WO2013029410A1

WO2013029410A1 - Processing technique of pulverized lignite

Info

Publication number: WO2013029410A1
Application number: PCT/CN2012/077187
Authority: WO
Inventors: 李柏荣
Original assignee: Li Bairong
Priority date: 2011-09-02
Filing date: 2012-06-20
Publication date: 2013-03-07
Also published as: CN102337167A; CN102337167B

Abstract

A processing technique of pulverized lignite comprises the following steps: 1) heating pulverized lignite to 100°C-1000°C, and keeping the temperature for 1h~5h; 2) cooling the lignite obtained in Step 1) to be below 100°C; 3) adding a binder, mixing evenly, and forming; 4) heating the formed lignite to 100°C~1000°C, and keeping the temperature for 1h~5h.For the final product obtained through the processing technique of pulverized lignite according to the present invention, the low calorific value is greatly increased when compared with that of raw coal, and is increased to be more than 2 times as that of the raw coal not modified. Dehydration is almost completely performed, the volatile matter is dramatically reduced, the content of fixed carbon is increased dramatically, and the yield of condensed water is high. Compared with the prior art, the processing technique of the present invention has lower cost, and obtains the product not only easy to transport but also having the high calorific value.

Description

The present invention claims the priority of the Chinese patent application filed on September 2, 2011, the Chinese Patent Office, Application No. 201110259859.0, entitled "Processing Process of Powdered Brown Coal", The entire contents are incorporated herein by reference. Technical field

The invention relates to the technical field of treatment of powdered lignite, in particular to a treatment process of powder brown coal with low cost and good treatment effect.

Background technique

Lignite, also known as diesel coal, is the coal with the lowest degree of coalification, accounting for about 40% of global coal reserves.

China's coal reserves are 13%, and the reserves are extremely large. However, due to the high moisture content of brown coal (about 20%~40%), low calorific value, easy weathering and spontaneous combustion, the transportation cost per unit of energy is high, which is not conducive to long-distance transportation and storage. This restricts the application and development of lignite. In some countries and regions, such as Victoria in Australia, most of the lignite is powdery in microstructure, high in water content, and has a high autoignition index. If it is not treated, it is difficult to export to other countries or regions through long-distance transportation. The powdered lignite referred to herein means that, in general, lignite itself is powdery and has a particle size of about 5 mm or less, but extremely fine powdery lignite is agglomerated and formed loose due to high surface area due to high specific surface area. In the case of the combined large agglomerates, the above-mentioned loosely combined large agglomerates, fine powders produced during the processing of raw coal, and fine powders formed by crushing and grinding of bulk lignite are all in the category of powdered lignite. The general means to solve the problem of difficult transportation of powdered lignite is to gasify or liquefy lignite, but these methods are costly. Another method is to treat these powdered lignites with or without treatment, and then add additives such as binders, combustion improvers, catalysts, etc., and then form them into briquettes for convenient transportation and further utilization.

In addition, the thermal efficiency of lignite direct combustion is low, and the greenhouse gas emissions are also large, making it difficult to develop and utilize on a large scale. Furthermore, the conversion and utilization of lignite as a raw material is also limited. Lignite liquefaction, dry distillation and gasification all require that the moisture in the coal be reduced to less than 10%. If lignite is not upgraded, it will be difficult to meet the quality requirements of many users. It can be seen that the lignite upgrading process becomes a lignite efficient opening. The key to utilization. The term "lignite upgrading" as used herein refers to the change in the composition and structure of coal in the process of dehydration, molding and thermal decomposition of lignite, which is converted into upgraded coal with similar properties of bituminous coal. Blast furnace injection is a new technology widely used in modern blast furnace ironmaking production. It plays an important role in improving economic efficiency and reducing the cost of pig iron. It has been highly valued by countries all over the world and has made remarkable progress in recent decades. Among them, the injection of pulverized coal technology is being continuously promoted and applied in the related new ironmaking process. The main reason is: the use of coal instead of coke, reducing the demand for coke iron in the blast furnace. The main role of blast furnace coal injection in the pig iron smelting process is to partially replace metallurgical coke and reduce coke consumption. Therefore, if a large amount of lignite is produced into blast furnace coal, the ironmaking cost will be greatly saved. Summary of the invention

In view of the above, an object of the present invention is to provide a treatment process for powdered lignite which can achieve a better treatment effect at a lower cost.

