An online high-purity hydrogen preparation system for fuel cells and its control method

Abstract

The invention discloses an online high-purity hydrogen preparation system for a fuel cell. The online high-purity hydrogen preparation system comprises a methyl alcohol box as well as a raw material box and a catalytic burner which are connected with the methyl alcohol box through a methyl alcohol metering pump, wherein a fuel cell discharge water inlet is formed in the raw material box, an oxygen inlet is formed in the catalytic burner, an ethanol water metering pump and a heat exchanger are sequentially connected onto the raw material box, a vaporizer is connected onto the heat exchanger, a reforming reactor is connected onto the vaporizer, a palladium film purifier is connected onto the reforming reactor, and the palladium film purifier is connected with the catalytic burner; the invention further discloses a control method of the system. According to the system provided by the invention, online hydrogen supplying is performed through a manner of using a methanol water reforming reaction to produce hydrogen, the yield of pure hydrogen is controlled through adjusting the flow of an ethanol water mixture; the method has the characteristics of high hydrogen storage density, high hydrogen purity, low energy consumption, compact structure, simpleness and convenience in start-stop controlling, easiness in implementing modular design and the like.

Description

technical field [0001] The invention belongs to the technical field of on-line hydrogen production, and relates to an on-line hydrogen production system for a proton exchange membrane fuel cell and a control method thereof. Background technique [0002] A fuel cell is a highly efficient power generation device that does not undergo a combustion process. A fuel cell is different from a battery in the traditional sense. It directly converts the chemical energy stored in fuel and oxidant into electrical energy by electrochemical means. There are many types of fuel cells, which can be divided into alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, proton exchange membrane fuel cells and solid oxide fuel cells according to different electrolytes. Among them, compared with other types of fuel cells, proton exchange membrane fuel cells have the advantages of high power density, high energy conversion efficiency, low vibration and noise, low temperature s...

AI Technical Summary

Problems solved by technology

The advantage of this hydrogen supply method is that the structure of the hydrogen storage device is simple, easy to carry and use, and the hydrogen charging and discharging speed is fast. The disadvantage is that the hydrogen storage density is low. Even if the hydrogen storage pressure is increased to 70MPa, the volume hydrogen storage density is only 4kg / 100L or so

This technology has the characteristics of high safety and good reliability. Its disadvantages are that the hydrogen storage device has a large volume and weight, high manufacturing cost, and low hydrogen storage density.

The main features of this technology are the small volume and weight of the hydrogen production device, high hydrogen storage density, and simple structure. The disadvantage is that the generated H2 contains CO, CO2 and other impurity gases, which need to be further separated and purified before use.

The commonly used purification technology is pressure swing adsorption technology, which can obtain hydrogen with higher purity, but the overall volume and weight of the pressure swing adsorption device is large, the purification efficiency is low, and the power consumption is large, which greatly reduces the overall cost of the fuel cell system. Power generation efficiency, so it is not suitable for matching with fuel cell power generation system

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