Method for preparing high-concentration coal water slurry by blending dehydration products at pipeline coal conveying terminal

Abstract

The invention discloses a method for preparing high-concentration coal water slurry by blending dehydration products at a pipeline coal conveying terminal. The method comprises the following steps: S1, respectively storing centrifugal coal and filter-pressed coal into a centrifugal coal bunker and a filter-pressed coal bunker; s2, conveying the filter-press coal in the filter-press coal bunker to a first spiral receiving bin through a first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bunker to a second spiral receiving bin through a second belt conveyor; s3, feeding the filter-pressed coal into a first-stage kneading and mixing machine through a first belt weigher in a first spiral receiving bin, adding water and an additive, blending to obtain kneading and mixing slurry, conveying the kneading and mixing slurry to a kneading and mixing tank, pumping to a second-stage kneading and mixing machine, feeding centrifugal coal into the second-stage kneading and mixing machine through a second spiral receiving bin through a second belt weigher, adding water and an additive, and stirring to obtain a second-stage kneading and mixing machine; and preparing the coal water slurry. According to the method for preparing the high-concentration coal water slurry, the problem of high cost caused by long-distance conveying of raw material lump coal and construction of a slurrying production workshop when a long-distance user uses the coal water slurry is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of water-coal slurry preparation, and in particular relates to a method for preparing high-concentration water-coal slurry by blending dehydrated products at a pipeline coal transportation terminal. Background Art

[0002] As an effective supplement to railway and road transportation, pipeline coal transportation is the fifth mode of transportation after railway, road, water and air transportation. At present, the terminal utilization of pipeline coal slurry is to provide it to neighboring chemical users as gasification slurry after concentration and quality improvement, and to dehydrate to obtain clean coal (centrifugal coal, filter press coal) and sell it to power, metallurgy, building materials and other fields as raw material pulverized coal. In order to further promote the development of the pipeline coal transportation industry, it is urgent to enrich the utilization methods of pipeline terminal products. Since the long-distance transportation technology of high-concentration water-coal slurry pipeline is not yet mature, when long-distance users use water-coal slurry, they need to build large-scale pulping production workshops and purchase pulping equipment such as crushers, rod / ball mills, etc., which has a high investment cost. The direct concentration method of pipeline coal slurry is only suitable for neighboring chemical users. The present invention is aimed at long-distance users and invents a method for preparing high-concentration water-coal slurry by blending the dehydrated products of pipeline coal terminal. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing high-concentration water-coal slurry by blending dehydrated products at a pipeline coal transportation terminal, which solves the problem of high costs caused by the need to transport raw lump coal over long distances and build a slurry production workshop when using water-coal slurry for remote users.

[0004] The technical solution adopted by the present invention is a method for preparing a high-concentration water-coal slurry by blending a dehydrated product at a pipeline coal transportation terminal, comprising the following steps: S1. Store the centrifugal coal and filter press coal in the centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bin to the first spiral material receiving bin via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bin to the second spiral material receiving bin via the second belt conveyor; S3. The first spiral receiving silo measures the filter coal into the first-stage kneading machine through the first belt scale, adds water and additives for stirring, and prepares the kneading slurry. The kneading slurry is transported to the kneading tank and pumped to the second-stage kneading machine. The second spiral receiving silo measures the centrifugal coal into the second-stage kneading machine through the second belt scale, adds water and additives for stirring, and obtains high-concentration water-coal slurry.

[0005] The present invention is also characterized in that: The blending ratio of centrifugal coal and filter press coal in S3 is (65%~77%): (23%~35%).

[0006] In S3, the dosage ratio of the additive added in the primary kneader to the additive added in the secondary kneader is 1:1, and the total dosage of the additive is 1.5‰~3.0‰ of the dry basis coal.

[0007] The kneading slurry concentration in S3 is 50%~58%.

[0008] The concentration of S3 medium-high concentration coal water slurry is 64%~66%.

