The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The present invention relates to the use of particulate mineral material comprising barite for scavenging heavy metal anions from a liquid medium, wherein the heavy metal anions form water-insoluble barium salts with barium cations of the barite, and wherein the particulate mineral material has a specific surface area of from 0.1 m.sup.2/g to 100 m.sup.2/g, measured using nitrogen sorption and the BET method.

The present invention relates to the use of particulate mineral material comprising barite for scavenging heavy metal anions from a liquid medium, wherein the heavy metal anions form water-insoluble barium salts with barium cations of the barite, and wherein the particulate mineral material has a specific surface area of from 0.1 m.sup.2/g to 100 m.sup.2/g, measured using nitrogen sorption and the BET method.

A method of utilizing contaminated water for soil stabilization operations or for the preparation of aggregates for use in asphaltic mix designs. A method where soil is evaluated for a soil typed and characteristic and a classified mixture of contaminated water is selected based on the soil type and characteristics. A reagent is selected based on the soil type and characteristics and the selected water mixture. The reagent and water mixture are then mixed to form a modified calcium hydroxide that is then applied to the soil.

A method where an aggregated is desired to have better adherent qualities within the mix design for better performance is selected and the surface water reduced/removed through the use of a select reagent and contaminated water.

A method of utilizing contaminated water for soil stabilization operations or for the preparation of aggregates for use in asphaltic mix designs. A method where soil is evaluated for a soil typed and characteristic and a classified mixture of contaminated water is selected based on the soil type and characteristics. A reagent is selected based on the soil type and characteristics and the selected water mixture. The reagent and water mixture are then mixed to form a modified calcium hydroxide that is then applied to the soil.

A method where an aggregated is desired to have better adherent qualities within the mix design for better performance is selected and the surface water reduced/removed through the use of a select reagent and contaminated water.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.

The invention provides methods and compositions for treating wash water from concrete production with carbon dioxide. The treated wash water can be reused as mix water in fresh batches of concrete.