JPH06241132A - Hydrogen addition system and method for operating same - Google Patents

Abstract

PURPOSE:To provide a hydrogen addition system for an internal combustion engine and a method for operating the same, where methanol fuel is supplied to a reforming unit under pressure as low as feed liquid path resistance required for supplying the fuel from a tank to a carburetor. CONSTITUTION:In a hydrogen addition system for an internal combustion engine for supplying fuel staying in a methanol tank 11 and a water tank 12 to a reforming unit by pumps 13, 14, the reforming unit is constituted of a carburetor 19 and a reformer 15 which are independent of each other. A stop valve 24 is disposed on a path of reforming gas to be supplied from the reformer 15. Another stop valve 23 is provided on a path of methanol fuel to be supplied to the carburetor 19 by the pumps 13, 14. A controller 22 controls to open or close the stop valves 23, 24 and start the pumps 13, 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogenation system for an internal combustion engine which reforms methanol fuel into hydrogen gas by using exhaust gas of the internal combustion engine as a heat source, by supplying methanol fuel by a pump, vaporizing and reforming it. And a method for operating the same.

[0002]

2. Description of the Related Art Hydrogen gas has about three times as much reaction energy per mass as gasoline, and its calorific value is about 2.7 times as much as that of gasoline. Therefore, it is expected as a fuel for automobile engines. There is. By the way, when a fuel obtained by adding about several percent of hydrogen gas to gasoline is used in an engine of an automobile that uses gasoline as a fuel, the engine has an effect of a wide flammable range of hydrogen gas and an ignition speed. The operating conditions of can be set to lean combustion and high compression side, and as a result, it is possible to improve the fuel efficiency, and as a study to add hydrogen gas to such gasoline, as a research to add exhaust gas from the engine A study has already been reported in which methanol is reformed by exhaust heat in a reformer, and the reformed gas mainly containing the obtained hydrogen gas is supplied to an engine (for example, the Japan Society of Mechanical Engineers, Vol. 52, No. 484,
(Showa 61-12, 4084-4096).

[0003]

FIG. 2 is a schematic diagram showing that the exhaust heat of exhaust gas discharged from an internal combustion engine is used to reform methanol and the generated hydrogen gas is added to the internal combustion engine. 1 shows a contemplated internal combustion engine hydrogenation system. 1 is a methanol tank, 2 is a water tank, 3 is a pump for sucking methanol from the methanol tank 1 and supplying it to the reformer 5, 4 is sucking water from the water tank 2 and supplying it to the reformer 5. It is a pump for. Reference numeral 5 is a reformer for reforming methanol to generate a reformed gas mainly containing hydrogen gas, and a reforming catalyst is provided inside the reformer 5 by coating or filling. Reference numeral 6 is a surge tank for storing reformed gas, and 7 is an internal combustion engine having two fuel systems capable of utilizing gasoline and reformed gas as fuel, that is, a reformed fuel system and a gasoline system. In this internal combustion engine hydrogenation system, the reformer 5 is configured by integrating the reforming section and the vaporization section.

In this internal combustion engine hydrogenation system,
Pump 3 from the methanol tank 1 and the water tank 2,
It is supplied to the vaporization section in the reformer 5 by the unit 4. The fuel vaporized in the vaporization section enters the reforming section, is mainly reformed into hydrogen gas, is stored in the surge tank 6, and supplies a necessary amount to the internal combustion engine 7 through the valve 9. Fuel is burned in the internal combustion engine 7, and the generated exhaust gas has heat. Therefore, the exhaust gas is introduced into the reformer 5 and used as a heat source for reforming. The exhaust gas discharged from the reformer 5 is further cooled by the condenser 8, the condensed water is collected in the water tank 2, and the exhaust gas is discharged outside the system.

However, in general, the pressure of the vaporized fuel system in the reformer is advantageous for the reforming reaction because the probability of contact between the reforming catalyst and the fuel gas is increased by increasing the density (pressure) of the fuel gas. Becomes Therefore, in the internal combustion engine hydrogenation system, in order to efficiently supply the fuel, it is necessary to increase the contact probability between the reforming catalyst and the fuel gas. In addition, it is necessary to cool and store hydrogen in a surge tank in order to increase the density of the reformed gas that is diluted at high temperature.

