A method of treating an acid effluent including phosphoric acid in accordance with various embodiments may include: providing an acid effluent including phosphoric acid; adding a base and silicon particles from a further effluent to the acid effluent including phosphoric acid so that a mixture is obtained and a solid content is formed; separating from the mixture a solid content including silicon and a salt resulting from a reaction of the base with the acid, so that a clarified effluent can be rejected in the environment and a filter press cake can be obtained and further used as additive for concrete.

A method of treating an acid effluent including phosphoric acid in accordance with various embodiments may include: providing an acid effluent including phosphoric acid; adding a base and silicon particles from a further effluent to the acid effluent including phosphoric acid so that a mixture is obtained and a solid content is formed; separating from the mixture a solid content including silicon and a salt resulting from a reaction of the base with the acid, so that a clarified effluent can be rejected in the environment and a filter press cake can be obtained and further used as additive for concrete.

Brine sludge is an industrial waste generated in chloral alkali industry. The generated brine sludge waste is dumped into landfills and contains barium sulphate, calcium carbonate, magnesium hydroxide, sodium chloride, clay, and toxic elements like chromium, zinc, copper, and vanadium, therefore posing an environmental threat. Consequently, there is an urgent need to convert toxic brine sludge waste into its non-toxic form. The present invention thus aims to achieve total utilization of this brine sludge for making functionalized brine sludge material useful for a broad application spectrum.

Brine sludge is an industrial waste generated in chloral alkali industry. The generated brine sludge waste is dumped into landfills and contains barium sulphate, calcium carbonate, magnesium hydroxide, sodium chloride, clay, and toxic elements like chromium, zinc, copper, and vanadium, therefore posing an environmental threat. Consequently, there is an urgent need to convert toxic brine sludge waste into its non-toxic form. The present invention thus aims to achieve total utilization of this brine sludge for making functionalized brine sludge material useful for a broad application spectrum.

A method of treating an acid effluent including phosphoric acid in accordance with various embodiments may include: providing an acid effluent including phosphoric acid; adding a base and silicon particles from a further effluent to the acid effluent including phosphoric acid so that a mixture is obtained and a solid content is formed; separating from the mixture a solid content including silicon and a salt resulting from a reaction of the base with the acid, so that a clarified effluent can be rejected in the environment and a filter press cake can be obtained and further used as additive for concrete.

A method of treating an acid effluent including phosphoric acid in accordance with various embodiments may include: providing an acid effluent including phosphoric acid; adding a base and silicon particles from a further effluent to the acid effluent including phosphoric acid so that a mixture is obtained and a solid content is formed; separating from the mixture a solid content including silicon and a salt resulting from a reaction of the base with the acid, so that a clarified effluent can be rejected in the environment and a filter press cake can be obtained and further used as additive for concrete.

Brine sludge is an industrial waste generated in chloral alkali industry. The generated brine sludge waste is dumped into landfills and contains barium sulphate, calcium carbonate, magnesium hydroxide, sodium chloride, clay, and toxic elements like chromium, zinc, copper, and vanadium, therefore posing an environmental threat. Consequently, there is an urgent need to convert toxic brine sludge waste into its non-toxic form. The present invention thus aims to achieve total utilization of this brine sludge for making functionalized brine sludge material useful for a broad application spectrum.

Brine sludge is an industrial waste generated in chloral alkali industry. The generated brine sludge waste is dumped into landfills and contains barium sulphate, calcium carbonate, magnesium hydroxide, sodium chloride, clay, and toxic elements like chromium, zinc, copper, and vanadium, therefore posing an environmental threat. Consequently, there is an urgent need to convert toxic brine sludge waste into its non-toxic form. The present invention thus aims to achieve total utilization of this brine sludge for making functionalized brine sludge material useful for a broad application spectrum.

Disclosed is a method for backfilling and reconstructing a carbon storage space in an abandoned main roadway and storing CO.sub.2. A surrounding rock of the main roadway is surveyed through geophysical exploration technology, and an anchor bolts (anchor cables) are used to reinforce and support an area which has unstable confining pressure bearing. According to a width and a height of the roadway section of the main roadway, a support formwork is forged in advance, and after the support formwork is placed in the main roadway, backfilling slurry is injected to the periphery of the support formwork. Meanwhile, supercritical carbon dioxide is injected into the backfilling slurry and the roadway, respectively.

A method for preparing lightweight clay-based aggregates, the aggregates being suitable for use notably in civil engineering works, in particular road uses, and construction. The method for preparing lightweight aggregates includes at least the following steps: a) a step of granulating a clay-based mixture, so as to obtain aggregates, b) a step of drying the aggregates obtained, so as to obtain dried aggregates, c) a step of heat treatment of the dried aggregates, this step having two successive substeps: i) a first substep of heat treatment carried out under a reducing atmosphere at a temperature Ti of between 900 C. and 1200 C. approximately, ii) a second substep of heat treatment carried out under an oxidizing atmosphere at a temperature T2 of between 1050 C. and 1300 C. approximately, and d) a step of cooling the aggregates.