A method for reducing the soil acidity of rare earth mines

Abstract

The present invention belongs to the technical field of rare earth mine restoration. The present invention discloses a method for reducing the acidity of rare earth mine soil, which comprises the following steps: preparing a repair agent: mixing raw materials to obtain a repair agent, and the raw materials include the following components by weight: 15 parts of vegetable oil cake powder, 30 parts of steel slag, and 50 parts of phosphogypsum powder; surface finishing of rare earth mines: setting a repair zone with a width of 5-8 m, a manure conversion zone of 0.5 m-1 m on both sides in each repair zone, and diversion ditches reserved at the two side edges of each reserved zone, and there is an aisle between adjacent repair zones; laying sludge in the manure conversion zone, without laying sludge at the diversion ditch, and the repair agent is mixed in the sludge; releasing soil-loosening animals or microorganisms on the sludge, covering with animal manure, and then pressing a heat-insulating layer; planting plants in the manure conversion zone; the plants are heavy metal ion-enriching plants; digging the aisle 3-5 m deep, laying a leaching pipeline and filling it with new external soil, and the leaching pipeline is provided with a plurality of branch pipes, and the upper ports of the branch pipes are arranged below the sludge conversion zone. The repair method of the present invention can repair heavy metal ions and acidity simultaneously.

Description

Technical Field

[0001] The present invention relates to the technical field of mine restoration, and specifically relates to a method for reducing the acidity of soil in rare earth mines. Background Art

[0002] The description of the background art in the present invention belongs to the related art related to the present invention, and is only used to illustrate and facilitate the understanding of the content of the present invention, and should not be understood as the applicant clearly believing or presuming that the applicant believes it is the prior art on the filing date of the first application of the present invention.

[0003] Acidic soil not only has the weakness of low availability of effective nutrients such as calcium, nitrogen, phosphorus, and potassium, but also has the disadvantages of easy hardening, poor moisture retention and air permeability, and is likely to cause difficulties in the development and extension of crop roots. During the process of soil fertilization and cultivation, sulfate radicals left by the decomposition of chemical fertilizers accelerate soil acidification. During straw returning to the field, organic acids generated during the decomposition of organic matter in straw tend to accelerate soil acidification, restricting and limiting the sustainability of the straw returning to the field technology for soil fertility improvement and yield increase on acidic soil. Therefore, if a soil improvement material that can overcome the disadvantages of chemical fertilizers, increase the effective fertility of soil such as calcium, nitrogen, phosphorus, and potassium, weaken the tendency of soil acidification during straw returning to the field, improve the moisture retention and air permeability of acidic soil, and reduce the acidity of the soil can be invented, the purpose of improving acidic soil and increasing crop yield can be achieved, and it has a positive significance for the sustainability of directly adopting the straw ploughing and returning to the field cultivation technology. Summary of the Invention

[0004] The purpose of the embodiment of the present invention is to provide a method for reducing the acidity of soil in rare earth mines, which can reduce soil acidity and heavy metal ions simultaneously.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A method for reducing the acidity of soil in rare earth mines includes the following steps:

[0007] Prepare a repair agent: Mix raw materials to obtain a repair agent. The raw materials include the following components by weight: 15 parts of vegetable oil cake meal, 30 parts of steel slag, and 50 parts of phosphogypsum powder;

[0008] Surface finishing of rare earth mines: Set repair belts with a width of 5 - 8 m, and a manure conversion area of 0.5 m - 1 m on both sides in each repair belt. Drainage ditches are reserved on both sides of each reserved area, and aisles are provided between adjacent repair belts;

[0009] Lay sludge in the manure conversion area, and do not add sludge at the drainage ditch. The sludge is mixed with the repair agent;

[0010] Throwing loose soil animals or microorganisms on the sludge, covering it with animal feces, and then pressing it with a heat-insulating layer;

[0011] Planting plants in the manure conversion area; the plants are heavy metal ion-enriching plants;

[0012] The passage is dug 3-5m deep, and after laying the leaching pipe, it is filled with new soil. The leaching pipe is provided with a plurality of branch pipes, and the upper end of the branch pipe is arranged below the sludge conversion zone.

