CN102649632B - Coal pitch mixture and preparation method thereof - Google Patents
Coal pitch mixture and preparation method thereof Download PDFInfo
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- CN102649632B CN102649632B CN 201210110612 CN201210110612A CN102649632B CN 102649632 B CN102649632 B CN 102649632B CN 201210110612 CN201210110612 CN 201210110612 CN 201210110612 A CN201210110612 A CN 201210110612A CN 102649632 B CN102649632 B CN 102649632B
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Abstract
The invention discloses a coal pitch mixture, which comprises road coal pitch and mineral aggregate, wherein the weight ratio of the road coal pitch to the mineral aggregate is 6-3:94-97; the road coal pitch consists of the following components in percentage by mass: 10-80 percent of coal pitch, 15-76 percent of petroleum pitch, 3-8 percent of alkyl acid or alkyl acid salt and 2-6 percent of low molecular weight polyethylene. The invention also discloses a preparation method of the coal pitch mixture. The temperature of the coal pitch mixture is reduced by 20-30 DEG C during mixing and construction compared with hot mixed pitch mixture; the emission of pitch gas can be obviously reduced and the effect of suppressing the toxicity of the coal pitch is achieved; and thermo-oxidative aging of the pitch is reduced and the aims of energy conservation and emission reduction are fulfilled. The obtained coal pitch mixture is easier to compact; and indexes such as compactness, water stability, high temperature performance and low temperature performance of a paved pavement are not less than those of the hot mixed pitch mixture of the same grade.
Description
Technical field
The invention belongs to the road engineering technical field, but especially relate to a kind of low-temperature construction that is applicable to road project, energy-conservation coal-tar pitch compound.
The invention still further relates to the preparation method of above-mentioned coal-tar pitch compound.
Background technology
Along with increasing the weight of day by day of China's volume of traffic and load, more and more higher to the requirement of category of roads and bituminous pavement functional quality.Meanwhile along with the continuous of International Crude Oil risen, oil and related products imbalance between supply and demand become increasingly conspicuous, and China is coal resources big countries, and utilizing coal resources to replace relevant petroleum products will be Future in China development main trend.The output of the present coal-tar pitch of China has reached 2,000,000 tons, accounts for more than 50% of coal tar total amount.And the coal-tar pitch resource price is cheap, does not also have high value added utilization preferably.
At present, most bituminous pavements realize that by hot-mix asphalt mixture its mix and construction temperature are very high, and in general matrix pitch need be heated to 160 ℃, if adopt modifying asphalt, the mix temperature also will improve more than 20 ℃.From other angle, pitch is under the situation of high temperature and aerobic, and is aging inevitable; Pitch and the high temperature that gathers materials and be heated to 160-180 ℃ must consume a large amount of energy fuels.
Coal-tar pitch is a kind of complex component compound that contains polycyclic aromatic hydrocarbons, wherein contained polycyclic aromatic hydrocarbons toxic substances such as (as anthracene, phenanthrene, pyrene, benzopyrenes) discharges in the hot-mix asphalt mixture construction process, be easy to cause environmental pollution and personnel health's influence, particularly 3,4 contained benzopyrenes are again the one of the main reasons that causes skin carcinoma, lung cancer and esophagus cancer in pitch wherein and the glance coal.
Because the mix temperature height of hot-mix asphalt mixture, at mix and when paving and be not suitable for containing the processing of coal-tar pitch.And the performance of asphalt has material impact for permanent seal cooling and the long-term behaviour thereof of road engineering.In sum, how can utilize cheap coal-tar pitch resource, can satisfy the preparation complete processing of asphalt again, and guarantee the life-time service performance of road, be the direction that present scientific research institution concentrates research.
Summary of the invention
But the object of the present invention is to provide a kind of low-temperature construction, energy-conservation coal-tar pitch compound.
Another purpose of the present invention is to provide a kind of method for preparing above-mentioned coal-tar pitch compound.
