Demchuk was born in 1949 in Ukraine. In 1968 he graduated from the Omsk special vocational school No. 57 as the “driver of compressor units.” 

Between 1968 and 1976 he worked at the Omsk refinery as the engineer of compressor units of the 5th category. In May 1976, came to the construction of the Pavlodar Oil and Chemistry Refinery (POCR), where he worked for 36 years. He started as a senior engineer of compressor units of the 6th category. In 2000, he was appointed as the head of the gas compressor workshop No. 1 (LK-6U).

“1976 was a significant year in my life and the destinies of many of my colleagues who have tied their destinies with our plant,” Demchuk recollected. 

“The first week of work at the refinery was just mostly studying proper documents, meeting with people visiting companies in Omsk, Perm, Ufa and other cities almost daily. Mostly workers on call arrived these were experts familiar with the processes of refining. There was a lot of work, we worked together and with enthusiasm. Very soon I learned for myself the truth that this refinery – was my refinery. My destiny confirmed this, because personal success and well-being closely depended and depends on the operation of the refinery. All the years spent here were interesting. The refinery has seen its ups and downs. Defeats and victories of the refinery – they are my defeats and victories. The main thing - is we have learned to work without a state of emergency in all modes. Together we have experienced the difficult 90s. Now, our company stands firmly on its feet. Many of the staff do not just work together, their families also have good relations and this further brings all together. I was lucky that all the years I worked in a team of the workshop No. 1: it all began here, these settings bear my sweat and work, my life. I am proud of my team and the refinery.”

Demchuk has been awarded the Order of Labor Glory III degree and the October Revolution and jubilee medals ‘30 years of the refinery’ and ‘75 years of Pavlodar region’.