pumping mechanism and standing for more than 24 hours; then lifting the drill pipe upwards; the operation is circularly carried out on the calcareous sandy soil ground one by one, so that sandy soil columns formed by the consolidation of the calcareous sandy soil are densely distributed in the calcareous sandy soil ground, and the calcareous sandy soil is reinforced.

Technical Field

The invention relates to a method for reinforcing calcareous sandy soil and desert sand by using a novel microbial mineralized carbonate cementing material.

Background

In the water and soil control, the sand and dust control and the reinforcement of calcareous sandy soil are two important points all the time, the existing control method adopts the method of planting trees and grass to solidify sandy soil, but the time period of the method is too long, and the method also adopts industrial cement to directly reinforce calcareous sandy soil, but a solidified layer formed by the method has obvious traces of the industrial cement, is difficult to be integrated with the surrounding environment, and can cause pollution to the surrounding environment.

Disclosure of Invention

The invention aims to solve the technical problem of providing a method for reinforcing calcareous sandy soil and desert sand by using a novel microbial mineralized carbonate cementing material which can form a solidified layer on the calcareous sandy soil and the desert sand more environmentally friendly and quickly.

Therefore, the method for reinforcing calcareous sandy soil and desert sand by using the novel microbial mineralized carbonate cementing material comprises the steps of mixing and reacting slaked lime or calcium nitrate in a mass ratio of 1, carbon fixing bacteria in a mass ratio of 2, foamed carbon dioxide in a mass ratio of 1 and calcareous sandy soil and/or desert sand in a mass ratio of 10 to form biological carbonate cement, and solidifying after the reaction is finished.

The invention has the technical effects that: the slaked lime or the calcium nitrate contacts with the water solution to form a calcium hydroxide solution or a calcium nitrate solution, the microorganisms are used for converting carbon dioxide into carbonate, the carbonate reacts with the calcium hydroxide solution or the calcium nitrate solution to generate a biological calcium carbonate cementing material, and loose calcium-fixing sandy soil and desert sand are consolidated and have certain mechanical properties, such as: the hardness test of the desert sand obtained by reinforcement by adopting the method is 10, which is generally between 8 and 12, the compressive strength of the calcareous sandy soil can reach 2 MPa, the hardness and the compressive strength of the calcareous sandy soil both reach higher levels, a cured layer can be quickly formed, the curing efficiency is higher, and the time is shorter. The invention mainly adopts the carbon-fixing bacteria such as streptomyces microflavus and the like to solidify and react to form the biological carbonate cement, so the invention is more environment-friendly, and the traces such as the surface color and the like after solidification have little difference with the surrounding environment, and is particularly suitable for reinforcing mountains in scenic spots and parks and the like.

Drawings

FIG. 1 is a particle size distribution diagram of calcareous sands.

FIG. 2 is a scanning electron micrograph of calcareous sand.

Figure 3 is an XRD pattern of calcareous sand.

Figure 4 is an XRD pattern of soil.

FIG. 5 is a diagram showing the reinforcing effect of the calcareous sandy soil after a sand-soil column is formed by adopting biological consolidation.

FIG. 6 is a scanning electron micrograph of the soil mass.

Fig. 7 is a schematic view of a drill pipe being driven into the earth and delivering the mixed solution through a pumping mechanism.

Fig. 8 is an XRD pattern of the composite microbial carbonate cement.

Fig. 9 is an XRD pattern of the composite microbial carbonate cementitious material.

Fig. 10 is an SEM image of composite microbial carbonate cement cementitious calcareous sand.

Detailed Description

The present invention is described in further detail below, wherein the specific examples are described for the purpose of illustration only and are not to be construed as limiting the invention.

The method for reinforcing calcareous sandy soil and desert sand by using the novel microbial mineralized carbonate cementing material comprises the steps of mixing and reacting 10% of slaked lime or calcium nitrate, 20% of carbon-fixing bacteria, 10% of foamed carbon dioxide and the balance calcareous sandy soil and/or desert sand to form biological carbonate cement, and solidifying after the reaction is finished.