WO2022121062A1

WO2022121062A1 - Protective compressive inhaler with exhaust purification

Info

Publication number: WO2022121062A1
Application number: PCT/CN2021/000223
Authority: WO
Inventors: Kai TAO
Original assignee: Tao Kai
Priority date: 2020-12-07
Filing date: 2021-11-22
Publication date: 2022-06-16

Abstract

A compressive inhaler, which is defined by: 1) a piston compressing air to a tank, 2) the tank has an internal catalytic converter or other converter/chemical reducer to decrease harmful content in exhaust gas, 3) ideally the tank is temperature controlled, which could be achieved by excellent heat isolation and/or additional heat compensation reduction, so that the temperature is conductive for converting reactions, 4) a cooler, preferably air conditioner, to reduce air temperature before it is supplied to inhale path, 5) insulating or positive pressure, nose-mouse or full-face mask, with flow regulating mechanisms to supply cleaned air to human wearer. Preferably but not exclusively internal combustion engine is used to drive the compressive tank and/or air conditioner. Microcomputers and sensors are used to computerize the machine.

Description

PROTECTIVE COMPRESSIVE INHALER WITH EXHAUST PURIFICATION

Background

The ongoing outbreak of COVID-19 has caused enormous loss to the world and might lead to many crises.

The virus is hard to detect and many people carrying the virus lead life without symptom and continue to spread the virus to others. The dilemma between sustainable economy and pandemic control put people around the world to recurring exhaustions. Even with the advent of vaccine, there have been many discussions of limited protected span and side-effects. It is also impractical to do continuous regular virus test to the population for many reasons.

The mask is one of the primitive means of protection. Adequate protection might require at least additional eye cover, and for medical practitioners full-body needs to be covered in special suit. All parts of a full suit need to be cleaned or replaced periodically, and there are hundreds of millions of these parts required every day. There is also a bottom line that none of these primitive means of protection is 100% safe and a small percentage virus could still penetrate the fabric to reach the human body.

To fully protect the population to ongoing and upcoming virus spreads, this invention sought to build a mobile and affordable gas inhaler, and reduce its price to a fraction of an automobile, and its energy source accessible from common energy supplies.

Compression

The inventor made calculations based on physiological data. Typically human adult inhales at between 20L/min (seated) and 120L/min (moderate sport) gas volume rate, the mobile inhaler must be able to clean this amount of gas in a timely fashion.

The inventor considered several ways of disinfections:

1. By ultraviolet (UV). The most effective spectrum of UV against microorganism is near 265nm and could destroy its structure in seconds. This was however ruled out for two reasons. 1) Near this wavelength the UV unavoidable creates ozone (O3) which could harm human, 2) semiconductor-based UV generators are not efficient enough and have very low emitting rate, whereas glass UV tubes with much stronger emitting power all have mercury gas filled in, and could not be adapted to use within an inhaler.

2. By resistive heating. To ensure that air is indeed cleaned, the temperature of any heating chamber needs to have a distribution that the coolest point still disinfect virus at the location, or the air is stirred, or the air is heated through a long winding path. There however remains a challenge to overcome the high pressure of the hot air when pushing in new air.

The third means is by doing work directly to the air. Consider ideal gas law PV=nRT, where P is pressure, V is volume, n mole number, R Boltzmann constant, T temperature, such a law has several variations in ideal adiabatic, isothermal (in the Carnot cycle) and other processes. A fast compression to the tank gas by the piston is generally considered adiabatic, which follows

where

is the ratio of the gas between heat capacity at constant pressure and at constant volume, which is usually taken to be 1.4. Combining with

we have relation

If the compressive cylinder is designed so that finishing volume of compression is 1/10 of the initial volume and initial temperature is 300K, substitution yield

so the pressure is 25 atmospheric pressure (atm) , and

This rough calculation is validated with real-world data:

1. According to "Evaluation of heating and chemical protocols for inactivating SARS-CoV-2″by Pastorino &Charrel (Unité des Virus

https: //pubmed. ncbi. nlm. nih. gov/32521706/) , "Heating orotocol consisting of 92℃-15min was more effective rather than 56℃-30min and 60℃-60min to achieve 6-log reduction". Similar experiments have been reported by numerous other groups and all support the result. Comparing 92℃ with our calculation, there is a high degree of certainly that the 15-time time could be reduced to less than 1 minute time, and optimistically less than 15 seconds because such high temperature literally "pulverize"microorganisms. We will follow up with supplementary experimental data but use this second-level time frame as an self-evident fact.

