Patent Application
20240383776
Disclosed herein is a distillation urine processor assembly and method of use thereof.
Space exploration and activities depend on the development of technologies to accommodate long term human habitation in space. Current restraints on space-adapted technologies include limited space, limited storage, and difficulties associated with high complexity equipment.
One of the considerable costs to sustain life in space is the resupply of consumables. These consumables include supplies for equipment maintenance and repair and sustainable food and water sources. A particularly challenging problem is launch of sufficient water to supplement water loss due to humidity loss, oxygen generation, and human waste.
An astronaut produces an average of 1.4 kilograms of water from urine per day. Recapture of water from urine presents an opportunity for substantial cost savings. However, existing urine processor assemblies are technically complex, unfamiliar to potential developers/suppliers, and entail high costs of implementation.
Therefore, the need remains for a simplified, lower cost urine processor assembly.
A distillation urine processor assembly comprises a first collection tank, a heat exchanger, a first separating apparatus, a second separator and a storage tank. The first collection tank is operative to collect urine. The first separating apparatus lies downstream of the heat exchanger and comprises a first separator, at least one pump, and a second collection tank. The first separator is operative to separate urine into water vapor and brine. The at least one pump is in fluid communication with the first separator. The second collection tank is operative to store the brine discharged from the first separator. The second separator lies downstream of the heat exchanger. The second separator is in fluid communication with the heat exchanger. The second separator is operative to separate water from gas. The storage tank lies downstream of the second separator. The storage tank is operative to store water discharged from the second separator.
In one aspect, the assembly further comprises a condenser. The condenser lies downstream of the heat exchanger and upstream of the second separator.
In another aspect, a condenser is integrated into the second separator.
In yet another aspect, the at least one pump is integrated into the first separator.
In yet another aspect, the assembly further comprises a second pump. The second pump lies downstream of the first collection tank and upstream of the heat exchanger.
In yet another aspect, the second separator is a rotary separator.
In yet another aspect, the first separator, the at least one pump, and the second collection tank are arranged in a recycle loop.
In yet another aspect, the first separator apparatus further comprises a filter and a second storage tank.
In yet another aspect, the first separator is a rotary separator.
In yet another aspect, a pump is integrated into the second separator.
A method of processing urine using a distillation urine processor assembly comprises introducing urine into the assembly. The urine is passed through a heat exchanger. The urine is pumped through a first separator that lies downstream the heat exchanger. The urine is separated into brine and a mixture of water vapor and gas in the first separator. The brine is pumped from the first separator through a filter. The water vapor and gas is discharged from the first separator through the heat exchanger where the heat from the water vapor and gas is transferred to the incoming urine. The mixture of water, water vapor, and gas is discharged through a second separator; where the second separator is operative to separate water from the gas. The water is obtained from condensation of the water vapor.
In an aspect the water discharged from the second separator is stored in a storage tank.
In another aspect, the gas discharged from the second separator is vented to the environment or stored for further processing.
In yet another aspect, the urine is heated in the heat exchanger via heat obtained from a mixture of water vapor and gas discharged from the first separator.
In yet another aspect, the mixture of water, water vapor, and gas is discharged from the heat exchanger to a condenser; where the condenser lies downstream of the heat exchanger and upstream of the second separator.
In yet another aspect, the second separator brings about the separation of water from gas via filtration or membrane separation.
In yet another aspect, the second separator is a rotary separator.
The above described and other features are exemplified by the following FIGURE and detailed description.
Referring now to the FIGURE, which is an exemplary embodiment, and wherein the like elements are numbered alike.
The FIGURE is a schematic of an embodiment of an exemplary simple distillation urine processor assembly.
Disclosed herein is a simple distillation urine processor assembly that processes urine for re-use. The urine processor assembly provides a functional system under demanding environmental conditions including microgravity or zero gravity environments. The assembly utilizes a simple distillation cycle with a phase separating apparatus and recirculating functionality.
The streamlined design of the assembly comprises a storage tank for urine storage before processing. The urine is then discharged from the storage tank through a heat exchanger into a phase separating apparatus. During phase separation, the water is evaporated and a concentrated brine solution is discharged into a collection assembly and can be recirculated through the phase separating apparatus as desired to increase efficiency of the water extraction process. The evaporated water and non-condensable gases from phase separation are charged to the heat exchanger and then a downstream condenser where residual water vapor is condensed to liquid water. The condensed water and gases are pumped out of the condenser into a second phase separator. The resultant gas is vented or stored for later processing and the water is delivered to storage or a water processor.
“Ambient pressure,” as used herein, refers to pressure of a surrounding environment.
“Brine,” as used herein, refers to mixtures and solutions of salts and water.
“Product fluid” refers to water, water vapor, or a combination thereof. The product fluid is devoid of salts or oils present in urine.
