CN110237814B - Preparation method of activated carbon for treating ocean oil spill - Google Patents

Abstract

The invention discloses a preparation method of active carbon for treating ocean spilled oil, which is characterized in that a substance with a low carbon-hydrogen ratio is added in the preparation process of the active carbon, the substance with the low carbon-hydrogen ratio is liquefied by heat in the carbonization heating process and then is cracked into a light component and a heavy component, a pore channel is formed in the escape process of the light component, the heavy component is finally carbonized to block the pore channel, a closed hole is formed at the position of the original substance with the low carbon-hydrogen ratio, the closed holes are filled with gas to form an air bag of active carbon particles, so that the active carbon can float on the water surface, once oil leaks to the sea surface, the active carbon is scattered to the sea surface, oil leakage is absorbed by the characteristic of the active carbon that the adsorption capacity to organic matters is large, the active carbon is recovered after the absorption is finished, the oil and the carbon are separated, and the active carbon can be recycled after the regeneration activation. The active carbon prepared by the method has the advantages of large pore volume, large specific surface, strong adsorbability, large adsorption capacity and the like, and the preparation method is simple in preparation process and easy to operate.

Description

Preparation method of activated carbon for treating ocean oil spill

Technical Field

The invention relates to the technical field of activated carbon preparation, in particular to a preparation method of activated carbon for treating ocean oil spill.

Background

During the exploration, development, refining and transportation and storage of petroleum, crude oil or oil products leak from the operation site or reservoir to the ground, water surface, beach or sea surface due to accidents or misoperation, and simultaneously, a piece of oil film with different thicknesses is formed due to different oil components, which is called oil spill.

The oil spill source comprises crude oil, solvent oil fractionated from the crude oil, gasoline, kerosene, diesel oil, lubricating oil, paraffin, asphalt and various products formed by cracking and catalyzing. The amount of petroleum pollutants discharged into the ocean is about 1 million tons per year. The spilled oil is quickly expanded into a film on the surface of the sea under the action of gravity, inertia force, friction force and surface tension on the sea, and then is divided into block-shaped or strip-shaped oil films with different sizes under the action of wind waves and ocean currents, and the oil films drift and diffuse with the wind; a series of complex changes of petroleum body occur, including diffusion, evaporation, dissolution, emulsification, photochemical oxidation, microbial oxidation, sedimentation, formation of pitch balls, and transfer along food chains. Oil spills can be harmful to marine life and harm birds and humans.

After oil spill at sea, the currently used treatment methods include physical treatment methods, chemical methods and biological methods. The physical method is to eliminate the petroleum pollutants on the water surface by using a mechanical device. For example, the sewage disposal ship collects the spilled oil by using a recovery device on the ship; the oil containment boom is used for surrounding oil after the oil leaks to the sea surface, preventing the oil from spreading and then trying to recover the oil; magnetic separation is developed by one company in the United states and is characterized in that special magnetic liquid which is soluble in petroleum and insoluble in water is utilized, the special magnetic liquid is composed of magnetic particles with one thousandth of the diameter of human hair, and when the liquid is atomized on the water surface, floating petroleum can be absorbed and removed; the adsorption is that the oil absorption sponge invented in the United states and the oil absorption wool felt commonly used at present absorb oil stains. The chemical treatment method is to use chemical agents to remove oil stains, and to directly emulsify and disperse a thin oil film with the thickness of less than 1mm in seawater by changing the physical properties of spilled oil. The biological treatment method is to remove petroleum flowing into the sea by utilizing the strong oxidative degradation of petroleum by certain microorganisms naturally present in the sea. The problem of cleaning oil spillage is very important in all countries in the world, and unfortunately, an efficient countermeasure is always lacked.

The active carbon is a nonpolar molecule, has large adsorption capacity to organic matters, and is widely used in the aspects of toxic gas purification, waste gas treatment, sewage treatment, solvent recovery and the like. The sewage membrane biological treatment process disclosed in the Chinese patent CN101172704A and the method for removing antibiotic-sulfadiazine in water by using the activated carbon fiber adsorbent disclosed in the Chinese patent CN105948158A both utilize the characteristic of selective adsorption of organic matters of activated carbon to treat sewage. However, these activated carbons are not suitable for treating offshore spills due to their density being greater than that of seawater.

