Chemical Engineering or Chemical Technology Process has acquired an over-expanding knowledge base involving transport and reaction as its main contents, that is popular name “3-Tranfer & 1-Reaction”, as the principle of “unit operation” design. In last twenty years we study the acid–alkali united production from metallic salts by hydrolytic action, and found that there be an essential distinction between unit operation and process. One process contains varied many unit operations. Also the essential basic theory for process is closed circular system of multi-phases dynamics. On the basic theory of process guided the ecologic recycle engineering, as the complete base of ecological circular economy at practice or theory.