CN110389061A - A kind of dispersing method preparing stable coal and method for estimating stability - Google Patents

A kind of dispersing method preparing stable coal and method for estimating stability Download PDF

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Publication number
CN110389061A
CN110389061A CN201910611218.3A CN201910611218A CN110389061A CN 110389061 A CN110389061 A CN 110389061A CN 201910611218 A CN201910611218 A CN 201910611218A CN 110389061 A CN110389061 A CN 110389061A
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China
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coal
stability
content
dispersing method
stablizing
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邓文安
李传
王兴兆
罗辉
杜峰
李庶峰
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China University of Petroleum East China
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China University of Petroleum East China
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G01N1/38—Diluting, dispersing or mixing samples
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00—Sampling; Preparing specimens for investigation
    • G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G01N1/44—Sample treatment involving radiation, e.g. heat
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N5/00—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid
    • G01N5/04—Analysing materials by weighing, e.g. weighing small particles separated from a gas or liquid by removing a component, e.g. by evaporation, and weighing the remainder

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)

Abstract

The invention discloses a kind of dispersing method for preparing stable coal and method for estimating stability, which includes the following steps: to carry out broken and screening process to feed coal using micronizer, and fine powdered coal is dried using rotary kiln；And the pre-heat treatment is carried out to feedstock oil using preheating furnace；The pre- hot oil of the moisture-free coal and suitable viscosity of adequate moisture and content of ashes is delivered in stirred tank respectively with certain mass flow-rate ratio, be uniformly mixed two kinds of raw materials with certain stirring rate and continues dispersion a period of time.It is provided by the invention to prepare the dispersing method and method for estimating stability for stablizing coal, the preferable coal of stability can be prepared, and estimation of stability is carried out to the coal prepared.

