The disclosure discloses a production method for producing cement and co-producing sulfuric acid from phosphogypsum. The method includes: pretreating and purifying the phosphogypsum to reduce insoluble phosphorus, water-soluble phosphorus impurities, and most free water in the phosphogypsum, directly feeding the materials kneaded and granulated with a reducing agent into a reduction and decomposition integrated rotary kiln with a fluidized preheating function, and controlling to carry out step-by-step heating, drying, dehydration, reduction and decomposition in a gas phase atmosphere under pulverized coal combustion; using sulfur dioxide gas generated after reduction and decomposition to produce the sulfuric acid after dust removal and purification; making the materials after reduction and decomposition enter an oxidation calcining kiln for sintering a cement clinker, and controlling to heat, mineralize and sinter the cement clinker in the gas phase atmosphere under the pulverized coal combustion.

The disclosure discloses a production method for producing cement and co-producing sulfuric acid from phosphogypsum. The method includes: pretreating and purifying the phosphogypsum to reduce insoluble phosphorus, water-soluble phosphorus impurities, and most free water in the phosphogypsum, directly feeding the materials kneaded and granulated with a reducing agent into a reduction and decomposition integrated rotary kiln with a fluidized preheating function, and controlling to carry out step-by-step heating, drying, dehydration, reduction and decomposition in a gas phase atmosphere under pulverized coal combustion; using sulfur dioxide gas generated after reduction and decomposition to produce the sulfuric acid after dust removal and purification; making the materials after reduction and decomposition enter an oxidation calcining kiln for sintering a cement clinker, and controlling to heat, mineralize and sinter the cement clinker in the gas phase atmosphere under the pulverized coal combustion.

Methods and systems for calcining dewatered tailings and/or mine waste are disclosed herein. In some embodiments, the method comprises (i) processing dewatered tailings comprising clay minerals, (ii) calcining the processed tailings to produced calcined tailings, and (iii) altering a composition and/or one or more characteristics of the calcined tailings to produce a cementitious product. Altering the composition can include blending the calcined tailings with one or more additives, such as lime, dolomitic lime, lime kiln dust, argillaceous limestone, limestone, pulverized quicklime, ground calcium carbonate, quicklime, gypsum, natural pozzolans, artificial pozzolans, water, flow aids, or the like.

A method for manufacturing cement may include: supplying at least one etching effluent of a substrate based on silicon including a silicate of an alkali metal, M, having formula SiO.sub.2:M.sub.2O, and having a molar ratio SiO.sub.2/M.sub.2O greater than or equal to 0.8; supplying an aluminosilicate raw material, and mixing the aluminosilicate raw material with the etching effluent having a molar ratio SiO.sub.2/M.sub.2O greater than or equal to 0.8. The silicate solution of alkali metal may be recovered with an existing silicon industrial process, implementing a silicon etching. The environmental impact of the method of manufacturing cement may therefore be reduced.

A wastewater treatment system, including a wastewater phase-separation device, may be used to combine at least one primary treatment chemical and wastewater to produce cleaned water and a sludge byproduct. The wastewater treatment system may also include a wastewater dewatering device that may be used to combine the sludge byproduct and at least one secondary treatment chemical to produce a Medium to High Solids Content Sludge without excess water. A method for producing sludge for cement manufacturing may include combining wastewater and at least one primary treatment chemical to form a liquid phase and a solid phase, where the liquid phase includes clean water and the solid phase includes a sludge byproduct, separating the liquid phase from the solid phase, combining the solid phase with at least one secondary treatment chemical to form an intermediate that contains excess water, and removing the excess water from the intermediate to form a Medium to High Solids Content Sludge.

A wastewater treatment system, including a wastewater phase-separation device, may be used to combine at least one primary treatment chemical and wastewater to produce cleaned water and a sludge byproduct. The wastewater treatment system may also include a wastewater dewatering device that may be used to combine the sludge byproduct and at least one secondary treatment chemical to produce a Medium to High Solids Content Sludge without excess water. A method for producing sludge for cement manufacturing may include combining wastewater and at least one primary treatment chemical to form a liquid phase and a solid phase, where the liquid phase includes clean water and the solid phase includes a sludge byproduct, separating the liquid phase from the solid phase, combining the solid phase with at least one secondary treatment chemical to form an intermediate that contains excess water, and removing the excess water from the intermediate to form a Medium to High Solids Content Sludge.

Methods and systems for calcining dewatered tailings and/or mine waste are disclosed herein. In some embodiments, the method comprises (i) processing dewatered tailings comprising clay minerals, (ii) calcining the processed tailings to produced calcined tailings, and (iii) altering a composition and/or one or more characteristics of the calcined tailings to produce a cementitious product. Altering the composition can include blending the calcined tailings with one or more additives, such as lime, dolomitic lime, lime kiln dust, argillaceous limestone, limestone, pulverized quicklime, ground calcium carbonate, quicklime, gypsum, natural pozzolans, artificial pozzolans, water, flow aids, or the like.

A new construction material prepared from a new pozzolanic material.

Methods of processing biological materials such as the remains of humans or pets, which may be enclosed in a casket, include depositing the biological materials, including the remains and/or the casket, into a cement kiln and operating the cement kiln to produce clinker, thereby incorporating products of the biological remains into the clinker, such as into a crystal or molecular structure of the clinker, and then grinding the clinker to form a cementitious product.

Methods of processing biological materials such as the remains of humans or pets, which may be enclosed in a casket, include depositing the biological materials, including the remains and/or the casket, into a cement kiln and operating the cement kiln to produce clinker, thereby incorporating products of the biological remains into the clinker, such as into a crystal or molecular structure of the clinker, and then grinding the clinker to form a cementitious product.