A composition for preparing an arid desert greening planting soil, an arid desert greening planting soil, and a method of preparing the same

Abstract

The present application relates to solid waste resource technology field, disclose a kind of composition for preparing arid desert afforestation planting soil, arid desert afforestation planting soil and preparation method thereof.The composition contains water-based drilling cuttings, desert soil, carbon fiber, fly ash, pH regulator, water;With the total volume of water-based drilling cuttings and desert soil is 1m 3 2, the content of carbon fiber is 3-5kg, the content of fly ash is 5-10kg, the content of pH regulator is 0.5-2kg, and the content of water is 20-50kg;The content volume ratio of water-based drilling cuttings and desert soil is 1-2:1.The arid desert afforestation planting soil prepared by the composition provided by the present application has suitable soil performance, effectively reduces the salt content, pH value and chlorine content, realizes efficient resource utilization of solid waste, and is suitable for most water-based drilling cuttings.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solid waste resource utilization, and particularly relates to a composition for preparing arid desert greening planting soil, arid desert greening planting soil and a preparation method thereof. BACKGROUND

[0002] Drilling cuttings refer to a kind of solid waste inevitably produced in the process of oil and gas exploitation, in which the formation rock in the wellbore (drilling hole) is the main solid phase component, and various chemical substances in the formation and drilling fluid are adhered. + The drilling cuttings are rich in a large amount of soil-forming elements and minerals. The clay, K

[0003] However, the drilling cuttings used for preparing arid desert greening planting soil still face many problems compared with the standard CJ / T 340-2016 "Greening planting soil", for example: (1) The pH of the drilling cuttings is seriously high, generally pH > 9; a large amount of KCl, NaCl and other salt materials are added in the drilling fluid, resulting in a serious high salt content and soluble chlorine; the clay content is high, and the soil is easy to be hardened after being contacted with water, which seriously restricts the survival and growth of plants. (2) The clay content and salt content in the arid desert soil are high, and the water content in the arid desert soil is low. (3) There is little available soil improvement material in the arid desert and surrounding areas, and the improvement cost is high.

[0004] CN112167004A discloses a method for preparing shale gas water-based drilling cutting soil, which comprises the following steps: S1, reducing the salt content of the water-based drilling cutting to less than 2 g / kg; S2, adding a microbial agent to the desalted water-based drilling cutting at 2% to 5% of the mass of the water-based drilling cutting, so that the oil content in the mixture is reduced to less than 826 mg / kg; S3, adding 20% to 40% of purple soil and 20% to 50% of cow manure fermentation product to the mixture at 20% to 40% of the mass of the water-based drilling cutting, and mixing uniformly to complete the preparation of the artificial soil. Through the desalination-microorganism-soil method, the water-based drilling cutting is harmlessly and resourcefully treated to form an artificial soil mainly composed of water-based drilling cutting and supplemented by cow manure fermentation product and purple soil. The artificial soil prepared by the method has good fertilizer and water retention performance, but it is very difficult for microorganisms to cultivate and reproduce in the natural environment of the desert soil, and a large amount of purple soil and cow manure fermentation product is difficult to obtain.

[0005] CN111100651A discloses an oil and gas field water-based drilling rock soil soil improvement agent and soil improvement method, and improved soil; the soil improvement agent is composed of biochar powder, polyacrylamide and fly ash, and the composition contents of various substances in the soil improvement agent are limited; the biochar in the soil improvement agent has the characteristics of high pH value, high carbon-nitrogen ratio, high porosity and strong adsorption capacity for soil nutrients, is not easily decomposed and utilized by microorganisms, has a long residual time, is beneficial to improving soil carbon fixation and improving soil physical and chemical properties; the anionic polyacrylamide is a water-soluble polymer, can effectively inhibit soil water evaporation, prevent water and soil loss, and improve soil structure and promote soil microbial development. The fly ash particles used in the scheme are in a porous honeycomb shape, have a large specific surface area and high adsorption activity, and can increase the content of silt in the rock debris; however, the pH value of the biochar is high, which is added to the high pH value of the drilling rock debris, increasing the alkalinity of the soil, and is not suitable for greening planting.

