A method for mining and homogenizing stock alkali slag

Abstract

The present invention provides a method for excavating and homogenizing stock alkali slag, comprising the following steps: (1) dividing the excavation area: dividing the excavation area by exploration and calculation; (2) excavation process: excavating the stock alkali slag with the vertical direction as the cross section, and the excavated alkali slag is crushed and stored in multiple piles around the excavated unit; (3) alkali slag slurry homogenization process: hydraulic excavation of the stored alkali slag, wherein the hard block alkali slag absorbs water, expands and decomposes under the impact of the high-pressure water column, and the formed slurry flows into the excavated unit. The method provided by the present invention realizes precise excavation, and the excavated alkali slag is in a slurry form, which can be conveniently transported through a pipeline; and the slurry is evenly mixed and has uniform quality, thereby ensuring the continuous and stable operation of the subsequent alkali slag treatment system or the quality stability of the resource utilization product.

Description

Technical Field

[0001] The present invention relates to a process for excavating and homogenizing viscous industrial solid waste, and more particularly to a method for excavating and homogenizing stock alkali residue. Background Art

[0002] During the production of soda ash by the ammonia-soda process, about 10m3 of soda ash is produced per ton of soda ash. 3 The waste liquid, including approximately 0.3-0.6 tons of alkali residue, was stored without treatment in the area surrounding the alkali plant. Over the years, it has been difficult to naturally dry out, forming a "white sea." The alkali residue, formed over time, is a dark gray to off-white paste with a high moisture content (60%-70%). Its main components are inorganic substances such as calcium salts, magnesium salts, and sodium salts. Its particles are extremely fine, highly alkaline, viscous, and highly hygroscopic.

[0003] In order to improve the living environment and revitalize land resources, it is necessary to excavate the alkali slag in the alkali slag yard for disposal or resource utilization. However, since the main components of the stock alkali slag are substances such as calcium hydroxide and calcium carbonate, they are easy to harden after long-term storage, forming hard lumps that are difficult to break; at the same time, different production times lead to uneven properties of the stock alkali slag at different locations in the horizontal direction; the production process levels of different years lead to uneven properties of the stock alkali slag at different thicknesses in the vertical direction, and the soluble salt content varies greatly (10%-40%). This affects the continuous and stable operation of the alkali slag treatment system or the quality stability of resource utilization products. Therefore, it is necessary to ensure that the alkali slag after excavation is evenly mixed and the soluble salt content fluctuates little.

[0004] At present, conventional excavation equipment directly excavates and removes the alkali slag for disposal. The excavation capacity is small, some parts are in block form and the quality is uneven. The existing alkali slag is paste-like and viscous and cannot be directly sucked out by a pump. Direct excavation by suction dredgers causes large disturbances and uneven excavation concentration, which affects the stable operation of the subsequent disposal system. Summary of the Invention

[0005] Based on the above problems, this patent proposes a new method for mining and homogenizing the existing alkali slag, which can efficiently mine the existing alkali slag. The alkali slag after mining is in slurry form, evenly mixed, with uniform quality, and can be transported through pipelines.

[0006] The present invention provides a method for excavating and homogenizing stock alkali slag, comprising the following steps:

[0007] (1) Divide the excavation area: Divide the excavation area through exploration and calculation;

[0008] (2) Excavation process: The stock of alkali residue is excavated with the vertical direction as the cross section. The excavated alkali residue is crushed and stored in multiple piles around the excavated unit;

[0009] (3) Alkali slag slurry homogenization process: The stored alkali slag is subjected to high-pressure washing, wherein the hard blocky alkali slag absorbs water, expands and decomposes under the impact of the high-pressure water column, and the formed slag slurry flows into the mined unit.

[0010] According to the method provided by the present invention, the alkali slag after excavation is in a slurry form and can be conveniently transported through a pipeline; and the slurry is evenly mixed and has uniform quality, thereby ensuring the continuous and stable operation of a subsequent alkali slag treatment system or the quality stability of resource utilization products. DETAILED DESCRIPTION

[0011] The present invention provides a method for excavating and homogenizing stock alkali slag, comprising the following steps:

[0012] (1) Divide the excavation area: Divide the excavation area through exploration and calculation;

[0013] (2) Excavation process: Excavate the stock alkali residue with the vertical direction as the cross section. The excavated alkali residue is crushed and stored in multiple piles around the excavated unit;

[0014] (3) Alkali slag slurry homogenization process: The stored alkali slag is subjected to high-pressure washing, wherein the hard blocky alkali slag absorbs water, expands and decomposes under the impact of the high-pressure water column, and the formed slag slurry flows into the mined unit.

[0015] Wherein, in step (1), the step of dividing the excavation area includes:

[0016] The existing alkali slag storage yard was surveyed and sampled according to the grid distribution method, with a horizontal point spacing of 5 meters and a vertical point spacing of 1 meter. The soluble salt content at each point was tested to confirm the distribution of soluble salt in the storage yard, and the average soluble salt content a of the storage yard was calculated.

