A method for producing a dust-reducing and dust-absorbing material from a nonmetallic mineral and a raw material from a cement plant. The method includes calcining the limestone block, to obtain quicklime; cooling the quicklime at ambient temperature, drying and pulverizing the quicklime, to obtain a first powder essentially consisting of a quicklime powder and a calcium carbonate powder; fully drying and grinding a nonmetallic mineral, to obtain a nonmetallic mineral powder; mixing the first powder and the nonmetallic mineral powder, stirring to be uniform, to obtain a mixture, and ball milling the mixture, to obtain a nano-powder; adding a dust-absorbing material to the nano-powder, adding water and mixing, and pouring the resulting mixture into a mold, and stoving; and air drying the resulting mixture, to obtain a cavernous dust-reducing and dust-absorbing material.

A method for producing a dust-reducing and dust-absorbing material from a nonmetallic mineral and a raw material from a cement plant. The method includes calcining the limestone block, to obtain quicklime; cooling the quicklime at ambient temperature, drying and pulverizing the quicklime, to obtain a first powder essentially consisting of a quicklime powder and a calcium carbonate powder; fully drying and grinding a nonmetallic mineral, to obtain a nonmetallic mineral powder; mixing the first powder and the nonmetallic mineral powder, stirring to be uniform, to obtain a mixture, and ball milling the mixture, to obtain a nano-powder; adding a dust-absorbing material to the nano-powder, adding water and mixing, and pouring the resulting mixture into a mold, and stoving; and air drying the resulting mixture, to obtain a cavernous dust-reducing and dust-absorbing material.

A method for the thermal treatment of mineral raw materials such as limestone or dolomite is shown and described, which includes at least the following steps of a. providing a mineral bulk material and a conductive material and b. placing the mineral bulk material and the conductive material into a kiln, generating an electromagnetic field inside the kiln, thermally treating the mineral bulk material in the kiln by means of electromagnetic excitation of the conductive material in the electromagnetic field, and removing the thermally treated mineral bulk material and the conductive material from the kiln. Using the method described, even large quantities of mineral bulk material can be efficiently converted.

An improved lime mud recycling system including a camera proximate the kiln outlet imaging the granular lime and providing outlet images of the granular lime exiting the kiln, a processor analyzing the outlet images of the granular lime and providing pebble size distributions for the granular lime exiting the kiln, as well as a controller communicating with the processor comparing the pebble size distribution of the granular lime exiting the kiln with predetermined prescribed operating parameters for pebble size distributions for the granular lime exiting the kiln and issuing (I) a notification and/or (II) a control signal prompting remedial action when the pebble size distributions for the granular lime exiting the kiln are outside of the predetermined prescribed operating parameters.

Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

Aspects of the invention include a method of producing a cement material comprising step of: first reacting a calcium-bearing starting material with a first acid to produce an aqueous first calcium salt; second reacting the aqueous first calcium salt with a second acid to produce a solid second calcium salt; wherein the second acid is different from the first acid and the second calcium salt is different from the first calcium salt; and thermally treating the second calcium salt to produce a first cement material. Preferably, but not necessarily, during the second reacting step, reaction between the first calcium salt and the second acid regenerates the first acid.

In an aspect, provided herein are methods for producing sulfuric acid and hydrogen gas, the methods comprising steps of: providing sulfur dioxide formed by thermal conversion of a sulfur-containing species; electrochemically oxidizing said sulfur dioxide to sulfuric acid in the presence of water; and electrochemically forming hydrogen gas via a reduction reaction. In some embodiments, the methods comprise a step of thermally converting said sulfur-containing species to said sulfur dioxide. Systems configured to perform these methods are also disclosed herein. Also provided herein are methods and systems for producing sulfuric acid and hydrogen gas by electrochemically forming the sulfuric acid and the hydrogen gas in a mixture comprising a sulfur material, a supporting acid, and water. Also provided herein are methods and systems for producing a cement material.

In an aspect, provided herein are methods for producing sulfuric acid and hydrogen gas, the methods comprising steps of: providing sulfur dioxide formed by thermal conversion of a sulfur-containing species; electrochemically oxidizing said sulfur dioxide to sulfuric acid in the presence of water; and electrochemically forming hydrogen gas via a reduction reaction. In some embodiments, the methods comprise a step of thermally converting said sulfur-containing species to said sulfur dioxide. Systems configured to perform these methods are also disclosed herein. Also provided herein are methods and systems for producing sulfuric acid and hydrogen gas by electrochemically forming the sulfuric acid and the hydrogen gas in a mixture comprising a sulfur material, a supporting acid, and water. Also provided herein are methods and systems for producing a cement material.

Systems and methods for impurity removal to limestone using modifications to the typical calcination process of turning calcium carbonate into calcium oxide prior to slaking to produce calcium hydroxide. Specifically, substantially increasing the temperature to 1100° C. or higher and increasing soak time can result in reductions in certain undesirable impurities, particularly with regards to lead and lead compounds.

Systems and methods for impurity removal to limestone using modifications to the typical calcination process of turning calcium carbonate into calcium oxide prior to slaking to produce calcium hydroxide. Specifically, substantially increasing the temperature to 1100° C. or higher and increasing soak time can result in reductions in certain undesirable impurities, particularly with regards to lead and lead compounds.