Disclosure of Invention

Aiming at the problems that the oil film causes serious marine pollution and the treatment lacks high-efficiency countermeasures, the invention provides a preparation method of activated carbon for adsorbing the marine oil film. The properties of the activated carbon obtained by the method are as follows: the pore volume is more than or equal to 0.75mL/g, the specific surface is more than or equal to 450m2/g, and the volume of the closed pores accounts for 20-35% of the total pore volume. The preparation method is simple and easy to operate.

The technical means adopted by the invention are as follows:

a preparation method of active carbon for treating ocean oil spill,

the method comprises the following steps:

step one, uniformly mixing coking coal and carbon-containing substances according to a proportion, and grinding into powder;

step two, putting the powder obtained in the step one, the extrusion aid, the low-carbon-hydrogen-ratio substance and water into a rolling machine according to a proportion, rolling and mixing;

step three, feeding the uniformly mixed material obtained in the step two into a plodder, and extruding and molding under pressure;

step four, putting the formed object obtained in the step three into a carbonization furnace for carbonization, and controlling the carbonization temperature and the carbonization time;

and step five, putting the materials obtained in the step four into an activation furnace, activating in a certain atmosphere, and controlling the activation temperature and the activation time to obtain the activated carbon.

Wherein:

step one, the carbonaceous substance comprises one or more of coke powder, raw coal, asphalt powder, bituminous coal, fruit shells, wood chips, petroleum coke, waste plastics and waste tires, and preferably coke powder; the mass ratio of the coking coal to the carbonaceous material is 1: 1-1: 5; the grinding mesh number of the powder is more than 200 meshes.

The extrusion aid in the second step is one or more of coal tar, heavy diesel oil, wax oil and residual oil, and preferably coal tar; the low-carbon-hydrogen-ratio substance is an organic substance which is easy to liquefy under heat, such as one or more of paraffin, petroleum resin, polyethylene glycol and the like; the mass ratio of the added powder, the extrusion aid, the low-carbon-hydrogen ratio substance and the water is as follows: extrusion aid: low carbon-hydrogen ratio substance: water 1: (0.35-0.5): (0.05-0.1): (0.07 to 0.17);

thirdly, the strip extrusion pressure of the strip press is 15-25 MPa; the shape is one of a cylinder, a clover shape and a clover shape, and the diameter is 2-10 mm;

step four, the carbonization atmosphere is carried out under the condition of inert gas, and the carbonization temperature is 400-600 ℃; the carbonization time is 30-120 min;

step five, introducing water vapor or CO2 when the activation atmosphere is activation; the activation temperature is 700-950 ℃; the activation time is 90-180 min.

In the invention, a low carbon-hydrogen ratio substance is added in the preparation process of the activated carbon, the low carbon-hydrogen ratio substance is liquefied by heat in the carbonization heating process and then is cracked into a light component and a heavy component, a pore channel is formed in the escape process of the light component, the heavy component is gradually heavy along with the continuous rise of the carbonization temperature, the pore channel is blocked by carbonization finally, and a closed hole is formed at the position of the original low carbon-hydrogen ratio substance; the active carbon prepared by the invention contains abundant open pores and closed pores in a certain proportion, the proportion of the closed pores is adjustable, the closed pores are filled with gas to form air bags of active carbon particles, the active carbon can float on the water surface, once petroleum leaks to the sea surface, the active carbon is firstly surrounded by an oil containment boom to prevent the diffusion of the petroleum, then the active carbon is scattered to the sea surface, oil leakage is absorbed by utilizing the characteristic of large adsorption capacity of the active carbon on organic matters, the active carbon is recovered after the absorption is finished to carry out oil-carbon separation, the separated oil is continuously subjected to a processing procedure or is directly used, and the active carbon can be recycled after regeneration and activation; the activated carbon prepared by the method has the advantages of large pore volume, large specific surface, strong adsorbability, large adsorbability and the like; the method has simple preparation process and easy operation.

In the invention, the specific surface area and the pore volume are measured by adopting a low-temperature liquid nitrogen adsorption method.

