A method for treating refinery three sludge

Abstract

The application discloses a treatment method of refinery three sludge. The treatment method comprises the following steps: treating the oil sludge by using the slag as a drying agent to obtain three sludge coke, mixing the three sludge coke and fuel to be combusted as fuel of a CFB boiler, and the slag is the substance after the three sludge coke and fuel are combusted in the CFB boiler. The slag after the three sludge coke and fuel are combusted in the CFB boiler is recycled to realize the harmless treatment of the three sludge. On one hand, the unreacted calcium oxide in the slag can be used as a supplementary desulfurizer to reduce the sulfur content of the subsequent fuel combustion gas and reduce environmental pollution. On the other hand, the low water content, large particle size and good water absorption performance of the slag can reduce the water content and viscosity of the three sludge coke, and solve the problem of blockage of the boiler feeder and the discharge pipe. Finally, the slag contains 4%-8% unburned carbon, which can be recycled as fuel supplement to reduce the use amount of additional fuel, further reduce the carbon content of the slag, improve the recovery rate of the slag and save the cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of three sludge treatment, and particularly relates to a treatment method of three sludge in a refinery. BACKGROUND

[0002] At present, the main methods for treating three sludge in a refinery at home and abroad include incineration treatment, biological treatment, solvent extraction method, chemical hot washing treatment, coking treatment, and fuelization of three sludge. Indonesia has developed a synergistic incineration treatment technology, the most important feature of which is different from ordinary incineration. The highest temperature of ordinary incineration is 800℃, and the remaining ash after combustion must be treated as a hazardous waste. The highest temperature of the synergistic incineration treatment technology is 1500℃, and the remaining ash is very little and can be directly used as a raw material for cement. Harbin Institute of Technology and Shanghai Jiaotong University have proposed a new incineration technology: using the heterogeneous density circulating fluidized bed combustion technology to treat oily sludge. This method can directly send the sludge to the incinerator, without drying, combustion supporting, etc., greatly simplifying the treatment process and saving the treatment cost. The material in the fluidized bed moves violently, and the gas phase and solid phase are uniformly mixed, so that the oily sludge can be well burned in the circulating fluidized bed combustion chamber.

[0003] Biological treatment refers to using microorganisms to assimilate and degrade petroleum hydrocarbons in oily sludge as a carbon source, which is a natural process of strengthening, and a process of converting petroleum hydrocarbons into inorganic substances (H2O and CO2). Biological treatment has less impact on the environment and lower cost, and the cost is about 1 / 3-1 / 4 of the cost of incineration treatment. At present, the latest research on biological treatment technology in China also involves biological flotation and biological flocculants, which shows that biological treatment of oily sludge has a broad development prospect. Hans Pieper GmbH & Co. KG in Germany has a commercial sludge anaerobic treatment-digestion gas utilization technology, which uses sludge anaerobic fermentation to produce biogas for heating and power generation.

[0004] The Navajo Refining Company in the United States injects three sludge scum into the quenching oil slurry of the fractionating column of the catalytic cracking device, so that most of the scum finally enters the fuel oil. A method for recovering oil from oily sludge is disclosed in US 4990237. The Norwegian Petroleum Company and a Norwegian investor cooperated to develop the "Term Tech" process, but the treatment cost is relatively high.

[0005] The oil sludge, limestone and petroleum coke are mixed according to a certain proportion to process into three-mud coke, which is a means for treating oil sludge in Guangzhou Petrochemical Guangshi Logistics Three-mud Mixing Plant. According to the actual situation, the formula has obvious effect on treating dry three-mud, such as waste white clay, activated carbon, waste filler and waste resin, and the processed three-mud coke meets the requirements of CFB boiler blending combustion. However, for some oil sludge that has not been dewatered or filtered, such as Lipo tank oil sludge and north-south adjustment pool oil sludge, problems occur after processing. The blockage of CFB boiler feeding machine and discharge pipe is significantly aggravated, and the production and safe and environmental protection operation are seriously threatened. Although subsequent continuous research, formula proportion and receiving standard are developed, and the on-site processing environment is improved, the effect is still not obvious. With the start of the pool cleaning work of the branch, the contradiction between the pool cleaning task of the branch and the safe and environmental protection operation of the CFB boiler focuses on the three-mud coke. Especially after the transformation of the closed coke removal of the three coking devices, the appearance of the produced petroleum coke is relatively powder, and the particle size is fine, which makes the finished three-mud coke not meet the receiving standard after being used for mixing three-mud coke. Other units in the same industry treat three-mud according to this method, but due to the use of limestone as mixing raw material, the stickiness of the finished three-mud coke is increased under the condition of fine coke powder or three-mud particle size, which leads to serious blockage of the boiler feeding machine and the discharge pipe. Secondly, due to a large amount of limestone in the three-mud coke, the SO2 fluctuation of the flue gas is large when the three-mud coke mixed by limestone is blended, and the production adjustment is not timely, which easily leads to environmental protection early warning. Currently, wood chips are also used for three-mud mixing, but the cost is high and it is difficult to apply to continuous production. SUMMARY

[0006] The present application aims at the deficiencies of the prior art and provides a treatment method of refinery three-mud.

