A method for harmless treatment of waste acid residue of petroleum sulfonate plant

Abstract

The application discloses a harmless treatment method for waste acid residue of a petroleum sulfonate device. The method comprises the following steps: S1, delivering a dissolving solution to a first-stage dissolving tank; S2, placing an acid residue containing tank close to a feeding port side of the first-stage dissolving tank, fixing a sprayer above the acid residue containing tank, and connecting a dissolving solution circulating line to an outlet of a second-stage dissolving tank; S3, making the dissolving solution in the first-stage dissolving tank flow into the second-stage dissolving tank, and making the dissolving solution circulate in the first-stage dissolving tank and the second-stage dissolving tank; S4, after the circulation is stable, making the dissolving solution flow out through a spraying pipe to flush the acid residue in the acid residue containing tank, slowly adding the dissolved soft acid residue into the first-stage dissolving tank, and completing residue adding; after the acid residue is fully dissolved, a mixed solution of the dissolved acid residue is obtained; and S5, separating the mixed solution of the dissolved acid residue; and collecting a liquid phase part after the separation into a dissolving solution intermediate tank. The method can quickly and efficiently recover effective components, realizes harmless treatment of the acid residue, and reduces the risk of environmental pollution.

Description

Technical fields:

[0001] This invention relates to the field of hazardous waste treatment technology, and in particular to a method for the harmless treatment of waste acid residue from a petroleum sulfonate plant. Background technology:

[0002] Membrane sulfonation continuous production units for oil displacement petroleum sulfonates generate byproducts such as acid sludge and waste acid during the production process, particularly in gas-liquid separators and acid mist settling separators. This acid sludge affects the interfacial activity of the petroleum sulfonate products and can lead to excessive inorganic salt content. Furthermore, due to its high viscosity, the acid sludge can easily clog material pipelines, adhere to pump cavities affecting pump efficiency, and adhere to the inner walls of heat exchangers, reducing heat exchange efficiency. Current treatment methods involve manual cleaning followed by disposal as industrial hazardous waste, increasing the risk of environmental pollution. Summary of the Invention:

[0003] This invention addresses the problem in the prior art where existing manual cleaning methods result in increased environmental pollution risks due to the disposal of industrial hazardous waste. Instead, it provides a method for the harmless treatment of waste acid sludge from petroleum sulfonate plants. This method enables rapid and efficient recovery of effective components, while the separated insoluble components can be treated as general solid waste, thus achieving the harmless treatment of the acid sludge and reducing the risk of environmental pollution.

[0004] The present invention solves its problem through the following technical solution: a method for harmlessly treating waste acid residue from a petroleum sulfonate plant, comprising the following steps:

[0005] S1. After the preparation work is completed, prepare the dissolving solution; transport the prepared dissolving solution to the primary dissolving tank through the dissolving solution delivery pump; maintain the temperature at 60-70℃; the primary dissolving tank is connected to the secondary dissolving tank through an intermediate pipeline; the outlet of the secondary dissolving tank is connected to the dissolving solution circulation line;

[0006] S2. Place the acid residue holding tank near the feed port of the primary dissolving tank, and fix the sprayer above the acid residue holding tank; connect the sprayer to the dissolving liquid circulation line with a hose;

[0007] S3. Open the bottom valve of the primary dissolving tank to allow the solution in the primary dissolving tank to flow into the secondary dissolving tank by gravity through the intermediate pipeline. When the secondary dissolving tank reaches a certain level, turn on the solution circulation pump to establish a circulation between the primary and secondary dissolving tanks.

[0008] S4. After the solution has circulated and stabilized in the primary and secondary dissolving tanks, open the feed port of the primary dissolving tank, tilt the acid sludge holding tank, and simultaneously open the valve of the solution circulation line leading to the spray pipe, allowing the solution to flow out through the spray pipe to flush the acid sludge in the acid sludge holding tank. Gradually increase the tilt angle of the acid sludge holding tank and slowly add the dissolved, soft acid sludge into the primary dissolving tank. After the sludge is added, close the spray pipe valve and the feed port; turn on the agitator in the primary dissolving tank to stir, ensuring that the acid sludge is fully dissolved to obtain a mixed solution of dissolved acid sludge.