[0013] Furthermore, the heavy metal ion-accumulating plant is at least one of Chenopodium album, Setaria viridis, Chlorophytum corydalis, Humulus foetida, Goose down vine, wild watermelon seedling, Leonurus japonicus, Chamomile and Prickly lettuce.

[0014] Furthermore, the growth environment factors of the plants in the manure conversion area are monitored in real time, and the environmental factors include soil temperature, soil salinity, soil dissolved oxygen, soil humidity and light intensity.

[0015] Furthermore, the environmental factors are monitored in real time using sensors, and the sensors are connected to a control system. When the monitored values ​​of the environmental factors exceed a preset range, the control system adjusts the corresponding environmental factors according to a preset plan.

[0016] Furthermore, the control system is provided with an alarm system, and when the number of environmental factors exceeding the threshold is greater than one, the alarm system sounds an alarm.

[0017] Furthermore, the alarm system uses voice alarm or warning text alarm.

[0018] Furthermore, when the heavy metal ion-enriched plants grow to the growth stage, they are sprayed with plant growth inhibitors, and when the heavy metal ion-enriched plants grow to the maturity stage, they are sprayed with heavy metal pollution remediation promoters, and the plants are harvested during the senescence stage to achieve the removal of heavy metal pollution;

[0019] The plant growth inhibitor is a mixture of cyanogen and glufosinate ammonium, wherein the spraying mass concentration of cyanogen is 0.1-0.5%; the spraying mass concentration of glufosinate ammonium is 0.01-0.1%;

[0020] The heavy metal pollution remediation accelerator is thiourea, which is used together with an auxiliary bonding agent commonly used in pesticides during use, and the spraying mass concentration of thiourea is 0.8-1.2%.

[0021] The embodiments of the present invention have the following beneficial effects:

[0022] In the present invention, by mixing the repair agent with the sludge, during the growth process of plants, the repair agent in the sludge can be moved downward by watering the plants, and then the plant absorption ability can absorb heavy metal ions and acidic substances upward. The water can penetrate into the drainage pipes through the ditches on both sides of the sludge. The drainage pipes are arranged at longitudinal intervals, so that the repair agent can be further dispersed downward to achieve in-situ solidification in the deep layer.

[0023] In the present invention, by setting up a repair zone, it is convenient for operation. The sludge is used to realize waste utilization, and real-time monitoring is adopted to improve the repair efficiency and real-time performance. In the present invention, heavy metal ion-enriched plants are used to enrich heavy metal ions, and then the heavy metal ions are absorbed through plant growth, and then the metal ions in the soil are reduced by harvesting the plants. Detailed implementation mode

[0024] The following introduces the present application in combination with embodiments. In some embodiments of the present invention

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, in the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Different embodiments can be replaced or combined. For those of ordinary skill in the art, other implementation manners can also be obtained according to these embodiments without creative work.

[0026] A method for reducing the acidity of soil in rare earth mines, comprising the following steps:

[0027] Prepare a repair agent: Mix the raw materials to obtain a repair agent. The raw materials include the following components by weight: 15 parts of vegetable oil cake powder, 30 parts of steel slag, and 50 parts of phosphogypsum powder;

[0028] Surface finishing of rare earth mines: Set up a repair zone with a width of 5-8 m. There are manure conversion areas of 0.5 m-1 m on both sides in each repair zone. Water diversion ditches are reserved at the two side edges of each reserved area, and there is an aisle between adjacent repair zones;

[0029] Lay sludge in the manure conversion area. No sludge is added at the water diversion ditch. The repair agent is mixed in the sludge;

[0030] Release soil-loosening animals or microorganisms on the sludge, cover with animal manure, and then press a heat preservation layer;

[0031] Plant plants in the manure conversion area; the plants are heavy metal ion-enriched plants;

[0032] Dig the aisle 3-5 m deep, lay leaching pipes and fill it with new external soil. The leaching pipes are provided with a plurality of branch pipes, and the upper ports of the branch pipes are arranged below the sludge conversion area.

[0033] In some embodiments of the present invention, the heavy metal ion-accumulating plant is at least one of Chenopodium album, Setaria viridis, Chloris viridis, Humulus foetida, Goosefoot vine, Wild watermelon seedling, Motherwort, Chamomile, and Prickly lettuce.