[0007] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0008] A treatment method of refinery three-mud, comprising the following steps: using slag as a drying agent to treat oil sludge to obtain three-mud coke, and mixing the three-mud coke and fuel as fuel for CFB boiler combustion; the slag is the substance after the three-mud coke and fuel are combusted in the CFB boiler.

[0009] The present application uses slag instead of traditional limestone or wood chips, firstly, the slag contains calcium oxide, which can be used as a supplementary desulfurizer, on the one hand, reducing the sulfur content of the subsequent combustion gas as fuel, reducing environmental pollution; on the other hand, in order to reduce the sulfur content of the combustion gas, the slag can be used as a supplementary desulfurizer to reduce the use of additional desulfurizer; secondly, the water content of the slag is close to 0, and the water absorption performance is good, which is beneficial to reduce the water content and viscosity of the three mud coke, and solves the problem of blocking of the boiler feeder and the discharge pipe; finally, the slag contains 4%-8% unburned carbon, which can be recycled and used as fuel supplement, reducing the use of additional fuel, and further reducing the carbon content of the slag, improving the recovery rate of the slag, and saving costs. In addition, the content of f-CaO(%) in the slag is about 10%, which can be recycled and utilized, therefore, the present application uses slag to treat three mud, which can reduce the use of drying agent and reduce costs. Moreover, compared with limestone and wood chips, the cost of slag is about 1 / 20 of the cost of limestone and about 1 / 300 of the cost of wood chips, so using slag instead of limestone or wood chips can save costs and is suitable for large-scale refinery three mud treatment.

[0010] Finally, the slag described in the present application is the material after the three mud coke and fuel are burned in the CFB boiler, which not only solves the problem of stacking and paying a large amount of cost for treating the slag in actual production, but also recycles and utilizes the slag, saves costs, and is green and environmentally friendly.

[0011] As a preferred embodiment of the present application, the slag contains the following mass percentage of slag: 78% 0.15mm≤slag fineness<1mm slag, 20% slag fineness<0.15mm slag.

[0012] In the prior art, limestone is used to treat three mud, and the limestone contains the following mass percentage of limestone: 100% 0.15mm≤slag fineness<1mm slag, 80% slag fineness<0.15mm slag. The particle size of the slag described in the present application is larger than that of limestone, which is beneficial to reduce the water content and viscosity of the three mud coke, and solves the problem of blocking of the boiler feeder and the discharge pipe, and the large particle size of the slag solves the problem of dust pollution compared with limestone.

[0013] As a preferred embodiment of the present application, the treatment method of refinery three mud includes the following specific steps:

[0014] (1) mixing and stirring the slag, petroleum coke and oil sludge to obtain three mud coke,

[0015] (2) mixing the three mud coke and fuel as fuel for CFB boiler and burning.

[0016] The treatment method of refinery three mud described in the present application is simple, easy to operate, and suitable for large-scale industrialization.

[0017] As a preferred embodiment of the present application, the mass ratio of the oil sludge, petroleum coke and slag is oil sludge: petroleum coke: slag = 1:13:3-5.

[0018] When the oil sludge, petroleum coke and slag are in the above ratio, the viscosity and moisture content of the three-mud coke are low, meeting the CFB combustion standard, and no harmful gas is generated when the fuel is combusted in a CFB boiler. If the content of the slag is too high, the combustion heat value of the CFB boiler combustion is reduced; if the content of the slag is too low, the viscosity and moisture content of the three-mud coke are affected, and the desulfurization effect is also affected.

[0019] More preferably, the mass ratio of the oil sludge, petroleum coke and slag is oil sludge: petroleum coke: slag = 1:13:4.

[0020] Through a large number of experimental explorations of the present applicant, when the oil sludge, petroleum coke and slag are in the above ratio, the viscosity and moisture content of the three-mud coke are the lowest, meeting the CFB combustion standard, and no harmful gas is generated when the fuel is combusted in a CFB boiler.

[0021] As a preferred embodiment of the present application, the mass ratio of the three-mud coke and the fuel is 2-4:6-8.