In order to solve the above technical problem, the technical solution of the present invention is:

A processing method of powdered lignite includes the following steps:

1) heating the powdered lignite to 100 ° C ~ 1000 ° C, and then heat lh ~ 5h;

2) cooling the lignite obtained in the step 1) to below 100 ° C;

3) Adding a binder and stirring it to form a post;

4) Heat the lignite after molding to 100 ° C ~ 1000 ° C, heat lh ~ 5h.

Preferably, in step 1), the powdered lignite is heated to 250 ° C ~ 350 ° C, and then insulated

2h~2.5h.

Preferably, in step 1), the powdered lignite is heated to 300 ° C and then incubated for 2 h.

Preferably, in step 4), the mixture is heated to 300 ° C to 800 ° C, and then incubated for 2 h to 4 h.

Preferably, in step 4), it is heated to 650 ° C and then incubated for 2 h.

Preferably, in step 2), natural cooling or forced cooling is employed.

Preferably, the powdery lignite has a particle diameter of 5 mm or less.

Preferably, the powdery lignite has a particle diameter of 2 mm or less.

Preferably, in step 3), the ratio of the binder to the lignite is 50 to 99 parts by weight of brown coal and 1 to 50 parts of binder. Preferably, in step 3), the ratio of the binder to the lignite is: 60 to 90 parts of lignite and 10 to 40 parts of binder.

Preferably, in step 3), the ratio of the binder to the lignite is: 70-85 parts of lignite and 15-30 parts of binder.

Preferably, in step 3), the ratio of the binder to the lignite is: lignite by weight:

80 parts, 20 parts of binder.

Preferably, the binder is an organic binder or an inorganic binder or an organic composite binder, an inorganic composite binder, and an organic-inorganic composite binder.

Preferably, the binder is a tar pitch type binder.

Preferably, the binder is any one or a mixture of two or more of coal tar pitch, petroleum pitch, petroleum residue, coal tar, and tar residue.

Preferably, the binder is a polymeric binder.

Preferably, the binder is any one of polyethylene, polyvinyl alcohol, polystyrene, phenol resin, synthetic resin, polyurethane, and resin latex.

Preferably, the binder is any one of starch or pulp waste liquid and biomass, and the biomass is crop waste.

Preferably, the crop waste is any one of wheat straw, straw, glutinous rice core, glutinous rice rod, wood chips, bark, and trunk.

Preferably, the binder is an inorganic binder.

Preferably, the binder is lime or cement or gypsum.

Preferably, the binder is a clay binder.

Preferably, the binder is sodium silicate.

Preferably, the binder is made up of 15 to 30 parts of a PVFM solution, 1 to 4 parts of sodium humate, and 66 to 85 parts of water, wherein the PVFM solution comprises: polyvinyl alcohol 2 to 6 Parts, 1.5~3 parts of formaldehyde and 90~95 parts of water.

Preferably, the binder is made up of 20 parts of PVFM solution, 2 parts of sodium humate, and 78 parts of water, wherein the PVFM solution comprises: 4.85 parts of polyvinyl alcohol, 2.43 parts of formic acid, and 92.72 of water. Share.

Preferably, in step 1) and step 3), the heating of the powdered lignite is in the following device In any one of the following: tunnel kiln, fluidized bed furnace, suspension roaster, rotary kiln, drying device, fin modification device.

Preferably, the drying device is a twin-screw upgrading and deliming device, comprising two hollow shafts, wherein the hollow shaft is distributed with a plurality of hollow blades, and the heat-conducting oil enters the hollow shaft and the hollow blade cavity. The wall surface of the hollow blade is used as a heat transfer medium to modify the powdered lignite.