[0006] CN108949184A discloses a desert soil improvement agent and a desert soil improvement method thereof, and the raw material components of the improvement agent include diatomite, fly ash, bentonite, kaolin, grass carbon, plant straw powder, algal carrier, organic fertilizer, coated grass seed, humus, zeolite powder, glass microbeads, silica powder, microbial liquid and the like. The desert soil improvement agent is composed of sand-fixing components and nutrient components with a specific compatibility, and finally includes solid and liquid components, and has the effects of sand fixation and soil improvement. However, the microbial liquid is difficult to survive and reproduce in the arid desert environment, the raw material components of the improvement agent are complex, and contain a large amount of clay components such as diatomite, bentonite and kaolin, which are added to the high content of clay components in the drilling rock debris, and there is a risk of soil hardening, and the production cost is high, which is not conducive to large-scale application. SUMMARY

[0007] The purpose of the present application is to solve the problems of high pH value, high salt content and high chlorine content in the prior art for preparing arid desert greening planting soil from drilling rock debris.

[0008] In order to achieve the above purpose, the first aspect of the present application provides a composition for preparing arid desert greening planting soil, which contains the following components independently stored or mixedly stored:

[0009] Water-based drilling rock debris, desert soil, carbon fiber, fly ash, pH regulator and water;

[0010] The total volume of the water-based drilling rock debris and the desert soil is 1m 3 The content of the carbon fiber is 3-5kg, the content of the fly ash is 5-10kg, the content of the pH regulator is 0.5-2kg, and the content of the water is 20-50kg;

[0011] The content volume ratio of the water-based drilling cuttings and the desert soil is 1-2:1;

[0012] The pH value of the water-based drilling cuttings is 7-11, the moisture content is <50 wt%, the salt content is <50.0 g / kg, the soluble chlorine content is <1500.0 g / kg, the organic matter content is >12.0 mg / kg, the petroleum hydrocarbon content is <3000 mg / kg, and the average particle diameter is 5-100 μm;

[0013] The pH value of the desert soil is 7-8, the moisture content is <20 wt%, the salt content is <30.0 g / kg, the soluble chlorine content is <10.0 g / kg, the petroleum hydrocarbon content is <3000 mg / kg, the clay content is >5 wt%, and the average particle diameter is 0.85-15 mm;

[0014] The pH regulator is selected from at least one of humic acid, sulfur powder, superphosphate, and oxalic acid.

[0015] The second aspect of the present application provides a method for preparing the drought desert greening planting soil, which is prepared by using the composition of the first aspect, and comprises the following steps:

[0016] (1) first mixing the water-based drilling cuttings with the carbon fiber to obtain a mixture S1; and

[0017] second mixing the pH regulator with water to obtain a pH regulator solution;

[0018] (2) spreading the mixture S1 into a cuboid, building a cofferdam around the cuboid, and then injecting the pH regulator solution into the mixture S1 spread into the cuboid and airing;

[0019] (3) third mixing the mixture S1 with the desert soil and the fly ash to obtain the drought desert greening planting soil.

[0020] The third aspect of the present application provides the drought desert greening planting soil prepared by the method of the second aspect.

[0021] The drought desert greening planting soil prepared by using the composition provided by the present application has at least the following advantages:

[0022] (1) The specific kind of pH regulator and water are used in a specific ratio, and the specific drilling cuttings, desert soil and carbon fiber material are compounded, so that the drought desert greening planting soil prepared has suitable soil performance, and the salt content, pH value and chlorine content are effectively reduced.

[0023] (2) The composition for preparing the dry desert greening soil can directly utilize drilling cuttings with a pH value of 7-11, a water content of < 50 wt%, a salt content of < 50.0 g / kg and soluble chlorine of < 1500.0 g / kg, compared with the drilling cuttings with a salt content of < 22.0 g / kg utilized in the prior art, so that efficient resource utilization of solid waste is realized, and the composition is suitable for most water-based drilling cuttings.