In the invention, the volume proportion of the closed pores is measured by the following method: firstly, preparing a to-be-detected carrier and a reference carrier, wherein the preparation of the reference carrier is the same as that of the carrier except that no substance with a low carbon-hydrogen ratio is added in the mixture ratio of the to-be-detected carrier and the reference carrier. Firstly, measuring the skeleton density of a control carrier, namely filling a 100mL measuring cylinder into the control carrier to 100mL scales, adding deionized water into the measuring cylinder to 100mL scales under the vacuum condition, wherein the volume of 100mL minus the volume of the added water is the volume of the 100mL control carrier skeleton, and the weight of 100mL control carrier divided by the volume of 100mL control carrier skeleton is the skeleton density of the control carrier; the solid parts of the carrier and the control carrier are considered to have the same degree of compactness, and the same skeleton density, the weight of the closed pores filled with the solid is obtained by subtracting the weight of 100mL of the carrier from the weight of 100mL of the control carrier, the weight is divided by the volume of the closed pores in the carrier with the skeleton density of 100mL, and the sum of the volume of the closed pores in the carrier with the volume of 100mL of the carrier with the closed pores and the pore volume of 100mL of the carrier with the skeleton density is the percentage of the volume of the closed pores in the carrier with the total pore volume.

The vectors of the present invention and the control vectors, although slightly different in preparation, are considered to be negligible differences in this part in the present invention.

Compared with the prior art, the invention has the following advantages:

1. the active carbon prepared by the method has large pore volume and large specific surface, and simultaneously contains certain closed pores which form air bags of active carbon particles and can lead the active carbon to float on the water surface.

2. The preparation method is simple and easy to operate.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. Any specific values in all examples shown and discussed herein are to be construed as exemplary only and not as limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The invention provides a preparation method of active carbon for treating ocean oil spill,

the method comprises the following steps:

step one, uniformly mixing coking coal and carbon-containing substances according to a proportion, and grinding into powder;

step two, putting the powder obtained in the step one, the extrusion aid, the low-carbon-hydrogen-ratio substance and water into a rolling machine according to a proportion, rolling and mixing;

step three, feeding the uniformly mixed material obtained in the step two into a plodder, and extruding and molding under pressure;

step four, putting the formed object obtained in the step three into a carbonization furnace for carbonization, and controlling the carbonization temperature and the carbonization time;

and step five, putting the materials obtained in the step four into an activation furnace, activating in a certain atmosphere, and controlling the activation temperature and the activation time to obtain the activated carbon.

Wherein:

step one, the carbonaceous substance comprises one or more of coke powder, raw coal, asphalt powder, bituminous coal, fruit shells, wood chips, petroleum coke, waste plastics and waste tires, and preferably coke powder; the mass ratio of the coking coal to the carbonaceous material is 1: 1-1: 5; the grinding mesh number of the powder is more than 200 meshes.

The extrusion aid in the second step is one or more of coal tar, heavy diesel oil, wax oil and residual oil, and preferably coal tar; the low-carbon-hydrogen-ratio substance is an organic substance which is easy to liquefy under heat, such as one or more of paraffin, petroleum resin, polyethylene glycol and the like; the mass ratio of the added powder, the extrusion aid, the low-carbon-hydrogen ratio substance and the water is as follows: extrusion aid: low carbon-hydrogen ratio substance: water 1: (0.35-0.5): (0.05-0.1): (0.07 to 0.17);

thirdly, the strip extrusion pressure of the strip press is 15-25 MPa; the shape is one of a cylinder, a clover shape and a clover shape, and the diameter is 2-10 mm;

step four, the carbonization atmosphere is carried out under the condition of inert gas, and the carbonization temperature is 400-600 ℃; the carbonization time is 30-120 min;

step five, introducing water vapor or CO2 when the activation atmosphere is activation; the activation temperature is 700-950 ℃; the activation time is 90-180 min.

The specific operation is that a certain amount of coking coal and carbon-containing substances are weighed, mixed evenly and ground into powder with a certain mesh number for standby. Putting the obtained powder into a rolling machine, adding a certain amount of extrusion aid, a low-carbon-hydrogen-ratio substance and a certain amount of water, starting the rolling machine to roll and mix, moving the material onto a plodder to perform extrusion molding after the materials are uniformly mixed and form blocks, ensuring that the extrusion pressure is 15-25 MPa, drying the extrusion molding material, then carbonizing the extrusion molding material in a carbonization furnace, controlling the carbonization temperature to be 400-600 ℃, carbonizing the carbonization time to be 30-120 min, putting the carbonized material into an activation furnace, activating in the atmosphere of water vapor or CO2, controlling the activation temperature to be 700-950 ℃, activating the activation time to be 90-180 min, and obtaining the activated carbon after activation.

