CN1268480A

CN1268480A - Low-cost hydrogen-generating technology by using water as raw material and its equipment

Info

Publication number: CN1268480A
Application number: CN 99103250
Authority: CN
Inventors: 黎英豪
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-03-29
Filing date: 1999-03-29
Publication date: 2000-10-04

Abstract

The present invention relates to a technology and its equipment for producing hydrogen with low cost, and it is suitable for use on motor vehicle, train, steamship and airplane engine, the discharged effluent after burning is pollution less steam so that it is an ideal clean energy source. Its characteristics are: (1) use the reaction between reacting agent and steam to produce hydrogen, (2) the reacting agent can be automatically recovered and cyclically used, the reacting agent is natural gas which is low in cost, (3) reaction takes place below 300 deg.C, the side reaction is exothermic reaction, and so low in power consumption. Main technical indexes are (1) 1.1 kg. water produces 12.4 cu.m hydrogen, (2) power consumption is 1 kwh per cu.m hydrogen produced.

Description

Low-cost hydrogen-producing technology and apparatus by using water

The air pollution source of a large city is motor vehicle exhaust, 6-10 million vehicles exist in the world, about 200 g of lead discharged from the exhaust every year by each vehicle, about 120 tons of lead are discharged every year by 6 million vehicles, and a large amount of lead-containing waste gas enables residents to have a reduced hematopoietic function and is accompanied with cardiovascular diseases, cerebral hemorrhage, chronic nephritis and the like, so that the serious phenomenon causes high importance of medical experts in various countries, the pollution of automobile exhaust is treated, although the existing automobile is provided with an exhaust purifier, the use effect is not good, and the problem is not solved fundamentally. The 21 st century automobiles will use hydrogen fuel to replace the increasingly scarce petroleum. The combustion heat value (energy supply) of hydrogen is extremely high, and the combustion emission is pollution-free steam, so that the hydrogen-containing fuel is an ideal clean energy source.

In the past, the hydrogen production by using a water electrolysis method has high power consumption, while the hydrogen production by using a chemical method has expensive chemical agent materials and high cost. Is difficult to popularize and apply.

The invention relates to a new method for producing hydrogen by using water at low cost, which is not an electrolysis method.

The method has low power consumption and cost and is convenient to popularize and apply.

The main working principle of the invention is as follows: (1) the special reactant (gas) is first treated by plasma technology into plasma state and then treated by plasma treatmentReacting with water vapor, (2) separating hydrogen from reaction products (gas) by using a special molecular sieve, and (3) conveying the rest part after separation to a regenerator to regenerate a reactant which can be repeatedly used. The main technical indexes are as follows: (1) 12.4 meters of hydrogen per kilogram of aquatic product³(2) Hydrogen production per meter³The electricity consumption is 0.1 degree, and the total cost of hydrogen production per meter is 0.5 yuan. (3) The hydrogen yield is 600-60000 m³Hour, or larger, can be applied to thermal power plants.

Fig. 1 is a general view of a hydrogen production apparatus, fig. 2 is a structure of a reaction furnace, fig. 3 is a microwave plasma generator, and fig. 4 is a reactant regenerator.

The invention consists of a reaction furnace 3, a hydrogen-introducing molecular sieve 7, a driving fan 2, a reactant regenerator 9, a microwave plasma generator 12 and the like (see figure 1).

The reactant is natural gas, which is natural air containing N₂80％，O ₂20% of an inexhaustible and inexpensive material, air (n)₂+O₂) Enters from the air inlet 1, flows forward under the drive of the drive fan 2, and passes through a high-frequency microwave electric field generated by a microwave generator 12 to enable N to flow₂And O₂The mixture is in a plasma state, and rapidly reacts in a reaction furnace at 300 ℃ to generate NO: NO is the reactant, a catalyst molybdenum silicide 10 (with the size phi 10 multiplied by 40) is arranged on a reaction screen 11 as shown in figure 2, fine mist water vapor is sprayed through a steam spraying pipe 4 (a plurality of pipes), the catalyst also has the function at the temperature of 300 ℃, and NO reacts with the water (vapor): - - - - (1) due to the small diameter of hydrogen molecule and NO₂The molecular diameter is large, hydrogen is separated by sieving a special hydrogen-introducing molecular sieve 7, the hydrogen passes through the molecular sieve 7 and is output from an outlet 6, and NO remained after separation₂Enters the reactant again under the action of the driving

fan 2The generator

9 and 9 is divided into three grids, each grid is filled with water as

absorption liquid

8, 25 is a main water inlet pipe, 26 is a water inlet branch pipe of each grid, 27 is a branch pipe switch, 29 is a liquid drainage main pipe, and 30 is a liquid drainage branch pipe. The reactant regenerator 9 is also called an absorber, in which NO is present₂Absorbed by water and reacted to produce nitric acid: 32.5 Kcal fever- (2).