Preferably, the fin reforming device performs heating, and the fin reforming device comprises a casing, a feeding end and a discharging end respectively disposed at two ends of the casing, and at least two stages of exhausting are provided from the center of the casing from the inside to the outside. a passage, the exhaust passage is electrically connected to an exhaust end disposed on the outer casing; a heat conducting mechanism is disposed in the cavity between the feeding end and the discharging end of the outer casing, and the heat conducting mechanism is close to the discharging A heat conducting medium inlet is disposed at the end, and a heat conducting medium outlet is disposed near the feeding end, the heat conducting mechanism includes a plurality of sets of spaced apart heat conducting units, the heat conducting unit includes a plurality of heat conducting tubes, the heat conducting tube and the heat conducting medium The inlet and the heat-conducting medium outlet are turned on, and a plurality of fins inclined downward from the vertical direction are arranged between the adjacent heat-conducting tubes, fins are disposed between the heat-conducting tubes beside the exhaust passage, and the lower end portion is away from the row The direction of the gas passage is inclined to block the exhaust port opened on the wall of the exhaust passage.

Compared with the prior art, the treatment process of the powdered lignite of the present invention is carried out by heating and maintaining the raw coal by adopting two modification methods: first heating the powdered lignite to 100 ° C ~ 1000 ° C, and then After heat preservation for lh~5h, the modified brown coal obtained is cooled to below 100 °C, and most of the water is removed by the drying; then the second heating is performed to remove the volatile matter, that is, the lignite obtained in one heating and heat preservation. The binder is added, and the mixture is stirred and then formed, and then the pellet is continuously heated and heat-treated, heated to 100 ° C to 1000 ° C, and kept for 1 h to 5 h, and finally the product obtained, the low calorific value ratio The raw coal is greatly improved, which is more than doubled compared with the raw coal before upgrading; the whole water is almost completely removed, the volatile content is greatly reduced, the fixed carbon content is greatly increased, and the yield of condensed water is large; compared with the prior art, The treatment process of the invention is lower in cost, and the obtained product can be easily transported and has a high calorific value.

DRAWINGS

Figure 1 is a flow chart showing the treatment process of the powdered brown coal of the invention;

2 is a schematic structural view of a twin-screw drying device used in a treatment process of powdered lignite according to the present invention; Figure 3 is an internal structural view of Figure 2;

Fig. 4 is a schematic view showing the structure of a fin reforming apparatus used in the treatment process of powdered lignite according to the present invention.

Figure 5 is an enlarged view of the portion C in Figure 4;

Figure 6 is an enlarged view of D in Figure 4.

Fig. 7 is a structural view of the feeding portion of the fin reforming device and the outlet portion of the heat conducting medium in Fig. 4 (the direction indicated by the arrow in the figure is the direction in which the heat conducting medium is led). detailed description

In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Referring to Figure 1, the treatment process of the powdered brown coal of the present invention comprises the following steps:

1) One heating and heat preservation: The powdered lignite is heated to 100 ° C ~ 1000 ° C, and then insulated for lh ~ 5h;

2) cooling: the lignite obtained in the step 1) is cooled to below 100 ° C;

3) Adding a binder to form: further adding a binder and stirring and then forming;

4), secondary heating, heat preservation: The lignite after molding is heated to 100 ° C ~ 1000 ° C, and kept for lh ~ 5h.

The details are described below by way of specific examples.

Embodiment 1

The treatment process of the powdered lignite in this embodiment comprises the following steps:

1) The powdered lignite is heated and dried in a twin-screw drying device, and the water is removed, and the heating temperature is 300 ° C, and the temperature is kept for 2 hours;

2) Then, the lignite obtained in the step 1) is naturally cooled to 100 ° C, and discharged;

3) mixing and cooling the lignite added binder, and then pressing and forming the ball;

4) The pellet was charged into the fin reforming device, heated to 650 ° C, and then incubated for 2 hours, and the obtained coal to be modified was cooled to 100 ° C to discharge.

In the step 3), the ratio of the lignite to the binder is: 50 parts of lignite and 1 part of binder.

Among them, 20 parts by weight of PVFM solution, 2 parts of sodium humate, water 78 by weight The PVFM solution comprises: 4.85 parts of polyvinyl alcohol, 2.43 parts of formic acid, and 92.72 parts of water.

