Discussion on Feasibility of Hydrogen Supply for Hydrogen Bottles
Power construction. Feasibility of hydrogen supply for generators using hydrogen bottles Yao Zhongan (Shanghai Waigaoqiao Power Generation Co., Ltd., Shanghai 2 (1) 137) has obtained the certificate and the quality meets the requirements, which provides a prerequisite for the use of bottled hydrogen to supply hydrogen to the generator. The minimum cost of producing 1m3 of hydrogen from electrolyzed water is 415 yuan; the hydrogen of 1m3 bottle is 2.92~3.05 yuan, so it is very economical to supply hydrogen to the generator with bottled hydrogen. From the actual use of Shanghai Waigao Power Generation Co., Ltd., as long as a small amount of safety equipment is added, a safe and reliable hydrogen supply busbar device can be used to ensure the safety of hydrogen supply from the bottled hydrogen to the generator. Therefore, the purchase of bottled hydrogen to supply hydrogen to the generator is also a viable way to ensure hydrogen supply conditions. Our factory is the first domestic domestic power plant to purchase hydrogen from the bottle to supply hydrogen to the generator. The hydrogen used at present is a by-product of the production of chemical fertilizer by a large chemical fertilizer plant in Shanghai. The purity and humidity of hydrogen have been verified to be related to the power industry. Standard; the hydrogen pressure in the cylinder meets the requirements of Article 6.3 of the standard industrial hydrogen GB/T363495. After several years of operation, it has achieved better economic and security benefits. The following is a discussion of the cost comparison between hydrogen production and the purchase of bottled hydrogen, the piping arrangement for hydrogen supply with hydrogen bottles, and the measures to be taken for safe fire protection. 1 Comparison of the cost of hydrogen production and the purchase of bottled hydrogen 1. The electricity consumption of hydrogen produced by electrolyzed water According to Faraday's law of electrolysis, the theoretical amount of 1 m3 of hydrogen and 0.5 m3 of oxygen produced by electrolyzed water is 2.94 kWl. Sex bubbles cause the conductivity of the solution to decrease, resulting in an increase in the cell voltage. In addition, the cell voltage is increased due to hydrogen overpotential, oxygen overpotential, gas covering the surface of the electrode, and the like. The standard water electrolysis hydrogen production equipment B/T590396 stipulates that the hydrogen production equipment produces the direct current consumption of hydrogen per unit (1 m3 of hydrogen, the electric energy consumed by the electrolyzer) is calculated according to formula (1): DC working current of the electrolyzer, A; V electrolysis Tank DC operating voltage, V; hydrogen production during Qh2 test, m3/h; test time. In the commissioning and trial operation stage of the electrolyzed water hydrogen production unit of our factory, the power consumption of hydrogen produced by electrolyzed water was tested and calculated according to the formula (1). The specific test results are as follows. In the first and second tests, the DC working voltage is 68, V, DC working current is 740A, continuous operation for 4h, and the hydrogen production is 30.5831.97m3 respectively. Substituting (1) for Wh2 if in the process of electrolyzing water Considering the efficiency of the rectifying device, the electric loss of the rectifying device to the electrolytic cell, the control power source of the hydrogen generating device, the power consumption of the circulating pump, and the water pump, the actual power consumption of the hydrogen produced by the electrolyzed water is larger than the above calculated value. At the same time as the above two tests, the power consumption of hydrogen production by electrolysis of water by alternating current was also measured. If the power consumption of hydrogen produced by electrolyzed water is calculated by AC voltage and AC current, it can be calculated by formula (2): AC working current, A; V-AC working voltage, V 2 times test. The AC voltage of the first and second tests is 370V AC current is 101,102A, continuous operation for 4h, and the hydrogen production is 30.5831.97m3 respectively. The AC power consumption of hydrogen production equipment can be substituted into (2) Calculated Wih2: the first test is 8.466kW-h/m3; the second test is 8. In order to meet the power industry standards and generator requirements, after the hydrogen is produced in the electrolyzed water, the adsorption dryer must also be used. To reduce the humidity of hydrogen. The adsorption dryer consumes about 50 kW.h per day. If it is calculated according to the daily production of 192 m3 of hydrogen, the cost of water consumption when converting to 1 m3 of hydrogen and 1.2 hydrogen production is calculated by the above calculation. The actual electricity consumption of 1 m3 of hydrogen should be electrolyzed water. Hydrogen consumption, dry hydrogen power consumption, and other power consumption, totaling 8.440~8.726kWh. If the 1kWh power is calculated at 0.3 yuan, the electricity fee for each 1m3 hydrogen is 2.53. The hydrogen production unit needs 4m3/h of cooling water. Due to the change of temperature and water temperature in different seasons, the cooling water consumption of the hydrogen production unit is 2.63. The cooling water consumption of the drying unit is 1.00~1.70m3/h, and the total cooling water consumption is 3.63~ 5.70m3/h. If the hydrogen production is 7.65~8.00m3/h, the water consumption from the conversion to 1m3 hydrogen is 0.47 ~ 0.71m3. For example, 1m3 cooling water, that is, 1t water is calculated at the price of 1.5 yuan, and the preparation of 1m3 hydrogen is required. Water cost 0.70 1.3 Total cost of hydrogen production According to the above calculation, 1m3 of hydrogen, the oldest fee for water and electricity, the operation and maintenance cost of hydrogen production and drying equipment, spare parts and accessories, condensate fee, chemical fee, etc. The total cost of producing 1m3 of hydrogen is at least 4.15 yuan. 1.4 The total cost of buying hydrogen from the fertilizer plant to buy bottled hydrogen, the price is 11. 