Methods of preparing engineered cementitious composite precursors include carbonating a fly ash comprising >about 25% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the fly ash to a first gas stream comprising carbon dioxide to form a carbonated fly ash. A steel slag is also carbonated that comprises>about 40% by weight of calcium oxide (CaO) and having a water content of >about 12% to <about 18% by weight of water by exposing the steel slag to a second gas stream comprising carbon dioxide to form a carbonated steel slag. The carbonated fly ash and the carbonated steel slag are suitable for use as engineered cementitious composite precursors in a bendable engineered cementitious composite composition that further comprises Portland cement, a polymeric fiber, and a superplasticizer.

The present application pertains to methods for making alkali hydroxide, or alkali carbonates, or alkali bicarbonates, or alkaline-earth sulfates. In one embodiment, a material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with an alkali sulfate to form an alkaline earth sulfate and alkali sulfite or bisulfite. The alkali sulfite or bisulfite is converted into an alkali hydroxide, or an alkali carbonate, or an alkali bicarbonate. In another embodiment, ammonium carbonate or ammonium bicarbonate is reacted with an alkali sulfate, to form ammonium sulfate and an alkali carbonate or alkali bicarbonate. A material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with the ammonium sulfate to form an alkaline earth sulfate and ammonium sulfite or ammonium bisulfite. The ammonium sulfite or bisulfite is regenerated into ammonia, or ammonium hydroxide, or ammonium carbonate, or ammonium bicarbonate.

A method is provided for inputting thermal energy into fluidic medium in a process or processes related to oil refining and/or petrochemical industries by at least one rotary apparatus comprising a casing with at least one inlet and at least one exit, a rotor comprising at least one row of rotor blades arranged over a circumference of a rotor hub mounted onto a rotor shaft, and a stator configured as an assembly of stationary vanes arranged at least upstream of the at least one row of rotor blades. In the method, an amount of thermal energy is imparted to a stream of fluidic medium directed along a flow path formed inside the casing between the inlet and the exit by virtue of a series of energy transformations occurring when said stream of fluidic medium passes through stationary and rotating components of said rotary apparatus, respectively. The method further comprises: integration of said at least one rotary apparatus into a heat-consuming process facility configured as a refining and/or petrochemical facility and further configured to carry out heat-consuming process or processes related to refining of oil and/or producing petrochemicals at temperatures essentially equal to or exceeding 500 degrees Celsius (° C.), and conducting an amount of input energy into the at least one rotary apparatus integrated into the heat-consuming process facility, the input energy comprises electrical energy. A rotary apparatus and related uses are further provided.

Embodiments described herein relate to capturing and sequestering CO.sub.2 emissions from the cement production process with the potential to produce carbon-negative cement. Methods described herein can include contacting calcium oxide (CaO) with ambient air at a carbonation station to form a first stream of calcium carbonate, combining the first stream of calcium carbonate with a second stream of calcium carbonate in a calciner to form a combined stream of calcium carbonate, and applying heat to the calciner to decompose the combined stream of calcium carbonate into a stream of calcium oxide and a CO.sub.2 stream. The method further includes sequestering the CO.sub.2 stream, dividing the stream of calcium oxide into a first calcium oxide stream and a second calcium oxide stream, feeding the first stream of calcium oxide to the carbonation station, and feeding the second stream of calcium oxide to a kiln to produce a clinker.

A system for making oxide material may comprise a preheating cyclone stage for receiving a solid carbonate material and operating at a temperature less than a calcination temperature of the solid carbonate material, a calcination cyclone stage for heating the preheated solid carbonate material and operating at a temperature of at least the calcination temperature to convert the preheated solid carbonate material to a solid oxide material and carbon dioxide gas, a cooling cyclone stage for cooling the solid oxide material and operating at a temperature less than the calcination temperature to cool the solid oxide material to ambient temperature, a first recirculating system to extract and recirculate a first gas from an outlet of the calcination cyclone stage to an inlet of the calcination cyclone stage zone, and a second recirculating system to extract and recirculate a second gas from the cooling cyclone stage to the preheating cyclone stage.

The present application pertains to methods for making metal oxides and/or citric acid and/or capturing carbon dioxide. In one embodiment, the application pertains to a process for producing calcium oxide, magnesium oxide, or both from a material comprising calcium and magnesium. The process may include reacting a material comprising calcium carbonate and magnesium carbonate. Separating, concentrating, and calcining may lead to the production of oxides such as calcium oxide or magnesium oxide. In other embodiments the application pertains to methods for producing an alkaline-earth oxide and a carboxylic acid from an alkaline earth cation-carboxylic acid anion salt. Such processes may include, for example, reacting an alkaline-earth cation-carboxylic acid anion salt with aqueous sulfur dioxide to produce aqueous alkaline-earth sulfite or bisulfite and an aqueous carboxylic acid solution. Other useful steps may include desorbing, separating, and/or calcining.

The present invention relates to a device for heat-treating solid material, in particular in granular form, wherein the device comprises a kiln and an external heat generator, wherein said kiln comprises at least one sloped sliding surface on which a bed of said solid material slides down within said kiln due to gravity while a hot gas generated by the external heat generator is led through said solid material to heat said solid material to a desired temperature in order to change the substance properties of said solid material. According to the invention, said external heat generator for generating said hot gas is external to said kiln, wherein said kiln further comprises at least one kiln gas inlet through which said hot gas enters said kiln, such that the necessary temperature of said hot gas can be controlled precisely in that said hot gas is generated in said external heat generator, ensuring that the solid material does not experience temperatures above an allowed maximum temperature, and further such that the solid material is not exposed to radiation from a burner.

The present invention relates to a device for heat-treating solid material, in particular in granular form, wherein the device comprises a kiln and an external heat generator, wherein said kiln comprises at least one sloped sliding surface on which a bed of said solid material slides down within said kiln due to gravity while a hot gas generated by the external heat generator is led through said solid material to heat said solid material to a desired temperature in order to change the substance properties of said solid material. According to the invention, said external heat generator for generating said hot gas is external to said kiln, wherein said kiln further comprises at least one kiln gas inlet through which said hot gas enters said kiln, such that the necessary temperature of said hot gas can be controlled precisely in that said hot gas is generated in said external heat generator, ensuring that the solid material does not experience temperatures above an allowed maximum temperature, and further such that the solid material is not exposed to radiation from a burner.

A method for sequestating carbon dioxide from flue gas by using a cement clinker. The products of this method can also be used to prepare microfiber-reinforced cement. The method of the present disclosure is capable of capturing and storing carbon dioxide in flue gas, such as cement kiln flue gas.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.