The structure of the twin-screw drying device in step 1) is shown in Fig. 2 and Fig. 3, and two hollow shafts A1 are arranged, and a plurality of hollow blades A2 are arranged on the outer side wall of each hollow shaft A1, and the hollow blades are arranged. The leaf A2 is electrically connected to the cavity of the hollow shaft A1, and the heat transfer oil in the cavity of the hollow shaft A1 enters the cavity of the hollow blade A2, and the hollow shaft A1 is continuously rotated by the driving device to drive the hollow paddle. The leaf A2 is rotated, and the wall surface of the hollow blade A2 is in contact with the lignite as a heat transfer medium, and the lignite is stirred and dried.

Among them, the twin-screw drying device used in this embodiment has the following advantages:

1. The internal pressure during the drying process is generally greater than the external pressure, thus isolating the entry of foreign substances, isolating the influence of the outside on lignite, and can better reduce the moisture in the lignite and remove the ash, and increase the calorific value;

2, compact structure, small footprint, the heat required for drying is mainly provided by the hollow blade wall surface arranged on the hollow shaft, the heat transfer oil enters the hollow shaft of the double paddle dryer from the heat transfer oil furnace, and then enters the hollow shaft In the hollow hollow blade, the hollow blade is continuously stirred and contacted with lignite to dry the lignite, and the heat transfer amount of the jacket wall is only a small part, so the heat transfer surface of the unit volume device is large, which can save The footprint of the installation reduces infrastructure investment;

3. The safety of the twin-screw drying device is good. Because the atmosphere of the external oxygen is dry, the drying of the lignite of the flammable material will not cause fire or dust explosion.

4. High heat utilization rate and low operating cost. Since the heat required for drying is provided by the heat transfer oil rather than by the hot gas, the heat loss carried by the hot gas is reduced. Due to the compact structure of the double paddle dryer and the small number of auxiliary devices, the heat loss is also reduced, and the heat utilization rate can reach 80% - 90 % ;

5. The gas flow is small, and the loss of volatiles is reduced, and some auxiliary equipment can be reduced or omitted accordingly. Since no gas is required for heating, the amount of gas used in the drying process is greatly reduced. The gas flow rate in the dryer is low, and the dust emitted by the gas is less;

6. The material has wide adaptability and the product is evenly dried. Since the rotation speed of the two shafts is controllable, the time of material retention can be controlled. Therefore, in actual use, the residence time of the materials in the dryer can be adjusted according to the nature of the materials and the drying conditions to adapt to difficult materials and high moisture materials. Drying requirements; 7. The adjustment range is large, the conditions are loose, and the control is convenient and fast. The feeding speed, the rotation speed of the shaft and the temperature of the heat transfer oil can be separately adjusted and controlled, so that the drying conditions suitable for the material characteristics are established in terms of material drying time, drying temperature, drying form, etc., satisfying the drying standard, than the fluidized bed. The operation of drying and air drying is easy to control and can be applied to various operations;

8, the exhaust gas displacement is small, easy to handle.

Referring to FIG. 4, FIG. 5, FIG. 6, and FIG. 7, the structure of the fin reforming device in step 3) of the embodiment includes: a casing, a feeding hopper above the casing, and a discharging hopper 3 disposed under the casing. , a heat conducting mechanism 4 disposed in the outer casing, and an exhaust mechanism 5 disposed substantially in the middle of the outer casing.