[0009] The beneficial effects of the present invention are: The present invention provides a method for preparing high-concentration water-coal slurry by blending dehydrated products of pipeline coal transportation terminals. Users of high-concentration water-coal slurry purchase centrifugal coal and filter press coal, which are dehydrated products of pipeline coal slurry, and blend them in a certain proportion. There is no need to build a large-scale pulping production workshop or purchase pulping equipment such as crushers and rod / ball mills. The pulping process is simple, the number of equipment put into use is small, and the construction and equipment investment costs are saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of a method for preparing high-concentration water-coal slurry by blending dehydrated products at a pipeline coal transportation terminal of the present invention. DETAILED DESCRIPTION

[0011] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0012] The present invention provides a method for preparing a high-concentration coal-water slurry by blending a dehydrated product at a pipeline coal transportation terminal. Figure 1 As shown, the following steps are included: S1. Store the centrifugal coal and filter press coal in the centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bunker to the first spiral material bunker via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bunker to the second spiral material bunker via the second belt conveyor. The spiral material bunker is used to evenly distribute and buffer the coal volume to ensure the continuity and stability of the production line; S3. The first spiral receiving bin measures the filter coal through the first belt scale and feeds it into the first kneading machine, adds water and additives for stirring, and prepares the kneading slurry. The kneading slurry is transported to the kneading tank and pumped to the second kneading machine. The second spiral receiving bin measures the centrifugal coal through the second belt scale and feeds it into the second kneading machine, adds water and additives for stirring, and obtains high-concentration water-coal slurry, which is stored in the finished product slurry tank and pumped to the gasification furnace and other production systems for utilization through the finished product slurry pump; the blending ratio of centrifugal coal to filter coal is (65%~77%): (23%~35%); the dosage ratio of the additives added in the first kneading machine to the additives added in the second kneading machine is 1:1, and the total dosage of the additives is 1.5‰~3.0‰ of the dry basis coal; the kneading slurry concentration is 50%~58%; the concentration of the high-concentration water-coal slurry is 64%~66%.

[0013] The materials with centrifugal coal moisture content of 18.39%, ash content of 9.84%, filter press coal moisture content of 26.47%, ash content of 15.36%, and additive concentration of 10% were selected for implementation. The raw material characteristics are shown in Table 1: Table 1 Characteristics of raw materials for preparing high concentration coal water slurry

[0014] Example 1 The method proposed in this embodiment for preparing high-concentration coal water slurry by blending the dehydrated products at the coal pipeline terminal is as follows: Figure 1 As shown, the following steps are included: S1. Store the centrifugal coal and filter press coal in the centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bin to the first spiral material receiving bin via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bin to the second spiral material receiving bin via the second belt conveyor; S3, according to the blending ratio of centrifugal coal and filter coal of 77%:23%, the speed is set to 1200r / min, stirring for 5min, the dosage ratio of the additive added in the primary kneading machine to the additive added in the secondary kneading machine is 1:1, and the dosage of the additive is 1.5‰, 2.0‰, 2.5‰, and 3.0‰ of the dry basis coal, respectively. The first spiral feed bin feeds the filter coal into the primary kneading machine through the first belt scale, adds water and additives for stirring, and modulates into kneading slurry, transports the kneading slurry to the kneading tank and pumps it to the secondary kneading machine. The second spiral feed bin feeds the centrifugal coal into the secondary kneading machine through the second belt scale, adds water and additives for stirring, and obtains a high-concentration water-coal slurry. The obtained high-concentration water-coal slurry is analyzed as follows: (1) Concentration analysis The concentration of the prepared high-concentration water-coal slurry was analyzed and the concentration was 64.52%, which met the needs of chemical users; (2) Ash analysis The ash content of the prepared high-concentration water-coal slurry was analyzed and the ash content was 10.97%, which meets the needs of chemical users; (3) Particle size analysis The particle size analysis of the prepared high concentration water-coal slurry is shown in Table 2: Table 2 Analysis of particle size distribution of high concentration coal water slurry

[0015] The results show that in high-concentration water-coal slurry, particles larger than 14 mesh account for 0.7%, which is 0.7% higher than the demand of chemical users; particles of -40 mesh account for 86.06%, which is 1.06% higher than the demand; particles below -200 mesh and -325 mesh account for 34.69% and 27.74% respectively, and the particle size ratios are all within the range of chemical user demand.

[0016] (4) Analysis of the effects of different additive dosages on the viscosity of high-concentration coal water slurry The viscosity of the prepared high-concentration coal-water slurry under the influence of different additive dosages is analyzed, as shown in Table 3: Table 3 Analysis of the effects of different additive dosages on the viscosity of high-concentration coal water slurry

[0017] The results show that when the additive dosage is between 1.5‰ and 3‰, the viscosity of high-concentration water-coal slurry is less than 1200 mPa·s, which meets the needs of chemical users. When the additive dosage is 2‰, the viscosity of the coal slurry is 559.7 mPa·s, which can ensure good fluidity of the slurry while reducing the additive dosage and the pulping cost.