In order to supply the fuel for such a purpose, it is necessary to raise the gas pressure (density) in the entire reformer in the supply system. Therefore, the pump that supplies the fuel needs a discharge pressure to withstand these pressures, and the power required for the discharge pressure is considerable. Therefore, in order to secure the pressure necessary for the pump, it is unavoidable that the cost is increased and the size is increased.

Therefore, the present invention provides a hydrogen addition system for an internal combustion engine and a method of operating the same, which can supply methanol fuel to a reformer at a low pressure of about the resistance of a liquid supply line. To aim.

[0008]

In order to solve the above problems, the present invention provides a fuel tank, a pump for supplying fuel from the fuel tank to a reformer, and a methanol fuel for supplying hydrogen gas. In a hydrogen addition system for an internal combustion engine having a reformer that mainly reforms a reformed gas, the reformer includes a vaporization section and a reforming section, each of which is configured as a separate body and supplied from the reforming section. A stop valve is provided in the reformed gas pipeline, a stop valve is provided in the methanol fuel pipeline between the pump and the vaporization section, and each stop valve is provided in accordance with the pressure in the vaporization section. A hydrogen addition system for an internal combustion engine, comprising a controller for instructing opening and closing of the pump and starting of the pump.

The present invention is also an internal combustion engine having a tank for storing fuel, a pump for supplying the fuel from the tank to the reformer, and a reformer in which a vaporizing section and a reforming section are separate bodies. A hydrogen addition system using an engine hydrogen addition system, characterized in that the supply pressure of the methanol fuel from the fuel tank to the vaporization section by the pump is controlled so as to be a low pressure of about the resistance of the liquid transfer conduit. Is the driving method.

[0010]

According to the present invention, the reformer for alcohol fuel is composed of a vaporizing section and a reforming section, each of which is provided as a separate body, and the valve is controlled so that the discharge pressure of the pump is supplied from the tank to the vaporizing section. The discharge pressure may be as high as the resistance of the liquid-feeding pipe until that time, and low-load operation can be performed.

[0011]

Embodiment 1 FIG. 1 is a diagram of a hydrogen addition system of an internal combustion engine according to the present invention, in which methanol is reformed by utilizing exhaust heat of exhaust gas discharged from the internal combustion engine, and a reformed mainly hydrogen gas produced. 1 shows an internal combustion engine hydrogen addition system in which fuel supply is performed by valve control when a high-quality gas is added to an internal combustion engine.

Reference numeral 11 is a methanol tank, 12 is a water tank, 13 is a pump that sucks methanol from the methanol tank 11 and supplies it to the vaporization section 19, and 14 is a water tank 1.
It is a pump for sucking water from 2 and supplying it to the vaporizing part 19. A heat exchanger for exchanging exhaust heat of exhaust gas from the internal combustion engine 17 with methanol fuel is arranged in the vaporization unit 19. Reference numeral 15 is a reforming unit for reforming the vaporized methanol fuel from the vaporization unit 19, and the vaporization unit 1
9 is separated and configured separately, and a vaporizer 19 and a reformer 15 constitute a reformer. A reforming catalyst is provided inside the reforming section 15 by coating or filling. Reference numeral 16 is a surge tank that stores the hydrogen gas generated in the reforming unit 15, and 17 is an internal combustion engine to which fuel from the gasoline system and the hydrogen gas system is supplied.

In the hydrogen addition system for an internal combustion engine of the present invention, the reformer for reforming methanol fuel as described above is composed of the vaporizing section 19 and the reforming section 15 which are separate bodies. Furthermore, in the internal combustion engine hydrogenation system of the present invention, a sensor system for controlling fuel supply, a supply system,
A control device including a control system is provided. That is, the sensor system is provided with a pressure sensor 20 that detects the pressure in the vaporization section 19 and a pressure sensor 21 that detects the pressure in the surge tank 16.

Regarding the supply system, the methanol tank 11
And a stop valve 23 for opening and closing the supply of fuel from the water tank 12, a stop valve 24 for opening and closing the supply of reformed gas from the reforming section 15, and a opening and closing of the supply of reformed gas from the surge tank 16. A stop valve 25 is provided. Regarding the control system, a controller 22 that outputs appropriate commands for turning on / off the pumps 13 and 14 and turning on / off the stop valves 23, 24, 25 by taking in pressure from the pressure sensors 20 and 21. Is. In addition, according to a command from the controller 22, the pumps 13, 1 are appropriately timed.
Relays 26 and 27 for turning ON / OFF the No. 4 are provided.

