CN110787782A - Regeneration method of white oil-containing waste alkaline clay - Google Patents

Abstract

The invention discloses a regeneration method of white oil-containing waste alkaline clay, which comprises the following steps: step 1, elution, namely mixing and stirring the waste alkaline argil containing white oil and an organic solvent, performing ultrasonic stirring in the mixing and stirring process, then performing solid-liquid separation, obtaining the argil after elution in a solid part, and obtaining the oil-containing solvent in a liquid part; step 2, drying, namely drying the eluted argil to obtain dried argil; and 3, screening, namely screening the dried argil through a double-layer screen, wherein the material between the double-layer screen is the product regenerated argil after screening. The invention does not use ethanol and water, uses ultrasonic waves to improve the regeneration speed and effect of the alkaline argil, and uses a vibrating screen to separate large particles and ultrafine particles so as to improve the decolorization rate of the recovered argil.

Description

Regeneration method of white oil-containing waste alkaline clay

Technical Field

The invention belongs to the technical field of resource recycling, and particularly relates to a regeneration method of white oil-containing waste alkaline clay.

Background

White oil is used as a pore-forming agent in the production of a lithium battery diaphragm, in the process flow, the used white oil is subjected to rectification, clay decoloration and deacidification and filtration processes and then returns to the production process for recycling, wherein alkaline clay mainly plays a role in decoloring and neutralizing acid substances in the white oil recovery process, and 2-5 wt% of alkaline clay is generally added in the white oil decoloration, so that a large amount of waste clay is generated every year.

Among the prior art processes for treating spent clay, the most effective clay regeneration is: the CN101434853A oil refining waste clay regeneration and recovery method adopts a mode of combining ethanol extraction with water washing, can elute the grease in the waste clay, but the process can reduce the pH value of the regenerated clay, influences the capability of neutralizing acid substances in white oil during the recovery and utilization, and is not suitable for the regeneration of alkaline clay.

In addition, the regenerated clay has the phenomenon of uneven particle size, agglomerated large particles and pulverized ultrafine particles are easy to appear in the regeneration process, and the existence of particles with overlarge and undersize particle sizes influences the decoloring effect and the filtering effect in the recycling process of the regenerated clay.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a method for regenerating waste alkaline clay containing white oil, which does not use ethanol and water, uses ultrasonic waves to improve the regeneration speed and effect of the alkaline clay, uses a vibrating screen to separate large particles and ultrafine particles and improves the decolorization rate of the recovered clay.

The invention is realized by the following technical scheme:

a regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, eluting, namely mixing and stirring the white oil-containing waste alkaline clay and an organic solvent, wherein the mass ratio of the organic solvent to the white oil-containing waste alkaline clay is 3-7: 1, ultrasonic stirring is adopted in the mixing and stirring process, the stirring time is 5-15 minutes, then solid-liquid separation is carried out, the solid part is the eluted clay, and the liquid part is the oil-containing solvent;

the organic solvent is dichloromethane;

step 2, drying, namely drying the eluted argil to obtain dried argil, wherein the drying temperature is 105-120 ℃, and the drying time is 20-40 minutes;

step 3, screening, namely screening the dried argil through a double-layer screen, wherein after screening, the material between the double-layer screen is the product regenerated argil; the aperture of the upper layer screen of the double-layer screen is 50-100 meshes, and the aperture of the lower layer screen is 350-400 meshes.

In the technical scheme, the ultrasonic stirring frequency in the step 1 is 20-40 kHz.

In the technical scheme, the ultrasonic stirring in the step 1 is realized by an ultrasonic vibrating rod with the frequency of 20-40 kHz.

In the technical scheme, a clay filter is used for solid-liquid separation in the step 1, and an automatic slag discharge filter is preferably used.

In the technical scheme, the step 1 is repeated for at least 1 time, when the step is repeated, the eluted argil obtained in the previous step 1 and an organic solvent are mixed and stirred, the mass ratio of the organic solvent to the white oil-containing waste alkaline argil is 3-7: 1, ultrasonic stirring is adopted in the mixing and stirring process, the stirring time is 5-15 minutes, then solid-liquid separation is carried out, the eluted argil is obtained from a solid part, and the oil-containing solvent is obtained from a liquid part; the organic solvent is dichloromethane.

In the above technical scheme, the drying process of step 2 is completed in a stainless steel double-cone dryer.

In the technical scheme, the method also comprises the oil-containing solvent treatment process, wherein the oil-containing solvent is rectified to obtain the waste white oil and the recovered organic solvent.

In the above technical scheme, in the step 3, the double-layer screen mesh is a vibrating screen, and preferably a double-layer rotary vibrating screen.