[0024] (3) The method realizes the purpose of preparing a resource product in a dry area by consuming a large amount of drilling cuttings, has low cost and strong operability, and the addition of carbon fibers, desert soil and fly ash can improve the pores of the drilling cuttings and reduce the content of clay in the drilling cuttings, and on the other hand, the soil elements are supplemented, so that a new path and method are provided for safe disposal of a large amount of drilling cuttings in a desert area, and the method has good practical value and application prospect. DETAILED DESCRIPTION

[0025] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The endpoints of the ranges are included in the range. Any numerical value, however, can only be approximate. The numerical characteristics disclosed herein can vary by +1%. The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The ranges or values should be interpreted as including values approximating the recited ones. For numerical ranges, the endpoints of each range are included in the range, the endpoints of each range are included with the single point values, and the single point values are included with each other. New ranges can be created by combining the endpoints of the ranges or the single point values with each other.

[0026] As described above, the first aspect of the present application provides a composition for preparing a dry desert greening planting soil, which contains the following components, each of which is independently stored or both of which are mixed and stored:

[0027] Water-based drilling cuttings, desert soil, carbon fibers, fly ash, pH adjuster, water;

[0028] The total volume of the water-based drilling cuttings and the desert soil is 1 m 3 The content of the carbon fibers is 3-5 kg, the content of the fly ash is 5-10 kg, the content of the pH adjuster is 0.5-2 kg, and the content of the water is 20-50 kg;

[0029] The content volume ratio of the water-based drilling cuttings to the desert soil is 1-2:1;

[0030] The pH value of the water-based drilling cuttings is 7-11, the water content is < 50 wt%, the salt content is < 50.0 g / kg, the soluble chlorine is < 1500.0 g / kg, the organic matter is > 12.0 mg / kg, the petroleum hydrocarbon content is < 3000 mg / kg, and the average particle diameter is 5-100 μm;

[0031] The pH value of the desert soil is 7-8, the water content is <20wt%, the salt content is <30.0g / kg, the soluble chlorine content is <10.0g / kg, the petroleum hydrocarbon content is <3000mg / kg, the clay content is >5wt%, and the average particle diameter is 0.85-15mm.

[0032] The pH regulator is selected from at least one of humic acid, sulfur powder, calcium superphosphate and oxalic acid.

[0033] Preferably, the heavy metal content in the water-based drilling debris meets the requirements of CJ / T 340-2016 green planting soil.

[0034] The salt content, organic matter, petroleum hydrocarbon content and clay content of the water-based drilling debris and the desert soil are tested according to LY / T 1251 standard, NY / T1237 standard, HJ1021 standard and GB / T14684 standard respectively.

[0035] The average particle diameter of the water-based drilling debris and the desert soil is determined by Dandong Bettersize 2600E laser particle size instrument according to GB / T 19077-2016 particle size analysis laser diffraction method.

[0036] Preferably, the total volume of the water-based drilling debris and the desert soil is 1m 3 Preferably, the content of the carbon fiber is 3-5kg, the content of the fly ash is 6-10kg, the content of the pH regulator is 1-2kg, and the content of the water is 30-50kg.

[0037] The content volume ratio of the water-based drilling debris to the desert soil is 1-1.5:1. In this preferred case, the inventors find that the pH value, salt content and chlorine content of the obtained dry desert green planting soil are lower.

[0038] Preferably, the pH regulator is a combination of sulfur powder, calcium superphosphate and oxalic acid with a content mass ratio of 1:0.5-1.5:1-4. The inventors find that in this preferred case, the pH value of the obtained dry desert green planting soil is more suitable for soil performance.

[0039] Preferably, the carbon fiber is a product obtained by carbonizing treatment of crop straw, and the water content of the crop straw is <10wt%, and the straw length is <5cm.

[0040] It should be noted that the length of the crop straw refers to the length of the crushed crop straw.

[0041] Preferably, the crop straw is selected from at least one of cotton straw, wheat straw and reed straw.

[0042] Preferably, the carbonization treatment is performed at a temperature of 200-300°C for 0.5-1h. The inventors have found that, in this preferred case, the carbon fibers obtained can better improve the porosity of the drilling cuttings when used to prepare the arid desert greening planting soil.

[0043] Preferably, the fly ash has a specific surface area of 300-500m 2 / g, a density of 2.0-2.3g / cm 3 , a pore size of ≤20μm, and a water absorption of 20-30wt%. The inventors have found that, in this preferred case, the carbon fibers obtained can improve the porosity and adsorption performance of the drilling cuttings when used to prepare the arid desert greening planting soil.