“And/or” as used herein means “and” or “or.”
“Microgravity” as used here means near weightless of approximately 1/1,000,000 of Earth's gravity.
“Urine” as used herein refers to untreated and/or treated urine.
The FIGURE depicts an exemplary simple distillation urine processor assembly 100 (hereinafter assembly 100) that comprises a urine inlet 101, a storage tank 104, a heat exchanger 107, a first phase separating apparatus 114, a condenser 118, and a second separator 120. In certain embodiments, the urine inlet 101 lies upstream of the heat exchanger 106 and is in fluid communication with it. Disposed between the inlet 101 and the heat exchanger 106 is a storage tank 104 and an optional first pump 106. The first pump 106 facilitates the transportation of urine from the inlet 101 to the heat exchanger 107. The heat exchanger 107 heats urine that is to be charged to the first separating apparatus 114. The heat exchanger 107 exchanges heat between a heated product fluid (water, water-vapor, or a combination thereof) received from the first separating apparatus 114 and urine that is to be treated in the first separating apparatus 114. Urine is transported from inlet 101 to the first separating apparatus 114 via stream 103.
Within the assembly 100, the heat exchanger 107 is in fluid communication with a first separating apparatus 114. The first separating apparatus 114 facilitates the separation of the urine into brine and water or brine and water-vapor.
The first separating apparatus 114 comprises an optional second pump 108, a first separator 109, an optional third pump 111, a second collection tank 112 and a filter 113. In one embodiment, at least one of the second pump 108 or the third pump 111 are present in the separating apparatus 114. In an alternative embodiment, the first separating apparatus 114 can comprise no pumps. In an embodiment, the first separator 109 can integrate a pumping function.
In an embodiment, the first separator 109 lies downstream of the second pump 108 and upstream of the third pump 111. The second collection tank 112 and the filter 113 lie downstream of the separator 109. Fluid emanating from the separator 109 is transported to the pump 111, storage tank 112 and filter 113 via stream 110.
In an embodiment, the second pump 108, the first separator 109, the third pump 111, the second collection tank 112 and the filter 113 can lie in a recycle loop 116. A recycle loop is one where each component of the loop can be both upstream and downstream of any other component in the loop. For example, the first separator 109 is both upstream and downstream of the filter 113 because fluid discharged from the first separator 109 is fed to the filter 113, while at the same time fluid discharged by the filter 113 is fed to the first separator 109. For increased extraction of water from the brine, the brine can be re-cycled through the first separating apparatus 114 within the recycle loop. A portion of the product fluid can be continuously removed downstream of the first separator 109 from the recycle loop and charged to the heat exchanger 107 via stream 115.
Product fluid discharged from the first separating apparatus 114 is transported to the heat exchanger 107 via stream 115. Heat generated in the product fluid during phase separation is exchanged with incoming urine in the heat exchanger 107. This heat exchange improves the efficiency of the assembly 100. In an embodiment, the product fluid after exchanging its heat in the heat exchanger 107 is discharged to a second separator 120 via streams 117 and 119. In an embodiment, the product fluid after exchanging its heat in the heat exchanger 107 is discharged to a condenser 118 via stream 117.
Downstream of the heat exchanger 107 lies a condenser 118, a second separator 120 and a storage unit 124. The condenser 118 lies upstream of the second separator 120, which lies upstream of the storage unit 124. The condenser 118 cools the product fluid so that it exists primarily in liquid form (i.e., liquid water). The liquid water may be discharged from the condenser 118 to the second separator 120 via stream 119. An optional fourth pump 121 may be located downstream of the second separator 120 and facilitates transportation of the purified water into the storage unit 124 via stream 122. The second separator 120, the fourth pump 121, and the condenser 118 can be combined within a single unit if desired. In some embodiments, the second separator 120, fourth pump 121, and condenser 118 can be enclosed together in a housing.
The collection tanks 104 and 112 can be the same or different. A collection tank 104 or a collection tank 112 can be a pressure-controlled storage tank, such as a bellows tank, a bladder tank, or a diaphragm tank. In some embodiments, the collection tanks can be enclosed in a housing to prevent fluid escape. During storage and/or before entry of the urine into the stream 103, the urine can be chilled via mechanical refrigeration or other suitable cooling techniques. In some embodiments, the collection tank 104 includes absorptive beds and other materials for stabilization and storage of the urine. In some embodiments, the collection tank 104 and/or collection tank 112 can be pressurized above the operating pressure of the system to drive fluid into the system. In an alternative embodiment, the collection tank 112 can contain suitable absorbents such as ion exchange resins to facilitate removal of salt from the urine and brine.
