JP2005021853A - Exhaust gas control device in internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate CO<SB>2</SB>in exhaust gas from an internal combustion engine as a measure against global warming. <P>SOLUTION: A CO<SB>2</SB>, H<SB>2</SB>O, N<SB>2</SB>-separator is shown as item 101 in the figure. The exhaust gas from the internal combustion engine is cooled below 100°C by a heat exchanger and introduced into a cyclone type centrifuge to selectively separate and eliminate H<SB>2</SB>O and N<SB>2</SB>, respectively, to take out only CO<SB>2</SB>by this device. CO<SB>2</SB>is separated into CO+O<SB>2</SB><SP>-</SP>plasma by an AC high voltage plasma (atmospheric pressure, 1,200-2,500°C)generator (item 102 of the figure). Only O<SB>2</SB><SP>-</SP>is caught and separated by an electric field type separator (item 103 of the figure). C is separated from CO and fixed by a catalytic filter (item 104 of the figure, filter temperature 500-1,000°C) of iron (or metal strip, rare earth metal with spattering-evaporated Ni, Pt and carbon thin film). CO gas passing through the catalytic filter and 1/2 O<SB>2</SB>separated from CO are returned to a combustion part(item 105 of the figure) of the engine and subjected to recombustion to increase the efficiency. Thus, CO<SB>2</SB>can be removed from the exhaust gas of the internal combustion engine. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention is a technique for significantly reducing CO2 in the exhaust of an internal combustion engine or the like that generates CO2 by its operation. .

Conventional internal combustion engines such as automobiles have improved fuel efficiency and reduced CO2 by improving combustion methods (lean burn), reducing vehicle weight (using Al, Mg), etc., but dynamic technological innovation cannot be expected in the future.

Fuel cell electric vehicles are also being developed, but at the stage of producing hydrogen, they use electricity (electrolysis of water) and emit a lot of CO2.

Hybrid vehicles also seem to contribute to CO2 reduction in terms of fuel consumption, but in fact, they use a lot of electric power and generate a lot of CO2 at the stage of manufacturing rare earth metal powder (vacuum melting, gas atomization) of hydrogen storage battery electrode materials.

In the power supply industry, the shift to the combined cycle, pumped-storage power generation, etc., and the development of new energy such as fuel cells, solar power generation, wind power generation, etc. have not progressed as expected, and they have not completely separated from nuclear power
JP2002-129949 JP2002-266626.

Reduce CO2 emissions of greenhouse gases that cause global warming. Most of this CO2 is generated by the operation of an internal combustion engine or the like. Therefore, the reduction is required to be a CO2 reduction device applicable to this internal combustion engine.

First, H2O was liquefied and separated from the 202,207 exhaust gas shown in Fig. 2 using a H2O, N2 separator with a condenser (the temperature of the exhaust gas was lowered to less than 100 ° C using a radiator heat exchanger). Next, N2 is separated with a cyclone separator. As a result, H2O and N2 are separated from the exhaust gas composed of CO2, H2O, and N2, and are discharged into the atmosphere.

High pressure CO2 plasma (atmospheric pressure, 1,000 ~ 2,000 ° C.) in FIG. 3 shows a generator to separate the CO2 to CO + O ^2-. An alternating electric field 302 (frequency variable from 0 to 10 kHz) suitable for CO2 decomposition is applied between 301 rod-shaped (for example, W + Ta) electrodes and 304 cylindrical electrodes, and 303 CO2 is converted to 306 CO + O ²⁻ plasma. Convert to

The electric field system O ² -separation apparatus shown in FIG. 4 separates and traps O ²⁻ from a mixed plasma gas of CO and O ²⁻ by an electrode 402 charged to a positive potential by a power supply 401 and discharges it as an O 2 gas to the atmosphere.

A temperature controller 501 shown in FIG. 5 heats and cools CO to a temperature at which the efficiency of the catalyst 503 is highest.

An iron (or Pt, Ni, carbon deposition wire, rare earth metal) catalyst filter 503 shown in FIG. 5 precipitates and fixes C from CO gas. With 502 H2 flushing devices.