2. The temperature of

is well below the melting point of steel (1370℃) , and well below usual heat treatment temperature (860℃) .

3. Ordinary electric air compressors normal pumps air to 8 atm, for laser cutting the specific cooling air compressor compresses up to 16 atm, for the storage of industrial gas like oxygen/argon the tank is designed to hold 150 atm. Our calculated 25 atm can be practically achieved without unduly heavy containers.

Referring to the 20L/min to 120L/min range of normal inhaling rate, 25 atm would require a tank of 0.8L volume for one minute′s use, close to a beverage container. Higher pressure would reduce the tank size and make the device even more portabie. in fact, commerciai air compressors uses only A3 (GB Q235 Q345) level steel which has Young′s modulus of around 200, and steel with more than six times its strength has been used as automobile frames, such better steel would clearly reduce the weight of the cylinder/tank to almost unnoticeable level.

Ordinarily, valves would then be used to allow compressed air to flow into a storage tank. The compression of such small volume of air would take only a fraction of a second, or seconds for a smaller engine/motor.

Power source

Our process increases air temperature by doing work on air during an adiabatic process, and such adiabatic process happens fast to avoid heat loss. The energy source must be able to provide strong burst/spike like energy discharges.

There is a special category of lithium battery, usually called "power lithium batteries", which is used in power tools and electric cars and is capable of discharging at 10C. The "C"here refers to its capacity, so that 10C of a 4200mAh power battery can discharge approximately 42A current under good heat dissipation. It is still deemed less favorable due to some inherent limitations:

1) The invention aims to provide device which protect the wearer for long hours. Calculations reveal that compressing air continuously for hours cannot be sustained by lithium battery of acceptable weight. For example, many electric cars have battery pack weight hundreds of kilograms to reach the same driving distance of 1/10 of its weight of gasoline.

2) The more important problem like in magnetic saturation. Electricity is converted to force by Ampere force

(Lorentz force) , where B is magnetic field strength, /current and /_the length of conductor in magnetic field. It is much easier to increase current by increase voltage than to increase magnetic. Commercially available rare earth magnets has magnetic strength about 1.25T, and if using induced magnetic field to get stronger magnetic field, the saturation strength for electric steels (used in transformers) is 1.8T. These numbers are inherent to the materials and cannot be increased. To achieve the same level of thrust for adiabatic compression, a very heavy electric motor with long axis core and wire winding would be required.

The inventor (Tao, Kai) has skill in machine manufacturing and has disassembled and reassembled Honda CG150 (150cc, China domestic brand) four-stroke motor engines himself, with at least six witnesses at a motorcycle repairing shop. He was successfully in his first attempt of fully disassemble and reassemble and the reassembled engine has run travelled more than 1000 miles between 2019 and 2020 without any glitch. So the following descriptions derive from both theoretical knowledge and hands-on experiences.

For the important theory of combustion and carburetor design, please refer to such as ″The Internal Combustion Engine in Theory and Practice"by Charles Taylor. Electric fuel injection operates with similar principles and we can use microprocessor to achieve optimal stoichiometric mixture proportion.

1) The invention would prefer four-stroke to two stroke engines because four-engine has much better combustion efficiency, burns most of air-gas mixture and ejects least air waste. Carefully controlled air-gas ratio can result in very small clean gas combustion and a healthy adult does not feel the exhausted gas actually irritating.

2) Four-stroke engine is sufficient to provide the power for air compression to 40atm or above.

The theory of carburetor gas flow is built upon the theory of fluid dynamics, the speed of sound, the flow of gas in tubing, among others. The theories of such are complete and could be controlled using microcomputer. The cylinder would have holes punched on that connecting pressure and temperatures (among others) for computer monitoring.