[0044] As described above, the second aspect of the present application provides a method for preparing an arid desert greening planting soil, which uses the composition of the first aspect, and comprises:

[0045] (1) first mixing the water-based drilling cuttings with the carbon fibers to obtain a mixture S1; and

[0046] second mixing the pH regulator with water to obtain a pH regulator solution;

[0047] (2) spreading the mixture S1 into a cuboid, and building a cofferdam around the cuboid; then injecting the pH regulator solution into the mixture S1 spread into the cuboid, and airing;

[0048] (3) third mixing the mixture S1 with the desert soil and the fly ash to obtain the arid desert greening planting soil.

[0049] It should be noted that the definitions and amounts of the water-based drilling cuttings, the carbon fibers, the desert soil, the fly ash, and the pH regulator described in the present application are the same as those of the corresponding components described in the first aspect, and will not be repeated here, and those skilled in the art should not understand this as a limitation on the present application.

[0050] The present application does not particularly limit the manner of the first mixing, the second mixing, and the third mixing, and those skilled in the art can use known mixing methods, as long as the materials can be uniformly mixed. Exemplarily, the first mixing is performed at a stirring speed of 200-300rpm for 0.5-1h; the second mixing is performed at a stirring speed of 800-1200rpm for 0.5-1h; and the third mixing is performed at a stirring speed of 200-300rpm for 1.5-2.5h.

[0051] According to one preferred embodiment, in step (2), the height of the cofferdam is 0.1-0.2 m higher than the height of the cuboid.

[0052] According to another preferred embodiment, the conditions of the sunning include: temperature of 10-35℃, relative humidity of 31-78%, and time of 15-20 days.

[0053] Preferably, the method further comprises: in step (2), after spreading the mixture S1 into a cuboid, the cuboid is evenly divided into n small cuboids, and a ditch with a width of 2-3 m is arranged between every two small cuboids.

[0054] Preferably, the pH regulator solution is injected into the mixture S1 spread into a cuboid for 2-5 times.

[0055] As described above, the third aspect of the present application provides a dry desert afforestation planting soil prepared by the method of the second aspect.

[0056] The present application will be described in detail below by way of examples. In the following examples, the instruments, reagents, materials, etc. involved, if not specifically stated, are conventional instruments, reagents, materials, etc. in the prior art, which can be obtained through regular commercial channels.

[0057] Water-based drilling cuttings I: pH 7.5, water content 20wt%, salt content 25.5g / kg, soluble chlorine 503.0g / kg, organic matter 12.8mg / kg, petroleum hydrocarbon content 1200mg / kg, heavy metal content meets the requirements of CJ / T 340-2016 afforestation planting soil, average particle diameter 37.3μm, from Karamay Petrochemical Park water-based drilling cuttings harmless treatment station.

[0058] Water-based drilling cuttings II: pH 10.5, water content 48.5wt%, salt content 45.3g / kg, soluble chlorine 1462.0g / kg, organic matter 18.08mg / kg, petroleum hydrocarbon content 2850mg / kg, heavy metal content meets the requirements of CJ / T 340-2016 afforestation planting soil, average particle diameter 73.6μm; from Karamay Petrochemical Park water-based drilling cuttings harmless treatment station.

[0059] Water-based drilling cuttings III: pH 11.5, water content 62wt%, salt content 55.3g / kg, soluble chlorine 1855g / kg, organic matter 11.0mg / kg, petroleum hydrocarbon content 4200mg / kg, heavy metal content meets the requirements of CJ / T 340-2016 afforestation planting soil, average particle diameter 98.2μm, from Xinjiang Northwest drilling site.

[0060] Desert soil: pH 7.75, water content 16.2wt%, salt content 21.2g / kg, soluble chlorine 8.0g / kg, petroleum hydrocarbon content exceeding the detection limit (<6mg / kg), the clay content of the desert soil >5wt%, the average particle diameter is 2.54mm; from the gobi desert in the northwest of Junggar Basin.

[0061] Fly ash: specific surface area 365m 2 / g, density 2.15g / cm 3 , pore size 16.8μm, water absorption rate 25.7wt%, from fly ash of a thermal power plant in Xinjiang.

