A process for increasing the concentration of sulfuric acid and equipment for use in the process

A stand-alone sulfuric acid concentrator system comprising

• a concentrator column having an inlet and an outlet,
• an optional sulfuric acid condenser column,
• a first air lift pump having a liquid inlet fed with hot concentrated sulfuric acid from the outlet of a concentrator column a gas inlet fed with a first carrier fluid, having a lower density than the hot concentrated sulfuric acid, and an outlet,
• a separating unit, in which the stream from first air lift pump is split into a hot sulfuric acid product stream directed to the sulfuric acid product cooler, a sulfuric acid stream for recirculation and said first carrier fluid being directed to the inlet of the concentrator column or to the bottom of the sulfuric acid condenser,
• a sulfuric acid product cooler for pre-heating a cold sulfuric acid feed stream by heat exchange with a hot concentrated sulfuric acid product stream,
• a second air lift pump, having a liquid inlet fed with the sulfuric acid stream for recirculation and the preheated sulfuric acid feed and a gas inlet fed with a second carrier fluid, having a lower density than the sulfuric acid stream for recirculation, and an outlet,
• an inlet pipe, said inlet pipe having an inlet and an outlet and an increased diameter compared to the riser pipe, said inlet pipe being configured for allowing a liquid flow from the inlet to the outlet and configured for at least partially separating sulfuric acid and second carrier fluid, and directing both fluids to the inlet of the concentrator column or to the bottom of the sulfuric acid condenser,
• a sulfuric acid reservoir located upstream of and above the first air lift pump, either integrated in the concentrator column or as a separate tank or vessel.