Serving in ChinaSteel Corp. in Kaohsiung, Republic of China, since 1975, Chang Shi-Long retiredin the early 2017. Chang’s scope of work included two parts, i.e. energyplanning & management and environment protection management in China SteelCorp. In regard to the promotion of circular economy, Chang has made a huge effortto convince the Chairman of China Steel Corp. to support a corporation proposalbetween LCY (李長榮) Chemical Corporation and China Steel Corp.in 1993. After the approval from the top management, all the engineering andconstruction works were completed in 3 months with a huge energy-saving gain forboth parties as well as intangible environmental benefits one year later. It wasa successful case that inspired most of the other corporations in the sameindustrial park to join the energy system integration together with China SteelCorp. As of 2019, a total of 14 partners have been collaborating with China Steelin satisfaction.