[0062] pH regulator I: a combination of sulfur powder, superphosphate, and oxalic acid with a mass ratio of 1:1:4.

[0063] pH regulator II: a combination of sulfur powder, superphosphate, and oxalic acid with a mass ratio of 1:1:1.

[0064] pH regulator III: oxalic acid, analytical grade, purchased from Chengdu Kolon Chemicals Co., Ltd.

[0065] Preparation of carbon fiber I:

[0066] Cotton straw with a water content of 8.5wt% was crushed into straw with a length of 2cm-4.5cm, and then carbonized under anaerobic conditions at 285℃ for 1h to obtain carbon fiber I.

[0067] Preparation of carbon fiber II:

[0068] Wheat straw with a water content of 7.2wt% was crushed into straw with a length of 2cm-3.5cm, and then carbonized under anaerobic conditions at 210℃ for 0.5h to obtain carbon fiber II.

[0069] Preparation of carbon fiber III:

[0070] Reed straw with a water content of 8.9wt% was crushed into straw with a length of 2cm-4.1cm, and then carbonized under anaerobic conditions at 235℃ for 0.5h to obtain carbon fiber III.

[0071] Example 1

[0072] This example is used to illustrate the preparation of the drought desert greening planting soil according to the formula and process parameters in Table 1 and the method as follows.

[0073] The method for preparing the drought desert greening planting soil from the drilling cuttings comprises:

[0074] (1) first mixing the water-based drilling cuttings with the carbon fiber to obtain a mixture S1; and

[0075] mixing the pH regulator with water to obtain a pH regulator solution;

[0076] The first mixing condition: stirring speed 200 rpm, time 1 h;

[0077] The second mixing condition: stirring speed 1000 rpm, time 0.5 h;

[0078] (2) The mixture S1 is spread into a cuboid with a height of 0.15 m, a cofferdam is built around the cuboid, the height of the cofferdam is 0.1 m higher than the height of the cuboid; the pH regulator solution is injected into the mixture S1 spread into the cuboid in 3 times, and is dried;

[0079] (3) The mixture S1 is mixed with desert soil and fly ash to obtain a dry desert greening planting soil;

[0080] The third mixing condition: stirring speed 200 rpm, time 2 h.

[0081] In the absence of special instructions, the rest of the examples adopt a similar process to Example 1, except that the formulations and process parameters used in each example are different, see Table 1 (the parameters not listed in Table 1 are the same as the corresponding parameters in Example 1).

[0082] Table 1

[0083]

[0084]

[0085] Comparative Example 1

[0086] This comparative example adopts a similar method to Example 1, except that the water-based drilling cuttings I is replaced with water-based drilling cuttings III in equal volume;

[0087] The remaining steps are the same as Example 1.

[0088] Comparative Example 2

[0089] This comparative example adopts a similar method to Example 1, except that the desert soil is replaced with water-based drilling cuttings I in equal volume;

[0090] The remaining steps are the same as Example 1.

[0091] Comparative Example 3

[0092] This comparative example adopts a similar method to Example 1, except that the carbon fiber I is replaced with fly ash in equal mass;

[0093] The remaining steps are the same as in Example 1.

[0094] Test Example

[0095] The green planting soil prepared in the above example and the Gobi desert poplar carbon sink forest green planting soil (as a reference for comparison) were tested for performance according to the CJ / T 340-2016 “Green planting soil” standard; the specific performance test results are shown in Table 2:

[0096] Table 2

[0097]

[0098] As can be seen from the above table, compared with the mature Gobi desert poplar carbon sink forest green planting soil, the arid desert green planting soil provided by the present application has a good corresponding relationship with it and has good arid desert green planting soil performance.