The following action eliminates CO2 from the exhaust gas of the internal combustion engine, etc., introduces the exhaust gas of the internal combustion engine etc. into this apparatus, separates and discharges H2 O and N2 with the separator of FIG. gas separated into CO and O ^2- plasma by a plasma generating apparatus of FIG. 3, 0012-3 O ^2- as 1 / 2O2 at field separation system of FIG. 4 the CO and O ^2- mixed plasma The CO gas discharged from the system and remaining in 0012-4 is brought to an appropriate catalytic reaction temperature by the 501 temperature controller shown in FIG. 5, and then led to the catalyst filter shown in FIG. In addition, CO2 and CO gas are not discharged from the cycle because residual CO and 1 / 2O2 generated by carbon deposition are returned to the input of the internal combustion engine and reburned.

The CO2, H2O, N2 separator shown in Fig. 2 is a device that separates and discharges H2O, N2 from exhaust gas from an internal combustion engine or the like. In order to keep H2O from exhaust gas, the heat exchange system (conventional radiator) H2O separator is used in order not to reduce the thermal efficiency of internal combustion engines. A cyclonic separator is used to separate N2. The capacity consists of a water-cooled heat exchanger that can cool the exhaust gas below 100 ° C to separate the water vapor in the exhaust gas by dew point, and a cyclone that can centrifuge N2 from CO2.

The high-pressure (atmospheric pressure) plasma generator shown in Fig. 3 decomposes 302 CO2 gas into 306 CO, O ^- plasma. The oscillation frequency is 0 to 10 kHz (varies depending on the electrode shape and arrangement of each device). Select a device with a conversion rate of 70% or more. Consider the life of the device and make it from high alloy alloys such as Hastelloy to avoid soot precipitation in this part. The output of the high-frequency plasma generator input power supply 302 is about 1 to 3 kW (with water cooling or other cooling device if necessary).
In addition to DC plasma torches, inductively coupled plasma torches and microwave plasma torches that do not require electrodes can be used for torches (301, 304).
Here, pulse discharge and high frequency discharge type were adopted to stabilize the sustained glow discharge.

Electric field type O ² -separator (Figure 4). The output of the DC power supply 401 is about 0.1 to 1 kw (for automobiles). Again, high alloy alloys such as Hastelloy are recommended for the components.

Fig. 5 shows the CO gas temperature controller and catalyst (C fixing device). 501 is a water-cooled heat exchange system, and CO gas is set to a temperature where the ability of the catalyst can be exerted most in the range of 500 to 1,000 ° C.
503 in FIG. 5 is a catalytic C deposition apparatus. In terms of price, it is recommended to use multiple layers of Fe nets or corrugated products of Fe strips, but Pt, Ni, other rare earth elements, or C sputter-deposited on these materials can also be used. The net is made about 50 mesh, and this is layered and used as a filter. In order to reduce the scale of the surface of the new filter when the filter is replaced, it has a mechanism that performs H2 flushing at the operating temperature. Here again, a high alloy alloy such as Hastelloy is used for components other than the filter. The C precipitation device has a plurality of types, and when one set is clogged, it has a mechanism that automatically switches the circuit to the next catalytic filter device (pressure detection etc.).

Various sensors and control devices (not shown). It has a device (ECU) that detects the CO, CO2 concentration and temperature in the exhaust gas and controls the conditions of each part.

A 500cc displacement diesel engine, a 10kW Sanzo synchronous generator, the device of the present invention shown in Fig. 2-5, and various sensors were used as test equipment. The exhaust system used was the system of the present invention (Fig. 1) and a system that does not go through the exhaust gas treatment device (not shown).

. Output from internal combustion engines and CO2 emissions. As shown in Fig. 6, in the conventional apparatus, the CO2 emission increases as the engine output increases, whereas the CO2 emission of the present invention changes substantially at a low level regardless of the output level. .

Capacitor temperature and moisture capture rate in exhaust gas. As shown in Fig. 7, the moisture trapping rate increases as the gas temperature is lowered, but if the gas temperature is lowered too much, the ability of the radiator has to be increased, which is not reasonable.

