NOVELTY - Production of fuel ethanol from juice of sweet sorghum stalk comprises extracting juice, adding fermenting yeast, fermenting, distilling, and dehydrating. The fermenting yeast is added during the fermenting process by immobilizing yeast grain. The immobilized yeast grain is obtained by adding fertilized sodium alginate and yeast solution into the juice; stirring to obtain mixed solution; dropping the mixed solution into calcium chloride solution to generate sodium alginate grain after the mixed solution moves at a constant speed; and obtaining the immobilized yeast grain.    USE - Production of fuel ethanol from juice of sweet sorghum stalk (claimed).    ADVANTAGE - The method realizes continuous fermentation, rapid fermenting speed, complete reaction, and high yield; uses advanced device; has no three wastes (waste gas, wastewater, and waste residues); and greatly reduces investment, labor cost, raw material cost, and production cost.    DETAILED DESCRIPTION - Production of fuel ethanol from juice of sweet sorghum stalk comprises extracting juice, adding fermenting yeast, fermenting, distilling, and dehydrating. The fermenting yeast is added during the fermenting process by immobilizing yeast grain. The immobilized yeast grain is obtained by adding fertilized sodium alginate and yeast solution into the juice; stirring to obtain mixed solution; dropping the mixed solution into calcium chloride solution to generate sodium alginate grain after the mixed solution moves at a constant speed; and obtaining the immobilized yeast grain. In the starting period of fermenting, the method comprises delivering fresh air into a reactor; delivering immobilized yeast ion and fermentation liquid into the reactor; stirring the yeast grain and fermentation liquid to roll from top to bottom with compressed air; fermenting to generate a large amount of ethanol and carbon dioxide; releasing heat; cooling the mash in carbon dioxide gas; gas-liquid separating; introducing the mash into a mash storing tank; introducing the gas into the compressor; delivering into the reactor; and continuously recycling by taking carbon dioxide gas other than air as air power of fermentation reaction to form good fermentation fluid. An INDEPENDENT CLAIM is included for a device for producing fuel ethanol from juice of sweet sorghum stalk comprising juicer, juice storing device, immobilized yeast fluid fermenting and mashing device, double-tower distilling device, and molecular sieving dehydrating system. The immobilizing yeast fluid fermenting and mashing device comprises fermentation liquid storage, generator, and mash storing box. The fermenting juice storage is provided with fermenting juice input pipe and communicates with the generator by a first mash pump and a first mash delivery pipe. The upper part of the generator is provided with mature mash overflowing opening communicating with the mash storing box by a mature mash output pipe. The fermenting juice storage communicates with a fixing yeast grainer by a second mash pump and a second mash delivery pipe. The fixing yeast grainer communicates with the generator by a yeast grain delivery pipe.