# US 10,245,626 B2 · Mine drainage remediation using barium carbonate dispersed alkaline substrate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,245,626 B2 - Document ID: US10245626B2 - Status: Granted - Kind: B2 - Application number: 15/508,757 - Filed: 2015-09-04 - Published: 2017-09-28 - Granted: 2019-04-02 - Earliest claimed: 2014-09-04 - Assignees: University of the Free State - Applicants: University of the Free State - Inventors: Esta Van Heerden; Julio Hernandez Castillo; Alba Gomez; Rohan Posthumus; Walter George Van Der Hoven - Web page: https://patentgrep.com/patent/US10245626B2 ## CPC - B09C 1/10: microbiologically, {biologically} or by using enzymes - B09C 1/00: Reclamation of contaminated soil - B09C 1/02: Extraction using liquids, e.g. washing, leaching {, flotation} - B09C 1/08: chemically - C02F 1/5245: {using basic salts, e.g. of aluminium and iron} - C02F 1/66: by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) - C02F 3/106: {Carbonaceous materials} - C02F 3/2806: {Anaerobic processes using solid supports for microorganisms} - C02F 3/305: {characterised by the denitrification} - C02F 3/345: {for biological oxidation or reduction of sulfur compounds} - C02F 3/107: {Inorganic materials, e.g. sand, silicates} - C02F 2101/10: Inorganic compounds - C02F 2101/101: {Sulfur compounds} - C02F 2101/103: {Arsenic compounds} - C02F 2101/105: {Phosphorus compounds} - C02F 2101/163: {Nitrates} - C02F 2101/20: Heavy metals or heavy metal compounds - C02F 2101/203: {Iron or iron compound} - C02F 2103/10: from quarries or from mining activities - C02F 2305/06: Nutrients for stimulating the growth of microorganisms - Y02W 10/10: Biological treatment of water, waste water, or sewage - B09C: RECLAMATION OF CONTAMINATED SOIL (gatherers for removing stone or the like from the soil A01B43/00; sterilising soil by steam A01G11/00; removing undesirable matter, e.g. rubbish, from the land E01H15/00) - C02F: TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (separation in general B01D; special arrangements on waterborne vessels of installations for treating water, waste water or sewage, e.g. for producing fresh water, B63J; adding materials to water to prevent corrosion C23F; treating radioactively-contaminated liquids G21F9/04; regeneration of reactants for recirculation into processes, see the relevant places for the processes) - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract The present invention relates to a treatment system having a barium carbonate (BaCO3) dispersed alkaline substrate (BDAS) for use in the remediation or at least partial remediation of mine drainage (MD) and/or environmental media contaminated with a source of MD. The invention utilizes chemical, biological and combined treatment systems remove high concentrations of sulfates, hardness, heavy metals and N-compounds, that may exist in the MD as well as high concentrations of alkalinity produced during the remediation process. The invention further extends to a process for treating MD and/or environmental media contaminated with MD and to an apparatus for use in this process. ## Claims ### Claim 1 A fixed-film bioreactor for bio-remediation, or at least partial bio-remediation, of environmental media contaminated with a source of mine drainage (MD), and wherein the bioreactor is a down-flow reactor with a supernatant open to the atmosphere in order to maximize iron oxidation and to minimize iron (II) mobility in the bioreactor, said fixed-film bioreactor including: (i) a support matrix; (ii) a barium carbonate BaCO3 alkaline substrate for removing sulphate, cation, electrical conductivity (EC) and total dissolved solids (TDS) by precipitation; and (iii) a microbial consortium for removing nitrates and cyanide. ### Claim 2 (depends on 1) The fixed-film bioreactor of claim 1, wherein the fixed-film bioreactor is in the form of a fixed-film biocell. ### Claim 3 (depends on 1) The fixed-film bioreactor of claim 1, wherein the support matrix serves as an inert physical support mechanism for a microbial community. ### Claim 4 (depends on 1) The fixed-film bioreactor of claim 1, wherein the support matrix serves as surface media for the dispersal of the BaCO3 alkaline substrate thereby allowing the formation of a dispersed alkaline substrate (DAS). ### Claim 5 (depends on 4) The fixed-film bioreactor of claim 4, wherein the dispersed alkaline substrate (DAS) is in the form of a BACO3 dispersed alkaline substrate (BDAS). ### Claim 6 (depends on 1) The fixed-film bioreactor of claim 1, wherein the support matrix material comprises a material selected from the group consisting of an inert organic medium, wood chips and gravel. ### Claim 7 (depends on 6) The fixed-film bioreactor of claim 6, wherein the support matrix material comprises wood chips. ### Claim 8 (depends on 6) The fixed-film bioreactor of claim 6, wherein the support matrix material consists of a combination of wood chips and quartz gravel. ### Claim 9 (depends on 7) The fixed-film bioreactor of claim 7, wherein the ratio of wood chips to BACO3 is 4:1 (v/v). ### Claim 10 (depends on 6) The fixed-film bioreactor of claim 6, wherein the support matrix provides an electron donor for the microbial consortium. ### Claim 11 (depends on 6) The fixed-film bioreactor of claim 6, wherein the inert organic material is manure. ### Claim 12 (depends on 11) The fixed-film bioreactor of claim 11, wherein the manure is horse manure. ### Claim 13 (depends on 1) The fixed-film bioreactor of claim 1, wherein the microbial consortium comprises sulfate reducing microorganisms. ### Claim 14 (depends on 1) The fixed-film bioreactor of claim 1, wherein the dissolution of barium carbonate BACO3 has a pH of about pH 3 to about pH 8.5. ### Claim 15 (depends on 1) The fixed-film bioreactor of claim 1, wherein a zero valent iron (ZVI) is included. ### Claim 16 (depends on 1) The fixed-film bioreactor of claim 1, wherein the fixed-film bioreactor operates under aerobic conditions. ### Claim 17 (depends on 1) The fixed-film bioreactor of claim 1, wherein the fixed-film bioreactor operates under anaerobic conditions. ### Claim 18 (depends on 1) The fixed-film bioreactor of claim 1, wherein the bioreactor can operate at either continuous or pulsed flow. ### Claim 19 (depends on 1) The fixed-film bioreactor of claim 1, wherein the precipitation is in the form of any one or more of barium sulfate (BaSO4), carbonates ((Me2+)CO3) and oxy-hydroxides (Me2+/3+O(OH)). ### Claim 20 A process for the bioremediation, or at least partial bioremediation, of environmental media contaminated with MD, wherein the process includes the step of removing environmental media from a mine drainage contaminated site and exposing the environmental media to a mixture including an indigenous microbial consortium of microorganisms from MD, wood chips as a minimal source of electron donor, and a dispersed alkaline substrate including dispersed barium carbonate BaCO3, allowing for the chemically and biologically mediated precipitation of sulfate, nitrate, phosphate and metals. ### Claim 21 (depends on 1) A process for the bioremediation, or at least partial bioremediation, of environmental media contaminated with MD, wherein the process includes the step of removing environmental media from a mine drainage contaminated site and exposing the environmental media to a mixture including an indigenous microbial consortium of microorganisms from MD, wood chips as a minimal source of electron donor, and a dispersed alkaline substrate including dispersed barium carbonate BaCO3, allowing for the chemically and biologically mediated precipitation of sulfate, nitrate, phosphate and metals, and wherein said process includes the following stages: a first stage including the steps of: (i) providing a bioreactor as claimed in claim 1, wherein the bioreactor includes a support matrix which has been wetted and pre-treated with BaCO3 to form a BaCO3 dispersed alkaline substrate; (ii) introducing the MD contaminated media into the bioreactor and subsequently introducing the indigenous microbial consortium of microorganisms; and (iii) controlling the hydraulic retention time of the bioreactor such that the hydraulic retention time is between about 9 hours and about 24 hours; and a second stage including the steps of: (iv) allowing for the precipitation of the sulfate present in the source of the MD contaminated environmental media as barium sulfate (BaSO4); (v) allowing for the precipitation of Ca, Mg, Na and trace metals present in the source of the MD contaminated environmental media as calcite and aragonite (CaCO3); (vi) allowing for the precipitation of heavy metals present in the source of the MD contaminated environmental media as oxy-hydroxides (Me2+/3+O(OH)); and (vii) removing cyanide and nitrates.