Next, the operation of the internal combustion engine hydrogenation system of the present invention will be described. The pump 13 and the pump 14 are operated, the stop valve 23 is opened, and the stop valve 24 is closed, so that the methanol tank 11 and the water tank 1
The methanol fuel is supplied from 2 to the vaporization section 19. The pump 13 and the pump 14 are intermittently operated and controlled by the relay 26 and the relay 27 which have received a command from the controller 22, and when the liquid is fed for a certain time, the pump 13 and the pump 14 are stopped for a certain time.
The pump 13 and the pump 14 that are intermittently operated in the vaporization unit 19
It has a volume larger than the volume of fluid that can be delivered from a certain time.

Next, by stopping the operation of the pumps 13 and 14 and closing the stop valves 23 and 24, the liquid is sent to the vaporizing section 19 by one intermittent operation of the pumps 13 and 14. While the fuel is vaporized by heat exchange with the exhaust gas, the pressure inside the vaporization section 19 rises, but the pressure does not propagate to the pump 13 and the pump 14.

The fuel gas vaporized in the vaporizing section 19 is introduced into the reforming section 15, where it is reformed under high temperature and high pressure into a reformed gas mainly composed of hydrogen gas. When the pressure in the vaporization section 19 reaches the set pressure, and the relationship between the pressure in the reforming section 15 and the pressure in the surge tank 16 is (reforming section pressure)>
When the (surge tank pressure) is controlled by the controller 22, the pump 13 and the pump 14 are stopped, the stop valve 23 is closed and the stop valve 24 is opened, so that the reforming section 15 reforms. The reformed gas is caused to flow into the surge tank 16 in a low temperature / high pressure state where heat is exchanged with the outside air.

Next, when the pressure in the surge tank 16 reaches the set pressure, the stop valve 25 is opened and the reformed gas mainly containing hydrogen gas is introduced into the internal combustion engine 17.

[0019]

According to the present invention, the reforming device is composed of a separate device comprising a vaporizing part and a reforming part, and a stop valve provided upstream of the vaporizing part and downstream of the reforming part is a controller. Since the valve is controlled by the valve and the pump is intermittently controlled and operated, the discharge pressure of the fuel by the pump may be as low as the resistance of the liquid transfer pipe line until the fuel is supplied from the tank to the vaporization section. The hydrogenation system can operate at low load.

[Brief description of drawings]

FIG. 1 shows an internal combustion engine hydrogenation system using a methanol reformer of the present invention.

FIG. 2 is a currently considered internal combustion engine hydrogenation system characterized by reforming methanol by utilizing exhaust heat of exhaust gas discharged from the internal combustion engine and adding the produced hydrogen gas to the internal combustion engine. Indicates.

[Explanation of symbols]

 11 Methanol Tank 12 Water Tank 13,14 Pump 15 Reforming Section 16 Surge Tank 17 Internal Combustion Engine 18 Condenser 19 Vaporizing Section 20,21 Pressure Sensor 22 Controller 23,24,25 Stop Valve 26,27 Relay

Claims (2)

[Claims] 1. An internal combustion engine having a fuel tank, a pump for feeding fuel from the fuel tank to a reformer, and a reformer for reforming methanol fuel into reformed gas mainly containing hydrogen gas. (1) The reformer comprises a vaporization section and a reforming section, each of which is configured as a separate body, and (2) a stop valve in a pipeline of the reformed gas supplied from the reforming section. (3) A stop valve is provided in the methanol fuel pipe between the pump and the vaporization section, (4) Opening / closing of each of the stop valves according to the pressure in the vaporization section, and A hydrogen addition system for an internal combustion engine, comprising: a controller for instructing start of a pump. 2. (1) An internal combustion engine having a tank for storing fuel, a pump for supplying fuel from the tank to a reformer, and a reformer in which a vaporization section and a reforming section are separate bodies. (2) An intermittent operation control is performed so that the supply pressure of the methanol fuel from the fuel tank to the vaporization section by the pump is a low pressure of about the resistance of the liquid transfer conduit. Operating method of hydrogen addition system.