Monotube Javelin

[fredrosse]

What part of California is the concern you're consulting for located? Make it out that way much?
Power plant is on the southern shore of the Salton Sea. There are already about 35 Geothermal Power Plants around this area. This new plant will be connected to a Lithium recovery plant, which will produce around 40,000 tons of Lithium product per year. I have been to a few meetings at Palm Springs over the past 2 years.

The Monotube generator should produce about 300 PPH (Pounds pre Hour) steam flow without exceeding maximum ratings. That translates to about 10 horsepower boiler rating according to the old (1876) ASME definitions. For reciprocating steam engines, in 1876, that was the typical steam engine performance, with 70 psig steam pressure and atmospheric exhaust pressure. Modern steam engines can achieve better performance, for example the WWII USA Liberty Ships (2700 built) with triple expansion engines used about 17 PPH per output horsepower. The WWII USA Aircraft Carriers (55 built) with Skinner Compound Uniflow Engines used about 12 PPH per output horsepower.

I am hoping to use about 20 PPH per horsepower in my boat power plant.

Beyond that, my monotube steam generator has a maximum rated heat flux of about 11,000 BTU per square ft heating surface, and in boiler furnaces the heat flux can have maximum values that are several times this value. Therefore, if efficiency of the boiler can be sacrificed with the objective of maximum output, considerably more than 300 PPH would be available.

[TahoeSteam]

Hi Fred, how have you been? Just checking if you have unburdened yourself from the consultation work and have continued onward and upward with your fast launch project?

[fredrosse]

Just got back yesterday from Texas, inspection of progress on the steam separator, 150 inch inside diameter, 75 feet long, 3 inch wall thickness. To me it looked like a small submarine hull. Vessel is lined (weld overlay) with Inconel 625 alloy, thats why it costs about 7x the cost of the same vessel in carbon steel.

[TahoeSteam]

Wow. That sounds incredible. Why inconel? Corrosion resistance, but is there something specific about that plant or just cubic dollars and longevity in mind?

[barts]

Geothermal water/steam is quite corrosive; here's an article on it:

https://www.mdpi.com/2076-3417/13/20/11549

From the article:

Among CRAs, stainless steels (SS) are the most cost-effective, with the 316L grade being widely employed in geothermal heat exchangers [75]. However, 316L SS is not suitable for applications combining high-temperature and H2S-containing environments [76]. The protective Cr-rich passive film destabilizes as the temperature increases from 30 °C to 130 °C. This destabilization was attributed to the replacement of the Cr-oxide film with a less protective Ni-rich film combined with the preferential adsorption of S instead of O at higher temperatures. In contrast, Inconel 625, a corrosion-resistant nickel-based alloy, is recommended for use in sulfur-rich, higher-temperature environments [77].

- Bart

[TahoeSteam]

Thank you for that Bart. I had forgotten one was a geothermal plant.