In Oxygen Not Included (ONI), chlorine gas offers a highly effective and unique method for sterilizing contaminated water by leveraging its physical properties within an enclosed storage system. This process allows for the complete disinfection of large volumes of water without consuming the chlorine itself or polluting the water supply.
Understanding Water Contamination in ONI
Water in Oxygen Not Included can become contaminated with various types of germs, such as Food Poisoning or Slimelung, which can negatively impact your Duplicants' health. While other methods like the Water Sieve or Desalinator purify water by removing contaminants like dirt or salt, they do not inherently kill germs. This is where chlorine shines as a dedicated sterilization agent.
How to Sterilize Water Using Chlorine Gas
The primary method for using chlorine to purify water involves creating a sealed environment where chlorine gas can interact with the surface of the contaminated water. The key is to exploit chlorine's density; it's heavier than most other gases but lighter than liquids, allowing it to layer perfectly above water.
The Chlorine Disinfection Process
Here's a step-by-step guide to setting up an effective chlorine water sterilization system:
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Build an Enclosed Water Storage:
- Construct a sealed room or tank, typically 2-3 tiles high, with insulated tiles to prevent temperature changes. This chamber will house your germy water and chlorine gas.
- Include a Liquid Vent at the bottom for incoming germy water and outgoing purified water.
- Include a Gas Vent at the top for incoming chlorine and a Gas Pump at the top for removing chlorine.
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Pump in Contaminated Water:
- Direct your germ-laden water (e.g., Polluted Water, Water with Food Poisoning) into the bottom of this enclosed storage chamber via the Liquid Vent. Fill the chamber with the desired amount of water.
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Introduce Chlorine Gas:
- Once the water is in place, pump chlorine gas into the top of the chamber using the Gas Vent. Due to its higher density compared to other gases but lower density than water, the chlorine will settle above the surface of the water, forming a distinct layer. This is crucial for the disinfection process.
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Allow for Disinfection:
- Let the chlorine gas hover above the surface of the water. The chlorine will actively sterilize the water as long as it is in contact. After a full cycle (typically 600 seconds or one game day), the entire supply of water in the tank will be sterilized, becoming completely germ-free.
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Remove Chlorine Gas:
- Once the water is sterile, use the Gas Pump at the top of the chamber to pump out the chlorine gas. The excellent news is that the chlorine can be pumped out with no ill effects or pollution of the water. It does not contaminate the purified water, nor is it consumed in the process. You can store and reuse this chlorine for future sterilization batches.
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Extract Purified Water:
- Finally, pump out the now clean, germ-free water from the bottom of the chamber for your colony's needs, such as cooking, research, or hydration.
Example System Diagram
(Imagine a simplified diagram here)
[Gas Pump (Chlorine Out)]
[Gas Vent (Chlorine In)]
[Insulated Tiles]
[Chlorine Gas Layer]
[--------------------] <-- Water Surface
[Germ-Free Water]
[Liquid Vent (Water In/Out)]
[Insulated Tiles]Designing an Efficient Chlorine Disinfection System
To make this process seamless and automated, consider these design elements:
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Automation with Sensors:
- Use a Liquid Element Sensor near the bottom of your tank to detect when germy water is present and when the tank is full, controlling the incoming liquid pump.
- Use a Gas Element Sensor at the top of the tank to detect when chlorine gas is present. This can automate the chlorine pump, ensuring it only runs when needed.
- Employ a Liquid Shutoff valve for incoming germy water and a Gas Shutoff valve for incoming chlorine, controlled by automation wires.
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Chlorine Source: Chlorine gas can be obtained from natural gas vents (if they produce chlorine) or by off-gassing Bleach Stone, which is a solid material that naturally releases chlorine gas over time.
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Reusability: Since chlorine is not consumed, design your system to pump the used chlorine back into a storage tank or directly into the next sterilization chamber.
Advantages and Considerations
Benefits of Chlorine Disinfection
- Highly Effective: Kills virtually all germs in water.
- Material-Efficient: Chlorine gas is not consumed; it's reusable indefinitely.
- Scalable: Can sterilize large quantities of water efficiently over time.
- No Byproducts: Leaves behind perfectly pure, germ-free water without any chemical residues.
Important Considerations
- Initial Chlorine Supply: Requires a source and initial collection of chlorine gas.
- Dedicated Setup: Needs a specific, sealed chamber, which takes up space and resources to build.
- Time Commitment: Each batch requires a "full cycle" of contact time for complete sterilization.
- Duplicant Safety: Chlorine gas is toxic to Duplicants. Ensure your sterilization chamber is completely sealed, or use Atmo Suits for Duplicants working nearby to prevent exposure.
Comparison with Other Purification Methods
While other methods cleanse water, chlorine uniquely targets germs.
| Method | Primary Function | Germ Removal | Consumables | Energy/Time Cost |
|---|---|---|---|---|
| Chlorine Gas | Sterilization | Yes | None (reusable gas) | Time |
| Water Sieve | Polluted Water -> Water | No | Sand | Moderate Energy |
| Desalinator | Salt Water -> Water | No | None | Moderate Energy |
| High Heat | Sterilization | Yes | None | High Energy |
By understanding and implementing the chlorine disinfection method, you can ensure a reliable supply of germ-free water for your colony in Oxygen Not Included, significantly improving Duplicant health and base efficiency.