[0009] S5. The secondary dissolving tank is connected to the centrifuge via a dissolving liquid circulation line. Opening the valve at the centrifuge inlet of the dissolving liquid circulation line will transport the mixture of dissolved acid residue circulating in the dissolving tank to the centrifuge for separation. The insoluble matter is collected in a bucket at the centrifuge outlet. After separation by the centrifuge, the liquid phase enters the intermediate dissolving liquid tank for collection.

[0010] Further, step S1 preparation includes: connecting the waste acid residue harmless treatment system of the petroleum sulfonate unit, the system including a dissolving solution preparation tank, which is connected to the feed lines for solvent, water and alkali; the outlet of the dissolving solution preparation tank is connected to a primary dissolving tank via a dissolving solution transfer pump; the primary dissolving tank is equipped with a stirrer; the primary dissolving tank is connected to a secondary dissolving tank via an intermediate pipeline; a filter is connected to the intermediate pipeline; the outlet of the secondary dissolving tank is connected to a sprayer, the primary dissolving tank and a centrifuge via a dissolving solution circulation line; a dissolving solution circulation pump is connected to the dissolving solution circulation line; an acid residue holding tank is placed at the feed port of the primary dissolving tank, and a sprayer is fixed above the acid residue holding tank; the sprayer is connected to the dissolving solution circulation line via a hose; the secondary dissolving tank is connected to the centrifuge via the dissolving solution circulation line; valves are installed at the dissolving solution circulation line to the sprayer and at the centrifuge inlet;

[0011] The acid sludge holding tank containing sulfonate acid sludge is sent to the acid sludge holding tank platform. The acid sludge holding tank is lifted by a manual hoist and brought close to the side edge of the dissolving liquid mixing tank. The sprayer is fixed to the outer edge of the acid sludge holding tank.

[0012] Furthermore, the filter is a basket filter.

[0013] Furthermore, the solution prepared in step S2 consists of water, alkali, and a solvent;

[0014] The composition and mass percentage of the solvent are as follows: 15-20% water-soluble dispersant, 5-10% water-soluble antioxidant, 5-10% water-soluble imidazoline, 20-30% polyol, 30-55% deionized water, and 5-15% sodium carbonate.

[0015] Furthermore, the water-soluble dispersant is sodium hexametaphosphate; the water-soluble antioxidant is sodium bisulfite; and the polyol is glycerol.

[0016] Furthermore, in step S2, the acid sludge holding tank is made of 304 stainless steel and has a rectangular structure. The long side cross-section is a trapezoid with a wider top and narrower bottom, with a taper of 15°. One of the short sides is completely welded shut, while the other side is open to form a hinged opening. A matching movable baffle is made, and the upper edge of the movable baffle is fixed to the acid sludge holding tank with a shaft, so that it can be opened when tilting. When holding, it is tightened with quick-opening bolts to ensure no leakage. A 40mm wide outer edge is made on the long side of the holding tank for fixing the spray cleaning pipe rack.

[0017] Furthermore, the sprayer in step S2 includes several spray pipes and a pipe frame, with the lower part of the pipe frame connected to the spray pipes arranged in parallel; each spray pipe has three rows of φ5mm holes at its bottom, with the sprayed liquid from the holes spaced at 15° intervals and evenly distributed, and the blind end is plugged.

[0018] Furthermore, in step S3, when the liquid level in the secondary dissolving tank reaches 20%, the dissolving liquid circulation pump is turned on to establish circulation between the primary and secondary dissolving tanks.

[0019] Furthermore, in step S4, the agitator in the primary dissolving tank is turned on and stirred for 1.5 to 2 hours to ensure that the acid residue is fully dissolved, and then the mixture containing the dissolved acid residue is obtained.