The heat transfer mechanism 4 includes a lead-out manifold 41 for discharging a heat-conducting medium disposed at the feed hopper 2, a plurality of heat-conducting medium lead-out portions 43 connected to the lead-out manifold 41, and a heat transfer medium for being introduced at the discharge hopper 3. The medium introduction manifold 42 and the plurality of heat transfer medium introduction portions 44 connected to the introduction header are connected to the plurality of heat transfer tubes 45 between the introduction portion and the lead portion, and the heat transfer medium introduction portion 44 and the heat transfer medium corresponding thereto are disposed. a portion 43 and a plurality of heat transfer tubes 45 disposed between them to form a heat transfer unit, wherein the plurality of heat transfer tubes 45 in each heat transfer unit are uniformly arranged in parallel directions and intervals; materials are formed between the heat transfer tubes The mobile space. A plurality of fins 46 are disposed between the heat conducting tubes 45 in the longitudinal direction. The fins 46 are inclined downwardly at a certain angle in the vertical direction, and the angle of the tilting may be greater than 0 degrees and less than or equal to 45 degrees. Choose between the range. The cross-sectional shape of the heat transfer tube 45 in this embodiment is a square shape, and in other embodiments, it may be set to a circular or elliptical shape or other polygonal shape. The fins in this embodiment are divided into a first fin 46a and a second fin 46b. Wherein, the first fins 46a are arranged in parallel in the longitudinal direction, and are integrally disposed in the space between the adjacent two heat pipes, integrally connected with the adjacent two heat pipes, and the lower end thereof is away from the exhaust channel. Tilting, blocking the exhaust port 54 disposed on the exhaust passage near the wall of the heat pipe, so that the gas is discharged from the exhaust port 54 under the action of internal negative pressure, and the solid material remains in the casing under the blocking of the fin Therefore, the primary fin 46a is provided, and its main function is to facilitate the exhaust, and of course, also plays a certain role in turning. In the embodiment, the first-stage fins are arranged in such a manner that each of the first-stage fins at the same height forms a funnel-shaped blanking space with a large diameter and a small diameter. When the material falls, the material is concentrated first, then diffused, and then When the fins of the next height are spread out, the fins are dynamically flipped, so that the heat can be uniformly transferred, so that the materials in the outer shell can be processed at a suitable temperature. Get high quality coal products. Figure 4 As shown in the embodiment, the upper end portion of the secondary fin 46b is connected to an adjacent pair of heat transfer tubes, and the lower end portion protrudes beyond the space between the pair of adjacent heat transfer tubes, that is, the pair of heat conduction is extended. In the blanking space between the tube and the four heat pipes adjacent to the pair of heat pipes, the secondary fins 46b are also disposed adjacent to the pair of heat pipes, and the lower ends of the second fins 46b are also offset from the vertical direction. Enter this blanking space. The main function of the secondary fins 46b is to strengthen the turning and heat conduction, so that the heat generated by the heat transfer tubes can be transmitted to the blanking space between the heat conducting tubes, and the temperature of the materials in the blanking space between the heat conducting tubes tends to In the same way, the gases generated by the materials in the various places can be discharged faster.

Wherein, a plurality of fins are also disposed between the heat-conducting medium introduction portions, so that the materials can be flipped and transferred when they reach the space between the heat-conducting medium introduction portions, so that the gas generated at the place can be discharged in time while maintaining heat transfer. Evenly.

A central exhaust passage 51 is disposed at a center of the outer casing, and an outer annular heat transfer pipe is provided with an annular exhaust passage 52. The annular exhaust passage 52 and the central exhaust passage 51 pass through an exhaust manifold and an exhaust end 53. Connected to discharge the gas. It can be seen from Fig. 3 that the central exhaust passage penetrates all the way to the position where the heat transfer medium is introduced, so that the gas generated at the heat transfer medium introduction portion can be discharged. Among them, the upper end of the exhaust manifold and the upper end of the central exhaust passage are all pointed, and this structure is advantageous for the falling of the material. An upper exhaust port 6 is provided in the vicinity of the casing near the feed hopper for discharging steam generated by the coal into the casing.

The feed hopper 2 includes an upper feed section 21, a middle feed section 22, and a lower feed section 23 disposed in the longitudinal direction, wherein the diameter of the middle feed section 22 is smaller than that of the upper feed section 21 and the lower feed section 23. The upper feed section 21 is gradually reduced from top to bottom, and the lower feed section 23 is gradually increased from top to bottom, and the feed hopper 2 arranged in such a structure can block the gas and strengthen the change. Quality effect.

The discharge hopper 3 comprises an upper discharge section 31 and a lower discharge section 32, and the upper discharge section 31 is composed of a plurality of horizontally arranged distribution hoppers. This arrangement can make the discharge uniform, and does not cause the discharge jam. The situation of coal quality. The water outlet wall is arranged outside the lower discharge section 32, and the cooling water circulation is realized by the inlet pipe and the outlet pipe, thereby reducing the discharge temperature, so that the device for the next treatment of the discharge is not damaged by contact with the high temperature material. In addition, the set hopper can also play a transitional role, avoiding the high temperature material directly contacting the water wall of the lower discharge section. The fin modification device in this embodiment further includes a temperature control mechanism disposed at the feed hopper, and includes:

a temperature sensor (not shown) acquires a temperature signal at each heat transfer medium deriving portion; the controller compares the temperature signal with a preset temperature value, and issues a temperature control command according to the comparison result;

The regulating valve 7 provided in the outlet of each heat conducting unit adjusts the opening according to the temperature control command.

