Well drilling solid waste treatment method

Abstract

The invention provides a well drilling solid waste treatment method. The well drilling solid waste treatment method comprises the steps that well drilling solid waste is pretreated; carrying out deep treatment on the pretreated drilling solid waste; and carrying out tail gas treatment on the well drilling solid waste subjected to deep treatment. According to the well drilling solid waste treatment method, reduction, harmlessness, stabilization and recycling of well drilling solid waste are achieved through the three steps of pretreatment, deep treatment and tail gas treatment.

Description

Technical Field

[0001] The invention relates to the technical field of harmless treatment of drilling waste in the petroleum engineering industry, and in particular to a method for treating drilling solid waste. Background Art

[0002] A large amount of drilling waste is generated during the oil and gas exploration and development process. Due to the wide variety of harmful substances, complex composition and different degrees of harm, the economic cost and environmental impact need to be considered in the disposal process. At present, there is no mature technology at home and abroad that can achieve the complete resource utilization of drilling waste. During the oil and gas drilling operation, a large amount of drilling solid waste is generated. Traditional methods of drilling solid waste treatment have many problems and are difficult to meet the current requirements of environmental protection and resource utilization.

[0003] In the past, the pretreatment of drilling solid waste was often not detailed and comprehensive enough. When separating rock cuttings and muddy solid waste, it may be simply a preliminary separation without further crushing and cleaning of the rock cuttings, resulting in a large amount of impurities in the rock cuttings, limiting the subsequent utilization value. For the treatment of muddy solid waste, there may be no systematic flocculation and sedimentation process, or the selection and use of flocculants are inappropriate, resulting in poor flocculation effect and inability to effectively separate the supernatant and sediment, which in turn affects the subsequent oil-water separation and deep purification treatment, making it difficult to obtain high-quality purified water for reinjection or discharge.

[0004] In terms of deep treatment, traditional methods may lack effective pyrolysis technology to transform organic matter in muddy solid waste, resulting in a large amount of organic matter waste and possible environmental pollution. Or even if there is a pyrolysis process, there is no reasonable subsequent treatment method for the combustible gas produced by pyrolysis, and the gas cannot be harmless and resource-based.

[0005] The exhaust gas treatment link is also relatively weak. The exhaust gas generated by the pyrolysis process and the oil-water separation process may only be simply treated or even discharged directly without treatment, resulting in excessive levels of harmful substances in the exhaust gas such as sulfides and nitrogen oxides, causing serious pollution to the atmospheric environment. At the same time, it also does not meet the country's increasingly stringent environmental emission standards.

[0006] Existing drilling waste treatment methods all have certain defects, so there is an urgent need to develop a new drilling waste treatment technology to improve the purity of solid products and reduce the content of harmful substances, thereby achieving the reduction, harmlessness, stabilization and resource utilization of drilling waste. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a method for treating drilling solid waste, aiming to improve the purity of solid phase products and reduce the content of harmful substances, thereby achieving the reduction, harmlessness, stabilization and resource utilization of drilling waste.

[0008] In order to solve the above technical problems, the present invention adopts the following technical measures:

[0009] In a first aspect, the present invention provides a method for treating drilling solid waste, comprising:

[0010] Pre-treatment of drilling solid waste;

[0011] Conduct deep treatment on pre-treated drilling solid waste;

[0012] The tail gas of drilling solid waste after deep treatment is treated.

[0013] Furthermore, the preprocessing includes:

[0014] Separate the rock cuttings from the muddy solid waste in the drilling solid waste;

[0015] Cleaning the separated rock cuttings;

[0016] Drying the cleaned cuttings;

[0017] Carry out flocculation and sedimentation treatment on slurry solid waste;

[0018] Carry out oil-water separation treatment on the muddy solid waste after flocculation and sedimentation treatment;

[0019] The muddy solid waste after oil-water separation treatment is deeply purified.