[0020] Furthermore, the liquid phase collected in the intermediate tank after centrifugation in step S5 is recycled back into the petroleum sulfonate product at a rate of 3% to 5% (wt) to form the recycled petroleum sulfonate final product.

[0021] The centrifuge is a horizontal screw centrifuge; it can process and separate acid residue with particles smaller than φ10mm from the solution.

[0022] Compared with the above-mentioned background technology, the present invention has the following beneficial effects:

[0023] 1. This method features simple production process and stable product quality control.

[0024] 2. This method can recover the effective components in the acid residue, reduce the production cost of petroleum sulfonates, and realize the clean production of petroleum sulfonate plants.

[0025] 3. After dissolving the acid sludge using this method, the resulting mixture can be separated using a centrifuge. The separated solid phase, after drying, yields an odorless solid, and the acid sludge recovery rate is ≥85% (g / g).

[0026] 4. The final product is obtained by centrifugation after the mixture is fully dissolved to remove insoluble matter. This product can be recycled back into the production of petroleum sulfonate products by our company at a ratio of 3% to 5% (wt). The recycled petroleum sulfonate products meet the standard requirements and have an oil displacement efficiency of more than 26%.

[0027] 5. The product quality indicators after the acid residue solution and petroleum sulfonate are back-blended meet the standard of "QSY QL0145-2020 Petroleum Sulfonate for Enhanced Oil Recovery".

[0028] 6. Analysis shows that the soluble matter in the acid sludge is as high as 89%. Therefore, after dissolving it with a high-efficiency solvent, the effective components can be recovered quickly and efficiently using the method of this invention. The separated insoluble components can be treated as general solid waste, thus achieving the harmless treatment of the acid sludge. Attached image description:

[0029] Appendix Figure 1 This is a flowchart of the method for harmlessly treating waste acid residue from a petroleum sulfonate plant according to the present invention. Detailed implementation method:

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0031] like Figure 1 As shown, the present invention discloses a method for harmlessly treating waste acid residue from a petroleum sulfonate plant, comprising the following steps:

[0032] S1. After the preparation work is completed, prepare the dissolving solution; transport the prepared dissolving solution to the primary dissolving tank through the dissolving solution delivery pump; maintain the temperature at 60-70℃; the primary dissolving tank is connected to the secondary dissolving tank through an intermediate pipeline; the intermediate pipeline is connected to a filter; the filter is a basket filter.

[0033] The preparatory work includes: connecting the waste acid residue harmless treatment system of the petroleum sulfonate unit, the system including a dissolving solution preparation tank, which is connected to the feed lines for solvent, water and alkali; the outlet of the dissolving solution preparation tank is connected to a primary dissolving tank via a dissolving solution transfer pump; the primary dissolving tank is equipped with a stirrer; the primary dissolving tank is connected to a secondary dissolving tank via an intermediate pipeline; a filter is connected to the intermediate pipeline; the outlet of the secondary dissolving tank is connected to a sprayer, the primary dissolving tank and a centrifuge via a dissolving solution circulation line; a dissolving solution circulation pump is connected to the dissolving solution circulation line; an acid residue holding tank is placed at the feed port of the primary dissolving tank, and a sprayer is fixed above the acid residue holding tank; the sprayer is connected to the dissolving solution circulation line via a hose; the secondary dissolving tank is connected to the centrifuge via the dissolving solution circulation line; valves are installed at the dissolving solution circulation line to the sprayer and at the centrifuge inlet.

[0034] The acid sludge holding tank containing sulfonate acid sludge is sent to the acid sludge holding tank platform. The acid sludge holding tank is lifted by a manual hoist and brought close to the side edge of the dissolving liquid mixing tank. The sprayer is fixed to the outer edge of the acid sludge holding tank.

[0035] S2. Place the acid residue holding tank near the feed port of the primary dissolving tank, and fix the sprayer above the acid residue holding tank; connect the sprayer to the dissolving liquid circulation line with a hose;

[0036] The prepared solution consists of water, alkali and solvent;

[0037] The composition and mass percentage of the solvent are as follows: 15-20% water-soluble dispersant, 5-10% water-soluble antioxidant, 5-10% water-soluble imidazoline, 20-30% polyol, 30-55% deionized water, and 5-15% sodium carbonate. The water-soluble dispersant is sodium hexametaphosphate; the water-soluble antioxidant is sodium bisulfite; and the polyol is glycerol.