Description

A kind of dispersing method preparing stable coal and method for estimating stability
Technical field
The present invention relates to coal technical field, in particular to a kind of dispersing method and stability for preparing stable coal Evaluation method.
Background technique
Coal is binary heterogeneous system, and natural subsidence can occur due to gravity for coal dust, leads to coal solid-liquid point The stability of phase, system reduces.It is total in sweetening process in coal/oil plus hydrogen, deposition of the coal dust at pipeline and coal slurry pump check valve, meeting It brings pipeline blockage, equipment damage even bed layer pressure the serious consequences such as to rise sharply, the continuous run in long period of device is caused to exist Security risk greatly constrains the popularization and development of technique.In addition, state more complicated in view of the mechanism of action between coal and oil The method of the temporary not standard of the inside and outside evaluation for coal stability.
Wang Jian et al. is in " test of drilling fluid sedimentation stability is in progress with Study on Forecasting Method " by the test side of stability Method is divided into 1. static sedimentation method of testing, and 2. 3. 4. tilt angle dynamic is heavy for flow circuits sedimentation method of testing for viscosmeter sedimentation method of testing Method of testing drops.A kind of Chinese invention patent " test side of the sedimentation stability of drilling fluid of Publication No. CN103048218A Method " discloses a kind of evaluation method of drilling fluid stability, mainly comprises the steps that (a) configuration drilling fluid is spare；(b) will Drilling fluid stirs evenly, and pours into experiment container to full scale, stands certain time；(c) drilling fluid at 2/5 is taken, is measured by tool Top side liquid density, takes drilling fluid at 4/5, lower layer's drilling fluid density is measured by tool, according to measurement result, such as drilling fluid Difference of densities value of the system in graduated cylinder is zero and occurs without bleed phenomenon, then shows that sedimentation stability is good.But the method Be the density based on barite in drilling fluid be much larger than drilling well gel density, and in coal coal dust and heavy oil density and face Color is close, therefore the sedimentation situation of accurate judgement coal dust is unable to using the method that density contrast is measured by sampling and observes.
Summary of the invention
The present invention provides a kind of dispersing method for preparing stable coal and method for estimating stability, can prepare stability Preferable coal, and estimation of stability is carried out to the coal prepared.
In order to solve the above-mentioned technical problem:
In a first aspect, the embodiment of the present invention proposes a kind of dispersing method for preparing stable coal, include the following steps:
Broken and screening process is carried out to feed coal using micronizer, fine powdered coal is done using rotary kiln Dry processing；
And the pre-heat treatment is carried out to feedstock oil using preheating furnace；
The pre- hot oil of the moisture-free coal and suitable viscosity of adequate moisture and content of ashes is defeated with certain mass flow-rate ratio difference It send to stirred tank, be uniformly mixed two kinds of raw materials with certain stirring rate and continue dispersion a period of time.
Preferably, the moisture-free coal adequate moisture content is 2%~5%, and suitable content of ashes is 5%~10%；It is described Pre- hot oil is suitable for that viscosity is 500~1000mpas (120 DEG C).
Preferably, the mass flow ratio is 1:3~21:29.
Preferably, the treating capacity of the stirred tank is 1~3t/h, and stirring rate is 30~100rpm, whipping temp 120 ~160 DEG C, being dispersed with stirring the time is 1~3h.
Preferably, the treating capacity of the micronizer is 0.5~5t/h.
Preferably, the treating capacity of the rotary kiln is 0.5t/h.
Preferably, the treating capacity of the preheating furnace is 1~5t/h, and heating temperature is 80~160 DEG C.
Second aspect, the stability that the embodiment of the present invention proposes a kind of coal according to the preparation of above-mentioned dispersing method are commented Valence method, includes the following steps:
For finely dispersed coal, axial each layer solid content point is calculated using the method that solvent after Stratified Sampling is centrifuged Cloth and upper phase are to departure degree, to evaluate the stability of the coal.
Preferably, it further comprises the steps of: and finely dispersed coal is input to five side valve equivalent discharges from top to bottom, point Zhuan Yi not be in the sample to centrifuge tube of certain mass, multiple solvent, which is centrifuged and dries bottom insoluble matter, obtains actual coal in sample Powder calculates axial each layer solid content distribution and upper phase to departure degree, to evaluate the stability of coal.
Preferably, by quality of pc after centrifugation and before being centrifuged, coal mass ratio is denoted as each layer fluid solid content of coalThe ratio between the difference of upper layer fluid solid content and initial coal dust content and initial coal dust content are denoted as upper phase to departure degree θ,It is respectively as follows: with the calculation formula of θ
M in formula (1)0For the centrifuge tube bare weight before transfer sample, m1For the centrifuge tube and sample gross weight after transfer sample, m2 For the centrifuge tube and coal dust gross weight after drying；
In formula (2)Initial coal dust content when being with slurry,For upper layer fluid solid content.
By adopting the above technical scheme, by reducing feed coal partial size, screening feedstock oil viscosity, control feed coal and feedstock oil Mass flow ratio and the means that are dispersed with stirring, the preparation method of high stability coal is obtained, instead of traditional addition table The mode of face activating agent, with advantage at low cost, that pollution is small, and the raising degree of stability is significant, is more suitable for industrial life The stability of coal is controlled in production.
On the other hand, the method for estimating stability is process object with coal, by the density difference of drilling fluid and water coal The centrifugal process of slurry combines, the simple and quick each layer of axial direction that coal is calculated of method being centrifuged using solvent after Stratified Sampling Solid content distribution and upper phase are to departure degree, and the method is more suitable for the stability of evaluation coal system, and process is grasped Make simply, to repeat experimental error < 1%, have the characteristics that reproducible, accuracy is high.Also, it eliminates to measure coal Viscosity characterizes error existing for its stability, therefore has a great popularization and application foreground.
Detailed description of the invention