[0020] Furthermore, before the flocculation and sedimentation treatment of the slurry solid waste, the process further comprises:

[0021] After separating the rock cuttings in the drilling solid waste from the muddy solid waste, crushing the separated rock cuttings;

[0022] Clean the crushed rock cuttings.

[0023] Furthermore, the flocculation and sedimentation treatment of the slurry solid waste includes:

[0024] Adding a flocculant to the slurry-like solid waste to form a flocculation reaction tank;

[0025] Stirring the flocculation reaction tank to form a flocculation sedimentation tank;

[0026] The flocculation sedimentation tank is allowed to stand to form a supernatant and a precipitate;

[0027] performing oil-water separation treatment on the supernatant;

[0028] The precipitate is dried and pyrolyzed.

[0029] Furthermore, the deep purification of the muddy solid waste after the oil-water separation treatment includes:

[0030] The muddy solid waste after the oil-water separation treatment is sequentially treated by activated carbon adsorption and ion exchange resin to form treated water.

[0031] Furthermore, the tail gas treatment of the deep-treated drilling solid waste includes:

[0032] The tail gas generated by the pyrolysis process and the oil-water separation process is treated by spray absorption and catalytic oxidation.

[0033] The beneficial effects of the present invention are as follows:

[0034] The drilling solid waste treatment method provided by the present invention realizes the reduction, harmlessness, stabilization and resource utilization of drilling solid waste through the three steps of pretreatment, deep treatment and tail gas treatment. Among them, in the pretreatment stage, large-particle rock cuttings in the drilling solid waste are screened out by mechanical sieve filtration, and washed and dried, and then the remaining muddy solid waste is subjected to flocculation precipitation, oil-water separation and deep purification treatment, and finally purified water that can be used for reinjection or discharge and dry rock cuttings that can be used as building materials are obtained. In the deep treatment stage, the organic matter in the muddy solid waste is mainly converted into combustible gas by pyrolysis, and then converted into carbon dioxide and water through subsequent spray absorption and catalytic oxidation treatment for discharge, thereby realizing the harmless treatment of the gas. In the tail gas treatment stage, the tail gas generated by the pyrolysis process and the oil-water separation process is subjected to spray absorption and catalytic oxidation treatment, so that it meets the national emission standards before being discharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0036] For the purpose of the following detailed description, it should be understood that the present invention may adopt various alternative changes and step sequences, unless expressly specified to the contrary. In addition, except in any operating examples, or otherwise indicated, all numbers representing the amount of ingredients used in the specification and claims should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters set forth in the following specification and the attached claims are approximate values ​​that vary according to the desired performance to be obtained by the present invention. At least it is not intended to limit the application of the doctrine of equivalents to the scope of the claims, and each numerical parameter should at least be interpreted according to the number of reported significant figures and by applying ordinary rounding techniques.

[0037] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0038] In addition, it should be understood that any numerical range described herein is intended to include all subranges subsumed therein. For example, a range of "1 to 10" is intended to include all subranges between (and including) the stated minimum value of 1 and the stated maximum value of 10, i.e., having a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0039] The present invention provides a method for treating drilling solid waste, such as Figure 1 As shown, including:

[0040] S100, pre-treating drilling solid waste;

[0041] S200, deep processing the pre-treated drilling solid waste;

[0042] S300, treating the tail gas of the deep-treated drilling solid waste.

[0043] In this embodiment, the drilling solid waste is first pretreated, including: separating the rock cuttings in the drilling solid waste from the muddy solid waste; cleaning the separated rock cuttings; drying the cleaned rock cuttings; performing flocculation and sedimentation treatment on the muddy solid waste; performing oil-water separation treatment on the muddy solid waste after the flocculation and sedimentation treatment; and performing deep purification treatment on the muddy solid waste after the oil-water separation treatment.

