CN103276719A - Apparatus and method for stabilizing clay by microbiological-electroosmosis processes - Google Patents

Abstract

The invention discloses a device and method for combining microorganism-electroosmosis to strengthen clay. The device includes a culture dish, a nutrient solution container, a DC power supply, a microorganism-electroosmosis device, a thermometer, and a cooling device; the method includes the following steps: (a) the microorganism - The cathode and anode of the electroosmosis device are respectively buried on both sides of the soil to be treated, and the thermometer is inserted into the center line of the treated soil; the culture dish and the nutrient solution container are placed close to the microorganism-electroosmosis device; (b) the culture dish is loaded For Bacillus pasteuriani, the nutrient solution container is filled with urea dissolved in calcium salt; the bacteria are cultivated; the urea nutrient solution mixed with bacteria and dissolved in calcium salt is injected into the electroosmosis device and the soil; (c) DC power supply Electroosmosis is carried out, and the temperature is controlled below 50°C. Compared with the prior art, the present invention has the advantages of better reinforcement effect, high cost performance, easy operation and no weather influence.

Description

Apparatus and method for combined microbial-electroosmotic reinforcement of clay

technical field

The invention relates to a device and method for reinforcing clay.

Background technique

The technology of microbial reinforcement of sandy soil was proposed by scientist Jason T. Dejong in 2006, and the bacteria used are Bacillus pasteuru (hereinafter referred to as Bacillus pasteuru). This strain is a strain capable of aerobic respiration. If it is cultivated in moist sandy soil with urea and calcium-dissolved liquid, it can produce metabolite calcium carbonate between soil particles, and calcium carbonate will stick between soil particles. , thereby improving the shear resistance of sandy soil. However, this method is only applicable to sandy soil, and cannot be realized in other soils or projects, and has limitations. Reuss first discovered electroosmosis in clay in 1809, and Casagrande first applied electroosmosis to civil engineering in 1939. After that, scholars from various countries have carried out some research work on the mechanism and application of electroosmosis. Electroosmosis is achieved by applying a direct current electric field to the soil. Since the fine-grained soil is usually negatively charged, there are hydration cations balanced with it in the pore water. Under the action of the electric field, the hydration cations move to the negative electrode and drive the water molecules to move together. drain. The construction load of the electroosmosis method is small, and the drainage speed mainly depends on the electric permeability rather than the hydraulic permeability of the soil. It can quickly discharge the free water and some weakly bound water in the soil, so it is only suitable for silt and silt with low permeability coefficient. Clay and sludge drainage, etc.

Contents of the invention

Purpose of the invention: The purpose of the present invention is to provide a more uniform and better treatment of clay and silt reinforcement problems in view of the deficiencies in the prior art, and the cost is not much, and the cost-effective microorganism-electroosmosis joint reinforcement clay device and methods.

Technical solution: In order to achieve the purpose of the present invention, the present invention discloses a device for joint reinforcement of microorganism-electroosmosis, including a culture dish, a nutrient solution vessel, a DC power supply, a microorganism-electroosmosis device, a thermometer, and a cooling device; The positive electrode is connected to the anode of the microorganism-electroosmosis device through a wire; the negative electrode of the DC power supply is connected to the cathode of the microorganism-electroosmosis device through a wire; the cooling device includes a cooling chamber, a compressor, an outlet pipe and a return pipe; the microorganism-electroosmosis device The anode consists of an alternate arrangement of carbon rods and zigzag steel plates, and the carbon rods are hollow.

The present invention also discloses the method for this microorganism-electroosmosis joint reinforcement clay, comprising the following steps:

(a) Embed the cathode and anode of the microorganism-electroosmosis device on both sides of the soil to be treated, insert the thermometer into the center line of the treated soil with 3 to 4 carbon rods as the cathode, and surround the water pipe of the cooling device Bury the thermometer in the soil; connect the positive pole of the DC power supply to the anode of the microorganism-electroosmosis device through a wire; connect the negative pole of the DC power supply to the cathode of the microorganism-electroosmosis device through a wire; Electroosmosis device placement;

(b) The petri dish is loaded with Bacillus pasteuriana, and the nutrient solution container is filled with urea dissolved in calcium salt; the bacteria are cultivated; the urea nutrient solution mixed with bacteria and dissolved in calcium salt is injected into the electroosmosis device and the soil ;

(c) The DC power supply is energized for electroosmosis, and bacteria and nutrient solution are continuously injected during electroosmosis; at the same time, if the temperature of the thermometer reaches above 50°C, start the cooling device to implement cooling.