[0099] Application Example

[0100] An experiment was carried out in a certain Gobi desert area in Xinjiang according to a similar method to Example 1, specifically:

[0101] (1) 50 m 3 of water-based drilling cuttings that have reached the standard of DB65 / T3997-2017 were taken, 400 kg of carbon fiber I was added, and the mixture was uniformly mixed to obtain a mixture S1;

[0102] 100 kg of pH adjuster I was melted into 3000 kg of water, and the mixture was stirred uniformly to obtain a pH adjuster solution;

[0103] (2) The mixture S1 was spread flat to a height of 1.0 m, and then divided into 5 small rectangles, each with a length of 10 m, and a 2.5 m trench between each two small rectangles, and a cofferdam with a height of 0.2 m higher than the plane of the rectangle around each small rectangle; the above-mentioned pH adjuster solution was divided into 5 parts, and each part of the pH adjuster solution was injected into the mixture S1 spread into a small rectangle in 3 times, and the mixture was dried at 25°C and a relative humidity of 50% for 15 days;

[0104] (3) 50 m 3 of desert soil and 600 kg of fly ash were each divided into 5 parts, and 1 part of the desert soil and 1 part of the fly ash were added to each small piece of the mixture S1, and the mixture was uniformly mixed to obtain an arid desert green planting soil.

[0105] On May 20, 2023, 50 Xinjiang poplar seedlings were planted at the implementation point, and after 1 month of growth, 48 survived and grew, with a survival rate of 96%, which was higher than the survival rate of 95% of the artificial forest in the area.

[0106] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including that each technical feature is combined in any other suitable manner. These simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. A composition for preparing a dry desert greening planting soil, characterized by, The composition contains the following components which are independently stored or mixed together: water-based drilling cuttings, desert soil, carbon fiber, fly ash, pH regulator, water; with the total volume of the water-based drilling cuttings and desert soil being 1 m 3 kg, the content of the fly ash being 5-10 kg, the content of the pH regulator being 0.5-2 kg, and the content of the water being 20-50 kg. The content volume ratio of the water-based drilling cuttings to the desert soil is 1-2:1; The water-based drilling cuttings have a pH value of 7-11, a water content of <50 wt%, a salt content of <50.0 g / kg, a soluble chlorine content of <1500.0 g / kg, an organic matter content of >12.0 mg / kg, and a petroleum hydrocarbon content of <3000 mg / kg, and an average particle diameter of 5-100 μm; The desert soil has a pH value of 7-8, a water content of <20 wt%, a salt content of <30.0 g / kg, a petroleum hydrocarbon content of <3000 mg / kg, a clay content of >5 wt%, and an average particle diameter of 0.85-15 mm; The pH regulator is a combination of sulfur powder, superphosphate, and oxalic acid at a content mass ratio of 1:0.5-1.5:1-4.

2. The composition of claim 1, wherein, with the total volume of the water-based drilling cuttings and desert soil being 1 m 3 kg, the content of the fly ash being 6-10 kg, the content of the pH regulator being 1-2 kg, and the content of the water being 30-50 kg. The content volume ratio of the water-based drilling cuttings to the desert soil is 1-1.5:

1.

3. The composition according to claim 1 or 2, characterized in that, The carbon fiber is a product obtained by carbonizing crop stalks; the crop stalks have a water content of <10 wt% and a stalk length of <5 cm.

4. The composition of claim 3, wherein, The crop stalks are selected from at least one of cotton stalks, wheat stalks, and reed stalks; and / or The carbonization treatment is performed at a temperature of 200-300°C and in the absence of oxygen for 0.5-1 h.

5. The composition according to claim 1 or 2, characterized in that, The specific surface area of the fly ash is 300-500 m 2 / g, the density is 2.0-2.3 g / cm 3 , the pore size is ≤20 μm, and the water absorption is 20-30 wt%.

6. A method of preparing a re-vegetation planting soil for arid desert areas, characterized in that, The method uses the composition of any one of claims 1-5, and comprises: (1) first mixing the water-based drilling cuttings with the carbon fiber to obtain a mixture S1; and second mixing the pH regulator with water to obtain a pH regulator solution; (2) spreading the mixture S1 into a cuboid, building a cofferdam around the cuboid, and then injecting the pH regulator solution into the mixture S1 in the cuboid and airing; (3) third mixing the mixture S1 with the desert soil and the fly ash to obtain a dry desert greening planting soil.

7. The method of claim 6, wherein, In step (2), the height of the cofferdam is 0.1-0.2 m higher than the height of the cuboid.

8. The method according to claim 6 or 7, characterized in that, The airing is performed at a temperature of 10-35°C, a relative humidity of 31-78%, and for 15-20 days.

9. A dry desert greening planting soil prepared by the method of any one of claims 6-8.

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