# US 11,440,824 B2 · Apparatus for inhibiting formation of calcium based crystal and apparatus for water treatment using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,440,824 B2 - Document ID: US11440824B2 - Status: Granted - Kind: B2 - Application number: 17/022,093 - Filed: 2020-09-16 - Published: 2021-09-30 - Granted: 2022-09-13 - Earliest claimed: 2020-03-26 - Assignees: Korea Institute of Science and Technology - Applicants: Korea Institute of Science and Technology - Inventors: Hye-won Kim; Seong Pil Jeong; Seockheon Lee - Web page: https://patentgrep.com/patent/US11440824B2 ## CPC - C02F 5/083: {Mineral agents} - B01D 61/08: Apparatus therefor - C02F 1/008: {Control or steering systems not provided for elsewhere in subclass C02F} - C02F 1/441: {by reverse osmosis} - C02F 1/447: {by membrane distillation (distillation and evaporation without the use of membranes C02F1/04)} - C02F 2103/06: Contaminated groundwater or leachate - C02F 2103/08: Seawater, e.g. for desalination - C02F 2209/001: Upstream control, i.e. monitoring for predictive control - C02F 2209/055: Hardness - C02F 2303/22: Eliminating or preventing deposits, scale removal, scale prevention (C02F1/042, C02F1/4602, C02F5/00 take precedence) - 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) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract An apparatus for inhibiting formation of calcium based crystal, in which formation of calcium based crystals is inhibited by adding an optimal amount of magnesium to raw water having a high concentration of calcium ions and a high variation in calcium ion concentration and an apparatus for water treatment using the same. ## Claims ### Claim 1 An apparatus for water treatment to inhibit formation of calcium based crystal, comprising: a raw water tank operatively connected to a pretreatment tank to store seawater or wastewater containing a high concentration of calcium ions (Ca2+) as raw water and to supply the raw water to the pretreatment tank; a magnesium supplying device operatively connected to the pretreatment tank to supply magnesium to the pretreatment tank, wherein the magnesium induces a reaction for inhibiting formation of calcium based crystals in the raw water; and a calcium concentration measuring device that measures a concentration of calcium included in the raw water. ### Claim 2 (depends on 1) The apparatus according to claim 1, further comprising a controller to adjust a [Mg2+]/[Ca2+] mole ratio of the raw water in the pretreatment tank to 6-10, wherein Ca2+, Mg2+, CO32−, SO42−in the raw water are kept in an ion state to inhibit formation of calcium based crystals. ### Claim 3 (depends on 1) The apparatus according to claim 1, further comprising: a control device, wherein the control device stores an optimal [Mg2+]/[Ca2+] mole ratio value, calculates an amount of magnesium to be added to the pretreatment tank using the optimal mole ratio value and the concentration of calcium in the raw water measured by the calcium concentration measuring device, and controls an amount of magnesium supplied by the magnesium supplying device based on the calculated amount of magnesium. ### Claim 4 (depends on 1) The apparatus according to claim 1, wherein the magnesium supplying device supplies MgCl2·6H2O. ### Claim 5 (depends on 1) The apparatus according to claim 1, wherein the raw water tank stores seawater. ### Claim 6 (depends on 1) The apparatus according to claim 1, wherein the raw water tank stores wastewater. ### Claim 7 An apparatus for water treatment to inhibit formation of calcium based crystal, comprising: a raw water tank operatively connected to a pretreatment tank to store seawater or wastewater containing a high concentration of calcium ions (Ca2+) as raw water and to supply the raw water to the pretreatment tank; a magnesium supplying device operatively connected to the pretreatment tank to supply magnesium to the pretreatment tank, wherein the magnesium induces a reaction for inhibiting formation of calcium based crystals in the raw water; a membrane device operatively connected to the pretreatment tank to produce treated water after the calcium based crystals in the raw water are inhibited from forming; and a calcium concentration measuring device that measures a concentration of calcium included in the raw water. ### Claim 8 (depends on 1) The apparatus according to claim 1, further comprising a reverse osmosis membrane operatively connected to the raw water tank to supply the raw water. ### Claim 9 (depends on 7) The apparatus according to claim 7, wherein the raw water tank stores seawater. ### Claim 10 (depends on 7) The apparatus according to claim 7, further comprising a reverse osmosis membrane operatively connected to the raw water tank to supply the raw water. ### Claim 11 (depends on 7) The apparatus according to claim 7, further comprising a controller to adjust a [Mg2+]/[Ca2+] mole ratio of the raw water in the pretreatment tank to 6-10, wherein Ca2+, Mg2+, CO32−, SO42−in the raw water are kept in an ion state to inhibit formation of calcium based crystals. ### Claim 12 (depends on 7) The apparatus according to claim 7, further comprising: a control device, wherein the control device stores an optimal [Mg2+]/[Ca2+] mole ratio value, calculates an amount of magnesium to be added to the pretreatment tank using the optimal mole ratio value and the concentration of calcium in the raw water measured by the calcium concentration measuring device, and controls an amount of magnesium supplied by the magnesium supplying device based on the calculated amount of magnesium. ### Claim 13 (depends on 7) The apparatus according to claim 7, wherein the magnesium supplying device supplies MgCl2·6H2O. ### Claim 14 (depends on 7) The apparatus according to claim 7, wherein the membrane device separates concentrated water using a membrane. ### Claim 15 (depends on 7) The apparatus according to claim 7, wherein the membrane device is a membrane device using a reverse osmosis membrane or a membrane device with a membrane distillation membrane. ### Claim 16 (depends on 7) The apparatus according to claim 7, wherein the raw water tank stores wastewater.