The reaction (1) is a main reaction, the reaction (2) is a side reaction, and is an exothermic reaction,which is favorable for reducing the hydrogen production power consumption and generating a reactant NO, namely the reactant NO is regenerated and sent back to the reaction furnace 3 through the branch pipe 28 for reuse, and the insufficient part is still supplemented by the air inlet 1. The side reaction (2) is an exothermic reaction, and the temperature of the returned NO is about 90 ℃, which is favorable for reducing the power consumption of hydrogen production. 24 is NO₂A delivery conduit. The concentration of nitric acid discharged from 29 is low, only about 50%, magnesium nitrate (or concentrated sulfuric acid) can be used as water absorbent, and the dilute nitric acid is concentrated to obtain concentrated nitric acid with concentration greater than 96% as by-product for sale, so that the total cost of hydrogen production can be further reduced.

The hydrogen production reaction furnaces 3 (see figure 2) and 5 are water vapor generators and are sprayed by a spray pipe 4Steam is introduced, 14 is a water adding pipe, and 13 is a water mark. 15 is a generated gas (H)₂+NO₂) The outlet 16 is a reaction tube (ceramic), the power of the electric heating resistance wire (phi 4NiCr wire) 17 is 3-5 kilowatts, the automatic temperature control is constant at 300 ℃, and the temperature 18 is a heat-insulating material.

The microwave generator 12 (see fig. 1 and 3) and 19 are reaction furnace shells, the microwave generator is composed of a magnetron 21, power supply transformers and other elements 20, a waveguide cavity 22 and the like, gas in the gas inlet pipe 1 is completely isolated from electrical elements, and microwaves are emitted into the gas inlet pipe, so that the shells of the gas inlet pipe are replaced by a non-metal plate (high-temperature-resistant plastic or asbestos plate) 23 (see fig. 3) at the turning position of the gas inlet pipe. The microwave power lines are reflected multiple times within the waveguide and launched into the air intake tube through the plastic plate 23.

When N is in the air₂And O₂When passing through the microwave electric field, the free electrons of the gas are paid by the microwave high-frequency energy, the free electrons rapidly accelerate and obtain enough energy, and the atoms of the gas are ionizedThe gas is broken down by the microwave electric field and ionized into a plasma. Plasma is the fourth state of matter in which the following reaction is accomplished very quickly: the reaction temperature is 200-300 ℃,

when the equipment is started, the air inlet pipe 1 increases the air inlet amount to generate enough NO, and after the equipment runs, the reactant regenerator feeds back part of NO for use, and at the moment, only one set of magnetron needs to be started and the air inlet amount needs to be reduced, which is beneficial to reducing the power consumption of hydrogen production. (the power of the magnetron is 2-4 kilowatts).

Claims

1. The low-cost hydrogen-producing technology and equipment by using water mainly include microwave generator, reaction furnace, hydrogen-introducing molecular sieve and reactant regenerator, and are characterized by that: the microwave generator is composed of a magnetron 21, a waveguide 22 and the like, and a microwave electric field is formed at an air inlet.

2. The low-cost hydrogen production technology and device from water according to claim 1 are characterized in that: by N in air₂And O₂As the reactant component, NO is generated under the microwave electric field as the reactant,

3. a low cost hydrogen production technology and apparatus from water as claimed in claim 2, wherein: in the reaction furnace 3, NO reacts with water vapor to generate H₂And NO₂The catalyst is molybdenum silicide,

4. the low-cost hydrogen production technology and device from water according to claim 1 and 2, characterized in that:

outputting hydrogen products through a hydrogen-passing molecular sieve 7 and an outlet 6,

5. the low-cost technology and device for producing hydrogen from water according to claims 1, 2 and 3, is characterized in that:

in the reactant regenerator 9, NO₂Dissolving in water to generate nitric acid and NO, and returning the regenerated NO back to the reaction furnace for reuse, wherein the nitric acid is a byproduct.