Abstract:
A method and system (10) for producing modified coal combustion products are disclosed. The additives reduce the particle sizes of the coal combustion product and may also reduce the un-burned carbon content of the coal combustion product, making the modified product useful as an addition to cementitious materials.
Abstract:
The present invention provides combustion products of hydrocarbon fuels and controlled amounts of metal oxide strength enhancing materials. The combustion products are useful as additives to cementitious materials. A hydrocarbon fuel such as coal is introduced into a combustion chamber (12) and selected amounts of materials comprising CaO, SiO 2 and Al 2 O 3 are also introduced into and/or downstream from the chamber (12). The hydrocarbon fuel undergoes combustion while the metal oxide strength enhancing materials react with each other and/or the ash or other reaction products of the hydrocarbon fuel. The combustion products have been found to significantly increase compressive strengths of cements such as Portland cement. A reduction in SO 2 emission levels also results from the introduction of the metal oxide strength enhancing materials into the combustion process.
Abstract:
Clay and slag additions are made during coal combustion processes to reduce unwanted emissions such as SO 2 , NO x and mercury. The clay additives may include kaolin. The slag additives may include stainless steel slag. The resultant combustion products may be used as cement additives.
Abstract:
A method of combusting coal in the presence of a clay additive and a slag additive is disclosed. The combustion may occur in a coal combustion burner of a coal-fired electrical power generation plant. Co-injections of clay and slag improve operational efficiency of coal fired boilers by improving combustion, thermal heat transfer, steam output and/or electrical power output. The co-injections of clay and slag may also reduce unwanted emissions. The combustion product may be used as a pozzolanic addition to cement.
Abstract:
A method and system (10) for producing modified coal combustion products are disclosed. The additives reduce the particle sizes of the coal combustion product and may also reduce the un-burned carbon content of the coal combustion product, making the modified product useful as an addition to cementitious materials.
Abstract:
The present invention provides combustion products of hydrocarbon fuels and controlled amounts of metal oxide strength enhancing materials. The combustion products are useful as additives to cementitious materials. A hydrocarbon fuel such as coal is introduced into a combustion chamber (12) and selected amounts of materials comprising CaO, SiO 2 and Al 2 O 3 are also introduced into and/or downstream from the chamber (12). The hydrocarbon fuel undergoes combustion while the metal oxide strength enhancing materials react with each other and/or the ash or other reaction products of the hydrocarbon fuel. The combustion products have been found to significantly increase compressive strengths of cements such as Portland cement. A reduction in SO 2 emission levels also results from the introduction of the metal oxide strength enhancing materials into the combustion process.