For achieving the above object, coal-tar pitch compound provided by the invention comprises road coal-tar pitch and mineral aggregate, and the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: 94-97; Wherein, the composition of road coal-tar pitch by mass ratio is:
Coal-tar pitch 10-80%;
Petroleum pitch 15-76%;
Alkyl acid or alkyl hydrochlorate 3-8%;
Low molecular weight polyethylene 2-6%.
Described coal-tar pitch compound, wherein, the petroleum pitch in the described road coal-tar pitch is for satisfying the road oil A level pitch that " asphalt highway construction technique normalizing " (JTG F40-2004) requires.
Described coal-tar pitch compound, wherein, the coal-tar pitch in the described road coal-tar pitch is the coal-tar pitch that coal tar that the dry distillation of coal obtains is processed into through distillation again, softening temperature 75-120 ℃, toluene insolubles content is less than 15%.
Described coal-tar pitch compound, wherein, the coal-tar pitch in the described road coal-tar pitch is the coal-tar pitch powder of grinding and sieving, is the 60-200 order.
Described coal-tar pitch compound, wherein, the alkyl acid in the described road coal-tar pitch or the structural formula of alkyl hydrochlorate are CxHyOzMn, x=12-20, y=30-80, z=2-10, n=1-2, M are sodium, magnesium, calcium, zinc or barium.
Described coal-tar pitch compound, wherein, the low molecular weight polyethylene in the described road coal-tar pitch refers to that molecular weight is the polyethylene of 1000-4000.
The method of the above-mentioned coal-tar pitch compound of preparation provided by the invention, key step is:
1) earlier that mass ratio is softening mobile for the 10-80% coal-tar pitch is heated to, add the petroleum pitch that mass ratio is 15-76% again, under 100-120 ℃, adding mass ratio is alkyl acid or the alkyl hydrochlorate of 3-8%, mass ratio is the 2-6% low molecular weight polyethylene, be 2000-3000r/min with high-speed shearing machine in shearing rate, shear 20-30 minute down cut and obtain the road coal-tar pitch;
2) the road coal-tar pitch is heated to 120-130 ℃, mineral aggregate is heated to 140-145 ℃, and the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: obtain the coal-tar pitch compound after 94-97 stirs.
Described preparation method, wherein, the structural formula of alkyl acid or alkyl hydrochlorate is CxHyOzMn, x=12-20, y=30-80, z=2-10, n=1-2, M are sodium, magnesium, calcium, zinc or barium.
Described preparation method, wherein, low molecular weight polyethylene refers to that molecular weight is the polyethylene of 1000-4000.
Described preparation method, wherein, the duration of mixing of road coal-tar pitch and mineral aggregate is 20-90 second.
The present invention prepares the road coal-tar pitch by coal-tar pitch, petroleum pitch, alkyl hydrochlorate and low molecular polyethylene blend allotment, again road coal-tar pitch and mineral aggregate is mixed with the coal-forming asphalt.Compared with prior art, the high-temperature behavior that coal-tar pitch compound of the present invention has not only improved the road coal-tar pitch reaches the building stones adhesivity, and effectively reduces construction temperature, reduces the discharging of glance coal, and obtained the pitch articles of stable storing, be fit to carrying out of road low-temperature construction engineering.
Description of drawings
Fig. 1 is 70# matrix pitch viscosity-temperature curve;
Fig. 2 is embodiment 3 viscosity-temperature curves;
Fig. 3 is embodiment 7 viscosity-temperature curves.
Embodiment
Incompatible when the objective of the invention is to improve coal-tar pitch and petroleum pitch and mixing, the release that poor stability and heat are mixed process medium pitch cigarette and poisonous component thereof, a kind of low-temperature construction is provided, reduces coal-tar pitch compound and Preparation Method thereof that mixture laying process medium pitch cigarette discharges.
Technical scheme of the present invention provides a kind of road coal-tar pitch, and road coal-tar pitch of the present invention and mineral aggregate are mixed with the coal-forming asphalt.