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, eluting, namely ultrasonically stirring white oil-containing waste alkaline clay and dichloromethane, wherein the mass ratio of the dichloromethane to the white oil-containing waste alkaline clay is 5:1, the ultrasonic stirring is completed by an ultrasonic vibration rod with the frequency of 28kHz, the stirring time is 10 minutes, then carrying out solid-liquid separation, obtaining the clay after primary elution on a solid part, and obtaining an oil-containing solvent on a liquid part;

step 2, ultrasonically stirring the clay subjected to the primary elution and dichloromethane in a mass ratio of 5:1, completing ultrasonic stirring by using an ultrasonic vibration rod with the frequency of 28kHz, performing solid-liquid separation, obtaining the clay subjected to the secondary elution from a solid part, and obtaining an oil-containing solvent from a liquid part, wherein the stirring time is 10 minutes;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

step 4, screening, namely screening the dried argil by a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes;

step 5, the oil-containing solvent treatment process is also included, the oil-containing solvent treatment process is to rectify the oil-containing solvent to obtain waste white oil and recycle dichloromethane, and the rectification process is as follows: feeding an oil-containing solvent into a rectifying tower kettle, wherein the temperature of the tower kettle is 80-90 ℃, the height of the tower is 11 m, the temperature of the top of the tower is lower than 45 ℃, the reflux ratio is 1.1, after the rectification is finished, stopping feeding and reflux, heating the tower kettle to 120-130 ℃, and extracting waste white oil from the tower kettle after one hour.

The invention has the advantages and beneficial effects that:

the invention relates to a regeneration method of spent alkaline clay containing white oil, which does not use ethanol and water, uses ultrasonic waves to improve the regeneration speed and effect of the alkaline clay, uses a vibrating screen to separate large particles and ultrafine particles, and improves the decolorization rate of the recovered clay. Compared with the scheme of adopting dichloroethane as a solvent in the prior art CN107185508, the dichloroethane is toxic and potentially carcinogenic, has the viscosity of 0.4983mPa & s (20 ℃), is lower than the dichloroethane in toxicity, has the viscosity of 0.43mPa & s (20 ℃), is lower than the dichloroethane in toxicity, and is more beneficial to extracting white oil.

The invention relates to a regeneration process of white oil-containing waste alkaline clay, which is characterized in that under the action of ultrasonic waves of 20-40 kHz, a polar solvent dichloromethane is used for replacing ethanol to extract waste white oil and absorb the waste white oil in the waste alkaline clay, the extraction temperature is normal temperature, solid-liquid separation is carried out, the alkaline clay is dried and screened to obtain the regenerated clay. As is clear from Table 1, the recovered alkaline clay has comparable decolorization rate and activity to fresh clay, and has a lower water content than fresh clay, and the pH of the alkaline clay recovered with methylene chloride (examples 1, 3 and 4) is lowered by 0.1 to 0.3 compared with fresh clay, while the pH of the alkaline clay recovered with ethanol (example 6) is lowered by 1.5.

Drawings

FIG. 1 is a schematic flow chart of a process for regenerating spent alkaline clay containing white oil.

For a person skilled in the art, other relevant figures can be obtained from the above figures without inventive effort.

Detailed Description

In order to make the technical solution of the present invention better understood, the technical solution of the present invention is further described below with reference to specific examples.

Example 1

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 500 kg of dichloromethane and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the dichloromethane to the waste alkaline clay is 5:1, an ultrasonic vibration rod with the use frequency of 28kHz is used for stirring for 10 minutes, the temperature is normal temperature, and then a clay filter is used for separating clay from a solvent; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely ultrasonically stirring the clay subjected to primary elution and dichloromethane, wherein the mass ratio of the dichloromethane to the clay subjected to primary elution is 5:1, the ultrasonic stirring is completed by an ultrasonic vibration rod with the frequency of 28kHz, the stirring time is 10 minutes, then performing solid-liquid separation, obtaining the clay subjected to secondary elution on a solid part, and obtaining an oil-containing solvent on a liquid part; solid-liquid separation adopts a clay filter manufacturer: mechanical parts of high clothes, model number: GLJ-20;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

screening, namely screening the dried argil by using a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening, and totally recovering 39.8 kg of the regenerated argil; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes; double-layer vibrating screen manufacturers: dahan vibration machines, Inc., model number, in New county, N.C.: DH-2000;

and 5, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

Example 2 (without using a sieving procedure)

