NOVELTY - Tung oil, where the tung oil is fatty acid and triglyceride mixture and reacted with methanol or ethanol to generate fatty triglyceride which is biodiesel; the heat productivity of the biodiesel is 89% of that of chemical diesel; 20% of biodiesel is mixed in the chemical diesel; the particulate drainage can be reduced by 12%; nitrogen oxide drainage is reduced by 12%; and hydrocarbon drainage is reduced by 20%.    USE - The tung oil is useful for producing biodiesel.    DETAILED DESCRIPTION - Tung oil, where the tung oil is fatty acid and triglyceride mixture and reacted with methanol or ethanol to generate fatty triglyceride which is biodiesel; the heat productivity of the biodiesel is 89% of that of chemical diesel; 20% of biodiesel is mixed in the chemical diesel; the particulate drainage can be reduced by 12%; nitrogen oxide drainage is reduced by 12%; hydrocarbon drainage is reduced by 20%; there is nearly no vulcanized drainage; the tung oil and the methanol or the ethanol are reacted to generate the biodiesel; then the biodiesel is mixed and blended with the chemical diesel so as to generate the biodiesel which is better than the chemical diesel; the biodiesel obtained by reacting the tung oil with the methanol or the ethanol and the chemical diesel are placed at the same time to the same oil pool; an oil-immersed pump, which is a common oil-immersed pump, in the oil pool is started to enable the two oils in the whole oil pool to flow rapidly so as to blend uniformly; a 10 KV oil-immersed pump is used to operate 5 hours below one thousand cube of the oil pool; the quality should be tested; if the quality is satisfied, the product can be sold out; spiral oil presses with high working efficiency are commonly used in the modern oil pressing mills; however, the defect of the spiral oil press is that 5% residual oil cannot be pressed out; the modern edible oil pressing mill with annual output of 100000 ton can be regarded as a large mill; the tung oil can be used as power oil; an oil pressing mill with annual output of 100000 ton in the future will be regarded as a small company; 5% does not sound like much; hot water at 100 degrees C is sprayed to the oil residue from the first oil press; through a spiral transportation groove, the oil residue sprayed with water 30% of the oil residue in weight is input to the second oil press; oil and water are pressed together; because oil is lighter than water, oil is easier to separate; thus, much more oil can be yielded.