[0022] The fuel includes coal, biomass fuel, petroleum coke and self-produced coke, but is not limited to the above fuel types.

[0023] The slag contains 4%-8% unburned carbon, which can be used as fuel, reducing the use of additional fuel, also reducing the carbon content of the slag, improving the recovery rate of the slag and saving costs.

[0024] As a preferred embodiment of the present application, the stirring time is 7-9 hours.

[0025] As a preferred embodiment of the present application, in step (2), the temperature for mixing the three-mud coke and the fuel as the fuel for the CFB boiler combustion is 830-950℃.

[0026] Compared with the prior art, the present application has the following beneficial effects: the slag after the combustion of the three-mud coke and the fuel in a CFB boiler is recovered, and the three-mud is harmlessly treated. First, the slag contains calcium oxide, which can be used as a desulfurizing agent to reduce the sulfur content of the gas combusted as fuel subsequently, and reduce environmental pollution. Second, the water content of the slag is close to 0, and the particle is coarser than limestone, having good water absorption performance, which is conducive to reducing the water content and viscosity of the three-mud coke, and solving the problem of blockage of the boiler feeder. Finally, the slag contains 4%-8% unburned carbon, which can be recycled as fuel, reducing the use amount of additional fuel, further reducing the carbon content of the slag, improving the recovery rate of the slag and saving costs. DETAILED DESCRIPTION

[0027] For better illustrating the purpose, technical scheme and advantages of the present application, the present application will be further described in combination with specific examples.

[0028] The slag in the examples 1-4 and comparative examples 4-5 of the present application contains the following mass percentage of slag: 78% of slag with a fineness of 0.15mm≤slag fineness<1mm, 20% of slag with a fineness of <0.15mm.

[0029] Example 1

[0030] The specific steps of the example of the method for treating refinery three sludge according to the present application are as follows:

[0031] (1) 4 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0032] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully-closed coal feeder and sent to a pre-furnace air seed coal machine, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0033] Example 2

[0034] The specific steps of the example of the method for treating refinery three sludge according to the present application are as follows:

[0035] (1) 3 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0036] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully-closed coal feeder and sent to a pre-furnace air seed coal machine, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0037] Example 3

[0038] The specific steps of the example of the method for treating refinery three sludge according to the present application are as follows:

[0039] (1) 5 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0040] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully-closed coal feeder and sent to a pre-furnace air seed coal machine, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0041] Example 4

[0042] The specific steps of the embodiment of the method for treating refinery three sludge according to the present application are as follows:

[0043] (1) 4.5 parts by weight of slag, 13 parts by weight of petroleum coke, and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0044] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully enclosed coal feeder and sent to a pre-furnace air coal spreader, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0045] Comparative Example 1

[0046] The specific steps of the comparative example of the method for treating refinery three sludge according to the present application are as follows:

[0047] (1) 5 parts by weight of limestone, 13 parts by weight of petroleum coke, and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0048] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully enclosed coal feeder and sent to a pre-furnace air coal spreader, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0049] Comparative Example 2

[0050] The specific steps of the comparative example of the method for treating refinery three sludge according to the present application are as follows:

[0051] (1) 5 parts by weight of wood chips, 13 parts by weight of petroleum coke, and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0052] (2) The three sludge coke and the petroleum coke are mixed and transported by a grab bucket in a mass ratio of 3:7 through a belt to a pre-furnace bin, and then metered by a weighing type fully enclosed coal feeder and sent to a pre-furnace air coal spreader, and then sent by air to a CFB boiler with a furnace temperature of 830-950℃ for combustion, and the gas and solid after combustion are collected.

[0053] Comparative Example 3

[0054] The specific steps of the comparative example of the method for treating refinery three sludge according to the present application are as follows:

[0055] (1) 5 parts by weight of desulfurization ash, 13 parts by weight of petroleum coke, and 1 part by weight of oil sludge are stirred and mixed to obtain three sludge coke,

[0056] (2) the three-mud coke and the petroleum coke are mixed and transported by a grab according to a mass ratio of 3:7 through a belt to a pre-furnace bin, and then after metering by a weighing type fully-closed coal feeder, are sent into a pre-furnace wind coal sowing machine, and are sent into a CFB boiler by the wind to burn at a temperature of 830-950℃ in a furnace chamber, and the gas and solid after burning are collected.

[0057] Comparative Example 4

[0058] The specific steps of the comparative example of the treatment method of the refinery three mud according to the present application are as follows:

[0059] (1) 2 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three-mud coke,

[0060] (2) the three-mud coke and the petroleum coke are mixed and transported by a grab according to a mass ratio of 3:7 through a belt to a pre-furnace bin, and then after metering by a weighing type fully-closed coal feeder, are sent into a pre-furnace wind coal sowing machine, and are sent into a CFB boiler by the wind to burn at a temperature of 830-950℃ in a furnace chamber, and the gas and solid after burning are collected.