Wherein (b) the strain culture time in the step is 2 to 5 hours. (c) The electrode unit voltage of the microorganism-electroosmosis device in the step is 0.5 to 2 V/cm; the electroosmosis construction time is 3 to 4 days.

Beneficial effects: Compared with the prior art, the present invention has the remarkable advantage that the advantages of the electroosmotic technology are fully utilized. When the soil body is not reinforced, the porosity is relatively high, and the gap between calcium precipitated and cemented soil particles is generated by the microbial cementation technology. At the same time, electroosmosis is carried out to discharge free water and weakly bound water, so that the soil reinforcement effect can be more effectively improved, and the reinforcement effect is much better than that of simple microbial cementation or electroosmosis; during the electroosmosis process, there will be anode and cathode Bubbles are generated to increase the interface resistance, increase the soil temperature, thereby increasing the activity of bacterial metabolic enzymes, promoting the generation of calcium precipitation, and improving the reinforcement effect; there are not many additional processes on the basis of the simple microbial cementation method, and the existing ones can be fully utilized. It is a very cost-effective soft soil treatment method; the device and method can be carried out in wet soil, and will not be affected by weather changes such as rain.

Description of drawings

Fig. 1 is the device of the present invention for joint consolidation of microorganisms and electroosmosis.

Detailed ways

The present invention will be further described below in conjunction with the figures.

As shown in Figure 1, the device of microorganism-electroosmosis joint reinforcement clay of the present invention comprises culture dish 1, nutrient solution container 2, DC power supply 3, microorganism-electroosmosis device 4, thermometer 5 and cooling device 6; DC power supply 3 The positive pole of the DC power supply is connected to the anode of the microorganism-electroosmosis device 4 by a wire; the negative pole of the DC power supply 3 is connected to the cathode of the microorganism-electroosmosis device 4 by a wire; the cooling device 6 includes a cooling chamber, a compressor, an outlet pipe and a return pipe; a thermometer 5 placed on the center line of the cathode and anode carbon rods of the microorganism-electroosmosis device 4; the outlet pipe and the return pipe of the cooling device 6 are zigzag arranged between the cathode and anode carbon rods of the microorganism-electroosmosis device 4, and connected with the carbon rods Parallel and equal in length; the anode of the microorganism-electroosmotic device 4 includes carbon rods 42 and zigzag steel plates 41 arranged alternately, the carbon rods 42 are hollow, and the cathode carbon rods have no specified shape. When using this device for clay reinforcement works, the following steps are included:

(a) Embed the cathode and anode of the microorganism-electroosmosis device 4 into the two sides of the soil to be treated respectively, insert the thermometer 5 into the center line of the treated soil with 3 to 4 carbon rods as the cathode, and place the The water pipe is buried in the soil around the thermometer; the positive pole of the DC power supply 3 is connected to the anode of the microorganism-electroosmosis device 4 through a wire; the negative pole of the DC power supply 3 is connected to the cathode of the microorganism-electroosmosis device 4 through a wire; To cultivate microorganisms, place the petri dish 1 and the nutrient solution container 2 close to the microorganism-electroosmotic device 4, and perform general protection.

(b) Petri dish 1 is loaded with Bacillus pasteuriana, and urea is added for general culture. Pay attention to protect the petri dish to avoid interference from other bacteria and loss of strains; transfer an appropriate amount of bacteria in the petri dish to a new petri dish and Inject the urea nutrient solution dissolved with calcium salt for cultivation; inject the urea nutrient solution mixed with bacterial flora and dissolved with calcium salt into the electroosmosis device and the soil;

(c) 2 to 5 hours after the bacteria are injected, the DC power supply 3 is energized for electroosmosis to ensure that the DC voltage per unit length between the anode steel plate and carbon rod and the cathode carbon rod is 0.5 to 2V/cm; while electroosmosis continues Inject bacterial species and nutrient solution, during electroosmosis, part of the free water and weakly bound water in the soil will flow from the anode to the cathode, causing the soil to shrink, and quickly discharge the air bubbles generated on the anode and cathode, thereby reducing the interface resistance and improving the electroosmosis efficiency , while the calcium metabolites of microorganisms enhance the soil’s cohesion, and the soil will be further strengthened under the combined action of microorganisms and electroosmosis; at the same time, if the temperature of the thermometer 5 reaches above 50°C, start the cooling device 6 to implement cooling .

