Post-residue soil based on oil sludge microbiological treatment as well as method and application of post-residue soil

Abstract

The invention discloses after-residue soil based on oil sludge microbiological treatment and a method and application thereof, and belongs to the technical field of oil sludge resource utilization. According to the method, the pretreatment agent is adopted for pretreating the oil sludge tailings, then the pretreated oil sludge tailings replace loess to serve as a special curing agent of the roadbed material, the reliability of the tailings serving as the roadbed material is guaranteed, meanwhile, an optimized additive is added into the loess, the physical and chemical effects and the surface chemical effects of the loess are optimized, and the roadbed material quality is improved. The whole method can achieve resource utilization of the muck after the oil sludge treatment reaches the standard, meanwhile, excavation and utilization of loess are saved, and the method has important significance for reducing water and soil loss.

Description

Technical Field

[0001] The invention belongs to the technical field of oil sludge resource utilization, and in particular relates to post-sludge soil based on oil sludge microbial treatment and a method and application thereof. Background Art

[0002] Oil sludge is an inevitable product of oil exploration, mining, gathering and transportation, and wastewater (liquid) treatment. The amount of tailings after treatment is generally 1 / 4-1 / 3 of the initial amount of oil sludge. Since oil sludge is a hazardous waste, the final destination of the tailings is also strictly supervised by the environmental protection department, and the disposal cost is huge.

[0003] Relevant regulations clearly require enterprises to utilize solid waste generated during production. Industry and local standards require that the oil content of oil sludge should be less than 2% or 1% after treatment, and it can be used to pave oil well sites and grade roads. However, there are currently no unified technical specifications. The best way to dispose of oil sludge residue after treatment is to make it a resource.

[0004] In some areas, loess is widely distributed and has a thick soil layer. It is the main material for road subgrades, but its strong collapsibility brings many difficulties to highway line design, on-site construction, and later maintenance management. In order to ensure smooth lines during operation, highways have high requirements for the stability and durability of the subgrade. Therefore, it is necessary to optimize the subgrade filler to improve its engineering properties. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a post-sludge soil treated with oil sludge microorganisms and a method and application thereof, so as to solve the technical problem of strong collapsibility of loess roadbed.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention discloses a method for treating post-sludge soil based on oil sludge microorganisms, comprising the following steps:

[0008] Adding a pretreatment agent to the sprayed oil sludge tailings, plowing for pretreatment, and then airing to obtain pretreated oil sludge tailings;

[0009] In terms of mass percentage, the pretreatment agent consists of 35%-50% potassium ferrate, 30%-50% molecular sieve and 5%-20% nano titanium dioxide.

[0010] Furthermore, the spray-wetted oil sludge tailings are obtained by the following steps: spraying a phosphate solution on the evenly crushed oil sludge tailings to obtain the spray-wetted oil sludge tailings;

[0011] The humidity of the sprayed oil sludge tailings is 55%-75%; the humidity of the pretreated oil sludge tailings is 10%-15%.

[0012] Furthermore, the phosphate solution is obtained by mixing a NaH2PO4.H2O solution and a Na2HPO4 solution; the volume ratio of the NaH2PO4.H2O solution and the Na2HPO4 solution is 6.6:1; the concentrations of the aH2PO4.H2O solution and the Na2HPO4 solution are both 1 mol / L; and the pH value of the phosphate solution is 6.

[0013] Furthermore, the pretreatment agent is 0.5%-1.5% of the mass of the sprayed oil sludge tailings.

[0014] Furthermore, the molecular sieve is an X-type molecular sieve; the X-type molecular sieve is obtained by mixing SiO2 / Al2O3 with a molar ratio of 2 to 3.

[0015] The invention also discloses oil sludge tailings prepared by the treatment method.

[0016] The present invention also discloses the application of the above-mentioned oil sludge tailings, wherein the pretreated oil sludge tailings are used as a material for paving a roadbed, comprising the following steps:

[0017] S1: The pre-treated oil sludge tailings and the curing agent are mixed to obtain a roadbed material; the loess and the loess modifier are mixed to obtain an improved pavement material;

[0018] S2: After the pre-paved road is excavated, the roadbed material is first laid on the ground, and after rolling, the improved pavement material is laid, and then rolled again.

[0019] Further, in S1, the mass ratio of the pretreated oil sludge tailings to the curing agent is 1:1;

[0020] Measured in percentage by mass, the curing agent consists of 40% to 50% of slaked lime, 30% to 40% of silica fume, 5% to 10% of cement-based penetrating crystalline waterproof material, 5% to 10% of nano silicon dioxide particles, 1% to 2% of acrylate, 1% to 2% of redispersible latex powder and 0.5% to 1.5% of polyacrylamide.

