This article continues to briefly introduce common hydrogen production methods in Chengdu. Let's take a look!

1、 Hydrogen production from industrial by-product

Hydrogen production from industrial by-product is to use industrial tail gas rich in hydrogen as raw material, mainly by pressure swing adsorption (PSA) method, to recover and purify hydrogen. At present, the main sources of tail gas include by-product gas from chlor alkali industry, coke oven gas and by-product gas from light hydrocarbon cracking. Compared with other hydrogen production methods, hydrogen is produced by industrial by-products The major advantage is that there is almost no need for additional capital investment and fossil raw material investment, and the hydrogen obtained has significant advantages in terms of cost and emission reduction. We measured the potential supply of hydrogen produced by industrial by-products, and believed that the theoretical hydrogen production scale was sufficient to meet the market demand of "one million fuel cell vehicles will be on the road by 2030", and it was one of the best hydrogen supply solutions in the early and middle stages of fuel cell development.

2、 Hydrogen production from chlor alkali by-product

Hydrogen production from chlor alkali by-product has the advantages of low purification difficulty, low impurity content and effective utilization of hydrogen. The chlor alkali plant uses salt water as raw material, and uses ion membrane or asbestos membrane electrolyzer to produce caustic soda, chlorine, and by-product hydrogen. Most chlor alkali plants adopt the physical adsorption PSA method to purify the by-product hydrogen, which can obtain high-purity hydrogen. This process has the advantages of low energy consumption, low investment, high automation, high product purity, and no pollution. Considering that the purity of by-product hydrogen is more than 99% before purification, and the main impurities are oxygen, nitrogen and steam, the production cost of high-purity hydrogen under this process is only 1.3-1.5 yuan/Nm ³， Compared with other preparation methods, the advantages of cost and environmental protection are prominent.

In terms of output, the domestic caustic soda output will reach 34.2 million tons in 2018, and the by-product of each ton of caustic soda produced will be 280Nm ³ Hydrogen (25kg) is estimated to produce 855000 tons of hydrogen annually. At present, there are two ways for domestic chlor alkali plants to utilize the by-product hydrogen. One is to react with chlorine to prepare hydrochloric acid or other chemicals, and the other is to burn to release heat energy (large initial investment). At present, more than 30% of the by-product hydrogen is directly vented, resulting in resource waste. If the vented by-product hydrogen is fully utilized, in theory, 255600 tons of high-purity hydrogen can be supplied to the outside world, which can supply more than 1 million fuel cell vehicles, enough to meet the short-term and medium-term hydrogen demand of domestic fuel cell vehicles.

3、 Hydrogen production from coke oven gas

China is a coke producing country. In 2018, the domestic coke output reached 438 million tons, accounting for 60% of the total output. Coke oven gas is a by-product of the coking process. Except for a large amount of hydrogen (more than 50%) and methane, other components are relatively complex and vary greatly with the different raw coal. The pressure swing adsorption hydrogen production process of coke oven gas is divided into five processes: raw material shrinkage, refrigeration purification separation, pressure swing adsorption decarbonizing, desulfurization compression, pressure swing adsorption hydrogen production and deoxidation. The purity of hydrogen produced exceeds 99.99%. The theoretical space for hydrogen production from domestic coke oven gas is large, but the self recycling system of iron and steel combined coking enterprises is usually mature, most of the coking gas has been fully utilized, and the actual hydrogen supply that can be purified and supplied externally is limited.

To begin with, we are limited in space. Ketruixing is mainly engaged in the production and manufacturing of Chengdu hydrogen production units and Chengdu hydrogen purification technology. If you want to know more about this, please call new and old customers for details