Abstract: Techniques are generally described for producing cement clinker that includes forming cement clinker in a kiln, heating waste additives, and applying the heated waste additives to the cement clinker in the kiln. Additionally, examples are generally described that include an apparatus for producing cement clinker that includes a kiln in which cement clinker is formed and a device having an opening positioned inside the kiln which provides heated waste additives to the kiln for application to the cement clinker. An example device for applying waste additives to cement clinker includes an eductor configured to receive waste additives and transport air in which the waste additives are pneumatically entrained, and includes a lance coupled to the eductor and configured to receive the pneumatically entrained waste additives and receive a support gas that reacts with the waste additives and heats the same for application to the cement clinker.

Abstract: A synthetic slag is produced by melting the mineral content of an organic carbon-containing mineral, for example, oil shale or tar sands, with a source of lime such as cement kiln dust. The organic carbon, especially hydrocarbon, content of the mineral is oxidized by oxygen gas, which typically is derived from air or an air/oxygen combination, in an exothermic reaction and the heat generated provides the thermal energy for the reaction between the mineral content and the source of lime. In this way the gaseous products will typically comprise nitrogen, unreacted oxygen, water vapor and carbon dioxide, and heat energy can be readily recovered from the hot off gas products evolving during the combustion reaction. The synthetic slag may be pelletized and employed as lightweight mineral aggregate or milled, or atomized and then milled, to cement fineness to provide slag cement.

Abstract: A synthetic slag is produced by a high temperature combustion reaction between coal ash having a high carbon content, and a source of lime such as cement kiln dust. The carbon content of the coal ash is oxidized by oxygen gas, which typically is derived from air or an air/oxygen combination in an exothermic reaction and the heat generated is exploited in the melting process. In this way the gaseous products will typically comprise nitrogen, unreacted oxygen and carbon dioxide, and heat energy can be readily recovered from the hot off gas products evolving during the combustion reaction. The synthetic slag may be pelletized and employed as lightweight mineral aggregate or milled to cement fineness to provide slag cement.

Abstract: A synthetic slag is produced by melting the mineral content of an organic carbon-containing mineral, for example, oil shale or tar sands, with a source of lime such as cement kiln dust. The organic carbon, especially hydrocarbon, content of the mineral is oxidized by oxygen gas, which typically is derived from air or an air/oxygen combination, in an exothermic reaction and the heat generated provides the thermal energy for the reaction between the mineral content and the source of lime. In this way the gaseous products will typically comprise nitrogen, unreacted oxygen, water vapor and carbon dioxide, and heat energy can be readily recovered from the hot off gas products evolving during the combustion reaction. The synthetic slag may be pelletized and employed as lightweight mineral aggregate or milled, or atomized and then milled, to cement fineness to provide slag cement.

Abstract: A synthetic slag is produced by a high temperature combustion reaction between coal ash having a high carbon content, and a source of lime such as cement kiln dust. The carbon content of the coal ash is oxidized by oxygen gas, which typically is derived from air or an air/oxygen combination in an exothermic reaction and the heat generated is exploited in the melting process. In this way the gaseous products will typically comprise nitrogen, unreacted oxygen and carbon dioxide, and heat energy can be readily recovered from the hot off gas products evolving during the combustion reaction. The synthetic slag may be pelletized and employed as lightweight mineral aggregate or milled to cement fineness to provide slag cement.