Patent ID: 11959238
Assignee: NANJING INSTITUTE OF ENVIRONMENTAL SCIENCES, MEE
Field: Environmental technology (Chemistry)
Classification: CPC E  B  C  Y | IPC E

Claim 0:
1. A treatment method for a sandy soil landfill solid waste polluted river channel, wherein a treatment system for a sandy soil landfill solid waste polluted river channel is used; the treatment system includes a ground water interception and diversion system (1) and a river channel ecological remediation system (2);
the ground water interception and diversion system (1) comprises a water intake well (1-1) arranged upstream of ground water in a landfill area, a buffer pool (1-5) communicated with the water intake well (1-1), and a wastewater treatment system (1-6) communicated with the buffer pool (1-5); the water intake well (1-1), the buffer pool (1-5), and the wastewater treatment system (1-6) are communicated through a wastewater pipe (1-2); and an electric wastewater valve (1-3) and a variable frequency water pump (1-4) are arranged on the wastewater pipe (1-2) in sequence;
the river channel ecological remediation system (2) comprises an impermeable layer arranged at a bottom of a river channel and ecological bank protections arranged on both sides of a river channel slope; the impermeable layer comprises a clay cover layer (2-1) with a thickness of 50 to 55 cm, bentonite (2-2) with a thickness of 30 to 35 cm, and a High-Density Polyethylene (HDPE) film (2-3) with a thickness of 1.5 to 3 mm in sequence from top to bottom; the ecological bank protections comprise ecological slope protections (2-4) arranged on slopes on both sides, ecological prefabricated bricks (2-5) arranged on ecological slope protections (2-4) on both sides, and slope protection green plants (2-6) planted between two adjacent ecological prefabricated bricks (2-5) and on the surfaces of the ecological prefabricated bricks (2-5); the ecological prefabricated bricks (2-5) are made of ecological concrete; through holes are formed in the prefabricated bricks;
treatment steps of the treatment method are as follows:
S1, construction of ground water interception and diversion system (1),
S1-1, arranging the water intake well (1-1) upstream of the ground water in the landfill area to ensure that the ground water does not flow through the solid waste landfill area;
S1-2, pumping the ground water by using the water intake well (1-1), enabling the ground water to enter the buffer pool (1-5) through the wastewater pipe (1-2), the electric wastewater valve (1-3), and the variable frequency water pump (1-4) in sequence, monitoring the water quality by using an online water quality detection instrument arranged in the buffer pool (1-5), discharging the water into the river channel in a case that the water quality is up to standards, enabling the wastewater to enter the wastewater treatment system (1-6) in a case that the water quality is up to standards, and treating the wastewater and discharging the wastewater to the river channel after the wastewater is up to the standards;
S2, construction of river channel ecological remediation system (2),
laying the HDPE film (2-3), the bentonite (2-2), and the clay cover layer (2-1) at the bottom of the river channel in sequence from bottom to top;
S3, construction of bank protections,
splicing and fixing the ecological prefabricated bricks (2-5) to the ecological slope protections (2-4) to construct ecological bank protections, and planting the slope protection green plants (2-6) between two adjacent ecological prefabricated bricks (2-5) and on the surfaces of the ecological prefabricated bricks (2-5), wherein a preparation process for the ecological prefabricated brick (2-5) comprises the following steps:
1) uniformly mixing ecological concrete, an adhesive, an additive, humus, and water serving as raw materials in a mass ratio of 12 to 36:2:0.3 to 0.5:5:8 to 10, pouring a mixture into a rectangular mold, and vibrating the interior of the mold by using a vibrating spear with a vibration frequency of 100 to 125 Hz during pouring until the shape of the mixture is flush with each side of the rectangular mold to obtain a green brick;
2) naturally air-drying the green brick in a drying room for 30 to 40 min, taking out the green brick, arranging x×y snail shells with cut-through tails on one side surface of the green brick, wherein x is 5 to 7, y is 3 to 4, and the units of x and y are pieces; drilling once between every two snail shells by using a drill bit to form a through hole; after drilling, placing the green brick in the drying room again; adjusting the temperature to 25 to 40° C., and continuing to dry for 10 to 15 min; finally, taking out the green brick and placing the green brick in a firing kiln, preserving heat at 1400 to 1500° C. for 1.5 to 3 h, firing and molding, taking out the green brick, and demolding to obtain a molded brick;
3) respectively filling the through holes and cavities of the snail shells with silt; continuing to place the green brick in the drying room; adjusting the temperature to 20 to 30° C., drying for 20 to 40 min, and taking out the green brick to obtain the ecological prefabricated brick (2-5), wherein the silt contains herb seeds, the seeding density reaches 10 to 25 kg/mu, and the herb seeds are any species of Festuca arundinacea, bermuda grass, or tifway;
the ecological concrete is a mixture obtained by mixing sandy soil in the river channel, fly ash, and cement in a weight ratio of 10 to 10 to 15:5 to 7:1 to 3; the adhesive is a mixture of one or more of gelatinized raw starch, borax, bentonite, and water-based epoxy resin adhesive; the additive is lime and/or barium carbonate; and the humus is a fermented and decomposed product of sawdust, fruit peels, and straw.