By setting this temperature control mechanism, the temperature in each of the various outer casings can be adjusted in time to make them consistent, and the temperature is consistent with the set temperature, thereby ensuring the expected product.

The heat transfer medium deriving portion 43 has a straight shape as a whole, and has a certain inclination at the top thereof, and has a pointed shape. This arrangement can make the blanking smoother.

The heat transfer medium introduction portion 44 has a straight shape as a whole, and has a certain inclination at the top thereof, and has a pointed shape to facilitate blanking.

In this embodiment, only the two-stage exhaust passages of the central exhaust passage and the peripheral exhaust passage are provided. In the actual implementation process, according to the number of the heat-conducting tubes provided, from the center of the outer casing, more levels can be set. The exhaust passage allows the gas generated during the heating process to be discharged in time without affecting the reforming effect.

In this embodiment, each component is disposed toward a target that facilitates blanking and facilitates exhaust gas exhaustion, thereby enabling the temperature of materials in various materials in the blanking space to be flexibly and effectively controlled during the process of treating coal. To achieve a good processing effect. In this embodiment, the heat transfer medium is made of a hot gas.

The twin-screw drying device and the fin reforming device used in the embodiment treat the lignite. In other embodiments, the tunnel kiln, the fluidized bed furnace, the suspension roaster, the rotary kiln, the dryer, etc. can also be used for heating modification. Quality device.

In other embodiments, other organic or inorganic binders, or a composite binder formed by mixing organic and inorganic bonding machines, or a composite binder formed of two or more organic binders may be used. Or a composite binder formed of two or more inorganic binders.

The powdered lignite raw coal used in the above examples and the modified coal obtained by the above examples were tested. The test results and analysis results are shown in Table 1. Table l test results

It can be seen from Table 1 that after the drying treatment at 300 ° C in step 1), the total water and volatile matter of the lignite are greatly reduced, the fixed carbon content is increased, and the step 4) is changed at 650 °. After the quality treatment, the modified pellets have a higher heat value than the previous 300 °C modified coal, the total water and volatiles are greatly reduced, the fixed carbon content is greatly increased, and the low heat is compared with the raw coal. The value has increased by more than 2 times, and almost all of the water has been removed.

In the entire upgrading process in this embodiment, by calculating the weight of the feed and the weight of the discharge and the weight of the obtained condensed water, the drying treatment at 300 ° C in the step 1) is obtained in the present embodiment. The obtained lignite was dry-distilled at 650 ° C, the weight loss rate reached 21.8%, the yield of condensed water was also large, reaching 26.01%, and the weight ratio of feed to discharge was 1.92.

Embodiment 2

1) The powdered lignite is heated and dried in a twin-screw drying device to remove moisture, and the heating temperature is 200 ° C, and the temperature is kept for 3 hours;

2) Then, the lignite obtained by the step 1) is naturally cooled to 80 ° C, and discharged;

4) Put the pellet into the fin modification device, heat it to 700 ° C, and then keep it for 2.5 hours. The obtained modified coal was cooled to 100 ° C and discharged.

In the step 3), the ratio of the lignite to the binder is: 50 parts of lignite and 50 parts of binder.

The binder is made up of 15 parts of a PVFM solution, 4 parts of sodium humate, and 81 parts of water. The PVFM solution comprises: 5 parts of polyvinyl alcohol, 3 parts of formic acid, and 92 parts of water.

Embodiment 3

1) The powdered lignite is heated and dried in a twin-screw drying device, and the water is removed, and the heating temperature is 300 ° C, and the temperature is kept for 2.5 hours;

2) Then the step 1) the treated lignite is naturally cooled to 100 ° C, and discharged;

4) The pellet was charged into a fin reforming apparatus, heated to 650 ° C, and then incubated for 4 hours, and the obtained modified coal was cooled to 100 ° C to discharge.

