Liquid nitrogen vaporization device
Thread Content
1. Requirements: Nitrogen demand of 2400 Nm3/h, pressure of 1.0 MPa(g); intermittent use. 2. Proposal: 2 liquid nitrogen storage tanks with a capacity of 15 m3 each (at 1.6 MPa), 2 air-cooled vaporizers (1500 Nm3/h per unit), 1 electrically heated vaporizer (to be used when temperatures are too low in winter, specifications yet to be determined), and a pressure reduction device. Experts, is this proposal reasonable? Is the amount of the vaporizer sufficient? If high performance is required from the control system, what would be the total investment for this entire setup, including not only the civil engineering costs but also all the piping, valves, and PLC controls? By the way, the factory is located by the sea in Dalian
Theoretically, two air-cooled vaporizers should be sufficient. For electrically heated vaporizers in winter, a model with a capacity of 600–1000 should work fine; the price is not known
The nitrogen demand is 2400 Nm3/h; therefore, at least two air-cooled gasifiers with a capacity of 2400 Nm3/h each should be used, one in operation and the other as a backup, to ensure continuous gas supply. If the temperature of the gas produced isn’t sufficient in winter, an electric heating regenerator can be added to maintain continuous operation
Reply to 3# prt0683: Are carburetors prone to breaking? Why choose two? Intermittent operation doesn’t require a backup machine, right?
Reply to 2# SuperFree2316: 600~1000 refers to the amount of vaporization, right?； What should the power be approximately?
Regarding the question raised by the poster, it is best to have a professional manufacturer – there are many such companies available online – prepare a technical plan for you; this approach is both reasonable and meets the production requirements. It is not necessary to use a combination of an air-temperature vaporizer and an electrically heated vaporizer; you can opt for a water-bath vaporizer or one that uses steam heating (if your facility has steam available). The volume of vaporizers that use water bath or steam heating is smaller than that of air-cooled ones, and no electricity is required
Reply to 6# Wolf from the Northwest: First of all, thank you very much! This plan was developed in consultation with the manufacturer, but since nothing similar has been done before, I’m not sure about it, so I’d like to hear more opinions from other users
This post was last edited by prt0683 on 2011-5-20 at 13:01. Reply to 6# Northwest Wolf: What you say makes sense; I agree with your view! But a steam boiler is needed
The manufacturer said that steam-heated vaporizers are an old-fashioned approach, listing many disadvantages, and claiming that air-based systems are better； May I ask: Is a steam-heated vaporizer an old-fashioned approach? Has it been phased out now?
Energy conservation is being promoted these days, and it would be better if steam isn’t used. The advantages and disadvantages of a particular solution need to be considered from various aspects. If your organization has excess steam and there is limited space for liquid nitrogen vaporization devices, then a steam-based vaporizer could be an option. If no steam is available, a water-bath vaporizer can be used. Given that Dalian experiences very cold winters, a hot-water circulation or electrically heated vaporizer could be suitable. These types of vaporizers are simple in design; they can be used when temperatures are extremely low in winter, offer flexible operation, but have high energy consumption
In air-temperature vaporizers, frosting tends to form on their surfaces after long periods of continuous operation, and this issue is difficult to address. Therefore, it is recommended to use two air-temperature vaporizers as a backup; in that case, there is no need for an electric heater. A liquid nitrogen storage tank with a capacity of 15 cubic meters and a pressure of 1.6 MPa costs around 240,000 yuan. An air-temperature vaporizer with a capacity of 240 standard cubic meters per hour costs about 100,000 yuan. When including the pressure reduction equipment, valves, pipes, and electrical control systems, the total cost comes to around 800,000 yuan.