Thank you for your comprehensive comments.
It is indeed becoming more clear that the W.A.O quoted by the supplier is going to be only a fraction of the installed cost.
We are looking for a way to deal with a 5 m3 per hour waste caustic stream contaminated with sulphide, mercaptans and organics . C.O.D is approximately 40 grams per litre. We believe that wet air oxidation offers a good solution.
We are struggling to understand the total cost of installation...