The streams 103, 110, 115, 117, 119, 122, and 123 that transport urine, brine and product fluids (water, water-vapor, or a combination thereof) comprise conduits that contain stainless steel, titanium, nickel-chromium-molybdenum alloys, titanium alloys, fluoropolymers, and the like, or a combination thereof. Suitable fluoropolymers include polytetrafluoroethylene, perfluoroalkoxy alkanes (PFA), fluorinated ethylene propylene (FEP), polyaryletherketone polymers, chlorofluoropolymers, and fluorocarbon rubbers. In some embodiments the streams 103, 110, 115, 117, 119, 122, and 123 may comprise the same materials or different materials. The conduits can withstand pressures of zero to about 300 kilopascal (kPa), of about zero to about 200 kPa, of about zero to about 150 kPa. The flow rate of the urine, brine and fluids through the conduits can be about up to approximately 15 milliliters per minute (mL/min), up to approximately 13 mL/min, up to about 5 mL/min.
The urine flows through a heat exchanger 107 and is heated by heat generated from the product fluid discharged from the separating apparatus 114. The heat exchanger 107 increases efficiency of the separation process by pre-heating the urine close to saturation temperature before discharge into the first separator 109. The heat exchanger 107 can be a regenerative or a recuperative heat exchanger where the urine absorbs the heat of the water vapor, liquid, and gas mixture discharged from the separating apparatus 114. The heat exchanger can be a parallel flow heat exchanger, a counter flow heat exchanger, or a cross-flow heat exchanger.
As noted above, the assembly 100 comprises a plurality of pumps-first optional pump 106, second optional pump 108, third optional pump 111 and fourth optional pump 121. In an embodiment, the system comprises at least one pump. In an embodiment, the first separating apparatus 114 comprises at least one pump and the second separator 120 is in direct fluid communication with at least one pump. Pumps used throughout the urine processor assembly can differ in design and type based on the area of use within the assembly 100. Suitable pumps include bellow pumps, diaphragm pumps, peristaltic pumps, scroll pumps and gear pumps. In an embodiment, the pumps are peristaltic pumps. In an embodiment, the second pump 108 can be optionally integrated into the heat exchanger 107 or moved upstream of the heat exchanger 107. In some embodiments, the second pump 108 is located downstream of the heat exchanger 107.
The first separator 109 and the second separator 120 can be the same or different. The separators can be rotary separators, membrane separators, inertial separators, or any separator suitable for separation of brine from water and/or water vapor in microgravity to zero gravity conditions. In alternative embodiments, the separators can be gravity-based separators. When the first separator 109 or the second separator 120 is a rotary separator, separation occurs via the imposition of rotational inertia imposed on the fluids and their relative densities. The rotary separator provides phase separation during rotation under ambient pressure while heat is added to the urine (i.e., the temperature is increased). Membrane separators can separate water from gases via a screen or membrane with hydrophobic or hydrophilic properties. In one embodiment, the first separator 109 is a rotary separator, while the second separator 120 is a membrane separator. In alternative embodiments, the first separator 109 is a rotary separator with integrated heaters to simultaneously boil and separate the urine/brine from the water vapor. In one embodiment, a heater integrated into the first separator 109 and/or a preheater upstream of the first separator 109 receives heat via electric-powered heaters. In another embodiment, a preheater upstream of the first separator 109 is a recuperative heat exchanger 107. The first separator 109 can perform both the function of boiling the urine and the function of separating the liquid urine and water vapor. In another embodiment, the first separator 109 and the second separator 120 are both rotary separators.
The filter 113 can be located upstream or downstream of the brine collection tank 112 as shown in the FIGURE. In some embodiments, the filter can be integrated into the brine collection tank 112. In alternative embodiments, multiple filters can be present in the first separating apparatus 114. For example, a coarse filter (e.g., 100 micrometers pore size) can be used upstream of a less coarse filter (e.g., 10 micrometers pore size). The filter 113 can comprise internal mesh elements sized to the desired pore size. Suitable materials for the internal mesh of the filter 113 include stainless steel, titanium, polytetrafluoroethylene, or a combination thereof. In another embodiment, the filtrate from filtering the brine can be re-cycled through the separator 109 to increase the overall yield of water from the urine. In an alternative embodiment, the filter 113 can comprise suitable absorbents such as ion exchange resins to facilitate removal of salt from the urine and brine.
As shown in the FIGURE, the assembly 100 can intake urine directly for processing or store the urine for later use. The flow of urine and its byproducts through the assembly 100 are indicated by arrows 102. Urine is taken into the system at an inlet 101 and transported through conduits 103, 110, 115, 117, 119, 122, 123, and so on, as described in detail below. The urine can be pre-treated prior to intake into the assembly 100 or added directly to the assembly 100. Suitable pretreatment methods can comprise a treatment via oxidative processes (e.g., ozone) or treatment with chemicals including acid, hexavalent chromium, quaternary amines, and combinations thereof. Suitable acids for pretreatment include acetic, benzoic, citric, glycolic, hydrochloric, nitric, phosphoric, sulfuric, or a combination thereof. In some embodiments, the pH of the urine can be adjusted to a pre-set level before processing.