The benefit using combustion engine was to overcome the shortages of other power source like lithium -to provide enough compressive thrust and to work for sufficiently long time.

Waste gas purification

The fuel would require "better" gases, and we will pursue purpose-built refinery for our device, and we allow the use of "green"or "clean" gas, but a 92#or 95# (octane rating) could serve a working minimum.

A typical purification process, for example of a catalytic converter, consist of

Reduction of NOx to N2:

Oxidation to CO2:

Internai combustion engine emit nitric oxide, nitric dioxide and hydrocarbons. Ordinariiy,this wouiopreciude its use in an inhaier machine design, but we choose it after weighing its merit in pandemic controi and its disadvantages. Our design minimizes undesirabie air content by

1) Using computerized carburetor /electric fuel injection to maximize combustion efficiency

2) A catalytic converter is placed at the exhaust outlet to provide a first-round cleaning. Because of the computerized combustion control, exhaust temperature can be controlled close to the prelerred temperature of catalytic conversions, namely, 426℃

3) One or a plurality of catalytic converters inside the compression chamber of storage tank. As our calculation above has shown. a 1/10 compression ideally increases the temperature to 482℃, a slight modification would change that directly to near the sweet spot temperature. It can also be designed to compress to a higher temperature, such as 600℃ or more to disinfect the virus and iet the expansion work in storage reduce the gas temperature. Depending on the material, composition or technoiogy used for the catalytic (or other means) converter, that 426℃ could be different but we will always adjust air to that particuiar tigure.

4) The effectiveness of the purification can be reasoned by a) ordinarily, carburetor has a 90% efficiency at 426℃ temperature. b) only a small fraction (3-5%) of exhaust gas would be sucked in by the compressor c) in the compressed ideal temperature the gas molecules have best reactivity for cataiysis to happen, the high temperature/pressure (25x or more) environment allows for efficient coiiision between gas molecules and cataiytic converter′s surface material, c) the gas would stay with the catalyst converter with time frame of minute (s) rather than when it is existing the first carburetor, another 60x pius increase.

Combined, it would be reasonable to expect that especiaily the second round of conversion would reach reduction rate of somehow an aggregate contribution of {1-90%-10%, 3-5%, 25x, 60x} . The inventor optimistically hopes less than 0.2% of the initial exhaust gas will ultimately be inhaled. We could compare undesirability to someone who passively inhales from a cigarette smoke standing 3 meters away, or unavoidable needs to walk outside in a smog environment. Though impetfect, it provides absoiute, full-body, full-time and convenient protection for vulnerable people, medical practitioners, law enforcement workers, havelers and pivoial groups of the popuiahoe.

The full-body″ protection is meant to use it together with face or face cover, along with protcctive suit. The combustion cngine could provide electricity to power UV tubes, which could be conveniently attached to arms/palms, to disinfect from contact contamination.

Air cooler

The hot air from the cylinder/storage tank needs to be cooled before supplying to human use. Although cooling effect can be obtained by letting gas expansion do the work, such as letting it reversely pushing a piston or overcome spring force(s), and the parameters of piston, spring, real-time temperature, pressure can all be measured and microprocessor can be used to regulate the process, the most predictable and preferred method is to use the an air conditioner. The air conditioner works a heat pump whose mechanical expansion work lowers the coolant′s temperature to cause it evaporate, releasing huge amount of heat, and a second mechanical compression restore the coolant′s pressure-volume state. Using combustion engine as energy source, all aspect of the air conditioning can be precisely controlled.

There could either be one shared combustion engine for both air compressor and air conditioner, switched by a clutch, or unique ones for each.

Novelty and Non-obviousness of disinfection method

The usefulness has been discussed and the presumable safety was established on figures {1-90%=10%, 3-5%, 25x, 60x}, allowing thorough purification of waste gas. The Honda 150cc engine which the inventor reassembled weighs 39 kilogram, removing its gearbox, clutch, starting motor could reduce the weight of cylinder to some 5kg, and the reducing cylinder size of 50cc or less with better steel would allow making cylinders less than 2kg, including all electronics. Combining with air tank and proportionally miniaturized air conditioner, there is a certainty that the machine combined could be made lighter than 6kg, similar to that of a schoolbag. The design allows rapid manufacturing and provides critical population with complete protection from all forms of infectious diseases.