[0018] (5) Stability analysis The stability of water-coal slurry is analyzed by the water separation rate method. The water separation rate of water-coal slurry is the ratio of the supernatant liquid of the coal slurry to the total volume of the slurry. The smaller the water separation rate of the water-coal slurry, the better the slurry stability. Through the analysis of water-coal slurry, as shown in Table 4: Table 4 High concentration coal water slurry stability analysis table

[0019] The results show that the stability of high-concentration water-coal slurry meets the needs of chemical users after standing for 12, 24, 36, and 48 hours. In summary, the prepared high-concentration water-coal slurry meets the needs of chemical users in all aspects.

[0020] Example 2 The method proposed in this embodiment for preparing high-concentration coal water slurry by blending the dehydrated products at the coal pipeline terminal is as follows: Figure 1 As shown, the following steps are included: S1. Store the centrifugal coal and filter press coal in the centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bin to the first spiral material receiving bin via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bin to the second spiral material receiving bin via the second belt conveyor; S3, according to the blending ratio of centrifugal coal and filter coal of 71%:29%, the speed is set to 1200r / min, stirring for 5min, the dosage ratio of the additive added in the primary kneading machine to the additive added in the secondary kneading machine is 1:1, and the dosage of the additive is 1.5‰, 2.0‰, 2.5‰, and 3.0‰ of the dry basis coal, respectively. The first spiral feed bin feeds the filter coal into the primary kneading machine through the first belt scale, adds water and additives for stirring, and modulates into kneading slurry, transports the kneading slurry to the kneading tank and pumps it to the secondary kneading machine, and the second spiral feed bin feeds the centrifugal coal into the secondary kneading machine through the second belt scale, adds water and additives for stirring, and obtains a high-concentration water-coal slurry. The obtained high-concentration water-coal slurry is analyzed as follows: (1) Concentration analysis The concentration of the prepared high-concentration water-coal slurry was analyzed and the concentration was 64.70%, which met the needs of chemical users; (2) Ash analysis The ash content of the prepared high-concentration water-coal slurry was analyzed and the ash content was 11.45%, which meets the needs of chemical users; (3) Particle size analysis The particle size analysis of the prepared high concentration water-coal slurry is shown in Table 5: Table 5 Particle size distribution analysis of high concentration water-coal slurry

[0021] The results show that in high-concentration water-coal slurry, particles larger than 14 mesh account for 1.16%, which is 1.16% higher than user demand; particles below -40 mesh account for 79.43%, which is about 0.57% lower than the user requirement of 80-85%; particles below -200 mesh and -325 mesh account for 37.05% and 30.17% respectively, and the particle size proportions are all within the range of chemical user demand.

[0022] (4) Analysis of the effects of different additive dosages on the viscosity of high-concentration coal water slurry The viscosity of the prepared high-concentration coal-water slurry under the influence of different additive dosages is analyzed, as shown in Table 6: Table 6 Analysis of the effect of different additive dosages on the viscosity of high-concentration coal water slurry

[0023] The results show that when the additive dosage is between 1.5‰ and 3‰, the viscosity of high-concentration water-coal slurry is less than 1200 mPa·s, which meets the needs of chemical users. When the additive dosage is between 2.0‰ and 3.0‰, the fluidity is better.

[0024] (5) Stability analysis The stability of water-coal slurry is analyzed by the water separation rate method. The water separation rate of water-coal slurry is the ratio of the supernatant liquid of the coal slurry to the total volume of the slurry. The smaller the water separation rate of the water-coal slurry, the better the slurry stability. Through the analysis of water-coal slurry, as shown in Table 7: Table 7 High concentration coal water slurry stability analysis table

[0025] The results show that the stability of high-concentration water-coal slurry meets the needs of chemical users after standing for 12, 24, 36, and 48 hours. In summary, the prepared high-concentration water-coal slurry meets the needs of chemical users in all aspects.

