Whether your tank and/or tank lining material of construction is compatible with your waste will depend on many variables, including temperature, composition, trace impurities, etc. You need to fully characterize your waste and then complete an assessment on its compatibility with the materials of construction under consideration. You mentioned stainless steel and asked what thickness of material to use to "avoid corrosion". Assuming you are asking about an austenitic stainless steel like 304 or 316, if these are attacked, they most often suffer localized corrosion and not uniform corrosion. A corrosion allowance or use of a thicker material of construction to prolong equipment life offers little protection against localized corrosion such as pitting, crevice corrosion, stress corrosion cracking, etc. If you decide to go the lined tank route you should work with a tank lining manufacturer to help you select the appropriate lining material and get recommendations for proper surface preparation prior to application of the lining material.