Taking a page from real-life alchemy, there could be a machine that requires Neutralized Salt (any two opposing elements - ordo+perditio, aqua+ignis, terra+aer) to work, and which would allow transmuting the primals into each other based on a reaction chain (Ordo > Terra > Aqua > Perditio > Aer > Ignis > Ordo for example) to make surplus essentia more manageable.
Taking a page from real-life alchemy, there could be a machine that requires Neutralized Salt (any two opposing elements - ordo+perditio, aqua+ignis, terra+aer) to work, and which would allow transmuting the primals into each other based on a reaction chain (Ordo > Terra > Aqua > Perditio > Aer > Ignis > Ordo for example) to make surplus essentia more manageable.