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 500 kg of dichloromethane and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the dichloromethane to the waste alkaline clay is 5:1, an ultrasonic vibration rod with the use frequency of 28kHz is used for stirring for 10 minutes, the temperature is normal temperature, and then a clay filter is used for separating clay from a solvent; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely ultrasonically stirring the clay subjected to primary elution and dichloromethane, wherein the mass ratio of the dichloromethane to the clay subjected to primary elution is 7:1, the ultrasonic stirring is completed by an ultrasonic vibration rod with the frequency of 28kHz, the stirring time is 10 minutes, then performing solid-liquid separation, obtaining the clay subjected to secondary elution on a solid part, and obtaining an oil-containing solvent on a liquid part;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

and 4, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

Example 3

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 300 kg of dichloromethane and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the dichloromethane to the waste alkaline clay is 3:1, an ultrasonic vibration rod with the use frequency of 28kHz is used for stirring for 10 minutes, the temperature is normal temperature, and then a clay filter is used for separating clay and a solvent; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely performing ultrasonic stirring on the clay subjected to primary elution and dichloromethane, wherein the mass ratio of the dichloromethane to the clay subjected to primary elution is 3:1, the ultrasonic stirring is completed by an ultrasonic vibration rod with the frequency of 28hz, the stirring time is 10 minutes, then performing solid-liquid separation, obtaining the clay subjected to secondary elution on a solid part, and obtaining an oil-containing solvent on a liquid part;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

screening, namely screening the dried argil by using a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening, and totally recovering 39.9 kg of the regenerated argil; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes;

and 5, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

Example 4

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 500 kg of dichloromethane and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the dichloromethane to the waste alkaline clay is 5:1, an ultrasonic vibration rod with the use frequency of 20kHz is used for stirring for 5 minutes, the temperature is normal temperature, and then a clay filter is used for separating clay from a solvent; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely ultrasonically stirring the clay subjected to primary elution and dichloromethane, wherein the mass ratio of the dichloromethane to the clay subjected to primary elution is 5:1, completing ultrasonic stirring by using an ultrasonic vibration rod with the frequency of 20kHz, stirring for 5 minutes, then performing solid-liquid separation, obtaining the clay subjected to secondary elution from a solid part, and obtaining an oil-containing solvent from a liquid part;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 105 ℃, and the drying time is 30 minutes;

screening, namely screening the dried argil by using a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening, and totally recovering 39.6 kg of the regenerated argil; the aperture of the upper layer screen mesh of the double-layer screen mesh is 100 meshes, and the aperture of the lower layer screen mesh is 400 meshes;

and 5, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

Example 5 (without ultrasonic agitation)

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 500 kg of dichloromethane and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the dichloromethane to the waste alkaline clay is 5:1, stirring for 10 minutes at normal temperature, and then separating the clay and the solvent by using a clay filter; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely ultrasonically stirring the carclazyte subjected to the primary elution and dichloromethane, wherein the mass ratio of the dichloromethane to the carclazyte subjected to the primary elution is 5:1, the stirring time is 10 minutes, then performing solid-liquid separation, obtaining the carclazyte subjected to the secondary elution from a solid part, and obtaining an oil-containing solvent from a liquid part;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 120 ℃, and the drying time is 30 minutes;

screening, namely screening the dried argil by using a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening, and totally recovering 39.7 kg of the regenerated argil; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes;

and 5, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

Example 6 (using ethanol as solvent)

A regeneration method of white oil-containing waste alkaline clay comprises the following steps:

step 1, performing primary elution, mixing and stirring 500 kg of ethanol and 100 kg of waste alkaline clay containing white oil with the mass fraction of 40%, wherein the weight ratio of the ethanol to the waste alkaline clay is 5:1, an ultrasonic vibration rod with the use frequency of 28kHz is used for stirring for 10 minutes, the temperature is normal temperature, and then a clay filter is used for separating the clay and the solvent; obtaining the clay after the primary elution of the solid part and obtaining the oil-containing solvent of the liquid part;

step 2, performing secondary elution, namely ultrasonically stirring the clay subjected to primary elution and ethanol, wherein the mass ratio of the ethanol to the clay subjected to primary elution is 7:1, completing ultrasonic stirring by using an ultrasonic vibration rod with the frequency of 28kHz, stirring for 10 minutes, then performing solid-liquid separation, obtaining the clay subjected to secondary elution from a solid part, and obtaining an oil-containing solvent from a liquid part;

step 3, drying, namely drying the clay subjected to secondary elution by a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

screening, namely screening the dried argil by using a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening, and totally recovering 39.5 kg of regenerated argil; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes;

and 5, in the oil-containing solvent treatment process, rectifying the oil-containing solvent obtained by twice elution to obtain waste white oil and a recovered organic solvent.

TABLE 1 comparison of New and regenerated alkaline clays

The activity degree refers to the physical quantity of the adsorption capacity of the argil on colored substances and organic substances.

In example 6, ethanol is used for extraction, but the ethanol can dissolve a part of sodium hydroxide of the alkaline clay, so that the pH value of the alkaline clay is reduced; in the example 2, the bleaching rate and the activity of the recovered white clay are reduced due to the white clay with large particle size without screening; in example 5, the white oil in the alkaline clay could not be completely extracted without using ultrasonic wave in the same time, resulting in the decrease of the decolorization rate and activity of the recovered clay.