Example 1

Mixing the coking coal and the coke powder according to the mass ratio of 1: 2, and grinding the mixture into powder of 300 meshes; weighing 1000g of the powder, adding the powder into a rolling machine, simultaneously adding 425g of coal tar, 60g of paraffin and 140g of water, and starting the rolling machine to roll and mix the materials; stopping rolling and mixing when the material is plastic, moving to a plodder, extruding under the pressure of 20MPa for molding, wherein the extruded strip is cylindrical and has the diameter of phi 8.0 mm; drying the formed material, then putting the dried material into a carbonization furnace, carbonizing the dried material under nitrogen, and controlling the carbonization temperature to be 550 ℃ and the carbonization time to be 50 min; cooling the carbonized material, introducing into an activation furnace, introducing water vapor at the activation temperature of 900 ℃, and controlling the activation time to be 100 min; and cooling after the activation is finished to obtain the active carbon. The properties of the obtained activated carbon a-1 are shown in Table 1.

Example 2

The preparation process was as in example 1 except that the coke powder was changed to husk, and the properties of the obtained activated carbon a-2 are shown in Table 1.

Example 3

The procedure was as in example 1 except that the paraffin was changed to a petroleum resin and the amount added was changed to 90g, and the properties of the obtained activated carbon a-3 were as shown in Table 1.

Example 4

The preparation process was as in example 1 except that the carbonization time was changed to 100min, and the properties of the obtained activated carbon a-4 are shown in Table 1.

Example 5

The preparation process is as in example 1, except that the activation atmosphere is changed to activation under the condition of CO2 gas, and the properties of the obtained activated carbon a-5 are shown in Table 1.

TABLE 1 Properties of the activated carbon prepared according to the invention

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (4)

1. A preparation method of active carbon for treating ocean oil spill is characterized in that,

the method comprises the following steps:

step one, uniformly mixing coking coal and carbon-containing substances according to a proportion, and grinding into powder;

step two, putting the powder obtained in the step one, the extrusion aid, the low-carbon-hydrogen-ratio substance and water into a rolling machine according to a proportion, rolling and mixing;

step three, feeding the uniformly mixed material obtained in the step two into a plodder, and extruding and molding under pressure;

step four, putting the formed object obtained in the step three into a carbonization furnace for carbonization, and controlling the carbonization temperature and the carbonization time;

step five, the materials obtained in the step four enter an activation furnace, and are activated in a certain atmosphere, the activation temperature and the activation time are controlled, and the activated carbon is obtained after activation;

the carbonaceous matter includes: one or more of coke powder, raw coal, asphalt powder, bituminous coal, fruit shells, wood chips, petroleum coke, waste plastics and waste tires;

the extrusion aid comprises: one or more of coal tar, heavy diesel oil, wax oil and residual oil;

the low-carbon-hydrogen ratio substances are as follows: organic matter that liquefies readily upon exposure to heat, including: one or more of paraffin, petroleum resin and polyethylene glycol;

the activation atmosphere is water vapor or CO introduced during activation₂(ii) a The activation temperature is 700-950 ℃; the activation time is 90-180 min;

the mass ratio of the powder, the extrusion aid, the low-carbon-hydrogen ratio substance and the water is as follows: extrusion aid: low carbon-hydrogen ratio substance: water = 1: (0.35-0.5): (0.05-0.1): (0.07-0.17).

2. The preparation method of the activated carbon for treating the marine oil spill as claimed in claim 1, wherein the activated carbon comprises the following components:

the strip extrusion pressure of the strip extrusion machine is 15-25 MPa; the shape is one of a cylinder, a clover shape and a clover shape, and the diameter is 2-10 mm.

3. The preparation method of the activated carbon for treating the marine oil spill as claimed in claim 1, wherein the activated carbon comprises the following components:

the carbonization atmosphere is carried out under the condition of inert gas, and the carbonization temperature is 400-600 ℃; the carbonization time is 30-120 min.

4. The method for preparing the activated carbon for treating marine oil spill according to claim 1 or 2, characterized in that:

the mass ratio of the coking coal to the carbonaceous material is 1: 1-1: 5; the grinding mesh number of the powder is more than 200 meshes.