Method for reducing fresh water dosage during carrageenan extraction by eucheuma

The invention relates to a method for reducing the fresh water use amount when carrageenan is extracted by using eucheuma. According to the production process flow when the carrageenan is extracted by the eucheuma, the water use amount characteristic of each working procedure and the requirement on the production water, after the sea water is subjected to sand filtration, coagulation treatment and pH value adjustment, sea water is used to replace fresh water to perform production in the processes of eucheuma base process and bleaching so as to reduce the use amount of the fresh water. The method has apparent effect on reducing the fresh water use amount. When the powder carrageenan product is produced, the fresh water use amount can be reduced to 42.9 percent. The method has great significance to build a water-saving and environment-friendly society, improve the enterprise economic benefits, and guarantee the sustainable development of the enterprise and the society.