[0021] Furthermore, in S1, the loess modifier includes sodium carboxymethyl cellulose, polypropylene fiber and polyvinyl acetate; the water content of the loess is 17%-21%;

[0022] The dosage of sodium carboxymethyl cellulose, polypropylene fiber and polyvinyl acetate is 0.2%-0.5%, 0.20%-0.5% and 0.1% of the mass of loess respectively.

[0023] Further, in S2, the mass ratio of the roadbed material to the improved pavement material is 1:1;

[0024] The excavation depth of the pre-paved road is 90-100 cm; the rolling treatment method is to carry out the rolling operations of static pressure → weak vibration → strong vibration → weak vibration → static pressure in sequence.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The invention discloses a method for treating slag after oil sludge microorganism treatment, wherein a pretreatment agent is used to pretreat the oil sludge tailings, and a specific pretreatment agent component can stabilize the structure of the oil sludge tailings, remove the remaining organic matter therein, adjust the composition and microstructure of the slag, and realize its cyclic and reasonable utilization, and realize the resource utilization of the slag after the oil sludge treatment meets the standards, and has broad application prospects.

[0027] The present invention also discloses the application of the post-residue soil obtained by the above-mentioned pretreatment method in paving a roadbed, which uses the pretreated oil sludge tailings instead of loess as a special curing agent for roadbed materials, thereby ensuring the reliability of the tailings as roadbed materials. At the same time, preferred additives are added to the loess to optimize the physical and chemical and surface chemical effects of the loess and improve the performance of the loess road surface. The whole method can realize the resource utilization of the residue soil after the oil sludge treatment meets the standards, while saving the excavation and utilization of loess, which is of great significance to reducing soil erosion. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0029] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0030] Herein, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0031] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0032] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0033] The present invention provides a method for treating slag soil based on oil sludge microorganisms, which completely removes the remaining organic matter in the slag soil, adjusts the composition and microstructure of the slag soil, and improves the performance and quality of road paving, comprising the following steps:

[0034] (1) Pretreatment agent for pretreatment of slag:

[0035] It is composed of potassium ferrate (K2FeO4), X-type molecular sieve (SiO2 / Al2O3 molar ratio = 2-3), and nano titanium dioxide (TiO2). The mass of potassium ferrate accounts for 35%-50% of the pretreatment agent, the mass of X-type molecular sieve accounts for 30%-50%, and the mass of nano titanium dioxide accounts for 5%-20%.

[0036] (2) Pretreatment process:

[0037] ①Spray a pH=6 stable phosphate solution (1 mol / L NaH2PO4.H2O solution: 1 mol / L Na2HPO4 solution in a volume ratio of 6.6:1) on the evenly crushed soil, and continuously till the soil while spraying the solution to control the soil moisture between 55% and 75%;

[0038] ② Pretreatment of slag soil: add pretreatment agent, the amount of treatment agent added is 0.5%-1.5% of the slag soil mass, and use tillage equipment to till the slag soil evenly under sunlight, once a day for three consecutive days. While tilling the slag soil, pay attention to add phosphate solution to ensure the moisture of the slag soil;

[0039] ③After the pretreatment is completed, the slag is dried in the sun to allow the moisture in it to evaporate fully to a slag moisture level of 10%-15%.

[0040] The present invention also provides a method for roadbed solidification using the above-mentioned pretreated oil sludge tailings. According to the soil characteristics of the tailings, a special curing agent is provided for using slag instead of loess as a roadbed material to ensure the reliability of slag as a roadbed material, comprising the following steps:

[0041] Step 1: (1) Curing agent composition: 45% by weight of slaked lime, 35% by weight of silica fume, 8% by weight of cement-based penetrating crystalline waterproof material, 8% by weight of nano-silicon dioxide particles with a size of 30nm-40nm, 1.5% by weight of acrylate, 1.5% by weight of redispersible latex powder, and 1% by weight of polyacrylamide.

[0042] (2) Roadbed material: It is composed of pre-treated sludge tailings and curing agent in a mixing ratio of 1:1. When paving, the roadbed materials are mixed evenly with a mixer at the paving site and then paved.

[0043] Step 2: Loess modifier: sodium carboxymethyl cellulose CMC (0.2%-0.5% of loess), polypropylene fiber (0.20%-0.5% of loess), polyvinyl acetate STW (0.1% of loess).