[0038] The acid sludge holding tank in step S2 is made of 304 stainless steel and has a rectangular structure. The long side cross-section is a trapezoid with a wider top and narrower bottom, with a taper of 15°. One of the short sides is completely welded shut, while the other side is open. A matching movable baffle is made, and the upper edge of the movable baffle is fixed to the acid sludge holding tank with a shaft, so that it can be opened when tilting. Quick-release bolts are used to tighten it during filling to ensure no leakage. A 40mm wide outer edge is made on the long side of the holding tank for fixing the spray cleaning pipe rack.

[0039] The sprayer in step S2 includes several spray pipes and a pipe frame. The lower part of the pipe frame is connected to the spray pipes arranged in parallel. There are 3 spray pipes. Each spray pipe has three rows of φ5mm holes at the bottom. The spray liquid from the holes is spaced at 15° intervals and evenly distributed. The blind end is plugged.

[0040] S3. Open the bottom valve of the primary dissolving tank to allow the solution in the primary dissolving tank to flow into the secondary dissolving tank by gravity through the intermediate pipeline. When the liquid level in the secondary dissolving tank reaches 20%, turn on the solution circulation pump to establish a circulation between the primary and secondary dissolving tanks.

[0041] S4. After the solution has circulated and stabilized in the primary and secondary dissolving tanks, open the feed port of the primary dissolving tank, tilt the acid sludge holding tank, and simultaneously open the valve of the solution circulation line leading to the spray pipe, allowing the solution to flow out through the spray pipe to flush the acid sludge in the holding tank. Gradually increase the tilt angle of the acid sludge holding tank and slowly add the dissolved, soft acid sludge into the primary dissolving tank. After adding the sludge, close the spray pipe valve and the feed port; turn on the agitator in the primary dissolving tank and stir for 1.5 to 2 hours to ensure that the acid sludge is fully dissolved, thus obtaining a mixed solution of dissolved acid sludge.

[0042] S5. The secondary dissolving tank is connected to the centrifuge via a dissolving liquid circulation line. Opening the valve at the centrifuge inlet of the dissolving liquid circulation line will transport the mixture of dissolved acid residue circulating in the dissolving tank to the centrifuge for separation. The insoluble matter is collected in a bucket at the centrifuge outlet. After separation by the centrifuge, the liquid phase enters the intermediate dissolving liquid tank for collection.

[0043] The liquid phase collected in the intermediate tank after centrifugation in step S5 is recycled back into the petroleum sulfonate product at a rate of 3% to 5% (wt) to form the recycled petroleum sulfonate final product. The centrifuge is a horizontal screw centrifuge, which can process and separate the solution of acid slag particles smaller than φ10mm.

[0044] Example 1:

[0045] 1. Add 1000 kg of fresh water, 105 kg of 36% sodium hydroxide, and 11.3 kg of proprietary solvent to the solution preparation tank. Maintain the temperature of the preparation tank at 60-70°C and stir for 1.5-2 hours. Use a solution transfer pump to transfer all the solution to the primary solution tank, maintaining the temperature at 60-70°C, and set aside for use.

[0046] 2. Use a forklift to transport the acid residue holding tank to the acid residue holding tank platform. Use a manual hoist to lift the acid residue holding tank so that it is close to the side edge of the primary dissolving liquid feed port. Then fix the spray pipe above the tank and connect the spray pipe to the dissolving liquid circulation line with a hose.

