I did it! I made a highly efficient automated furnace

[ждун]

Just wanted to share my excitement of building my own automated furnace setup. This was a project that I was working on for more than a year and got stuck with it multiple times. I know there are plenty of setups with scripts available in the workshop and on youtube, but they are mostly similar, I had something different in mind. I wanted to make a furnace that is highly efficient, meaning its using as little fuel as possible. To achieve that, it is mostly reusing its own exhaust gas. Often it doesn't even require to use any fuel, if it can reach proper parameters using its previously stored exhaust alone.

Now how it works:
At first there is a gas preparation unit which consists of three isolated tanks. Heat tank, waste tank, coolant tank. Oxygen and Hydrogen are being injected into heat tank where it burns maintaining 40 mpa and 2150 °C. The coolant tank is simply filled from the mars atmosphere with an active vent up to 40 mpa. This was the simplest solution for mars, but other gas that is cooler than 200 °C will work as coolant. In an alternative version for moon, some of the waste tank content is being passed to coolant tank where it is passively cooled with radiators under 200 °C. The waste tank is filled from the furnace exhaust up to 40 mpa, the overhead is being exhausted or can be further processed as heating gas. However this setup does not produce a lot of exhaust. The temperature in the waste tank will variate depending on which alloys are being crafted. If I make alloys that require higher temperatures, the waste will be hotter.

Next, the furnace itself. Its both input and output are joined in a single manifold behind the furnace. This is where the magic happens. The furnace itself is not controlled, both its input and output valves are always open at 100% at all times. All temperature and pressure controlling is happening in the manifold pipe behind the furnace. There are four standard volume pipes involved in the process. One injects hot gas (~2150°C) from the heat tank. One injects coolant (<200°C) and two pumps are injecting and removing waste gas. It turned out that it has a number of advantages not to use furnace own input and output valves, but instead prepare gas outside of the furnace to proper parameters. This makes the whole setup a lot simpler.

To achieve proper temperature and pressure two PID controllers are used. One for pressure and one for temperature control. The pressure controller is fairly simple, it will close the output valve until certain pressure is reached, and then will control the output in a way that it hold that pressure. The temperature controller is a bit more complex as it controls three other pumps (heat in, waste in, coolant in) in a smart way, so that it tries to use mostly gas from waste tank, and add only as little from the heat tank or coolant tank as needed to achieve proper temperature in the manifold pipe. My tests were showing that its using more than 90% own waste gas, and only about 10% is added either from heat or coolant tank depending on if the requested temperature is higher or lower than content of waste tank. This was result of longer test run where i was making tons of all kind of alloys but mostly steel.

Additionally I have one more controller for selecting recipe. This is also my own special implementation. It holds the complete data for all alloys. For each of the 18 alloys it stores its Hash, Max Temp, Min Temp, Min Pressure, Max Pressure. For example it can be asked to return Min Temperature for Astralloy. Or Max Pressure for Inconel etc... The pressure and temperature controllers are querying the data stored in the recipe controller to select proper temperature and pressure setpoints. They do it in a smart way so that the furnace must not change parameters if it doesn't have to. For example if I made say steel first and then wanted to make something else, the temperature controller will take current waste temperature in account and see if it is within the limits of next selected alloy. If it is, it will not change temperature setpoint, pumping heat or coolant in to achieve new setpoints, instead it will try to keep current parameters as much as possible if they are within the limits of selected alloy. This part is not yet completely finished, so I am confident that it should increase efficiency of the setup even more.

So in the end I have 4 IC controllers.
Data Controller (holding data for all alloys and allows to select one to make with a dial)
Gas Unit Controller (preparing heat and coolant gas)
Pressure Controller (controlling the pressure)
Temperature Controller (controlling the temperature)

If anyone is interested in this setup I could share the scripts and explain how to set everything up.

[Ketrix]

Nicely done. The furnace is like the final boss of this game.

[God, owner of the Universe]

Originally posted by Ketrix:

The furnace is like the final boss of this game.

How about rocketry?

[PhoenixKnight314]

That furnace setup sounds awesome!

[Malkuth]

Sounds amazing, I just build a manual system lol every time with a Hot tank.