In the step 3), the ratio of the lignite to the binder is: 80 parts of lignite and 30 parts of binder.

The binder is made up of 30 parts of PVFM solution, 2 parts of sodium humate, and 68 parts of water, wherein the PVFM solution comprises: 2 parts of polyvinyl alcohol, 3 parts of formic acid, and 95 parts of water.

Embodiment 4

1) The powdered lignite is heated and dried in a twin-screw drying device, and the water is removed, and the heating temperature is 280 ° C, and the temperature is maintained for 1.5 hours;

2) Then, the lignite obtained in the step 1) is naturally cooled to 90 ° C, and discharged;

4) The pellet was charged into a fin reforming apparatus, heated to 900 ° C, and then incubated for 3 hours, and then the obtained modified coal was cooled to 100 ° C to discharge.

In the step 3), the ratio of the lignite to the binder is: 99 parts of lignite and 1 part of binder. The binder is made up of 15 parts of PVFM solution, 4 parts of sodium humate, and 81 parts of water. The PVFM solution includes: 6 parts of polyvinyl alcohol, 1.5 parts of formic acid, and 92.5 parts of water.

Embodiment 5

1) The powdered lignite is heated and dried in a twin-screw drying device to remove moisture, and the heating temperature is 280 ° C, and the temperature is kept for 2.5 hours;

4) The pellet was charged into a fin reforming apparatus, heated to 900 ° C, and then incubated for 2.5 hours, and then the obtained reformed coal was cooled to 100 ° C to discharge.

In the step 3), the ratio of the lignite to the binder is: 60 parts of lignite and 25 parts of binder.

The binder is made up of 17 parts of PVFM solution, 3 parts of sodium humate, and 80 parts of water. The PVFM solution includes: 4 parts of polyvinyl alcohol, 2 parts of formic acid, and 94 parts of water.

Embodiment 6

1) The powdered lignite is heated and dried in a twin-screw drying device, and the water is removed, and the heating temperature is 280 ° C, and the temperature is kept for 2.5 hours;

2) when the lignite obtained in the step 1) is naturally cooled to 90 ° C, discharging;

4) The pellet was charged into a fin reforming apparatus, heated to 900 ° C, and then held for 2.5 hours, and then the obtained lignite was cooled to 100 ° C to discharge.

In the step 3), the ratio of the lignite to the binder is: 70 parts of lignite and 15 parts of binder.

The binder is made up of 25 parts of a PVFM solution, 2 parts of sodium humate, and 73 parts of water. The PVFM solution includes: 5 parts of polyvinyl alcohol, 3 parts of formic acid, and 92 parts of water. The present invention has been described in detail above, and the principles and embodiments of the present invention have been described by way of specific examples. The description of the above embodiments is only for the purpose of understanding the method of the present invention and its core idea. It should be noted that those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the invention.

Claims

Rights request

A process for treating powdered lignite, characterized in that it comprises the following steps:

1) heating the powdered lignite to 100 ° C ~ 1000 ° C, and then heat lh ~ 5h;

2) cooling the lignite obtained in the step 1) to below 100 ° C;

3) adding the binder and stirring to form the hook;

4) Heat the lignite after molding to 100 ° C ~ 1000 ° C, heat lh ~ 5h.

2. The process for treating powdery lignite according to claim 1, wherein in step 1), the powdered lignite is heated to 250 ° C to 350 ° C and then held for 2 h to 2.5 h.

3. The treatment process of powdered lignite according to claim 1, wherein in step 1), the powdered lignite is heated to 300 ° C and then incubated for 2 h.

4. The process for treating powdery lignite according to claim 1, wherein in step 4), the mixture is heated to 300 ° C to 800 ° C, and then insulated for 2 h to 4 h.

5. The process for treating powdered lignite according to claim 1, wherein in step 4), heating to 650 ° C, followed by holding for 2 h.

6. The process for treating powdered lignite according to claim 1, wherein in step 2), cooling by natural cooling or forced cooling is employed.

The process for treating powdery lignite according to claim 1, wherein the powdery lignite has a particle diameter of 5 mm or less.

The process for treating powdery lignite according to claim 1, wherein the powdery lignite has a particle diameter of 2 mm or less.