Specifically, coal-tar pitch compound of the present invention is made up of road coal-tar pitch and mineral aggregate, and wherein the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: 94-97; The composition of road coal-tar pitch by mass ratio is: coal-tar pitch 10-80%, petroleum pitch 15-76%, alkyl acid or alkyl hydrochlorate 3-8%, and low molecular weight polyethylene 2-6%.
The preparation method of road coal-tar pitch of the present invention, its concrete implementation step is as follows:
Earlier that mass fraction is softening mobile for the 10-80% coal-tar pitch is heated to, add the petroleum pitch that mass fraction is 15-76% again, under 100-120 ℃, the alkyl acid or the alkyl hydrochlorate that add 3-8%, the 2-6% low molecular weight polyethylene, be 2000-3000r/min with high-speed shearing machine in shearing rate, shear 20-30 minute down cut and obtain the road coal-tar pitch.Following examples prepare the specific embodiment of road coal-tar pitch for the present invention.
Embodiment 1
The 70# matrix petroleum pitch of mass ratio 77% is heated to 150 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 15% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid magnesium of adding 3%, 5% low molecular weight polyethylene, with the VELOCITY SHEAR 20min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 2
The 70# matrix petroleum pitch of mass ratio 82% is heated to 130 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 10% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid zinc of adding 4%, 4% low molecular weight polyethylene, with the VELOCITY SHEAR 30min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 3
The 70# matrix petroleum pitch of mass ratio 75% is heated to 130 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 15% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid sodium of adding 6%, 4% low molecular weight polyethylene, with the VELOCITY SHEAR 25min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 4
The 70# matrix petroleum pitch of mass ratio 75% is heated to 130 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 15% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid sodium of adding 8%, 2% low molecular weight polyethylene, with the VELOCITY SHEAR 30min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 5
The 70# matrix petroleum pitch of mass ratio 75% is heated to 150 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 15% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid magnesium of adding 5%, 5% low molecular weight polyethylene, with the VELOCITY SHEAR 30min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 6
The 70# matrix petroleum pitch of mass ratio 70% is heated to 130 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 20% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid sodium of adding 2%, 3% low molecular weight polyethylene, with the VELOCITY SHEAR 30min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Embodiment 7
The 70# matrix petroleum pitch of mass ratio 70% is heated to 150 ℃, coal-tar pitch powder after the fragmentation of adding mass ratio 20% is sieved, stirring treats that coal-tar pitch is dissolved in petroleum pitch, the alkyl acid sodium of adding 4%, 6% low molecular weight polyethylene, with the VELOCITY SHEAR 20min of 4000r/min, dissolving evenly namely makes road coal-tar pitch product.
Performance test
Test method is according to the Ministry of Communications's industry standard " highway engineering pitch and asphalt testing regulation (JTG E20-2011) ", and the product 1-7 that protopetroleum pitch and above-described embodiment 1-7 are prepared carries out the test of softening temperature, 25 ℃ of penetration degrees and 135 ℃ of brookfield viscosities respectively.Test result sees Table 1.
As can be seen from Table 1, the softening temperature of modifying asphalt raises to some extent than matrix pitch, and penetration degree slightly reduces simultaneously, illustrates that the high-temperature behavior of pitch is improved.135 ℃ of brookfield viscosities have more obviously reduction than matrix pitch simultaneously, can effectively reduce the mix temperature when construction is described, are beneficial to construction.
The preparation of coal-tar pitch compound:
1) any road coal-tar pitch among the embodiment 1-7 is heated to 125 ℃, mineral aggregate is heated to 135 ℃.Need to prove that emphasis of the present invention provides the road coal-tar pitch, the mineral aggregate that adopts in preparation coal-tar pitch compound is the sandstone material that satisfies the transportation industry respective standard, and mineral aggregate gradation is also undertaken by the known technology of category of roads.
2) begin mix in the road coal-tar pitch input amalgamator with heating, add the mineral aggregate of powdery after the pitch sprinkling is finished, the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: 94-97, and final mix becomes asphalt.
