PH Neutralization Purification Unit

The pH Neutralization Purification Unit (NPU) is a ZPM tier multiblock used for the fourth step of the Water Line. It generates a random pH value when it starts running, and its pH must be brought to a neutral 7.0 for the recipe to succeed.

The NPU has no tiered components or energy hatches because it receives power directly from the Water Purification Plant once linked with a data stick, like the rest of the Water Line multiblocks. Use the Multiblock Structure Hologram Projector to visualize/build the structure.

Structure

• Controller: Front center, 2nd layer
• 134 Inert Neutralization Water Plant Casing
• 48 Naquadah Alloy Frame Box
• 18 Chemical Grade Glass
• 12-17 Stabilized Naquadah Water Plant Casing
• 0-2 pH Sensor Hatch: Below controller
• 1 Input Bus: Top of left chamber
• 2+ Input Hatch: Top of right chamber (hydrochloric acid), behind controller (water)
• 1+ Output Hatch: Behind controller

See More: Waterline#Shared Mechanics

At the start of each recipe cycle, the NPU will have a random pH value between 4.5 and 9.5, evenly distributed. Its success chance depends only on the current pH: it has a 100% success chance if the pH is between 6.95 and 7.05 at the end of the cycle, and a 0% chance otherwise. The pH can be modified by inserting a base (Sodium Hydroxide Dust) and an acid (Hydrochloric Acid) into the respective Input Bus or Input Hatch. Every 20 ticks (1 second), the NPU will consume all of these inputs, lowering the pH by 0.01 per 10L of Hydrochloric Acid consumed, and raising the pH by 0.01 per Sodium Hydroxide Dust consumed. If the pH ever reaches 0 or 14, the machine will shut down.

There are many methods of automating the NPU, but only one is discussed in detail here due to its simplicity and ease of implementation.

The core mechanic behind this approach is that, by moving precise amounts of acid or base each second, the pH can be gradually adjusted to the desired range without a risk of skipping over it.

• The pH Neutralization Purification Unit is the only multiblock whose name begins with a lowercase letter.
• There is an unimplemented easter egg in the NPU's code to destroy the glass if Fluoroantimonic Acid, the strongest known acid, is placed in the acid Input Hatch.