[0017] Based on the exploration results and calculations, the stockpile was divided into multiple units. Within each unit, alkali slag was excavated longitudinally along a vertical cross-section. After crushing and mixing, it was then stockpiled around the excavated unit. The soluble salt content (b) in the mixed alkali slag was equal to the average value (a). This method of dividing the excavation area was used in the examples.

[0018] In the present invention, it is preferred to use a long-arm excavator for excavation, and use the bucket provided with the long-arm excavator for crushing.

[0019] In step (3), the stored alkali residue is preferably subjected to high-pressure flushing by hydraulic excavation. The present invention has no particular requirements for the high-pressure pressure, as long as the hard, blocky alkali residue absorbs water, expands, and decomposes under the continuous impact of the high-pressure water column, and the formed slurry flows into the excavated unit. For example, the pressure can be 0.4-0.6MP.

[0020] In step (3), in order to ensure that the slurry flowing into the unit is fully mixed and uniform, and the content of soluble salts fluctuates slightly, it is preferred to set up multiple hydraulic flushing and excavation units to simultaneously flush the alkali slag stored around the unit in the opposite direction of the excavated unit, and the slurry formed by flushing flows into the unit. For example, two or four hydraulic flushing and excavation units can be set up.

[0021] Finally, a centrifugal slurry pump equipped with a buoyancy tank can be used to extract the slurry in the unit, and the extracted slurry is transported to the next process through a closed pipeline.

[0022] The present invention is described below by means of specific examples.

[0023] Example

[0024] A method for mining and homogenizing stock alkali slag comprises the following steps:

[0025] (1) Divide the excavation area: Divide the excavation area through exploration and calculation; specifically include:

[0026] 532 evenly distributed exploration points were selected from a 2-mu stock alkali slag dump. The soluble salt content in the alkali slag ranged from 10% to 40%, and the average soluble salt content in the alkali slag at all exploration points was calculated to be 25%.

[0027] According to the distribution of soluble salt content in the exploration, the yard was divided into multiple units through calculation, with the average soluble salt content of 25% as one mining unit.

[0028] (2) Use a long-arm excavator to vertically excavate the alkali slag in the unit within a range of 5-15 meters. After being crushed by the bucket of the long-arm excavator, it is piled horizontally around the excavation unit.

[0029] (3) Alkali slag slurry homogenization process: One mining unit is equipped with two sets of hydraulic flushing and excavation units. The alkali slag is flushed with high-pressure water columns in opposite directions at the same time. The slurry flows into the mined unit. Some of the undissolved large particles are immersed in water and continue to expand and analyze, and the soluble salts dissolve in the water.

[0030] By the method of the above steps (1)-(3), the stock alkali slag is accurately excavated. The alkali slag after excavation is in a slurry state, which can be extracted by a submerged centrifugal slurry pump and transported to the alkali slag treatment unit through a closed pipeline.

Claims

1. A method for mining and homogenizing stock alkali slag, characterized in that: The following steps are involved: (1) Divide the mining area: Divide the mining area through exploration and calculation; (2) Excavation process: Excavate the stock of alkali residue with the vertical direction as the cross section. The excavated alkali residue is crushed and stored in multiple piles around the excavated unit; (3) Alkali slag slurry homogenization process: The stored alkali slag is hydraulically excavated, wherein the hard blocky alkali slag absorbs water, expands and decomposes under the impact of the high-pressure water column, and the formed slag slurry flows into the mined unit; In step (1), the steps of dividing the excavation area include: Survey and sample the existing alkali slag storage yard using a grid-based sampling method, with a horizontal spacing of 4 meters and a vertical spacing of 0.5 meters. The soluble salt content at each point was tested to confirm the distribution of soluble salts in the storage yard and to calculate the average soluble salt content a in the storage yard. According to the exploration results and calculations, the stockpile is divided into multiple units. Alkali slag is excavated longitudinally in each unit with the vertical direction as the cross section, crushed and mixed, and stored around the excavated unit. The content b of soluble salt in the mixed alkali slag is equal to the average value a.

2. The method according to claim 1, characterized in that A long-arm excavator is used for excavation, and a bucket provided with the long-arm excavator is used for crushing.

3. The method according to claim 1, characterized in that In step (3), the stored alkali residue is hydraulically excavated by using a pressure pump equipped with a water gun.

4. The method according to claim 1 or 3, characterized in that In step (3), the high pressure is 0.4-0.6 MPa.

5. The method according to claim 1, wherein In step (3), multiple hydraulic flushing and excavation units are set up to simultaneously flush the alkali slag stored around the unit along the relative direction of the excavated unit, and the slag slurry formed by flushing flows into the unit.