NOVELTY - Refined biodiesel production involves growing energy grass near a water source. A microalgae culturing, a processing factory and a biodiesel refinery are formed, where the main fuel for an electricity generating and heat supplying device is the energy grass. The electricity generated by the electricity generating and heat supplying device is utilized for culturing microalgae and refining biodiesel. The gases, which are generated by the electricity generating and heat supplying device are purified and the purified gases are supplied to an optical bioreactor as the main source of carbon.    USE - Method for producing refined biodiesel (Claimed).    ADVANTAGE - The refined biodiesel production method enables to reduce production cost, produces biological diesel cleanly and treats polluted waters.    DETAILED DESCRIPTION - The energy grass is grown near water source and a microalgae culturing, a processing factory and a biodiesel refinery are formed, where the main fuel for an electricity generating and heat supplying device is the energy grass The electricity generated by the electricity generating and heat supplying device is utilized for culturing microalgae and refining biodiesel. The gases, which are generated by the electricity generating and heat supplying device are purified and the purified gases are supplied to an optical bioreactor as the main source of carbon. The waste water, which is produced in a leaching tank, leaches the fly ash generated by the electricity generating and heat supplying device. The leached liquid is added to the culture solution tank of the microalgae as nutrient salts. The microalgae slag is transferred into a microalgae complex fertilizer by a tablet machine and the obtained fertilizer is utilized for growing the energy grass. A three stage culturing process is performed in an Erlenmeyer flask, an air lift optical bioreactor and the optical bioreactor to prepare an industrial production strain. The culture solution is added in the reactor so that the liquid level reaches 10 cm and the industrial production strain is inoculated. The culture solution is added gradually till the liquid level reaches 20 cm. The carbon dioxide gas is supplied to the culture solution to ensure efficient growth of the microalgae and the temperature of the culture solution is controlled in the range of 15-35 degrees C. The valve of a liquid draining pipe is opened to drain the microalgae liquid and the microalgae is collected. The microalgae diesel is extracted through the extraction kettle by utilizing a fatty acid methyl ester. The extracted material is separated by a liquid-solid separation process by utilizing a horizontal helical centrifugal machine. The separated microalgae is disposed in a batch mixer to prepare microalgae compound fertilizer and the separated liquid phase is added in a water diesel separator to obtain a diesel phase and a water phase, where the diesel phase is the microalgae diesel. The water phase material is concentrated in a vacuum concentrating kettle at a temperature of 60-70 degrees C. Solid ammonium sulfate is added to the concentrated solution and the mixture is stirred for depositing microalgae protein. The salted material is separated by a liquid-solid separation process by utilizing a high-speed centrifugal filter. The separated solid phase is added to a dryer to prepare microalgae protein. The separated liquid phase is added to an alcohol depositing kettle and a microalgae polysaccharide is extracted by utilizing ethanol depositing method. The material is separated by a liquid-solid separation process by utilizing a high-speed centrifugal filter and the obtained liquid phase is added to ethanol recovery tower to obtain a microalgae liquid fertilizer, which is utilized as the leaf surface fertilizer for planting energy grass. The separated solid phase is dried to obtain microalgae polysaccharide. The microalgae diesel and refining biodiesel are pretreated in a multifunctional reaction kettle. The free fatty acids in raw diesel are esterified into fatty acid methyl ester by performing a pre-esterification reaction by adding methanol and concentrated sulfuric acid. A neutralization reaction is performed by adding sodium hydroxide saturated solution to reaction kettle. The solution is vacuumized and dehydrated for separating methanol, by heating the kettle at constant temperature and the separated methanol is recycled. The mixture of fatty acid methyl ester and the auxiliary product of glycerine is discharged from the kettle. The coarse fatty acid methyl ester is separated through a disperser, washed and distilled to obtain biodiesel. The glycerine is utilized as a carbon source for culturing microalgae. The sodium hydroxide waste water is utilized as a carbon dioxide absorbent.