The time of joint construction varies from 3 to 4 days according to the soil quality of the reinforcement area, and the bacteria injection and electroosmosis are stopped when the joint construction does not increase the reinforcement effect.

In summary, compared with the prior art, the present invention has the advantages of:

Give full play to the advantages of electroosmosis technology. When the soil is not reinforced, the porosity is high. The gap between calcium precipitated cemented soil particles is generated by microbial cementation technology, and electroosmosis is performed at the same time to discharge free water and weakly bound water, so that it can be more Effectively improve the effect of soil reinforcement. The reinforcement effect is much better than that of simple microbial cementation or electroosmosis.

During the electroosmotic process, air bubbles will be generated at the anode and cathode, thereby increasing the interface resistance and increasing the soil temperature, thereby increasing the activity of bacterial metabolic enzymes, promoting the generation of calcium precipitation, and improving the reinforcement effect.

Electroosmosis is intervened in conjunction with microbial reinforcement, the total power consumption is not much, and the reinforcement effect is greatly improved. There are not many additional processes on the basis of the simple microbial cementation method, and the existing technology and processes can be fully utilized. It is a cost-effective soft soil treatment method.

The device and method can be carried out in moist soil without being affected by weather changes such as rain.

Claims (5)

1. the device of microorganism-electric osmose joint reinforcement clay is characterized in that, comprises culture dish (1), nutrient solution vessel (2), dc source (3), microorganism-electric osmose device (4), thermometer (5) and heat sink (6);

The positive pole of dc source (3) links to each other by the anode of lead with microorganism-electric osmose device (4); The negative pole of dc source (3) links to each other by the negative electrode of lead with microorganism-electric osmose device (4);

Heat sink (6) comprises cooling chamber, compressor, outlet pipe and return pipe;

The anode of microorganism-electric osmose device (4) comprise carbon-point (42) and square shape steel plate (41) between or arrange, carbon-point (42) is hollow.

2. require the method for a kind of microorganism-electric osmose joint reinforcement clay of 1 described microorganism-electric osmose joint reinforcement clay device as right to use, it is characterized in that, may further comprise the steps:

(a) cathode and anode of microorganism-electric osmose device (4) being imbedded the both sides of the soil of need handling respectively, is spacing with thermometer (5) with 3 to 4 carbon-points of negative electrode, inserts and handles native center line, and the water pipe of heat sink is imbedded in the soil around thermometer; The positive pole of dc source (3) is linked to each other by the anode of lead with microorganism-electric osmose device (4); The negative pole of dc source (3) is linked to each other by the negative electrode of lead with microorganism-electric osmose device (4); To place culture dish (1), nutrient solution vessel (2) near microorganism-electric osmose device (4) placement;

(b) culture dish (1) the Pasteur bacillus of packing into, nutrient solution vessel (2) are packed into and are dissolved with the urea of calcium salt; Carrying out bacterial classification cultivates; The urea nutrient solution that is mixed with flora, is dissolved with calcium salt is injected electric osmose device and soil;

(c) electric osmose is carried out in dc source (3) energising, continues to inject bacterial classification and nutrient solution in the time of electric osmose; Meanwhile, if the temperature of thermometer (5) reaches more than 50 ℃, start heat sink (6), implement cooling.

3. the method for a kind of microorganism as claimed in claim 2-electric osmose joint reinforcement clay is characterized in that, (b) the bacterial classification incubation time is 2 to 5 hours in the step.

4. the method for a kind of microorganism as claimed in claim 2-electric osmose joint reinforcement clay is characterized in that, (c) the electrode unit voltage of microorganism in the step-electric osmose device (4) is 0.5 to 2V/cm.

5. the method for a kind of microorganism as claimed in claim 2-electric osmose joint reinforcement clay is characterized in that, the electric osmose engineering time is 3 to 4 days.

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