Fig. 1 is the dispersing method and method for estimating stability process provided in an embodiment of the present invention for preparing and stablizing coal Figure.
Specific embodiment
Specific embodiments of the present invention will be further explained with reference to the accompanying drawing.It should be noted that for The explanation of these embodiments is used to help understand the present invention, but and does not constitute a limitation of the invention.In addition, disclosed below The each embodiment of the present invention involved in technical characteristic can be combined with each other as long as they do not conflict with each other.
The processing method of feed coal use herein:
Broken and screening process is carried out to feed coal using micronizer, obtain average grain diameter be 100 mesh, 200 mesh and 500 three kinds of purpose coal dusts recycle rotary kiln that 500 mesh coal dusts are dried, and utilize industrial analysis instrument, elemental analysis Instrument carries out moisture and content of ashes, constituent content mensure to dry fine powdered coal.
Wherein, micronizer treating capacity is 0.5~5t/h.Revolution cellar treating capacity is 0.5t/h.
Raw material oil treatment process use herein:
The pre-heat treatment is carried out to feedstock oil using the preheating furnace that treating capacity is 1~5t/h, heating temperature is 80~160 DEG C, And viscosity, constituent content, race's composition distribution survey are carried out to pre- hot oil using rotational viscometer, elemental analyser, Pona analyzer It is fixed.
Coal dispersing method used in the present invention:
It is 500~1000 by moisture content is 2%~5%, content of ashes is 5%~10% moisture-free coal and viscosity The pre- hot oil of mpas (120 DEG C) is delivered to the stirring that treating capacity is 1~3t/h with the mass flow ratio of 1:3~21:29 respectively In kettle, two kinds of raw materials are uniformly mixed with the stirring rate of 30~100rpm and continue 1~3h of dispersion a period of time, whipping temp It is 120~160 DEG C.
Coal method for estimating stability used in the present invention:
Coal before and after process is stirred into 1h at 120 DEG C, by homemade estimation of stability device from upper Lower five side valves equivalent discharge sequentially obtains upper liquid, (every layer about for liquid, middle layer liquid, middle subnatant and subnatant at the middle and upper levels 235ml), and respectively in the sample to centrifuge tube for shifting certain mass (5~6g), the centrifuge tube bare weight before transfer is denoted as m0, Centrifuge tube and sample gross weight after transfer are denoted as m1.With certain proportion (sample: solvent quality ratio is 1:5~1:6) addition tetrahydro Furans is simultaneously centrifuged a 10min again with 4000rpm after stirring evenly, and is repeated several times until solution achromaticity and clarification in centrifuge tube.Dry bottom Insoluble matter obtains actual coal dust in sample, and the centrifuge tube after drying is denoted as m with coal dust gross weight2, calculated by subtracting poor method Obtain axial each layer solid content distributionWith upper phase to departure degree θ, whereinInitial coal dust content when being with slurry, For upper layer fluid solid content.
As shown in Figure 1, a kind of dispersing method for preparing stable coal and method for estimating stability, comprising the following steps:
(1) broken and screening process is carried out to feed coal using micronizer, using rotary kiln to fine powdered coal into Row is dried, and carries out moisture and content of ashes, member to dry fine powdered coal using industrial analysis instrument, elemental analyser Cellulose content measurement；
(2) the pre-heat treatment is carried out to feedstock oil using preheating furnace, and utilizes rotational viscometer, elemental analyser, Pona points Analyzer carries out viscosity, constituent content, race's composition measure of spread to pre- hot oil；
(3) by moisture content is 2%~5%, content of ashes is 5%~10% moisture-free coal and viscosity be 500~ It is 1~3t/h's that the pre- hot oil of 1000mpas (120 DEG C) is delivered to treating capacity with the mass flow ratio of 1:3~21:29 respectively In stirred tank, two kinds of raw materials are uniformly mixed with the stirring rate of 30~100rpm and continue 1~3h of dispersion a period of time；
(4) finely dispersed coal is delivered to estimation of stability unit, using homemade estimation of stability device point After layer sampling, the method for tetrahydrofuran solvent centrifugation calculates axial each layer solid content distribution and upper phase to departure degree, with Evaluate the stability of coal.
Embodiment 1
According to above-mentioned technique, in conjunction with specific feed coal and feedstock oil, the preparation for stablizing coal and stability are carried out Evaluation, actual conditions are as follows: feed coal is Xinjiang lignite (XJ), and moisture-free coal moisture content 2.03%, content of ashes 5.49% are former Material oil is catalytic cracked oil pulp (FCCS)/Ma Ruichang slag (MRAR)/Ma Ruichang slag (MRAR) and catalytic cracked oil pulp (FCCS) matter The miscella (M:F=1:1) that amount ratio is 1:1, viscosity 173/1806/312mpas, coal: oily mass flow ratio 1:3/21: 29,150 μm of coal particle size, stirring rate 30rpm, jitter time 1h, 120 DEG C of whipping temp, test specific data such as the following table 1:
Table 1
Above-mentioned raw materials and condition are repeated, the specific data of partial test such as the following table 2:
Table 2
Embodiment 2
According to above-mentioned technique, in conjunction with specific feed coal and feedstock oil, the preparation for stablizing coal and stability are carried out Evaluation, actual conditions are as follows: feed coal is Xinjiang lignite (XJ), and moisture-free coal moisture content 2.03%, content of ashes 5.49% are former The miscella (M:F=1:1) that material oil is Ma Ruichang slag (MRAR) and catalytic cracked oil pulp (FCCS) mass ratio is 1:1, viscosity 312mpas, coal: oily mass flow ratio 21:29,150 μm of coal particle size, stirring rate 30/100rpm, jitter time 1/ 3h, tests specific data such as the following table 3 by 120/160 DEG C of whipping temp:
Table 3
By embodiment 1 and embodiment 2 it is found that dispersing method of the present invention can make the upper phase of coal to inclined It is lower than 10% from degree, effectively increases the stability of coal system, and the repetition experimental error < 1% of determination of solid content, Have the advantages that applied widely, reproducible, accuracy is high.
In conjunction with attached drawing, the embodiments of the present invention are described in detail above, but the present invention is not limited to described implementations Mode.For a person skilled in the art, in the case where not departing from the principle of the invention and spirit, to these embodiments A variety of change, modification, replacement and modification are carried out, are still fallen in protection scope of the present invention.