[0034] In some embodiments of the present invention, the growth environmental factors of the plants in the manure conversion area are monitored in real time, and the environmental factors include soil temperature, soil salinity, soil dissolved oxygen, soil humidity and light intensity.

[0035] In some embodiments of the present invention, the real-time monitoring of the environmental factors is performed by sensors, and the sensors are connected to a control system. When the monitoring value of the environmental factors exceeds a preset range, the control system adjusts the corresponding environmental factors according to a preset plan.

[0036] In some embodiments of the present invention, the control system is provided with an alarm system, and when the number of environmental factors exceeding a threshold is greater than one, the alarm system sounds an alarm.

[0037] In some embodiments of the present invention, the alarm system uses voice alarm or warning text alarm.

[0038] In some embodiments of the present invention, when the heavy metal ion-enriched plants grow to the growth stage, they are sprayed with plant growth inhibitors, and when the heavy metal ion-enriched plants grow to the maturity stage, they are sprayed with heavy metal pollution remediation promoters, and the plants are harvested during the senescence stage to achieve the removal of heavy metal pollution;

[0039] The plant growth inhibitor is a mixture of cyanogen and glufosinate ammonium, wherein the spraying mass concentration of cyanogen is 0.1-0.5%; the spraying mass concentration of glufosinate ammonium is 0.01-0.1%;

[0040] The heavy metal pollution remediation accelerator is thiourea, which is used together with an auxiliary bonding agent commonly used in pesticides during use, and the spraying mass concentration of thiourea is 0.8-1.2%.

[0041] The embodiments of the present invention have the following beneficial effects:

[0042] The present invention mixes the repair agent with the sludge. During the growth of plants, the repair agent in the sludge can be moved downward by watering the plants. The heavy metal ions and acidic substances are then absorbed upward by the plants' absorption capacity. The water can penetrate into the drainage pipes through the ditches on both sides of the sludge. The drainage pipes are arranged in a longitudinally spaced manner, so that the repair agent can be further dispersed downward to achieve in-situ solidification at a depth.

[0043] The present invention facilitates operation by setting a repair belt, realizes waste utilization by using sludge, and improves the repair efficiency and real-time performance by using real-time monitoring. The present invention uses heavy metal ion enrichment plants to enrich heavy metal ions, then absorbs heavy metal ions through plant growth, and then reduces metal ions in the soil by harvesting the plants.

[0044] Example 1

[0045] A method for reducing the acidity of rare earth mine soil comprises the following steps:

[0046] Preparation of a repairing agent: mixing raw materials to obtain a repairing agent, wherein the raw materials include the following components by weight: 15 parts of vegetable oil cake powder, 30 parts of steel slag and 50 parts of phosphogypsum powder;

[0047] Rare earth mine surface preparation: set up a restoration zone with a width of 5m, with a manure conversion zone of 0.5m-1m on both sides of each restoration zone, and a diversion ditch is reserved on both sides of each reserved area, and aisles are set between adjacent restoration zones;

[0048] Sludge is laid in the manure-sewage conversion area, no sludge is added in the diversion ditch, and the sludge is mixed with the repair agent; the sludge is urban sludge, which can realize waste utilization.

[0049] Loose animals or microorganisms are thrown onto the sludge, covered with animal feces, and then pressed with an insulation layer; the microorganisms can be acidophilic microorganisms, which can allow acidic substances to move upward.

[0050] Planting plants in the manure conversion area; the plants are heavy metal ion-enriching plants;

[0051] The passage is dug 4 meters deep, and after laying the leaching pipe, it is filled with new soil. The leaching pipe is provided with a plurality of branch pipes, and the upper end of the branch pipe is arranged below the sludge conversion zone.

[0052] The heavy metal ion enrichment plants are Chenopodium album, Setaria viridis, and Chlorophytum corydalis, and are cultivated in three rows. Of course, different combinations of plants can have different effects, and the combined cultivation of plants with root depth gradients has better effects.

[0053] Real-time monitoring of soil temperature, soil salinity, soil dissolved oxygen, soil humidity and light intensity. When the monitored values ​​of the environmental factors exceed the preset range, the control system adjusts the corresponding environmental factors according to the preset plan.