According to " highway engineering pitch and asphalt testing regulation (JTG E20-2011) " the compound employing AC-20 grating of embodiment 3,7 and No. 70 matrix petroleum pitch pitches is carried out conventional Marshall performance, water stability energy, high temperature stability performance contrast test.Wherein, high-temperature stability embodies by rut dynamic stability index.
From the test result of table 2, table 3, table 4 as can be seen, the Marshall stability value of coal-tar pitch compound of the present invention increases than No. 70 petroleum pitch; The water stability of road coal-tar pitch compound can improve, and wherein embodiment 3 coal-tar pitch compound residual stabilities are compared No. 70 petroleum pitch raisings 2.8% and 14% with freeze thawing tensile splitting strength ratio; The coal-tar pitch compound dynamic stability of embodiment 3 and embodiment 7 is compared No. 70 petroleum pitch and has been improved 41.7% and 80.7% respectively; Illustrate that road coal-tar pitch high temperature stability performance significantly improves, rutting resistance significantly strengthens.
Adopt stability at high temperature of asphalt mixture, the water stability of road coal-tar pitch compound of the present invention moulding at a lower temperature significantly to be better than mixing the matrix pitch compound with heat under the condition, the mix temperature that adopts the present invention can reduce the road coal-tar pitch is described, and can not slacken the performance index of compound, have good " temperature is mixed " effect.
Viscosity-temperature curve and cost-effectiveness analysis
By temperature in viscosity-temperature curve (Fig. 1, Fig. 2, Fig. 3) and the table 5-viscosity data contrast, the mix temperature of embodiment 3 and embodiment 7 reduces about 10 ℃, but the reflection of the data of viscosity-temperature curve is recommendation mix and the compacting temperature of No. 70 matrix petroleum pitch.Mix the recommendation mix temperature of road coal-tar pitch and determine according to viscosity-temperature curve and practical experience, reduce 20-30 ℃ approximately through testing the mix temperature of determining embodiment 3 and embodiment 7.
In a word, the temperature that adopt to reduce the mix temperature is mixed the every performance index of coal-tar pitch compound and is not less than heat and mixes the petroleum pitch compound, has also obtained significantly improving aspect high-temperature stability; Owing to reduced construction temperature, difficulty of construction reduces, the easier assurance of construction quality.Studies show that, adopt this technology can obviously reduce the fuel oil consumption of heated bitumen, according to actual engineering survey (table 6), the coal-tar pitch compound mixes and stirs temperature and is reduced to 120 ℃ from 150 ℃, heating can be reduced to 5.3kg/t from 6.4kg/t with fuel oil consumption, actual consumption reduction 17%.
Table 1: the performance of each embodiment pitch
Table 2: Marshall Test volume index
Table 3: water stability test
Table 4: rut dynamic stability index test result
| Numbering | Dynamic stability (mm/ time) |
| 70# matrix pitch compound | 1041 |
| Example 3 compounds | 1476 |
| Example 7 compounds | 1881 |
Table 5: each embodiment temperature-viscosity data detected result
| Numbering | 120℃ | 135 |
150℃ |
| 70# matrix | 0.759 | 0.335 | 0.175 |
| Example 3 | 0.526 | 0.254 | 0.132 |
| Example 7 | 0.534 | 0.266 | 0.143 |
Table 6: pitch mixing station fuel oil consumption situation
| Mix type | Drop temperature | Fuel consumption | Energy-conservation |
| Heat is mixed the |
150 | 6.4 | - |
| Embodiment 3 | 120 | 5.3 | 17％ |
Claims (10)
1. a coal-tar pitch compound comprises road coal-tar pitch and mineral aggregate, and the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: 94-97; Wherein, the composition of road coal-tar pitch by mass ratio is:
Coal-tar pitch 10-80%;
Petroleum pitch 15-76%;
Alkyl acid or alkyl hydrochlorate 3-8%;
Low molecular weight polyethylene 2-6%.