Relational terms such as "first" and "second," and the like, may be used solely to distinguish one element from another element having the same name, without necessarily requiring or implying any actual such relationship or order between such elements.

The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.

Claims (9)

1. A regeneration method of white oil-containing waste alkaline clay is characterized by comprising the following steps:

step 1, elution: mixing and stirring the white oil-containing waste alkaline clay and an organic solvent, wherein the mass ratio of the organic solvent to the white oil-containing waste alkaline clay is 3-7: 1, ultrasonic stirring is adopted in the mixing and stirring process, the stirring time is 5-15 minutes, then solid-liquid separation is carried out, the solid part is eluted clay, and the liquid part is eluted oil-containing solvent;

the organic solvent is dichloromethane;

and 2, drying: drying the eluted argil to obtain dried argil, wherein the drying temperature is 105-120 ℃, and the drying time is 20-40 minutes;

and step 3, screening: screening the dried argil through a double-layer screen mesh, wherein the material between the double-layer screen mesh is the product regenerated argil after screening; the aperture of the upper layer screen of the double-layer screen is 50-100 meshes, and the aperture of the lower layer screen is 350-400 meshes.

2. The regeneration method of the white oil-containing waste alkaline clay according to claim 1, wherein the frequency of the ultrasonic agitation in the step 1 is 20 to 40 kHz.

3. The regeneration method of the white oil-containing waste alkaline clay according to claim 1, wherein the ultrasonic agitation in the step 1 is realized by an ultrasonic vibrator with a frequency of 20 to 40 kHz.

4. The regeneration method of white oil-containing waste alkaline clay according to claim 1, characterized in that the solid-liquid separation of step 1 uses a clay filter.

5. The regeneration method of the white oil-containing waste alkaline clay, according to claim 1, is characterized in that the step 1 is repeated at least 1 time, when the step is repeated, the eluted clay obtained in the previous step 1 is mixed and stirred with an organic solvent, the mass ratio of the organic solvent to the white oil-containing waste alkaline clay is 3-7: 1, ultrasonic stirring is adopted in the mixing and stirring process, the stirring time is 5-15 minutes, then solid-liquid separation is carried out, the eluted clay is obtained in the solid part, and the oil-containing solvent is obtained in the liquid part; the organic solvent is dichloromethane.

6. The regeneration method of the white oil-containing waste alkaline clay according to claim 1, wherein the drying process of the step 2 is completed in a stainless steel double-cone dryer.

7. The method for regenerating spent alkaline clay containing white oil as claimed in claim 1, further comprising the step of treating the oily solvent, rectifying the oily solvent to obtain spent white oil and recovering the organic solvent.

8. The method for regenerating spent alkaline clay containing white oil according to claim 1, wherein in the step 3, the double-layer screen is a vibrating screen.

9. A regeneration method of white oil-containing waste alkaline clay is characterized by comprising the following steps:

step 1, elution: ultrasonically stirring the white oil-containing waste alkaline clay and dichloromethane, wherein the mass ratio of the dichloromethane to the white oil-containing waste alkaline clay is 5:1, the ultrasonic stirring is completed by an ultrasonic vibration rod with the frequency of 28kHz, the stirring time is 10 minutes, then, carrying out solid-liquid separation, obtaining clay after primary elution from a solid part, and obtaining an oil-containing solvent from a liquid part;

step 2, ultrasonically stirring the clay subjected to the primary elution and dichloromethane in a mass ratio of 5:1, completing ultrasonic stirring by using an ultrasonic vibration rod with the frequency of 28kHz, performing solid-liquid separation, obtaining the clay subjected to the secondary elution from a solid part, and obtaining an oil-containing solvent from a liquid part, wherein the stirring time is 10 minutes;

and 3, drying: drying the clay subjected to secondary elution by using a stainless steel double-cone dryer to obtain dried clay, wherein the drying temperature is 110 ℃, and the drying time is 30 minutes;

and 4, screening: screening the dried argil by a double-layer vibrating screen, wherein the material between double-layer screens is the product regenerated argil after screening; the aperture of the upper layer screen mesh of the double-layer screen mesh is 50 meshes, and the aperture of the lower layer screen mesh is 350 meshes;

step 5, the oil-containing solvent treatment process is also included, the oil-containing solvent treatment process is to rectify the oil-containing solvent to obtain waste white oil and recycle dichloromethane, and the rectification process is as follows: feeding an oil-containing solvent into a rectifying tower kettle, wherein the temperature of the tower kettle is 80-90 ℃, the height of the tower is 11 m, the temperature of the top of the tower is lower than 45 ℃, the reflux ratio is 1.1, after the rectification is finished, stopping feeding and reflux, heating the tower kettle to 120-130 ℃, and extracting waste white oil from the tower kettle after one hour.

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