[0047] 3. Open the bottom valve of the primary dissolving tank, allowing the solution for dissolving the acid sludge in the primary dissolving tank to flow by gravity through the basket filter into the secondary dissolving tank. When the liquid level in the secondary dissolving tank reaches 20%, turn on the dissolving solution circulation pump to establish circulation between the primary and secondary dissolving tanks. After the circulation stabilizes, open the feed port of the primary dissolving tank. Use a manual hoist to tilt the acid sludge holding tank, and simultaneously open the valve connecting the dissolving solution circulation line to the spray pipe, allowing the dissolving solution to continuously flow out through the spray pipe to flush the acid sludge. Gradually increase the tilt angle of the acid sludge holding tank and slowly add dissolved, soft acid sludge into the primary dissolving tank. After adding the sludge, close the spray pipe valve and the feed port. Turn on the agitator in the primary dissolving tank and stir for 1.5 to 2 hours to ensure the acid sludge is fully dissolved.

[0048] 4. Slowly open the circulating liquid line to the centrifuge inlet valve, adjust the valve opening to ensure that the dissolved liquid part circulates in the dissolving tank and enters the centrifuge for separation. After passing through the centrifuge, the separated solid insoluble matter is collected in a bucket at the centrifuge slag outlet. The liquid phase after removing the insoluble matter enters the collection tank through the centrifuge liquid outlet and is recycled back into the petroleum sulfonate product at 5% (wt) to form the final product.

[0049] The testing indicators for petroleum sulfonate products are shown in Table 1 below:

[0050] Table 1

[0051]

[0052] The parameters and methods for testing and evaluating the product obtained in Example 1 are as follows:

[0053] 1. Interfacial tension: The rotating drop method according to enterprise standard Q / SY QL0145-2020 was adopted. The test temperature was 45℃, and the rotation speed was 3000r / min~5000r / min. The interfacial tension between the surfactant system and the target block crude oil was measured, and the data was recorded every 10 minutes. The entire measurement time was 120 minutes.

[0054] 2. Determination of active ingredients: Based on the different solubilities of active ingredients and unsulfonated oil in isopropanol and n-pentane in petroleum sulfonate products, the active ingredients and unsulfonated oil in petroleum sulfonate products are separated by extraction, and then dried in an oven to determine the content of active ingredients in petroleum sulfonate products.

[0055] 3. Core flooding test scheme: 0.3PV ternary composite flooding (1.2% weak base sodium carbonate + polymer 1440mg / L + 0.3% petroleum sulfonate final product, 40mPa·s) + 0.2PV polymer flooding (40mPa·s) + subsequent water flooding. The test results of the petroleum sulfonate product after re-blending are shown in Table 2.

[0056] Table 2

[0057]

[0058]

Claims

1. A method for the harmless treatment of waste acid residue from a petroleum sulfonate plant, characterized in that: Includes the following steps: S1. After the preparation work is completed, prepare the dissolving solution; transport the prepared dissolving solution to the primary dissolving tank through the dissolving solution delivery pump; maintain the temperature at 60~70℃; the primary dissolving tank is connected to the secondary dissolving tank through an intermediate pipeline; the outlet of the secondary dissolving tank is connected to the dissolving solution circulation line; S2. Place the acid residue holding tank near the feed port of the primary dissolving tank, and fix the sprayer above the acid residue holding tank; connect the sprayer to the dissolving liquid circulation line with a hose; The prepared solution consists of water, alkali, and solvent; The solvent consists of: water-soluble dispersant, water-soluble antioxidant, water-soluble imidazoline, polyol, deionized water, and sodium carbonate. The water-soluble dispersant is sodium hexametaphosphate; the water-soluble antioxidant is sodium bisulfite; and the polyol is glycerol. S3. Open the bottom valve of the primary dissolving tank to allow the solution in the primary dissolving tank to flow into the secondary dissolving tank by gravity through the intermediate pipeline. When the secondary dissolving tank reaches a certain level, turn on the solution circulation pump to establish a circulation between the primary and secondary dissolving tanks. S4. After the solution has circulated and stabilized in the primary and secondary dissolving tanks, open the feed port of the primary dissolving tank, tilt the acid sludge holding tank, and simultaneously open the valve of the solution circulation line leading to the spray pipe, allowing the solution to flow out through the spray pipe to flush the acid sludge in the acid sludge holding tank. Gradually increase the tilt angle of the acid sludge holding tank and slowly add the dissolved, soft acid sludge into the primary dissolving tank. After the sludge is added, close the spray pipe valve and the feed port; turn on the agitator in the primary dissolving tank to stir, ensuring that the acid sludge is fully dissolved to obtain a mixed solution of dissolved acid sludge. S5. The secondary dissolving tank is connected to the centrifuge via a dissolving liquid circulation line. Opening the valve at the centrifuge inlet of the dissolving liquid circulation line will transport the mixture of dissolved acid residue circulating in the dissolving tank to the centrifuge for separation. The insoluble matter is collected in a bucket at the centrifuge outlet. After separation by the centrifuge, the liquid phase enters the intermediate dissolving liquid tank for collection.

2. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 1, characterized in that: Step S1 preparation includes: connecting the waste acid residue harmless treatment system of the petroleum sulfonate unit, the system including a dissolving solution preparation tank, which is connected to the feed lines for solvent, water and alkali; the outlet of the dissolving solution preparation tank is connected to a primary dissolving tank via a dissolving solution transfer pump; the primary dissolving tank is equipped with a stirrer; the primary dissolving tank is connected to a secondary dissolving tank via an intermediate pipeline; a filter is connected to the intermediate pipeline; the outlet of the secondary dissolving tank is connected to a sprayer, the primary dissolving tank and a centrifuge via a dissolving solution circulation line; a dissolving solution circulation pump is connected to the dissolving solution circulation line; an acid residue collection tank is placed at the feed port of the primary dissolving tank, and a sprayer is fixed above the acid residue collection tank; the sprayer is connected to the dissolving solution circulation line via a hose; the secondary dissolving tank is connected to the centrifuge via the dissolving solution circulation line; valves are installed at the dissolving solution circulation line from the sprayer and at the centrifuge inlet; The acid sludge holding tank containing sulfonate acid sludge is sent to the acid sludge holding tank platform. The acid sludge holding tank is lifted by a manual hoist and brought close to the side edge of the dissolving liquid mixing tank. The sprayer is fixed to the outer edge of the acid sludge holding tank.

3. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 2, characterized in that: The filter is a basket filter.

4. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 1, characterized in that: The acid sludge holding tank in step S2 is made of 304 stainless steel and has a rectangular structure. The long side cross-section is a trapezoid with a wider top and narrower bottom, with a taper of 15°. One of the short sides is completely welded shut, while the other side is open. A matching movable baffle is made, and the upper edge of the movable baffle is fixed to the acid sludge holding tank with a shaft, so that it can be opened when tilting. Quick-release bolts are used to tighten it during filling to ensure no leakage. A 40mm wide outer edge is made on the long side of the holding tank for fixing the spray cleaning pipe rack.

5. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 4, characterized in that: The S2 sprayer includes several spray pipes and a pipe frame. The lower part of the pipe frame is connected to the spray pipes arranged in parallel. Each spray pipe has three rows of φ5mm holes at the bottom. The spray liquid from the holes is spaced at 15° intervals and evenly distributed. The blind end is plugged.

6. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 1, characterized in that: When the liquid level in the secondary dissolving tank reaches 20% in step S3, the dissolving liquid circulation pump is turned on to establish circulation between the primary and secondary dissolving tanks.

7. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 1, characterized in that: In step S4, the agitator in the primary dissolving tank is turned on and stirred for 1.5 to 2 hours to ensure that the acid residue is fully dissolved. The mixture containing the dissolved acid residue is then stirred to obtain a solution.

8. The method for harmless treatment of waste acid residue from a petroleum sulfonate plant according to claim 1, characterized in that: The liquid phase collected in the intermediate tank after centrifugation in step S5 is recycled back into the petroleum sulfonate product at a rate of 3% to 5% wt to form the recycled petroleum sulfonate final product; the centrifuge is a horizontal screw centrifuge; The solution containing acid residue particles smaller than φ10mm is processed and separated.

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