[0054] In some embodiments of the present invention, the control system is provided with an alarm system, and when the number of environmental factors exceeding the threshold is greater than 1, the alarm system sounds an alarm. The alarm system uses voice alarm.

[0055] In some embodiments of the present invention, when the heavy metal ion-enriched plants grow to the growth stage, a plant growth inhibitor is sprayed on them. When the heavy metal ion-enriched plants grow to the maturity stage, a heavy metal pollution remediation promoter is sprayed on them. The plants are harvested during the senescence stage to achieve the removal of heavy metal pollution.

[0056] The plant growth inhibitor is a mixture of maleic hydrazide and glufosinate-ammonium. The spraying mass concentration of maleic hydrazide is 0.3%; the spraying mass concentration of glufosinate-ammonium is 0.05%.

[0057] The heavy metal pollution remediation promoter is thiourea. The thiourea is used in common with an auxiliary binding reagent commonly used in pesticides during the use process. The spraying mass concentration of thiourea is 1%.

[0058] It should be noted that the above embodiments can be freely combined as needed. The above introduction is only the preferred embodiments of the present invention and is not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for reducing the soil acidity of rare earth mines, characterized in that, it includes the following steps: Preparing a repair agent: Mixing raw materials to obtain a repair agent. The raw materials include the following components by weight: 15 parts of vegetable oil cake meal, 30 parts of steel slag, and 50 parts of phosphogypsum powder; Surface finishing of rare earth mines: Set a repair zone with a width of 5 - 8 m. There are manure conversion zones on both sides within each repair zone, with a width of 0.5 m - 1 m. Drainage ditches are reserved on both sides of each reserved zone. There is an aisle between adjacent repair zones; Laying sludge in the manure conversion zones, without laying sludge at the drainage ditches. The sludge is mixed with the repair agent; Releasing soil - loosening animals or microorganisms on the sludge, covering with animal manure, and then pressing a heat - preservation layer; Planting plants in the manure conversion zones; the plants are heavy metal ion - enriched plants; Digging the aisle 3 - 5 m deep, laying leaching pipes and filling with new external soil. The leaching pipes are provided with multiple branch pipes, and the upper ports of the branch pipes are arranged below the sludge conversion zone; When the heavy metal ion - enriched plants grow to the growth stage, spraying a plant growth inhibitor on them. When the heavy metal ion - enriched plants grow to the maturity stage, spraying a heavy metal pollution repair promoter on them. Harvesting is carried out during the senescence stage of the plants to achieve the removal of heavy metal pollution; The plant growth inhibitor is a mixture of maleic hydrazide and glufosinate - ammonium. The spraying mass concentration of maleic hydrazide is 0.1 - 0.5%; the spraying mass concentration of glufosinate - ammonium is 0.01 - 0.1%; The heavy metal pollution repair promoter is thiourea. Thiourea is used in combination with a commonly used auxiliary binding reagent in pesticides during use. The spraying mass concentration of thiourea is 0.8 - 1.2%.

2. The method for reducing the soil acidity of rare earth mines according to claim 1, characterized in that, the heavy metal ion - enriched plants are at least one of Chenopodium album, Setaria viridis, Chloris virgata, Humulus scandens, Cynanchum chinense, Hibiscus trionum, Leonurus japonicus, Dendranthema lavandulifolium, Cirsium setosum.

3. The method for reducing the soil acidity of rare earth mines according to claim 1, characterized in that, the growth environmental factors of the plants in the manure conversion zones are monitored in real - time. The environmental factors include the temperature of the soil, the salinity of the soil, the dissolved oxygen of the soil, the humidity of the soil, and the light intensity.

4. The method for reducing the soil acidity of rare earth mines according to claim 3, characterized in that, the real - time monitoring of environmental factors is carried out by sensors. The sensors are connected to a control system. When the monitored values of the environmental factors exceed the preset range, the control system adjusts the corresponding environmental factors according to the preset plan.

5. The method for reducing the soil acidity of rare earth mines according to claim 4, characterized in that, the control system is provided with an alarm system. When the number of items exceeding the threshold in the environmental factors is greater than 1, the alarm system gives an alarm.

6. The method for reducing the soil acidity of rare earth mines according to claim 5, characterized in that, the alarm system uses voice alarm or warning text alarm.