.Plasma current and CO conversion efficiency. As shown in Fig. 8, the CO plasma increases as the plasma current increases. This test was performed at a plasma current of 150A and a frequency of 60Hz.

Efficiency of electric field O ² -separator. Since the search rate is 100V as shown in FIG. 9, this test was conducted at 100V.

Conditions for C to precipitate from CO. As shown in FIG. 10, a characteristic having a peak between 500 and 1,000 ° C. is shown. The test was conducted at 700 ° C.

FIG. 11 shows the engine output when the present invention is used. When using the present invention, the output is reduced to about 50% of the conventional value (this is not possible in principle).

Fields shown in claims 1-1 to 7. Especially when applied to automobiles, gasoline or diesel can be used as they are, so the current infrastructure (fuel refinery, stand, etc.) can be used as it is. In contrast, fuel cell vehicles and electric vehicles require new infrastructure.

Outline of equipment configuration; CO is extracted from exhaust gas and C is deposited and fixed with a catalyst. CO2, H2O, N2 separator; Selectively separate H2O, N2 from exhaust gas and discharge. CO + O2 ^- separated plasma generator; CO2 is passed during discharge to form CO and O2 ^- plasma. Electric field type O2 separator; O ²⁻ is selectively separated from the CO and O ²⁻ plasma of FIG. 3 by an electric field. Temperature controller and catalyst C immobilizer; adjust the CO gas temperature to the best working temperature of the catalyst. The catalyst is arranged in multiple layers in a filter manner to ensure capture of C. Engine speed and CO2 emissions (conventional and present invention) Capacitor temperature and moisture capture efficiency in Figure 2 above Conversion efficiency to plasma current and CO in Figure 3 above Electric field voltage and O ^2- separation amount in Fig. 4 above CO gas temperature and C precipitation in Figure 5 above Engine output when using the present invention

Explanation of symbols

101.Radiator, cyclone separator
102. High pressure plasma generator
103. Electric field type O ^2- separator
104.Catalyst (Fe etc.) filter
A circuit that returns unreacted CO and O2 generated by the reaction to the combustion section.
201.CO2, H2O, N2 gas input
202.Exhaust gas cooling chamber
203.Cooling water
204.H2O collection net
205.H2O (L)
206.CO2 gas
207.Cyclone
208.N2 (Exhaust)
301.Bar electrode
302.AC power supply
303.CO2 gas
304.Cylindrical electrode
305.Nozzle
306.CO + O ²⁻ Plasma
401 DC power supply
402.Electrode
501. Temperature controller
502.H2 flushing device
503.C Precipitating catalyst

Claims (7)

An apparatus characterized by selectively separating H2O and N2 in exhaust gas of the internal combustion engine or the like shown in FIG. 1 with a radiator and a cyclone 101 in FIG. And wherein the decomposed into CO + O ^2-in AC high voltage plasma generating apparatus of said claim 1 1 in 102 remaining CO2 gas. 3. The apparatus according to claim 2, wherein the oscillation frequency of the high-voltage plasma power supply is 0 to 10 kHz (the optimum frequency varies depending on the shape and position of the plasma electrode). The claim 2 decomposed CO + O ^2-of in 103 electric field captured in the Figure 1 a O ^2-, device characterized in that it outside the system exhaust. The CO gas remaining in claim 3 is precipitated and fixed with the catalyst 104 in FIG. 1 (Fe, Pt, Ni, or a wire obtained by sputtering C on these metals, or a rare earth metal filter). A device characterized by separation from O2. An apparatus 105 for returning undecomposed CO and 1/2 O 2 to the combustion section in the apparatus of claim 5. Equipment that uses two or more of the above-mentioned claims or all of the claims of the present invention for the purpose of reducing CO2 emissions in the following combustion equipment of 7-1 to 7-6 (hereinafter referred to as “internal combustion engine etc.”).
7-1.Internal combustion engine
7-2. Incinerator
7-3. Fossil fuel fired boiler
7-4. Fossil fuel combustion furnace
7-5. Metal reduction furnace
7-6. Fossil fuel combustion heater

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