[0044] In this embodiment, before the flocculation and sedimentation treatment of the muddy solid waste, the following steps are further performed: separating the rock cuttings in the drilling solid waste from the muddy solid waste, and then crushing the separated rock cuttings; and washing the crushed rock cuttings.

[0045] In this embodiment, the flocculation and sedimentation treatment of the muddy solid waste includes: adding a flocculant to the muddy solid waste to form a flocculation reaction tank; stirring the flocculation reaction tank to form a flocculation sedimentation tank; allowing the flocculation sedimentation tank to stand to form a supernatant and a precipitate; performing oil-water separation treatment on the supernatant; and drying and pyrolysis treatment on the precipitate.

[0046] In this embodiment, deep purification of the muddy solid waste after oil-water separation treatment includes: subjecting the muddy solid waste after oil-water separation treatment to activated carbon adsorption and ion exchange resin treatment in sequence to form treated water.

[0047] In this embodiment, the tail gas treatment of the deep-treated drilling solid waste includes: spraying absorption and catalytic oxidation treatment of the tail gas generated in the pyrolysis process and the oil-water separation process.

[0048] The drilling solid waste treatment method provided by the present invention realizes the reduction, harmlessness, stabilization and resource utilization of drilling solid waste through the three steps of pretreatment, deep treatment and tail gas treatment. Among them, in the pretreatment stage, large-particle rock cuttings in the drilling solid waste are screened out by mechanical sieve filtration, and washed and dried, and then the remaining muddy solid waste is subjected to flocculation precipitation, oil-water separation and deep purification treatment, and finally purified water that can be used for reinjection or discharge and dry rock cuttings that can be used as building materials are obtained. In the deep treatment stage, the organic matter in the muddy solid waste is mainly converted into combustible gas by pyrolysis, and then converted into carbon dioxide and water through subsequent spray absorption and catalytic oxidation treatment for discharge, thereby realizing the harmless treatment of the gas. In the tail gas treatment stage, the tail gas generated by the pyrolysis process and the oil-water separation process is subjected to spray absorption and catalytic oxidation treatment, so that it meets the national emission standards before being discharged.

[0049] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for treating drilling solid waste, characterized in that: include: Pre-treatment of drilling solid waste; Conduct deep treatment on pre-treated drilling solid waste; The tail gas of drilling solid waste after deep treatment is treated.

2. The method according to claim 1, characterized in that The pretreatment includes: separating the rock cuttings in the drilling solid waste from the muddy solid waste; washing the separated rock cuttings; drying the washed rock cuttings; performing flocculation and sedimentation treatment on the muddy solid waste; performing oil-water separation treatment on the muddy solid waste after the flocculation and sedimentation treatment; and performing deep purification treatment on the muddy solid waste after the oil-water separation treatment.

3. The method according to claim 2, characterized in that Before the flocculation and sedimentation treatment of the muddy solid waste, the method further includes: separating the rock cuttings in the drilling solid waste from the muddy solid waste, crushing the separated rock cuttings; and washing the crushed rock cuttings.

4. The method according to claim 3, characterized in that The flocculation and sedimentation treatment of the muddy solid waste includes: adding a flocculant to the muddy solid waste to form a flocculation reaction tank; stirring the flocculation reaction tank to form a flocculation sedimentation tank; allowing the flocculation sedimentation tank to stand to form a supernatant and a precipitate; performing oil-water separation treatment on the supernatant; and drying and pyrolysis treatment on the precipitate.

5. The method according to any one of claims 2 to 4, characterized in that: The deep purification treatment of the muddy solid waste after the oil-water separation treatment includes: subjecting the muddy solid waste after the oil-water separation treatment to activated carbon adsorption and ion exchange resin treatment in sequence to form treated water.

6. The method according to any one of claims 2 to 4, characterized in that: The tail gas treatment of the deep-treated drilling solid waste includes: spraying absorption and catalytic oxidation treatment of the tail gas generated in the pyrolysis process and the oil-water separation process.

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