The usefulness and the wide and significant social-economic benefit (cite US patent law) provides one ground for patentability.

For the non-obviousness requirement, we argue that the viability of the solution is not an obvious fact to people skilled in the field.

One close priority is an electric helmet made by 藤井雄 of Japan′s Gunma University, it was reported by Japan′s top mainstream media 朝日新闻 and China′s top web portal SINA.com

( https://news.sina.com.cn/w/2020-07-08/doc-iircuyvk2677269.shtml). It has an electric pump and a filter described as being able to disinfect the air. As of July, the total weight of the device is 1.9kg. I have respect for their work, but have doubts on the effectiveness of disinfection given the "Heating protocol consisting of 92℃-15min was more effective rather than 56℃-30min and 60℃-60min to achieve 6-log reduction" result from Unité des Virus

cited above. In addition, I estimate the device′s operating time span to be only around one hour. It was the work of 藤井雄 and another two professors 桥本诚司、山口誉夫 and teaching assistant 田北启洋. It appears to me that they either ruled out using compression for heating-disinfect, perhaps because cannot find ways to purify waste gas, or lacking multi-disciplinary knowledge to conceive the design.

Russia′s national television station (CCTV translation http: //m. news. cctv. com/2020/04/20/ARTI3rVmOwg9FJGeSypAhBmN200420. shtml) reported using jet fighter′s engine to eject hot air directly to the outside of buses as a queue of buses filing through a road into Moscow. The news specifically pointed out that the air temperature after compression and ejection from jet engine reaches 700℃. Russia had a long and celebrated history of engine design, but as far as the video has shown, the hot air is only used to clean the external side of the vehicles and no attempt was made to produce inhalable air from the engine.

In the USA, there have been many successes to provide alternative ventilator to patients. For example, NASA developed a ventilator named VITAL in 37 days in April 2020 and in their press release said "We are experts in spacecraft production, not just in medical device production, but also excellent engineering, rigorous testing and rapid prototyping are some of our specialties". However, I am not aware of their use of the compression-heating-purifying method. It is hard to imagine that the world′s most authoritative and resourceful experts would let the idea escape them if it was really obvious.

China and world′s largest air conditioner manufacturer Gree produced a type of COVID-19 disinfecting air purifier in March which was widely pubiicized (Tencent news https: //new. qq. com/omn/20200321/20200321AONRYG00. html, product page https://mall. gree. com/goods/product/details? id=1002936617&skuld= 1000265322https://fmall.gree. com/m obile/index. html- /detail? id=1002936617&skid=1000265322&distributionld&distributionltemld=28922&distributionShopld=2 000002215) . The product is described to ionize air so the virus is destroyed. However, it only claims 99%COVID virus reduction in hour period. It was very clearly to me that they employed a much "weaker" level of ionization to avoid ultraviolet′s ozone side effect, but as a consequence required many circulations during the hour long period to partially clean the air again and again. The company′s 2019 domestically sold more than 20 million air conditioners, said to have hire over 12000 employees in R&D ( http: //finance. sina. com. cn/chaniing/gsnews/2020-03-17/doc-iimxyqwa1183583. shtml) , and also make other appliances using compressor as a component, including refrigerators. However, the same compression-heating-purifying idea aiso did not occur to them.

For Germany, their extracorporeal membrane oxygen (ECMO) was widely reported and contributed in the fight against COVID -19 in Wuhan. It also invented the internal combustion engine (Otto engine, 1861) and still provides the best automobile engines. For personnel protection, in 2020′s China International import Expo CCTV reported a air-filtering protective suit from Germany called Air Estetic( http: //m. news. cctv. com/2020/11/05/ARTICSpaND01O20shFLaVuOy201105. shtml) . It clearly also used electricity to disinfect. I believe it is similar to the Japanese helmet in operation and does not achieve the absolute disinfection and long-operating hour as our internal combustion powered device.

These examples are given to show even for the technically most advanced countries, groups, or engine designers themselves, it was not an obvious idea to them to use the compression-heating-purifying method.

