NOVELTY - Extracting pyrethrin from Pyrethrum involves: (a1) low-temperature multi-stage continuous countercurrent extracting, (b1) dissolving and baking, (c1) low temperature negative pressure steaming and separating, (d1) vacuum distilling and condensing, (e1) solvent condensing and recovering, and (f1) paraffin wax tail gas recovering.    USE - For extracting pyrethrin from pyrethrum (claimed).    ADVANTAGE - The method is simple and easy to produce; has zero pollution discharge; and is energy-saving and environment-friendly. The pyrethrum extracting provides a great innovation in production of pyrethrin, which results in economic and social benefit.    DETAILED DESCRIPTION - Extracting pyrethrin from pyrethrum involves: (a1) low-temperature multi-stage continuous countercurrent extracting, (b1) dissolving and baking, (c1) low temperature negative pressure steaming and separating, (d1) vacuum distilling and condensing, (e1) solvent condensing and recovering, and (f1) paraffin wax tail gas recovering. The step (a1) involves sending the pyrethrum with water content of less than or equal to 8% to the countercurrent multi-stage extractor at 40 degrees C, where the pyrethrum contains 1-1.4% of pyrethrin; taking normal hexane as extractant, the adding amount of normal hexane is 6-8 times of pyrethrum; extracting by normal hexane with 0.4% of pyrethrin, drying and extracting with 0.3%, 0.2% and 0.1% of normal hexane solvent, in turn extracting, drying and repeatedly extracting for 80-120 minutes and washing with the normal hexane solvent without containing pyrethrin, drying for 60-80 minutes, and extracting the content of pyrethrin, where the pyrethrin residue is less than 0.5% in the pyrethrum, and the extracting rate of pyrethrin is more than or equal to 90%. The step (b1) involves sending the extracted pyrethrin residue to the multi-layer continuous baking dissolver, where the fourth disk in the dissolver is heating layer, the fifth disk is direct steam adding layer, the sixth disk is hot wind baking layer, the seventh disk is cold wind temperature reducing layer; stirring and heating the pyrethrin, gradually baking, removing the normal hexane solvent, directly accessing the vapor to the material at 100-130 degrees C, extracting the residual normal hexane solvent, sending the material to the hot wind drying layer to remove the water at 80-90 degrees C; sending to the cold wind layer at 25-30 degrees C, reducing the temperature, reducing the temperature of pyrethrin pulp to 50-60 degrees C, and reducing the water to less than 10%, the residue of pyrethrin is less than 0.1%, removing the pyrethrin pulp. The step (c1) involves separating to remove big impurities in the normal hexane solution containing pyrethrin, separating to remove the small impurities by 120-200 mesh of precise filter, sending to a long tube film steamer to remove 70-80% of normal hexane solution, controlling the temperature of the long tube steamer to 55-60 degrees C with -0.05 MPa, sending the organic solvent to a second long tube film steamer to separate and steam, steaming 80-85% of normal hexane solvent, controlling the steaming temperature at 75-85 degrees C under -0.04 MPa, sending the organic solvent to the third film steamer, removing 95% of normal hexane solution, controlling the steaming temperature at 85-95 degrees C under -0.05 MPa, and separating and dissolving 95% of normal hexane. The step (d1) involves vacuum distilling and condensing in the steamed pyrethrin solution, where the content of pyrethrin is 30-40%, first-stage vacuum condensing and controlling the temperature at 90-95 degrees C, controlling the steaming pressure at -0.05 MPa, removing the residual normal hexane solution to obtain the pyrethrin. The step (e1) involves solvent condensation recovery from multi-stage counter-current of the volatile solvent, where the multi-stage converter has volatized normal hexane gas and gas of pyrethrum, cooling the steamed, dissolved and baked, distilled and condensed normal hexane steam in the condenser, the condensed normal hexane contains part of water, putting the normal hexane to the water separation box, separating the normal hexane and water with the theory that the normal hexane and water are insoluble and have big density difference; and draining the wastewater and recycled the normal hexane. The step (f1) involves sending normal hexane gas to the absorbing tower according to the solvable property of normal hexane and paraffin wax, spraying the paraffin wax from upper to lower part, raising the gas from lower to upper part, fully countercurrent contacting in the filler of absorbing tower, absorbing the normal hexane by paraffin wax, draining the uncondensed gas, heating the paraffin wax absorbed with normal hexane to 115-125 degrees C and coming to the stripper tower, separating the paraffin wax solution from the normal hexane, cooling the paraffin wax to 35 degrees C by cooler to recycled use, and putting the normal hexane gas to the condensing system to cool into liquid and recycled.