Modvat credit for sulphuric acid used within the manufacturing stream was upheld as an eligible input.

Sulphuric acid added to caustic soda solution in the alumina manufacturing process was treated as an eligible Modvat input because it functioned within the production stream by regulating reaction rate, improving heat transfer, and preventing scale deposition. It was not used as a separate cleaning agent, but as part of the manufacturing operation itself, bringing it within the broader understanding of input used in or in relation to manufacture under Rule 57A. On that basis, Modvat credit was allowable and the disallowance was unsustainable.

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Issues: Whether sulphuric acid added to the caustic soda solution used in the manufacturing process qualified as an eligible input for Modvat credit under Rule 57A.

Analysis: The acid was not used independently to remove scales. It was added to the caustic soda solution used in processing alumina, and in that setting it assisted the manufacturing operation by regulating production rate, improving heat transfer, and preventing scale deposition. On that basis, it was treated as having entered the stream of manufacture and as falling within the extended understanding of input used in or in relation to manufacture.

Conclusion: The input was eligible for Modvat credit, and the disallowance was unsustainable.

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