RU2274749C1 - Method for land reclamation in the case of land corruption by opened deposit development - Google Patents

Abstract

FIELD: mining, particularly reclamation of surface-mined areas in agriculture and building industry.

SUBSTANCE: method involves selectively excavating, moving and accumulating ground layer and overburden in separate strip dumps; excavating open-pit field; filling and smoothing thereof and ground layer laying. After open-pit field excavation the excavated space is filled with building waste up to high ground water layer. The building waste has composition close to that of natural minerals with different fraction dimensions. The building waste is laid in several layers each having thickness of 40-60 cm. Each layer is compacted with soil compactors or compacting mechanism. Then draining layer is laid. The draining layer has particle dimensions of 150-200 mm and thickness of not less than 0.6 m. The draining layer is compacted by vibratory plates. Draining layer is covered with fertile ground so that fertile ground layer having thickness of not less than 0.3 m is created. Then straw layer in which chemical fertilizers and perennial grass seeds are added is formed over fertile ground layer. The straw layer is smoothed and sprinkled with dispersions containing water-soluble polymeric substances and synthetic water-soluble phosphates, wherein synthetic water-soluble phosphates are taken in amount of 1-4% by ready dispersion weight.

EFFECT: reduced labor inputs and reclamation work costs, improved land protection against wind erosion and scouring.

4 cl, 1 dwg

Description

The invention relates to the mining and processing industries and can be used to restore disturbed lands after open pit mining. A known method of restoring disturbed lands [1] during open-pit mining of deposits, including the excavation, movement and storage of soil layer and overburden in separate tape heaps, laying of the worked-out space layer-by-layer with dry rock with penetration in the roof of the foundation workings with subsequent additional laying of the hardening mixture. The disadvantage of this method is the high complexity, high cost and low adaptability of the work.

The closest technical solution, selected as a prototype, is a method of restoring disturbed lands during open-pit mining of deposits [2], including separate excavation, movement and storage of soil layer and overburden in separate tape dumps, mining of a quarry field, laying out of worked out space and its leveling overburden with subsequent laying of the soil layer.

The disadvantage of this method is the extraction of large volumes of soil to create a fertile layer, which in turn leads to the formation of large areas of disturbed land, an increase in labor costs and a significant increase in the cost of restoration work.

The present invention reduces labor costs and the cost of restoration work, and also protects the soil from wind and water erosion. To this end, a method of restoring disturbed lands during open-pit mining involves separate excavation, transfer and storage of soil layer and overburden into separate tape dumps, development of a quarry field, laying of the worked out space, its leveling and laying of the soil layer. Moreover, the laying of the worked-out space to the boundary of the upper groundwater level is carried out with construction waste that is close in composition to natural minerals with different particle sizes, layer by layer with a layer thickness of not more than 40-60 cm. Moreover, each layer is alternately compacted by packing with sealing machines or mechanisms, then lay a drainage layer with a thickness of at least 0.6 m and with a grain size of 150-200 mm fractions with compaction using vibrating plates, and a layer of potentially fertile soil with a thickness of up to the top of the drainage layer not less than 0.3 m, then a layer of straw is applied along with mineral fertilizers and seeds of perennial grasses, it is leveled, followed by spraying the soil with dispersions containing, together with water-soluble polymeric substances, natural and synthetic water-soluble phosphates. Moreover, the proportion of water-soluble phosphates in the dispersions is 1-4 wt.% Based on the finished dispersion. Dispersions have the ability to be absorbed into the soil and contribute to the formation of bound, firmly held and resistant to rains and weather changes crusts. The latter contributes to the emergence of a very good protective effect against erosion under the influence of rain and wind, since at the indicated dispersion rate in the soil there is no microporosity and no obstacles to plant development, as well as residual moisture is well retained. The implementation of this technical solution dramatically reduces the cost of restoration work through the use of construction waste resulting from the reconstruction, demolition and repair of buildings and structures, and there is no need to extract large volumes of soil to create a fertile layer. Considering the fact that building waste products are transported to landfills for household and industrial waste, the implementation of this invention will improve the environmental situation. Spraying the soil with dispersions makes it possible to solve the problem of covering disturbed lands with grass vegetation in a short time and at low cost, which means increasing soil resistance to water and wind erosion.

The drawing shows a diagram of the implementation of this method.

The method is as follows.

Initially, planning works are performed on the area of the disturbed site. The average absolute mark (ground level) is set taking into account the feasibility study. Territory planning is carried out with the planned surface giving a slight slope towards a general lowering of the earth's surface. Then proceed to the laying of the worked open pits 1, laying in layers 2, 3, 4, 5 construction waste with different particle sizes. Moreover, each laid layer is compacted by rolling with sealing machines and mechanisms and it should be no more than 40-60 cm. Laying of layers is carried out to the upper boundary of the groundwater level 6. Then a drainage layer 7 is laid from sand and gravel soil with a grain size of 150- 200 mm and a layer thickness of at least 0.6 meters, followed by compaction using vibrating plates. At the top of the drainage layer, layer 3 is poured from potentially fertile soil with a thickness of at least 0.3 meters, depending on the further use of the restored area. For landscaping this area, layer 9 is applied from the top of layer 8 of wheat straw cutting, which is applied together with mineral fertilizers and seeds of perennial cereal plants. After that, the straw layer is sprayed with an aqueous dispersion containing 30% of a synthetic substance and 2% of a mixture of different equal parts of sodium tripolyphosphate and sodium hexametaphosphate. A dispersed synthetic substance, for example, is a copolymer product derived from 40% vinyl acetate, 40% dioctyl maleate, 20% ethyl hexyl acrylate. As a result of this, such a spectacular and durable gluing of the layer occurs that for a long time it is possible to produce landscaping. As construction waste, you can use fired brick, concrete, reinforced concrete, ceramic tile battle. The draining layer can also be laid out of construction waste, having previously crushed it to the size of the battle within 150-200 mm. When using construction waste, it is necessary to exclude the ingress of organic waste into them in order to exclude suppuration and gas evolution.

Information sources

1. USSR copyright certificate No. 1062392, cl. E 21 C 41/00, 1983

2. Patent of Russia No. 2109427, cl. A 01 B 19/02, 1998

Claims (4)

1. A method of restoring disturbed lands during open pit mining, including separate excavation, transfer and storage of soil layer and overburden into separate tape heaps, development of a quarry field, laying, worked out space, leveling and laying of the soil layer, characterized in that the laying of worked out the spaces to the boundary of the upper groundwater level are produced by construction waste that is close in composition to natural minerals with different particle sizes, yoyno with a layer thickness of not more than 40-60 cm, while each layer is successively sealed by packing with sealing machines or mechanisms, then a drainage layer is laid with a thickness of at least 0.6 m and with a grain size of 150-200 mm with compaction using vibrating plates, and a layer of potentially fertile soil with a thickness of at least 0.3 m is sprinkled on top of the drainage layer, then a straw layer is applied along with mineral fertilizers and seeds of perennial grasses, it is leveled, followed by spraying the soil with dispersions containing together with water-soluble natural and synthetic water-soluble phosphates with measured substances, the proportion of water-soluble phosphates in the dispersions being 1-4 wt.% based on the finished dispersion. 2. The method according to claim 1, characterized in that as building waste use beaten fired brick, concrete, reinforced concrete, ceramic tile. 3. The method according to claim 1, characterized in that the drainage layer is covered with construction waste. 4. The method according to claim 1, characterized in that the drainage layer is covered with sand and gravel.