2. coal-tar pitch compound according to claim 1, wherein, the petroleum pitch in the described road coal-tar pitch is for satisfying the road oil A level pitch that " asphalt highway construction technique normalizing " (JTG F40-2004) requires.
3. coal-tar pitch compound according to claim 1, wherein, the coal-tar pitch in the described road coal-tar pitch is the coal-tar pitch that coal tar that the dry distillation of coal obtains is processed into through distillation again, softening temperature 75-120 ℃, toluene insolubles content is less than 15%.
4. according to claim 1 or 3 described coal-tar pitch compounds, wherein, the coal-tar pitch in the described road coal-tar pitch is the coal-tar pitch powder of grinding and sieving, is the 60-200 order.
5. coal-tar pitch compound according to claim 1, wherein, the alkyl acid in the described road coal-tar pitch or the structural formula of alkyl hydrochlorate are CxHyOzMn, x=12-20, y=30-80, z=2-10, n=1-2, M are sodium, magnesium, calcium, zinc or barium.
6. coal-tar pitch compound according to claim 1, wherein, the low molecular weight polyethylene in the described road coal-tar pitch refers to that molecular weight is the polyethylene of 1000-4000.
7. the method for preparing the described coal-tar pitch compound of claim 1, key step is:
1) earlier that mass ratio is softening mobile for the 10-80% coal-tar pitch is heated to, add the petroleum pitch that mass ratio is 15-76% again, under 100-120 ℃, adding mass ratio is alkyl acid or the alkyl hydrochlorate of 3-8%, mass ratio is the 2-6% low molecular weight polyethylene, be 2000-3000r/min with high-speed shearing machine in shearing rate, shear 20-30 minute down cut and obtain the road coal-tar pitch;
2) the road coal-tar pitch is heated to 120-130 ℃, mineral aggregate is heated to 140-145 ℃, and the weight ratio of road coal-tar pitch and mineral aggregate is 6-3: obtain the coal-tar pitch compound after 94-97 stirs.
8. method according to claim 7, wherein, the structural formula of alkyl acid or alkyl hydrochlorate is CxHyOzMn, x=12-20, y=30-80, z=2-10, n=1-2, M are sodium, magnesium, calcium, zinc or barium.
9. method according to claim 7, wherein, low molecular weight polyethylene refers to that molecular weight is the polyethylene of 1000-4000.
10. method according to claim 7, wherein, the duration of mixing of road coal-tar pitch and mineral aggregate is 20-90 second.
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| CN103450693B (en) * | 2013-09-18 | 2016-05-25 | 交通运输部公路科学研究所 | Composite modified coal tar pitch and preparation method thereof |
| CN103694715A (en) * | 2013-12-03 | 2014-04-02 | 苏州惠丰润滑油有限公司 | Novel vacuum sealing material composition |
| CN103694716B (en) * | 2013-12-10 | 2016-03-09 | 柳州博泽科技有限公司 | Coal asphalt product of modification and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101765641A (en) * | 2007-07-26 | 2010-06-30 | 阿克佐诺贝尔股份有限公司 | adhesion and cohesion modifiers for asphalt |
| CN102225854A (en) * | 2011-05-03 | 2011-10-26 | 深圳市科中大交通建材有限公司 | Bituminous mixture modifier as well as preparation method and application thereof |
| CN102408729A (en) * | 2011-08-17 | 2012-04-11 | 交通运输部公路科学研究所 | Polyethylene composite modified asphalt with stable storage and preparation method thereof |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101765641A (en) * | 2007-07-26 | 2010-06-30 | 阿克佐诺贝尔股份有限公司 | adhesion and cohesion modifiers for asphalt |
| CN102225854A (en) * | 2011-05-03 | 2011-10-26 | 深圳市科中大交通建材有限公司 | Bituminous mixture modifier as well as preparation method and application thereof |
| CN102408729A (en) * | 2011-08-17 | 2012-04-11 | 交通运输部公路科学研究所 | Polyethylene composite modified asphalt with stable storage and preparation method thereof |
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