# US 2018/0021691 A1 · Multi-stage distillation system, method for the operation thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0021691 A1 - Document ID: US20180021691A1 - Status: Published application - Kind: A1 - Application number: 15/550,622 - Filed: 2016-02-10 - Published: 2018-01-25 - Earliest claimed: 2015-02-13 - Assignees: Thermal Purification Technologies Limited - Applicants: Thermal Purification Technologies Limited - Inventors: MARKUS LEHMANN - Web page: https://patentgrep.com/patent/US20180021691A1 ## CPC - B01D 1/26: Multiple-effect evaporating - B01D 1/0082: {Regulation; Control} - B01D 5/0036: {Multiple-effect condensation; Fractional condensation} - B01D 5/0051: {Regulation processes; Control systems, e.g. valves} - B01D 5/006: {with evaporation or distillation} - C02F 1/048: {Purification of waste water by evaporation} - C02F 2103/08: Seawater, e.g. for desalination - C02F 2201/009: Apparatus with independent power supply, e.g. solar cells, windpower or fuel cells - C02F 2209/42: Liquid level - Y02A 20/124: Water desalination - Y02A 20/212: Solar-powered wastewater sewage treatment, e.g. spray evaporation - 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) - 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) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE ## Abstract A multi-stage distillation system includes multiple stages, and each stage Si includes an evaporator Ei and a condenser Ci. Each condenser includes a steam chamber in pressure-connection with a steam chamber of each evaporator of the same stage. Each evaporator has a steam chamber outlet connected to a spray inlet of the next evaporator Ei+1, and the outlet of the last evaporator En connects to the spray inlet of the first evaporator E1 with a respective fluid line to form an evaporator circuit. Each outlet of each condenser Ci connects to the one spray inlet of the previous condenser Ci−1, and the outlet of the first condenser C1 connects to the spray inlet of the last condenser Cn with a fluid line to form a condenser circuit. A steam line connects between condensers Ci+1 and Ci or between the evaporators En and E1. ## Claims ### Claim at position 1 1-20. (canceled). ### Claim 21 A multistage distillation system, comprising: a plurality of stages Si, where i=1, . . . n, wherein each stage Si works in a higher pressure and temperature range (Δ Pi, Δ Ti) than its ensuing stage Si+1 during operation, wherein each stage Si includes a pressure-tight vessel Vi that contains an evaporator Ei and a condenser Ci, wherein each evaporator Ei includes a spray inlet for introducing and spraying added liquid into the evaporator Ei and a lower outlet for letting out liquid from the evaporator Ei and defines a steam space between the spray inlet and the lower outlet, wherein each condenser Ci includes a spray inlet for introducing and spraying added liquid into condenser Ci and a lower outlet for letting out liquid from the condenser Ci and defines a steam space between the spray inlet and the lower outlet; a pressure-tight steam pipe disposed within each vessel Vi and connecting the steam space of each evaporator Ei with the steam space of each condenser Ci, the pressure-tight steam pipe being configured with a cross section large enough that the pressure Pi in the steam space between the evaporator Ei and the condenser Ci of each stage Si can always achieve equilibrium; an evaporator circuit configured with the outlet of each evaporator Ei connected via a respective pressure-tight liquid line with the spray inlet of the next evaporator Ei+1 except that the outlet of the last evaporator En is connected with the spray inlet of the first evaporator E1; and a condenser circuit configured with the outlet of each condenser Ci connected via a respective pressure-tight liquid line with the spray inlet of the preceding condenser Ci−1 except that the outlet of the first condenser C1 is connected with the spray inlet of the last condenser On; and a pressure-tight steam line having a first end connected with one of the pressure-tight liquid lines between the condenser Ci and the condenser Ci−1 or with the pressure-tight liquid line between the evaporators En and E1, and the pressure-tight steam line having a second end connected with a steam space having a higher pressure P during operation than the pressure in the pressure-tight liquid line to which the first end of the pressure-tight steam line is connected, so as to pressurize the liquid with a higher pressure and convey the liquid. ### Claim 22 (depends on 21) The distillation system according to claim 21, wherein the steam space with pressure P is a steam space of the distillation system. ### Claim 23 (depends on 21) The distillation system according to claim 21, further comprising a first pump connected to the liquid line of the evaporator circuit, and a second pump connected to the liquid line of the condenser circuit, for achieving the prescribed initial pressures of the liquids. ### Claim 24 (depends on 21) The distillation system according to claim 21, further comprising a heater connected to the liquid line of the evaporator circuit before the first evaporator E1 and a cooling aggregate connected to the liquid line of the condenser circuit before the last condenser Cn for achieving the prescribed temperatures in the first evaporator E1 and in the last condenser Cn. ### Claim 25 (depends on 24) The distillation system according to claim 24, wherein the heater and cooling aggregate are together at least partially configured as a heat exchanger. ### Claim 26 (depends on 21) The distillation system according to claim 21, further comprising a plurality of siphons, a respective siphon being arranged in each of the respective liquid lines between the condensers Cn to C1 so as to prevent individual condensers Ci from idling during a system shutdown. ### Claim at position 8 26B. (canceled) ### Claim 27 (depends on 21) The distillation system according to claim 21, wherein each condenser Ci has a gas line connected with a vacuum pump at the end of the distillation path to remove incondensable gases from the steam space of the vessel Vi. ### Claim 28 (depends on 27) The distillation system according to claim 27, wherein the vacuum pump is connected with a pressure-tight steam line, which supplies the vacuum pump during operation by feeding steam to the vacuum pump having a higher pressure P than the steam spaces in which gases are to be siphoned. ### Claim 29 (depends on 21) The distillation system according to claim 21, wherein each evaporator Ei+1 is arranged on a lower level than the preceding evaporator Ei in such a way that the liquid is made to flow from each evaporator Ei into the respectively ensuing evaporator Ei+1 solely by pressure and level differences during implementation of the process, without an electrically operated pump being required for this purpose. ### Claim 30 (depends on 21) The distillation system according to claim 21, wherein each condenser Ci+1 is arranged at such a level by comparison to its ensuing condenser Ci that the liquid is made to flow from the condenser Ci+1 into the respective ensuing condenser Ci by pressure and level differences and/or the conveying force of a steam line during process implementation, without an electrically operated pump being required for this purpose. ### Claim 31 (depends on 21) The distillation system according to claim 21, wherein the condensers C1 and Cn are leveled in such a way that the liquid of the condenser C1 is made to flow from the condenser C1 to the condenser Cn via the liquid line of the condenser circuit by pressure and level differences during process implementation, without an electrically operated pump being required for this purpose. ### Claim 32 (depends on 21) The distillation system according to claim 21, wherein the evaporators En and E1 are preferably leveled in such a way that the liquid of the evaporator En is made to flow from the evaporator En to the evaporator E1 by pressure and level differences and by the conveying force of one or more steam lines via the liquid line of the evaporator circuit during process implementation, without an electrically operated pump being required for this purpose. ### Claim 33 (depends on 21) The distillation system according to claim 21, wherein at least one of the liquid lines and/or at least one of the steam lines is arranged inside of a vessel and/or inside of a steam pipe. ### Claim 34 (depends on 21) The distillation system according to claim 21, comprising a feed in the evaporator circuit for supplying liquid 4 to be distilled, along with an outlet from the evaporator circuit for letting out liquid with a high concentration of residues, as well as a distillate outlet from the condenser circuit for letting out the distillate generated by the system. ### Claim 35 (depends on 21) The distillation system according to claim 21, wherein each steam line and/or each gas line encompasses a valve for regulating the flow rate. ### Claim 36 (depends on 21) The distillation system according to claim 21, wherein at least the vessels of the first condenser C1 and the last evaporator En each encompass a level sensor for determining the level of liquid captured in the respective vessel. ### Claim 37 (depends on 21) The distillation system according to claim 21, wherein a sensor is arranged in the evaporation circuit for measuring the concentration of residues. ### Claim 38 (depends on 34) A method for implementing a distillation process using a distillation system according to claim 34, comprising the following procedural steps: a. monitoring the liquid level in the evaporator circuit and in the condenser circuit; b. monitoring the concentration of residues in the evaporator circuit; c. letting out liquid with a high concentration of residues at the outlet upon the attainment of at least one of the following two conditions: (1) as soon as the liquid level in the evaporator circuit has reached a prescribed maximum level and (2) the concentration of residues in the evaporator circuit has reached a prescribed maximum value; d. letting out distillate from the condenser circuit at the distillate outlet as soon as the liquid level in the condenser circuit has reached a prescribed maximum level; e. letting liquid into the condenser circuit at the feed as soon as the liquid level in the evaporator circuit has reached a prescribed minimum value and/or the concentration of residues in the evaporator circuit has reached a prescribed maximum value; and f. repeating steps a. to e. until the process is to be stopped. ### Claim 39 (depends on 38) The method according to claim 38, wherein each condenser Ci has a gas line connected with a vacuum pump at the end of the distillation path, further comprising the following procedural steps: a. determining the temperature differences Δ Ti in the steam spaces of the evaporators Ei and condensers Ci of the same stage Si; b. removing incondensable gases in the steam space of the condenser Ci through the gas line using the vacuum pump as soon as the temperature difference Δ Ti has reached a prescribed maximum value, until Δ Ti has reached a prescribed minimum value; and c. repeating steps a. and b. until the process is to be stopped. ### Claim 40 (depends on 38) A controller for implementing a method according to claim 38, comprising ports for sensors to read in measuring data, a processor for evaluating the measuring data, as well as ports for changing the settings of valves and pumps. ### Claim 41 (depends on 21) The distillation system according to claim 21, further comprising a plurality of siphons, a respective siphon being arranged in each of the respective liquid lines between each of the respective evaporators E1 to En so as to prevent individual evaporators Ei from idling during a system shutdown.