9. The process for treating powdered lignite according to claim 1, wherein in step 3), the ratio of binder to lignite is: 50 to 99 parts of lignite, binder 1~ 50 copies.

The process for treating powdery lignite according to claim 1, wherein in step 3), the ratio of binder to lignite is: 60 to 90 parts of lignite, binder 10~

40 copies.

The process for treating powdery lignite according to claim 1, wherein in step 3), the ratio of binder to lignite is: 70 to 85 parts of lignite, binder 15~ 30 copies.

The process for treating powdery lignite according to claim 1, wherein in step 3), the ratio of the binder to the lignite is 80 parts by weight of lignite and 20 parts by weight of the binder.

13. The treatment process of powdered lignite according to claim 1, wherein the binder is an organic binder or an inorganic binder or an organic composite binder or an inorganic composite binder or organic- Inorganic composite binder.

The process for treating powdery lignite according to claim 1, wherein the binder is a tar pitch binder.

The process for treating powdery lignite according to claim 14, wherein the binder is any one or more of coal tar pitch, petroleum pitch, petroleum residue, coal tar, and tar residue. mixture.

The process for treating powdered lignite according to claim 1, wherein the binder is a polymer binder.

The process for treating powdery lignite according to claim 16, wherein the binder is any of polyethylene, polyvinyl alcohol, polystyrene, phenolic resin, synthetic resin, polyurethane, and resin latex. One.

The process for treating powdery lignite according to claim 1, wherein the binder is any one of starch or pulp waste liquid and biomass, and the biomass is crop waste.

The process for treating powdery lignite according to claim 18, wherein the crop waste is any one of wheat straw, straw, glutinous rice kernel, glutinous rice rod, wood chips, bark, and trunk.

The process for treating powdered lignite according to claim 1, wherein the binder is an inorganic binder.

The process for treating powdered lignite according to claim 20, wherein the binder is lime or cement or gypsum.

The process for treating powdered lignite according to claim 1, wherein the binder is a clay-based binder.

23. The process for treating powdered lignite according to claim 1, wherein the binder is sodium silicate.

The process for treating powdery lignite according to claim 1, wherein the binder comprises 15 to 30 parts by weight of PVFM solution, 1-4 parts of sodium humate, and 66 to 85 parts by weight of water. The PVFM solution comprises: 2-6 parts of polyvinyl alcohol, 1.5-3 parts of formaldehyde, and 90-9 parts of water.

The process for treating powdery lignite according to claim 1, wherein the binder is made of 20 parts of PVFM solution, 2 parts of sodium humate, and 78 parts of water, wherein The PVFM solution includes: 4.85 parts of polyvinyl alcohol, 2.43 parts of formic acid, and 92.72 parts of water.

The process for treating powdery lignite according to claim 1, wherein in step 1) and step 3), heating of the powdered lignite is carried out in any one of the following devices: tunnel kiln, flow Chemical bed furnace, suspension roaster, rotary kiln, drying device, fin modification device.

The processing method of the powdered lignite according to claim 26, wherein the drying device is a twin-screw drying device, comprising two hollow shafts, wherein the hollow shaft is distributed with a plurality of hollow blades, and the heat conduction is The oil enters the hollow shaft and the cavity of the hollow blade, and the wall surface of the hollow blade is used as a heat transfer medium to modify the powdered lignite.

The processing method of the powdered lignite according to claim 26, wherein the fin reforming device comprises a casing, a feeding end and a discharging end respectively disposed at both ends of the casing, and from the center of the casing from the inside to the outside Providing at least two stages of exhaust passages, the exhaust passages being electrically connected to an exhaust end disposed on the outer casing; and a heat conducting mechanism disposed in the cavity between the feed end and the discharge end of the outer casing The heat conducting mechanism is provided with a heat conducting medium inlet near the discharging end, and a heat conducting medium outlet is arranged near the feeding end, the heat conducting mechanism comprises a plurality of sets of spaced apart heat conducting units, and the heat conducting unit comprises a plurality of heat conducting tubes, The heat pipe is connected to the heat transfer medium inlet and the heat transfer medium outlet, and the fins disposed between the adjacent pipes are inclined at a direction away from the exhaust passage to block the exhaust port opened on the wall surface of the exhaust passage.