20 yuan / bottle, the volume of each cylinder is 40 ~ 42L. The volume of hydrogen in each cylinder can be calculated according to formula (3): C When the volume of hydrogen, K converts the current pressure and temperature into standard atmospheric pressure, the coefficient of hydrogen volume calculated at 20 ° C state; hydrogen cylinder volume, m3. Calculate the volume of hydrogen in the cylinder from 5.0 to 5.3 m3 When the price of hydrogen in the cylinder is 2.11, 5 hydrogen cylinders are installed in each car, and 20 hydrogen bottles are installed in each container. The freight rate is 4 (1) yuan/car. 80 yuan Therefore, the cost of buying bottled hydrogen is hydrogen ex-factory price plus freight, that is, 2.11 ~ 3.04 yuan for 1m3 hydrogen. The maintenance cost of the hydrogen bottle and the assembly grid is very low. The hydrogen cylinder valve and the copper tube are replaced once every three years (each valve is only 28 yuan, the copper tube is used in a small amount, and the cost is very low). According to the regulations of the pressure gas bottle, the hydrogen bottle needs to be inspected regularly. The total cost of the above two items is about 1,800 yuan. The annual maintenance cost of each hydrogen bottle assembly is 600 yuan. The above maintenance and inspection costs are reduced to less than 0.01 yuan for buying 1m3 bottle of hydrogen. The total cost of buying bottled hydrogen for 1m3 is 2.92. 2 The pipeline for hydrogen supply from hydrogen bottle is configured to ensure the safety of the unit during maintenance. Our factory uses hydrogen for unit system and one hydrogen supply for hydrogen for one unit. The hydrogen bottle hydrogen supply line is very simple and easy to operate. 2.1 The current hydrogen supply pipeline configuration has been confirmed by cost accounting to obtain better economic benefits when purchasing bottled hydrogen. The pipeline as shown is configured as a hydrogen storage tank or hydrogen in the case where the hydrogen production unit and the hydrogen storage tank have not been removed. A bus that supplies hydrogen to the generator. When the hydrogen in the hydrogen storage tank is used to supply the generator, the total valve is opened, and the hydrogen gas with a pressure of 0.5 MPa can be sent to the generator through the pressure reducer and the isolation door of the hydrogen supply mother tube; when the hydrogen bottle is used for hydrogen supply, Strictly store the hydrogen supply main valve of the hydrogen tank, and add the blocking plate at the inlet flange of the main pipe isolation door. Install a hydrogen pressure reducer at the outlet valve of the hydrogen bottle assembly and decompress the hydrogen in the hydrogen bottle to 0.5. MPa, hydrogen is supplied to the generator through a hydrogen inlet valve that is sent to the busbar through the hose. The busbar is equipped with a low of about 3-2M兀h up to d67, and 兀ha is included in the equipment fold blish only to monitor the hydrogen supply pressure: there is also a replacement sampling gate t for replacing the hydrogen supply manifold or The hydrogen supply bus is arranged, and the purity of the hydrogen in the hydrogen bottle can be sampled and analyzed. Due to the consideration of the spring-loaded safety valve on the pressure reducer, when the output pressure exceeds 0.6 MPa, the safety valve will automatically open the exhaust, so the safety valve is not installed on the busbar. 2.2 The improved hydrogen supply pipeline configuration has been proved for several years. The use of hydrogen cylinders to supply hydrogen to the generator not only reduces the cost of power generation, but also is safe and reliable. To this end, our factory has deactivated the hydrogen production unit, all purchased bottled hydrogen to supply hydrogen to the generator, and intends to configure the bus bar to make the hydrogen supply bus line simpler. In order to prevent the safety valve on the pressure reducer from failing, a safety door is added to each hydrogen supply bus. In order to facilitate monitoring, an online hydrogen purity meter, a humidity meter and a flow meter can also be added to the bus bar. This hydrogen supply busbar configuration meets the safety and regulatory requirements for hydrogen and hydrogen transport in relevant national and industry standards. 3 Concluding remarks 3.1 If there is a hydrogen source factory that can provide reliable quality and low price in the vicinity of new power plants, hydrogen can be supplied to the generator by purchasing bottled hydrogen, which can save a lot of capital investment and reduce the production cost after production. Hydrogen production personnel. 3.2 For the power plant that has been put into operation, if there is a hydrogen source factory that can provide reliable quality and low price in the vicinity of the power plant, hydrogen can be supplied to the generator by purchasing bottled hydrogen; the original hydrogen production device can be reserved as a standby hydrogen production device. 3.3 For the power plants that have been put into operation, due to the different types of hydrogen production and drying equipment used, equipment conditions, hydrogen production and drying efficiency and operating costs, if it is to be converted to bottled hydrogen to supply hydrogen to the generator, it is recommended to carry out hydrogen production and drying equipment. The efficiency test calculates and compares the cost of hydrogen production with the purchase of bottled hydrogen. 3.4 If hydrogen is supplied to the generator using bottled hydrogen, it is more safe. There are special requirements for the storage, transportation, use, regular inspection and hydrogen supply of hydrogen bottles. The training of hydrogen supply personnel should be strengthened, and a strict management system should be established to ensure the safety of hydrogen supply using hydrogen bottles. (Editor: Wang Pingzhi) Cpe Frosted Zipper Bag,Customized Cpe Plastic Bags,Cpe Frosted Self-Adhesive Bags,Frosted Zipper Bag Dongguan Pasike Packaging Co., Ltd. , https://www.dgpasike.com