Claims (10)

1. a kind of dispersing method for preparing stable coal, which comprises the steps of:
Broken and screening process is carried out to feed coal using micronizer, place is dried to fine powdered coal using rotary kiln Reason；
And the pre-heat treatment is carried out to feedstock oil using preheating furnace；
The pre- hot oil of the moisture-free coal and suitable viscosity of adequate moisture and content of ashes is delivered to respectively with certain mass flow-rate ratio In stirred tank, two kinds of raw materials are uniformly mixed with certain stirring rate and continue dispersion a period of time.
2. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the moisture-free coal is suitable for water Dividing content is 2%~5%, and suitable content of ashes is 5%~10%；The pre- hot oil is suitable for that viscosity is 500~1000mpas (120℃)。
3. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the mass flow ratio is 1:3~21:29.
4. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the processing of the stirred tank Amount is 1~3t/h, and stirring rate is 30~100rpm, and whipping temp is 120~160 DEG C, and being dispersed with stirring the time is 1~3h.
5. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the micronizer Treating capacity is 0.5~5t/h.
6. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the processing of the rotary kiln Amount is 0.5t/h.
7. according to claim 1 prepare the dispersing method for stablizing coal, which is characterized in that the processing of the preheating furnace Amount is 1~5t/h, and heating temperature is 80~160 DEG C.
8. a kind of method for estimating stability of the coal of -7 any dispersing method preparations according to claim 1, feature It is, includes the following steps:
For finely dispersed coal, using the method that solvent after Stratified Sampling is centrifuged calculate axial each layer solid content distribution and Upper phase is to departure degree, to evaluate the stability of the coal.
9. method for estimating stability according to claim 8, which is characterized in that further comprise the steps of: finely dispersed oil Coal slurry is input to five side valve equivalent discharges from top to bottom, in the sample to centrifuge tube for shifting certain mass respectively, multiple solvent It is centrifuged and dries bottom insoluble matter and obtain actual coal dust in sample, calculate axial each layer solid content distribution and upper phase to inclined From degree, to evaluate the stability of coal.
10. method for estimating stability according to claim 8, which is characterized in that before quality of pc after centrifugation and centrifugation Coal mass ratio is denoted as each layer fluid solid content of coalBy the difference of upper layer fluid solid content and initial coal dust content and just The ratio between beginning coal dust content is denoted as upper phase to departure degree θ,It is respectively as follows: with the calculation formula of θ
M in formula (1)0For the centrifuge tube bare weight before transfer sample, m1For the centrifuge tube and sample gross weight after transfer sample, m2It is dry Centrifuge tube and coal dust gross weight after dry；
In formula (2)Initial coal dust content when being with slurry,For upper layer fluid solid content.
CN201910611218.3A 2019-07-08 2019-07-08 A kind of dispersing method preparing stable coal and method for estimating stability Pending CN110389061A (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101333448A (en) * 2008-07-09 2008-12-31 煤炭科学研究总院 Direct liquefaction process of coal by replacing circling solvent with petroleum or petroleum refining byproduct
CN102115674A (en) * 2009-12-30 2011-07-06 中国石油化工股份有限公司 Coal liquefaction and petroleum refining combined method
CN108504378A (en) * 2017-02-28 2018-09-07 中科合成油技术有限公司 A kind of preparation method of coal hydrogenation pyrolysis hydrogen supply dissolvent oil, the hydrogen supply dissolvent oil and application thereof thus prepared
CN108872526A (en) * 2018-06-25 2018-11-23 陕西延长石油（集团）有限责任公司 A kind of rapid detection method of coal stability

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101333448A (en) * 2008-07-09 2008-12-31 煤炭科学研究总院 Direct liquefaction process of coal by replacing circling solvent with petroleum or petroleum refining byproduct
CN102115674A (en) * 2009-12-30 2011-07-06 中国石油化工股份有限公司 Coal liquefaction and petroleum refining combined method
CN108504378A (en) * 2017-02-28 2018-09-07 中科合成油技术有限公司 A kind of preparation method of coal hydrogenation pyrolysis hydrogen supply dissolvent oil, the hydrogen supply dissolvent oil and application thereof thus prepared
CN108872526A (en) * 2018-06-25 2018-11-23 陕西延长石油（集团）有限责任公司 A kind of rapid detection method of coal stability

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Title
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