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An overview of sulfuric acid production and the utilization of the \"three wastes\" in sulfuric acid process titanium dioxide production. Sulfuric acid production methods: producing acid from sulfur； Acid production from iron ore ； Production of acid from smelting exhaust gases. Titanium dioxide production method: sulfuric acid method ； Chlorination method. Resources available for sulfuric acid production (taking sulfur-based acid production as an example) – Heat of combustion of sulfur ； Sulfur dioxide conversion heat ； Heat of absorption of sulfur trioxide ； Waste heat from exhaust gases. Resources that can be utilized in titanium dioxide production via the sulfuric acid method: waste acid ； ferrous sulfate ； Waste heat from calcination exhaust gases. Methods for concentrating dilute sulfuric acid (1): Direct method: Immersion combustion concentration method ； Drum concentration method ； (Kemico, USA) Venturi tube concentration methods (high-temperature and low-temperature methods), spray concentration methods (complete evaporation and partial evaporation methods). (II) Indirect heating concentration methods: 1. Pot concentration method (Pauling method); 2. Bayer-Bertrams method; 3. BOSAC method (BOFORS NOBEL CHEMATUR); 4. Vacuum evaporation concentration method: 1) SM (SIMONSON-MATIUS) type concentration apparatus: (1) SM method; (2) Japanese Kimura method; (3) Canadian CIL method. 2. Corning type sulfuric acid concentration apparatus; 3. Kemico flash membrane concentration apparatus. III. Comparison of the suitability of various sulfuric acid concentration methods and issues to note: 1. Initial and final concentrations of sulfuric acid (pre-concentration, moderate concentration, and high concentration); 2. Impurity content in sulfuric acid and their properties; 3. Uses of the concentrated acid. IV. Overview of the concentration and recovery of titanium dioxide waste acid in China: 1. Venturi tube method; 2. Spray (drip) method; 3. Vacuum evaporation method; 4. Crystallization concentration method. V. Combined production of sulfuric acid and titanium dioxide sulfate: (I) Integrated process for sulfuric acid production and concentration of dilute sulfuric acid used in titanium dioxide sulfate production: 1. Process for concentrating dilute acid using heat air from titanium dioxide calcination exhaust gas and sulfuric acid waste heat; 2. Process for preheating dilute acid using recycled sulfuric acid absorbed by sulfuric acid, as well as heat air from titanium dioxide calcination exhaust gas and sulfuric acid waste heat. (II) Integrated process for sulfuric acid production, titanium dioxide sulfate production, and recovery of dilute acid and ferrous ions