NOVELTY - Heat exchanging system for producing biological diesel oil comprises e.g. an evaporimeter, heat exchangers (I), (II) and (III), an enzymatic reaction temperature maintaining and a raw material oil melting systems. The industrialized production of biological diesel oil comprises: processing fine methyl ester steam distilled by evaporimeter to obtain a finished fine methyl ester, heating, distilling, exchanging cooling water of heat exchangers (II) and (III) with fine methyl ester, heating and transmitting the fine methyl ester after vacuum dehydration into the heat exchanger (III).    USE - The heat exchanging system is useful for the industrialized production of biological diesel oil.    ADVANTAGE - The system: utilizes the waste heat recovered by the heat exchanger during the production process of the biological diesel oil for heating the material in other sections, thus saving the energy consumption and the production cost; and is economical.    DETAILED DESCRIPTION - Heat exchanging system for producing biological diesel oil comprises an evaporimeter, a heat exchanger (I), a heat exchanger (II), a heat exchanger (III), a dealcoholization workshop section heating system, an enzymatic reaction temperature maintaining system, a raw material oil melting system, a preheating system and a raw material oil vacuum dehydration system. The industrialized production of biological diesel oil comprises: processing the fine methyl ester steam distilled by the evaporimeter having the heat conducting oil by the heat exchanger (I), heat exchanger (II) and heat exchanger (III) for exchanging the heat and to obtain the finished fine methyl ester; heating the fine methyl ester steam heated by the evaporimeter having the heat conducting oil with the crude methyl ester, distilling through the heat exchanger (I), preheating and raising the temperature of the crude methyl ester; exchanging the cooling water of the heat exchanger (II) with the fine methyl ester and heating after the first level cooling and using the produced hot water for heating the dealcoholization workshop system to produce the biological diesel oil; exchanging the cooling water of the heat exchanger (III) with the fine methyl ester and heating after the second level cooling and using the produced hot water for melting the raw material oil in the pre-processing workshop section and preheating; using the hot water after the heat exchanging process for maintaining the enzymatic reaction temperature in the dealcoholization workshop system for producing the biological diesel oil; using the fine methyl ester after the first level cooling in the raw material oil vacuum dehydration system for pre-processing the workshop section oil for the flash evaporation and dehydration on the raw material oil after the centrifuging and decontaminating processes, and transmitting the fine methyl ester after vacuum dehydration into the heat exchanger (III).