Power plants – Internal combustion engine with treatment or handling of... – Having retainer or flow director for exhaust gas condensate
Reexamination Certificate
2001-12-19
2003-06-24
Denion, Thomas (Department: 3748)
Power plants
Internal combustion engine with treatment or handling of...
Having retainer or flow director for exhaust gas condensate
C060S274000, C210S694000, C210S669000, C210S900000
Reexamination Certificate
active
06581375
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an apparatus and method for the recovery and purification of water from the exhaust gases of internal combustion engines, such as those used in land transit vehicles, (e.g., cars). More particularly, an on-board, portable device produces potable water from vehicle exhaust gases.
BACKGROUND OF THE INVENTION
Several devices have been utilized over the years to attempt to provide a feasible system for producing potable water from vehicle engine exhaust. These attempts have been generally unsuccessful.
Combustion of diesel, kerosene, gasoline, LP gas or other fossil fuels in an internal combustion engine produce water vapor, which is expelled with the exhaust gases. The present invention allows for the recovery of that water to provide a source of water for potable and other uses. The engine exhaust emissions vary as a function of fuel type and composition, as well as the fuel:air ratio, the type of engine and mode of its operation, and also factors such as ignition timing, cylinder design and fuel additives. Although the relative concentrations of various exhaust components may change depending on the mode of engine operation, generally the nature and content of exhaust remains within a predictable range. It would be useful to be able to capture this water vapor and turn it into drinkable water, particularly for military operations or travel in hostile environments (e.g., desert areas).
The concentration of water vapor in exhaust gases of either gasoline or diesel engines or turbines ranges up to about 10% by volume. Upon cooling the exhaust gases below its dew point, i.e. about 100° F., water begins to condense. Some gases present in the exhaust, such as oxygen, nitrogen and hydrogen, do not condense. The other exhaust components, such as hydrocarbons, sulfur dioxide, nitrogen oxides, carbon dioxide and particulates and suspended solid matter, other dissolved organic and inorganic matter (including metals), contaminate the condensed water by dissolving in or condensing with the water vapor and must be removed to obtain a potable water product. The treatment apparatus for the recovery of potable water from the engine exhaust must condense the water vapor, remove the particulates, and purify the water produced therefrom.
Vehicle exhaust gases and the condensed water produced therefrom are very corrosive. The untreated water that is recovered from the exhaust has a pH of about 3 and, in combination with high temperatures, corrosion easily occurs in pits and crevices of a heat exchanger, ducting and ancillary equipment used to condense it. High exhaust temperatures and the elevated ambient temperatures that prevail under desert/arid conditions exacerbate the rates of chemical attack on materials. Hence, the selection of materials for the components is extremely important.
Attempts to recover drinking water from exhaust gases of vehicles have heretofore been unsuccessful because the purification of the water was not considered technically and commercially feasible (i.e., the apparatus was too large, the impurities were too high and/or the process was too expensive).
SUMMARY OF THE INVENTION
In brief, the present invention relates to a method for recovering potable water from the exhaust gases of an internal combustion engine, comprising the steps of:
(a) cooling said exhaust gases so as to cause water to condense from said gases (for example, utilizing heat exchangers);
(b) passing said water through one or more particulate filters having a maximum pore size of from about 0.1 to about 10 microns;
(c) passing said water through one or more activated carbon beds (a preferred one sequentially combining a wood-based carbon having a majority of pores in the range of from about 17 to about 40 Å, with a coal-based water-treatment carbon having an average pore size of from about 6 to about 20 Å—the wood-based carbon preferably made by phosphoric acid activation and treated to minimize the amount of phosphorous released into the water); and
(d) passing said water through one or more ion exchange resin beds (a preferred one being a mixed bed of highly acidic and strongly basic type 1 ion exchange resins with low organics and particulate contaminants with high cation and anion exchange capacity).
Optionally, a buffer such as sodium bicarbonate or a base such as sodium hydroxide may be added to decrease water acidity. The sodium bicarbonate may also improve the taste of the water. These additions may be carried out before either the carbon filtration or the ion exchange resin filtration steps.
This system can provide potable water having TOC less than about 0.5 ppm, an inorganic content less than about 2 ppm, and a pH between about 6 and about 8. The potable water can be produced at a rate of at least about 0.5 gallons of water per gallon of engine fuel combusted.
The present invention also includes an apparatus for recovering potable water from the exhaust gases of an internal combustion engine comprising a means for connecting said apparatus to the exhaust portal of said engine (preferably via the catalytic converter); a means for cooling the exhaust gases so as to cause the water in said gases to condense; a means for collecting said water and channeling it to a purification system which comprises one or more particulate filters having a maximum pore size of from about 0.1 to about 10 microns, one or more activated carbon beds, and one or more ion exchange resin beds; and means for collecting the water which has passed through said purification system.
More specifically, this invention relates to a portable apparatus and the method of recovery and purification of potable water from vehicle exhaust gases. Water can be produced at a rate of at least about 0.5 gallons/gallon of diesel using a 6.5 liter diesel engine with a compression ratio of 21:5:1 and a Brake Mean Effective Pressure (BMEP) of about 300 psi, as is standard issue in a HUMVEE, or “HMMWV” United States armed forces vehicle, while having only a small (i.e. <7%) effect upon the engine performance of the vehicle. A combination of particulate filtration to remove solids, treatment by activated carbon to remove organic compounds and some inorganics, and treatment by ion exchange resin to remove ionic species, provide effective removal of toxic and other contaminants to produce potable water having a purity which exceeds the EPA drinking water standards, as well as the DOD TB MED 577 tri-service water quality standards for long-term consumption.
The activated carbon material used in the instant invention removes essentially all of the organic contaminants, even though some are present at concentrations in the ppb range. The water purification step involves passing the water condensed from the exhaust gases having a high concentration of Total Organic Carbon (TOC) materials of from about 50 to about 250 mg/L and a pH of about 2.8, through a particle filter and an activated carbon filter to obtain TOC levels in a range of from about 3 to about 100 mg/L. The resulting product is then passed through an ion exchange resin to remove metals, inorganic, acidic, and remaining organic contaminants. The filtered water samples have a TOC content below detectable limits (BDL) which is 0.5 mg/L for current EPA drinking water regulations and as low as 0.1 mg/L in some instances. This is a significantly lower TOC than a control sample obtained from the local municipal water supply (2.6 mg/L). Moreover, the filtered samples did not contain any of the hazardous organics mentioned in the EPA's drinking water rules.
The present invention recovers potable water from engine exhaust by manually or automatically diverting a desired portion of the exhaust gas stream to the water recovery system. The exhaust gas is preferably first passed through the vehicle's catalytic converter. The catalytic converter generally contains catalyst consisting of platinum metals, transition metals or mixtures and oxides deposited either on alumina extrusions or honeycomb-type monolithic supports. The cata
Jagtoyen Marit
Kimber Geoffrey M.
Denion Thomas
Frost Brown Todd LLC
Lexington Carbon Company LLC
Nguyen Tu M.
LandOfFree
Apparatus and method for the recovery and purification of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for the recovery and purification of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for the recovery and purification of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3163079