Wort kettle is the most energy consumption equipment in brewery, so we especially rebuild the inner heater, wort recycling system and low pressure boiling. Adopt automatic control kettle inside pressure, ensure wort low steam pressure, dynamic and circulating boiling, wort temperature equality. The boiling intensity now decrease to 5-6% from original 8-10%, then set up automatic safe device to exert twice steam energy recovery which can spare the energy and improve the wort quality.