[0026] Example 3 The method proposed in this embodiment for preparing high-concentration coal water slurry by blending the dehydrated products at the coal pipeline terminal is as follows: Figure 1 As shown, the following steps are included: S1. Store the centrifugal coal and filter press coal in the centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bin to the first spiral material receiving bin via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bin to the second spiral material receiving bin via the second belt conveyor; S3, according to the blending ratio of centrifugal coal and filter coal of 67%:33%, the speed is set to 1200r / min, stirring for 5min, the dosage ratio of the additive added in the primary kneader to the additive added in the secondary kneader is 1:1, and the dosage of the additive is 1.5‰, 2.0‰, 2.5‰, and 3.0‰ of the dry basis coal, respectively. The first spiral feed bin feeds the filter coal into the primary kneader through the first belt scale, adds water and additives for stirring, and modulates into kneading slurry, transports the kneading slurry to the kneading tank and pumps it to the secondary kneader, and the second spiral feed bin feeds the centrifugal coal into the secondary kneader through the second belt scale, adds water and additives for stirring, and obtains a high-concentration water-coal slurry. The obtained high-concentration water-coal slurry is analyzed as follows: (1) Concentration analysis The concentration of the prepared high-concentration water-coal slurry was analyzed and the concentration was 64.35%, which met the needs of chemical users; (2) Ash analysis The ash content of the prepared high-concentration water-coal slurry was analyzed and the ash content was 11.37%, which meets the needs of chemical users; (3) Particle size analysis The particle size analysis of the prepared high concentration coal water slurry is shown in Table 8: Table 8 Particle size distribution analysis of high concentration water-coal slurry

[0027] The results show that in high-concentration water-coal slurry, particles larger than 14 mesh account for 1.51%, 1.51% higher than user demand; particles below -40 mesh account for 79.78%, about 0.22% lower than the user requirement of 80-85%; particles below -200 mesh account for 40.99%, 0.99% higher than user demand; particles below -325 mesh account for 30.50%, and the particle size ratio is within the range of chemical user demand.

[0028] (4) Analysis of the effects of different additive dosages on the viscosity of high-concentration coal water slurry The viscosity of the prepared high-concentration coal-water slurry under the influence of different additive dosages is analyzed, as shown in Table 9: Table 9 Analysis of the effects of different additive dosages on the viscosity of high-concentration coal-water slurry

[0029] The results show that when the additive dosage is between 1.5‰ and 3‰, the viscosity of high-concentration water-coal slurry is less than 1200 mPa·s, which meets the needs of chemical users. When the additive dosage is between 2.5‰ and 3.0‰, the fluidity is better.

[0030] (5) Stability analysis The stability of water-coal slurry is analyzed by the water separation rate method. The water separation rate of water-coal slurry is the ratio of the supernatant liquid of the coal slurry to the total volume of the slurry. The smaller the water separation rate of the water-coal slurry, the better the slurry stability. Through the analysis of water-coal slurry, as shown in Table 10: Table 10 High concentration coal water slurry stability analysis table

[0031] The results show that the stability of high-concentration water-coal slurry meets the needs of chemical users after standing for 12, 24, 36, and 48 hours. In summary, the prepared high-concentration water-coal slurry meets the needs of chemical users in all aspects.

Claims

1. A method for preparing high-concentration coal-water slurry by blending dehydrated products at the terminal of pipeline coal transportation, characterized in that: The following steps are involved: S1. storing centrifugal coal and filter press coal in centrifugal coal bunker and filter press coal bunker respectively; S2, conveying the filter coal in the filter coal bin to the first spiral material receiving bin via the first belt conveyor, and conveying the centrifugal coal in the centrifugal coal bin to the second spiral material receiving bin via the second belt conveyor; S3. The first spiral receiving silo measures the filter coal into the first-stage kneading machine through the first belt scale, adds water and additives for stirring, and prepares the kneading slurry. The kneading slurry is transported to the kneading tank and pumped to the second-stage kneading machine. The second spiral receiving silo measures the centrifugal coal into the second-stage kneading machine through the second belt scale, adds water and additives for stirring, and obtains high-concentration water-coal slurry.

2. The method for preparing high-concentration coal water slurry by blending dehydrated products at the pipeline coal transportation terminal according to claim 1, characterized in that: The blending ratio of centrifugal coal and filter press coal described in S3 is (65%~77%): (23%~35%).

3. The method for preparing high-concentration coal water slurry by blending dehydrated products at the pipeline coal transportation terminal according to claim 1, characterized in that: The dosage ratio of the additive added in the primary kneader to the additive added in the secondary kneader in S3 is 1:1, and the total dosage of the additive is 1.5‰ to 3.0‰ of the dry basis coal.

4. The method for preparing high-concentration coal water slurry by blending dehydrated products at the pipeline coal transportation terminal according to claim 1, characterized in that: The kneading slurry concentration in S3 is 50% to 58%.

5. The method for preparing high-concentration coal water slurry by blending dehydrated products at the pipeline coal transportation terminal according to claim 1, characterized in that: The concentration of the water-coal slurry in S3 is 64% to 66%.

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