Urine can be fed directly into the assembly 100 at inlet 101 and stored in a collection tank 104. In alternative embodiments, the assembly 100 can have an optional entry point 105 after the collection tank 104, such that the urine is processed directly through the assembly 100 without storage. In some embodiments, the inlet 101 can be via the various waste sources, such as direct incorporation to the universal commode system (space toilet). Pumps can be optionally placed before and/or after a collection tank 104.
In embodiments where the urine is stored before processing, the urine can be stored in the collection tank 104. When the urine is ready for processing, it is pumped through the heat exchanger 107, where it is heated by the product fluid discharged from the first separating apparatus 114. After passage through the heat exchanger 107, the urine enters the first separator 109, where it is separated into brine and water and/or water vapor.
The brine residue can be discharged into a collection tank 112 and/or can be filtered in filter 113 and re-cycled through the recycle loop of the first separating apparatus 114. The vapor and gases exiting the first separator 109 is discharged via stream 115 to the heat exchanger 107. After passage through the heat exchanger, the mixture of water, water vapor, and non-condensable gases pass through a condenser unit 118. The water and non-condensable gases are pumped via stream 119 to the second separator 120. The gas is vented out via stream 123 and the water is separated via stream 122. The water is then collected in a storage unit 124 or sent to further processing. As noted above, pumps can be used throughout the system to drive the flow of the materials.
The assembly 100 provides the capability to reduce water loss to urine. As each human produces approximately 1.4 kilogram of water per day, the costs to provide the equivalent replacement water will be reduced by implementation of this assembly. The assembly provides a simple distillation cycle with limited components to reduce system complexity and production costs. The assembly 100 can function in a microgravity environment and can collect greater than 90% of the water in crew member urine for processing and re-use. In some embodiments, the assembly 100 can be utilized in standard gravity to zero gravity conditions or environments with greater gravitational forces than standard gravity.
When the separator 109 is a rotary separator, the separation occurs via the imposition of rotational inertia imposed on the fluids and their relative densities. During the phase separation, water evaporates and urine is concentrated into a brine solution. The brine is pumped out of the first separator 109 into stream 110 via the third pump 111. In some embodiments, the pump 111 is integrated into the first separator 109. In some embodiments, the brine is stored in a collection tank 112 before further processing. In some embodiments, the brine is partially separated in the collection tank to facilitate re-cycling of the liquids (present in the brine) through the first separator 109 within the recycle loop 116. In this manner, the collection tank 112 can serve as a separating chamber for the liquid and solid components of the brine. The brine within the collection tank 112 can be separated by gravitational forces and/or filters.
After phase separation, the water vapor and other gases are discharged from the first separator 109 via stream 115. In some embodiments, the water vapor and other gases are driven from the first separator 109 by a pump. In some embodiments the pump can be integrated into the heat exchanger 107. Within the heat exchanger 107, the water, water vapor and gas mixture exchange heat with incoming urine. The addition of a heat exchanger improves the efficiency of the process by warming the incoming urine stream 103 for phase separation and cooling the water vapor stream 115.
After the water, water vapor, and gas mixture is discharged from the heat exchanger 106, the mixture flows via stream 117 into the condenser 118. The condenser 118 condenses the remaining water vapor to provide a water/gas mixture.
After passing through the condenser 118, the water and gas mixture is ready for phase separation. The mixture is pumped via stream 119 into another separating apparatus (the second separator 120). A pump can be downstream of the condenser 118 or integrated into the second separator 120. The second separator 120 can be a membrane separator or a rotary separator. In some embodiments, the second separator 120 can integrate the pump 121 and the condenser 118 functionality in an individual apparatus. In some embodiments, the combined functionality can be enclosed together within a housing.
After phase separation, the liquid water passes out of the second separator 120 via stream 122 and can be stored in a collection tank 124 or passed through to further processing. In some embodiments, the water can be filtered before exiting the urine processor assembly 100 via the stream 122.
After phase separation, the gases flow out of the second separator 120 via stream 123 and are vented to the cabin, expelled from the cabin, are stored for later use, or undergo further processing. In some embodiments, the gases can be filtered before exiting the urine processor assembly 100.
The distillation urine processor assembly provides an efficient and lower cost urine processing assembly. Use of the distillation urine processor assembly provides collection of about 90% of water from urine. Furthermore, the assembly provides urine processing functionality with component simplification and a reduced number of components from existing urine processors to ease manufacturing and decrease production costs.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the invention without departing from essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