I would also like to emphasize that the discovery of this method was result of a combination of unique characters and knowledge. The applicant is a bold inventor and versatile practitioner with sound knowledge in physics, electrical engineering, integrated chip design, computer engineering, programming, engine design and machine tool building (CNC, EDM, pneumatic, etc. ) . The realization that a second round catalytic conversion in dense concentration would effectively eliminate waste gas, was due to knowledge from the derivation of Shockley′s diode equation, than p-type acceptors and n-type donors rapidly form and recombine in a semiconductor p-n junction. Specifically, the semiconductor physics (Clifton Fonstad, Microelectronic Devices and Circuits &Simon Sze, Modern Semiconductor Device Physics) treat ions like gas, the macrostate equilibrium and the catalyst process can be understand using exactly the same principle. Even before conducting experiment to analyze compression tank catalytic conversion efficiency on my ongoing prototype, I could reliably predict its success just as William Shockley concluded in his paper that the p-n junction is a "highly predictable and controllable device".

Besides, the specific range of temperatures we sought to control, and the active heating and cooling mechanisms employed to control cylinder/storage tank temperature, are all purposely designed and are not the side effect of any existing devices.

Hence we have finished our argument of non-obviousness requirement.

Waste gas extraction facility

In PCT/CN2020/000292, we described a compressive inhaler which consist of an energy source driving a piston to adiabatically compress air into a tank, and the high temperature the air attained destroys all infectious microorganisms. For mobility and for use of extended period, internal combustion engine might be used to drive the compression. Although clean/green gasoline might be adopted, there are still some amount of harmful content in the waste gas, and part of them would be drawn into the tank. To cope with that, an additional catalytic converter is placed internal to the tank, and the temperature at the end of the compression, or within the tank, is actively maintained to be around the optimal temperature of the catalytic conversion. The high temperature and high density environment is inductive for reduction reaction so that a very high conversion rate could be achieved, and the user would inhale air in which harmful combustion waste is reduced to minimal.

However, the majority of the waste gas is released into the environment. Particularly when the wearer is sharing space with other people, such as nurse attending patients or in the same office with colleague, the waste gas could be inhaled by those people.

To address this problem, a ventilation system is designed to work with the compressive inhaler. The outlet where the waste gas ejects is located at the bottom of the shoes, usually connected by a pipe to the internal combustion engine. The environment, such as a hospital ward, has its floor fully converted by a grid which is divided into rectangles, underneath each rectangle there is a tube connecting ultimately to an extraction pump. When the wearer walks on the floor, his position is sensed by weight/optical/magnetic/hall effect/sound means, and the valve of the tubes underneath his feet is activated, so any exhaust gas coming out of the bottom of his shoes is immediately drawn away.

In this way, the amount of waste gas in the environment would be practically zero, ensuring safe environment for patients/coworkers.

The shape and pattern of the floor grids could of course be of others, like hexagon. The extraction grid could also be set above on or near the ceiling, and in this case the combustion engine would have a rigid high tube rising to near the ceiling.

Sequential removal of waste gas to negligible trace

Refer to reaction shown in ″Waste gas purification", such a process might not be idealistic. The waste gas might not be of an exact proportion due to variation in factors of {combustion, engine catalytic conversion, environment air flow} , and even the final conversion in the compressive chamber are affected by temperature and other factors.

After the catalytic conversion process within the compressive chamber, we described in previous applications that a heat pump is used to cool the hot mixture to inhalable temperature.

If there are still unwanted waste gas in the content, however small, it is desirable that they can be fully eliminated so out protective inhaler can be suited for use over extended time. The further elimination consists of:

1. Accurate detection of mixture content. This can be achieved using sensors, gas analyzers, etc.

2. For a particular waste gas, such as remaining nitrogen monoxide (NO) , we inject a particular chemical element (for example O2) into the chamber, then trigger the reaction by a spark and that remaining gas is completely eliminated.

3. We design a process so that the successive elimination of waste gas contents do not eliminate with each other. After the sequence, a very clean inhalable fresh air is obtained.