[0061] Comparative Example 5

[0062] The specific steps of the comparative example of the treatment method of the refinery three mud according to the present application are as follows:

[0063] (1) 6 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three-mud coke,

[0064] (2) the three-mud coke and the petroleum coke are mixed and transported by a grab according to a mass ratio of 3:7 through a belt to a pre-furnace bin, and then after metering by a weighing type fully-closed coal feeder, are sent into a pre-furnace wind coal sowing machine, and are sent into a CFB boiler by the wind to burn at a temperature of 830-950℃ in a furnace chamber, and the gas and solid after burning are collected.

[0065] Comparative Example 6

[0066] The specific steps of the comparative example of the treatment method of the refinery three mud according to the present application are as follows:

[0067] (1) 4 parts by weight of slag, 13 parts by weight of petroleum coke and 1 part by weight of oil sludge are stirred and mixed to obtain three-mud coke,

[0068] (2) the three-mud coke and the petroleum coke are mixed and transported by a grab according to a mass ratio of 3:7 through a belt to a pre-furnace bin, and then after metering by a weighing type fully-closed coal feeder, are sent into a pre-furnace wind coal sowing machine, and are sent into a CFB boiler by the wind to burn at a temperature of 830-950℃ in a furnace chamber, and the gas and solid after burning are collected.

[0069] The slag contains 100% 0.15mm≤slag fineness<1mm of slag, and 80% slag fineness<0.15mm of slag.

[0070] Test Example 1

[0071] The viscosity and moisture content of the three-mud coke obtained in Examples 1-4 and Comparative Examples 1-6 were analyzed by appearance hand balling inspection and moisture analysis test.

[0072] Table 1: Viscosity and moisture content of three-mud coke obtained in Examples and Comparative Examples

[0073]

[0074] Compared with Comparative Examples 1-6, the viscosity and moisture content of the three-mud coke obtained in Examples 1-4 are better, which can solve the problem of blocking of the boiler feeder and the downpipe, save time and economic cost, and the treatment method of refinery three-mud disclosed in the application is suitable for large-scale refinery three-mud treatment.

[0075] Test Example 2

[0076] In this test example, the emission concentrations of sulfur dioxide, nitrogen oxides and dioxins in the gas after combustion of the three-mud coke and fuel as fuel in a CFB boiler with a furnace temperature of 830-950℃ were tested according to Examples 1-4 and Comparative Examples 1-6, and the values in Table 2 are the average values of three tests.

[0077] Table 2: Concentrations of each gas after combustion obtained in Examples and Comparative Examples

[0078]

[0079]

[0080] The emission of sulfur dioxide and nitrogen oxides after combustion of the three-mud coke obtained by the treatment method of refinery three-mud of the application meets the requirements of enterprise ultra-clean emission standards (sulfur dioxide≤35mg / Nm 3 ; nitrogen oxides≤30mg / Nm 3 ), and the emission of dioxins also meets the requirements of environmental protection emission.

[0081] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the application and not to limit the protection scope of the application. Although the application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the application.

Claims

1. A method for treating refinery three mud, characterized by, The method comprises the following steps: treating the oil sludge with slag as a drying agent to obtain three-mud coke, and mixing the three-mud coke and fuel to burn as fuel of a CFB boiler; the slag is the substance after the three-mud coke and fuel are burned in the CFB boiler; Specifically, the method comprises the following steps: (1) mixing the slag, petroleum coke and oil sludge in proportion to obtain three-mud coke, wherein the mass ratio of the oil sludge, petroleum coke and slag is oil sludge: petroleum coke: slag = 1:13:3-5; (2) mixing the three-mud coke and fuel to burn as fuel of a CFB boiler.

2. The method of treating refinery three mud according to claim 1, characterized in that, The mass ratio of the oil sludge, petroleum coke and slag is oil sludge: petroleum coke: slag = 1:13:

4.

3. The method of treating refinery three mud according to claim 1, characterized in that, The slag contains the following mass percentage of slag: 78% of slag with a fineness of 0.15mm≤slag fineness<1mm, and 20% of slag with a fineness of <0.15mm.

4. The method of treating refinery three mud according to claim 1, characterized in that, The mass ratio of the three-mud coke and fuel is 2-4:6-8.

5. The method of treating refinery three mud according to claim 1, characterized in that, In the step (1), the stirring time is 7-9 hours.

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