A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.

A method for releasing impurities from a calcium-based mineral is described. The method comprises reacting a calcium-based mineral containing impurities with an aqueous solution of one or more ionic salts at a temperature of approximately 85° C. or above, wherein at least one of the calcium-based mineral and the one or more ionic salts comprises sulphate and at least one of the calcium-based mineral and the one or more ionic salts comprises ammonium, and wherein the concentration of the solution is approximately 25% or higher mass fraction, such that double salt crystals are formed and impurities are released. The method further comprises separating the double salt crystals from the impurities. Various products of the process are also described.

A method for releasing impurities from a calcium-based mineral is described. The method comprises reacting a calcium-based mineral containing impurities with an aqueous solution of one or more ionic salts at a temperature of approximately 85° C. or above, wherein at least one of the calcium-based mineral and the one or more ionic salts comprises sulphate and at least one of the calcium-based mineral and the one or more ionic salts comprises ammonium, and wherein the concentration of the solution is approximately 25% or higher mass fraction, such that double salt crystals are formed and impurities are released. The method further comprises separating the double salt crystals from the impurities. Various products of the process are also described.

The present disclosure relates to processes and apparatus for calcination of particulate feedstock using process waste gas. In at least one embodiment, a process includes heat treating a particulate carbon feedstock in a heating system to form an activated carbon. The process includes removing a waste gas from the heating system. The process includes introducing the waste gas with a particulate material in a thermal oxidizer coupled with the heating system to form a calcined material. In at least one embodiment, a process includes heat treating a particulate carbon feedstock in a heating system to form an activated carbon. The process includes separating a waste gas from the heating system. The process includes introducing the waste gas with a particulate material in a duct coupled with a thermal oxidizer.

A method for energy generation includes receiving, at a carbon negative energy generation system, input including calcium oxide and water and reacting, within a reaction chamber of the carbon negative energy generation system, the calcium oxide and water to release energy and generate calcium hydroxide. The method further includes directing, by the carbon negative energy generation system, the released energy to facilitate propulsion or onboard electricity generation and dispensing, by the carbon negative energy generation system, the calcium hydroxide into the ocean to sequester atmospheric CO.sub.2.

A composition of milk of lime comprising particles of slaked lime suspended in an aqueous phase, characterised in that said particles of slaked lime have a particle size described by a particle size distribution profile that is narrow and monomodal and the method of production thereof.

A composition of milk of lime comprising particles of slaked lime suspended in an aqueous phase, characterised in that said particles of slaked lime have a particle size described by a particle size distribution profile that is narrow and monomodal and the method of production thereof.

The invention relates to an apparatus and methods for producing liquid colloids such as suspensions of nanoparticles, in which liquid feedstock materials are reacted on a reaction surface of a rotatable plate. The apparatus has a first plate (101) mounted for rotation about a rotation axis (102), the first plate (101) providing a reaction surface (103) having a concave portion; first (106) and second (107) inlet lines arranged to introduce respective first and second liquid feedstock materials to the reaction surface (103); and a collection unit (110) arranged to collect a reaction product formed from reaction of the liquid feedstock materials as a liquid colloid ejected from an outer edge of the plate (101).

The invention relates to an apparatus and methods for producing liquid colloids such as suspensions of nanoparticles, in which liquid feedstock materials are reacted on a reaction surface of a rotatable plate. The apparatus has a first plate (101) mounted for rotation about a rotation axis (102), the first plate (101) providing a reaction surface (103) having a concave portion; first (106) and second (107) inlet lines arranged to introduce respective first and second liquid feedstock materials to the reaction surface (103); and a collection unit (110) arranged to collect a reaction product formed from reaction of the liquid feedstock materials as a liquid colloid ejected from an outer edge of the plate (101).

An aqueous suspension including 5 to 65 wt. % of calcium hydroxide, wherein at least 50 wt. % of the calcium hydroxide is present in the form of nanoparticles, and at least one compound for stabilizing the suspension. The aqueous suspension accelerates the setting of mineral binder compositions without adversely affecting the processing properties of the composition.