Abstract: A process for producing calcined coke agglomerates characterized by having a low reactivity to carbon dioxide. The process includes calcining green coal agglomerates at a temperature within the range of 1700.degree. F. to 1950.degree. F. (927.degree. C. to 1066.degree. C.) in a calciner. The agglomerates are exposed to a gaseous atmosphere which before cracking contains not less than 20% by volume of at least one straight chain aliphatic hydrocarbon gas containing one to four carbon atoms. The gaseous atmosphere is preheated to a temperature within the range of 200.degree. F. to 700.degree. F.(93.degree. C. to 371.degree. C.) prior to being introduced into the calciner. Carbon produced when the hydrocarbon gas is cracked, is deposited as vitreous carbon on the surfaces, in the fissures and in the pores of the agglomerates. The calcined coke aggglomerates discharged from the calciner have a reactivity to carbon dioxide of between 2% to 8%.