Please select the most similar patent number from A, B, C and D. Which number is?
Disclosed is a chemical leaching and separating method for contaminants in soil and solid waste and separation system thereof. The separating method comprises: in a chemical leaching step, first reacting a high-concentration leacheate with the contaminants in the soil or the solid waste, so that the contaminants in the soil or the solid waste dissolve into the leacheate as solutes; and then, in a countercurrent washing step, partially displacing the contaminants as the solutes in the mixed solution obtained after leaching the soil or the solid waste by a washing liquid till the mixed solution obtained after leaching the soil or the solid waste has a contaminant concentration equal to the targeted concentration of the treatment, and may be discharged and satisfy the treatment requirement. A regeneration cycle step is dynamically carried out during the steps of the chemical leaching and the countercurrent washing, so that the volume of the leacheate and the concentration of the contaminants in the leacheate are constant in the whole treatment process of the contaminants in the soil or the solid waste to achieve a stable circulation. The separation system can implement the leaching and separating method.
A: A method for recovering perfluorinated compound from sewage, which comprises the following steps: an electric flocculation step, using an electric flocculation method to adsorb the perfluorinated compound in an aqueous solution or a water-organic solvent mixed solution onto the surface of flocs produced by electric flocculation to form sludge; an elution step, carrying out an organic solvent elution treatment on the above-mentioned sludge containing perfluorinated compound to separate the perfluorinated compound from the sludge and form a concentrated perfluorinated compound solution; and a distillation step, distilling the produced concentrated perfluorinated compound solution to obtain perfluorinated compound solids and a distillate, the distillate being used as an elution liquid of the above-mentioned elution step. Zn(OH) 2  flocs produced in situ by electric flocculation have a very high adsorption capacity and a fast adsorption rate for the perfluorinated compound and can recover high-concentration and low-concentration perfluorinated compounds from sewage and purify the sewage simultaneously. Since the electric flocculation treatment has low costs and low sludge production amount, the large-scale application of the method is economically feasible.
B: A recovering system for a reactive dye dyeing residual liquid, comprising an extraction system and a reverse extraction system. The extraction system extracts a reactive dye in the residual liquid into an organic solvent, and following extraction the residual liquid is used for dyeing, and the reverse extraction system reversely extracts the reactive dye in the organic solvent, with the reactive dye being included therein after the extraction, in the extraction system into an aqueous solution, and the organic solvent after the reverse extraction is recycled to the extraction system as an extractant. Further disclosed is a recovery method. The centrifugal extraction and separation technology used in the present invention is a reversible reaction-based polar organic chemical extraction and separation method, in which a water plus salt system and an extractant system respectively form a closed-loop cycle during the treatment of a dyeing residual liquid, and interact with each other in the centrifugal extraction device to continuously extract the water-soluble dye in the dyeing residual liquid, so that the residual liquid having high salinity can be recycled, and the discharge of a large amount of salt is avoided. The environmental pollution is reduced, and the production cost is reduced.
C: Provided are a combined soil washing desorption method and device. The method is as follows: polluted soil is sprayed and sieved with a wet multistage vibrating sieve (3) to remove large particles of stones or coarse sand that can be directly backfilled; washing desorption treatment is carried out on a fine soil particle suspension, and same is subjected to cyclones (10-1,10-2,10-3) connected in series and respectively equipped with solid-liquid mixers (8-1,8-2) and a micro rotational flow sequencer (9-1) in order to achieve the separation of clay pollutants of small particle size; washing desorption treatment and cyclone separation are carried out on the remaining sandy soil of intermediate particle size, wherein the recycling of a washing liquid is achieved by a precision filter (12-1); and washing treatment using clear water and cyclone separation are carried out on the soil after filtration, and finally, after dehydration through a centrifugal machine (13), the deep separation of waste water and soil particles is finally achieved, thus achieving the purposes of backfilling soil, recycling tap water and recycling a washing agent. The device parameters can be adjusted and optimized according to actual conditions, thereby effectively removing pollutants containing heavy metals, pesticides, etc., and overcoming the deficiency that current soil washing cannot be industrialized.
D: A method for removing organic pollutants based on microporous mineral adsorption and coupling and microwave degradation mainly comprises the steps of: filling a hydrophobic porous mineral adsorbent in adsorption columns (7, 9) to adsorb organic pollutants in organic wastewater; and starting a microwave generator (10) to cause the organic pollutants adsorbed in the adsorption columns (7, 9) to degrade under microwave induction after the adsorbent is saturated. Continuous treatment on the organic wastewater is realized via alternate operation and regeneration of the two adsorption columns (7, 9). The method can be used for pollution control of underground water, surface water and drinking water.
Answer: C