[0044] Control conditions: maintain the loess moisture content at 17%-21%, crush the loess, and evenly mix the loess improver into the loess according to the added ratio to obtain improved pavement material.

[0045] After the upper layer of loess is paved and compacted, and the road is paved, a layer of anti-resistant solution is sprayed on the road surface after the loess is paved. The solution concentration is 0.1%-0.5%. When spraying, use an atomizer to wet the ground evenly. No liquid should accumulate on the road surface. After the road surface is dry, operate as before and spray twice more.

[0046] After the road surface is dry, no pedestrians or vehicles are allowed to pass through it for 72 hours to keep the road surface thoroughly consolidated.

[0047] Step 3: Road paving

[0048] Roadbed paving: paving in layers. The bottom layer is paved after pre-treatment of slag and curing agent mixed evenly; the upper layer is paved with improved loess.

[0049] (1) Materials: Improved pavement material: pre-treated oil sludge tailings: curing agent = 1:1; the surface is paved with improved pavement material.

[0050] (2) Layered paving: The pre-paved road excavation depth is about 90 cm, and the paving and compaction are carried out in layers according to the depth. The bottom layer is paved with pre-treated slag and roadbed materials with uniform curing agent, and the surface layer is paved with improved pavement materials.

[0051] The compaction method is: layered rolling, and each layer is laid according to the complete rolling operation of "static pressure → weak vibration → strong vibration → weak vibration → static pressure".

[0052] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0053] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0054] Example 1

[0055] (1) Pretreatment of slag

[0056] A pH=6 stable phosphate solution (1 mol / L NaH2PO4.H2O solution: 1 mol / L Na2HPO4 solution volume ratio = 6.6:1) is sprayed on the evenly crushed slag, and the slag is continuously tilled while the solution is sprayed to control the humidity of the slag between 55% and 75%.

[0057] Add pretreatment agent, the amount of treatment agent added is 1.5% of the mass of the slag, and use tillage equipment to evenly till the slag under sunlight, once a day for three consecutive days. While tilling the slag, pay attention to adding phosphate solution to ensure the moisture of the slag, and obtain the pretreated oil sludge tailings;

[0058] The pretreatment agent is composed of 40% potassium ferrate, 50% X-type molecular sieve (SiO2 / Al2O3 with a molar ratio of 2 to 3) and 10% nano titanium dioxide;

[0059] After the pretreatment is completed, the slag is dried to allow the moisture in it to evaporate fully to a slag moisture content of 10%-15%.

[0060] (2) Preparation before laying roadbed

[0061] The width, compaction, elevation, flatness, longitudinal and transverse slopes of the underlying layer should be inspected and accepted, and water should be sprinkled before adding soil to keep the base moist.

[0062] (3) Construction layout

[0063] To restore the center line of the roadbed, a pile is driven every 20 meters, and indicator piles are set outside the edge; the design height of the edge of the improved soil is marked clearly on the indicator piles.

[0064] (4) Roadbed solidification

[0065] Mix the pre-treated oil sludge tailings with the curing agent in a ratio of 1:1, and use a mixer to fully mix the roadbed materials; mix until the mixture is uniform and has a consistent color, without gray strips, gray clumps, and flowery surfaces, and spread evenly after mixing to obtain the roadbed materials; after paving and leveling, start rolling; compaction should follow the principle of "light first, heavy later, static first, vibration later, low first, high later, slow first, fast later, and overlapping wheel tracks". After compaction, the surface should be flat, without wheel tracks or bulging cracks, washboards, loose skin, etc.

[0066] The curing agent is composed of 45% slaked lime, 35% silica fume, 8% cement-based permeable crystalline waterproof material, 8% nano-silicon dioxide particles, 1.5% acrylate, 1.5% redispersible latex powder and 1% polyacrylamide.

[0067] (5) Road paving

[0068] The moisture content of loess is maintained at 17%-21%, the loess is crushed and sieved (sieve hole diameter 3mm), 0.3% sodium carboxymethyl cellulose CMC (loess mass ratio), 0.3% polypropylene fiber (loess mass ratio), 0.1% polyvinyl acetate STW (loess mass ratio) are uniformly mixed in the loess to obtain an improved pavement material; the upper loess of the improved pavement material is paved and compacted, and after the road paving is completed, a layer of anti-resistant solution is sprayed on the pavement after the improved pavement material is paved, and the solution concentration is 0.1%-0.5%. During spraying, an atomizer is used to wet the ground evenly, and no liquid can be formed on the road surface. After the road surface is dry, the same operation as before is performed, and then sprayed twice.