We are actually adding a miniaturized chemically purification plant into our device. It requires that step (1) is accurate, for which we will incorporate state of art sensors such as IR (FTIR, etc. ) gas content analyzers. Then it requires that we can inject precise amount of reactant in step 2) . Most commonly, reactants in 2) would also be gas. Since the whole device is designed to work for long hours so we need to store quite an amount of reactant, they would preferable be in liquid state.

The precise injection of reactant of gas would require drawing micro-millimeter or smaller amount of liquid gas droplets. Drawing gas directly in the liquid phase would be much reliable than in the air phase because density is almost constant in the liquid phase rather than can be varied for many times in the air phase. Also, in air phase to measure air mount one need to measure flow speed, pressure, temperature, and they actually consists of a non-uniform field described by fluid mechanic equations, which greatly complicated the problem.

Therefore we stipulate that the measure of recant is limited to in the liquid phase. Then the problem in step 2) is converted to drawing precise amount of liquid from a chamber.

A short description is that: a purposely designed optical lens system is placed near the nozzle, a pump or fast valve release liquid phase gas in droplets, and the optical system captures the shape of the droplets and obtains the precise measurement. The volume of droplets might vary but is described by equations of liquid tension, vapor pressure and other factors, so they vary with a certain range. The optical measures are ultra-precise to the order of 1/thousands of the droplet volume. Of course, the optical lens system is followed by digital camera and microprocessors for the calculation.

To restrict the droplets to fall in vertical direction, auxiliary means such as using accelerometer to measure reactant storage chamber orientation and using motors to adjust that can be applied.

In step 2) , we might need valves to separate {nozzle, measurement system} from catalytic conversion chamber. Separated by valve from the catalytic conversion chamber, the reactant gas droplets are injected in to a chamber. The temperature and pressure of the chamber would need to be maintained to ensure the droplet remains in liquid phase during the measurement. After that the valve separating the compartment would open to allow it to evaporate and mix with the catalytic converter content, or a piston to push that into the catalytic converter chamber.

By applying a sequence of step 1) and 2) , we would idealistically reduce the content of waste gas to zero. Needless to say, constructing such a system would require consummate knowledge and skill of engine design, fluid mechanics, electronics, optics and chemistry. We regard this as a necessary endeavor since its superiority can completely protect lives from all forms of bio-threats.

Claims

A device to disinfect gas containing infectious microorganisms, in which compression closely or roughly follows an adiabatic process, is used to raise air temperature to destroy microorganisms.
A device of claim 1, in which heated and stored air is cooled by a cooler, preferably air-conditioner type heat pump before being inhaled.
A device of claim 2, in which a shared one or a plurality of internal combustion engines is used to provide energy to compression cylinder and/or air conditioner.
A device of claim 3, in which there is waste gas purifier (s) (such as catalytic converter) inside the compression cylinder/storage tank.
A device of claim 4, in which the temperature of cylinder/tank is controlled to be near the optimal working temperature of the catalytic converter, for example 426℃
A device of claim 1, in which at the end of air compression, or during storage, the temperature is controlled to be definitely higher than a professionally validated instant disinfection temperature of the microorganism.
A device of claim 6, in which the said temperature is higher than 92℃
To cooperate with the use of internal combustion engine for compressing and heat air with infectious macrobiotic content, a floor or ceiling with a grid of waste gas extraction tubes connecting ultimately to a pump.
Under claim 8, a mechanism sensing the location of the waste gas ejection outlet and open the nearest pump tube by valve (etc.) to most effectively remove the waste gas.
Under claim 9, where the gas ejection outlet is located at the bottom of the shoes.
A device of claim 1, which sequentially measures a particular content in the catalytic conversion reduced waste content, and injects particular combinations of reactants into the chamber and initiate a reaction to remove that waste content.
A device of claim 11, in which reactants are injects first in liquid phase to ensure accurate volume measurement.
A device of claim 12, in which an optical lens system is placed near the injection nozzle to precisely measure the droplet volume. The optical lens system is followed by cameras and microprocessors to do the calculation.
A device of claim 11, in which the measurement of gas content is done using infrared sensor, including FTIR.