[0069] (6) Health preservation

[0070] After rolling is completed, the compaction degree, elevation, thickness, strength and other indicators are tested in time, and water is sprinkled for maintenance after passing the test. After the road surface is dried, no pedestrians or vehicles can pass through it within 72 hours to ensure that the road surface is completely consolidated.

[0071] Example 2

[0072] Different from Example 1, the pretreatment agent in Example 2 is composed of 35% potassium ferrate, 50% molecular sieve and 15% nano titanium dioxide, the curing agent is composed of 44.5% slaked lime, 30% silica fume, 10% cement-based penetrating crystalline waterproof material, 10% nano silicon dioxide particles, 2% acrylate, 2% redispersible latex powder and 1.5% polyacrylamide, and the rest of the methods are the same as in Example 1.

[0073] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for treating post-sludge soil based on oil sludge microorganisms, characterized in that: The following steps are involved: Adding a pretreatment agent to the wetted oil sludge tailings, plowing for pretreatment, and then airing to obtain pretreated oil sludge tailings; In terms of mass percentage, the pretreatment agent consists of 35%-50% potassium ferrate, 30%-50% molecular sieve and 5%-20% nano titanium dioxide.

2. The method for treating post-sludge soil based on oil sludge microorganisms according to claim 1, characterized in that: The spray-wetted oil sludge tailings are obtained by the following steps: spraying a phosphate solution on the evenly crushed oil sludge tailings to obtain the spray-wetted oil sludge tailings; The humidity of the sprayed oil sludge tailings is 55%-75%; the humidity of the pretreated oil sludge tailings is 10%-15%.

3. The method for treating post-sludge soil based on oil sludge microorganisms according to claim 2, characterized in that: The phosphate solution is obtained by mixing a NaH2PO4.H2O solution and a Na2HPO4 solution; the volume ratio of the NaH2PO4.H2O solution and the Na2HPO4 solution is 6.6:1; the concentrations of the aH2PO4.H2O solution and the Na2HPO4 solution are both 1 mol / L; the pH value of the phosphate solution is 6.

4. The method for treating post-sludge soil based on oil sludge microorganisms according to claim 1, characterized in that: The pretreatment agent accounts for 0.5%-1.5% of the mass of the sprayed oil sludge tailings.

5. The method for treating post-sludge soil based on oil sludge microorganisms according to claim 1, characterized in that: The molecular sieve is an X-type molecular sieve; the X-type molecular sieve is obtained by mixing SiO2 / Al2O3 in a molar ratio of 2 to 3.

6. A pretreated oil sludge tailing, characterized in that: The oil sludge is prepared by the method according to any one of claims 1 to 5 based on the treatment of sludge microorganisms.

7. The use of the pretreated oil sludge tailings according to claim 6, characterized in that: The pre-treated oil sludge tailings are used as materials for paving roadbed, comprising the following steps: S1: The pre-treated oil sludge tailings and the curing agent are mixed to obtain a roadbed material; the loess and the loess modifier are mixed to obtain an improved pavement material; S2: After the pre-paved road is excavated, the roadbed material is first laid on the ground, and after rolling, the improved pavement material is laid, and then rolled again.

8. The use of pretreated oil sludge tailings according to claim 7, characterized in that: In S1, the mass ratio of the pretreated oil sludge tailings to the curing agent is 1:1; Measured in percentage by mass, the curing agent consists of 40% to 50% of slaked lime, 30% to 40% of silica fume, 5% to 10% of cement-based penetrating crystalline waterproof material, 5% to 10% of nano silicon dioxide particles, 1% to 2% of acrylate, 1% to 2% of redispersible latex powder and 0.5% to 1.5% of polyacrylamide.

9. The use of pretreated oil sludge tailings according to claim 7, characterized in that: In S1, the loess improver includes sodium carboxymethyl cellulose, polypropylene fiber and polyvinyl acetate; the water content of the loess is 17%-21%; The dosage of sodium carboxymethyl cellulose, polypropylene fiber and polyvinyl acetate is 0.2%-0.5%, 0.20%-0.5% and 0.1% of the mass of loess respectively.

10. The use of pretreated oil sludge tailings according to claim 7, characterized in that: In S2, the mass ratio of the roadbed material to the improved pavement material is 1:1; The excavation depth of the pre-paved road is 90-100 cm; the rolling treatment method is to carry out the rolling operations of static pressure, weak vibration, strong vibration, weak vibration and static pressure in sequence.