Sulfuric acid (H₂SO₄) is the “lifeblood” of industrial production, widely used in chemical, metallurgical, pharmaceutical, fertilizer, and environmental protection fields. The sophistication of its production process directly determines product quality, energy consumption, and environmental benefits. Tianli specializes in sulfuric acid production from sulfur, employing mature and advanced end-to-end production processes covering sulfur combustion, SO₂ conversion, SO₃ absorption, and finished product processing. Leveraging our comprehensive technological advantages, we create high-purity, low-energy-consumption, and environmentally friendly sulfuric acid products, providing one-stop production solutions for various industries and contributing to high-quality industrial development.
I. Core Material Properties
Sulfuric acid is a colorless, oily liquid with the molecular formula H₂SO₄, relative molecular mass of 98.08, density of 1.84 g/cm³, and boiling point of 338℃. It is highly corrosive, hygroscopic, and dehydrating. Sulfuric acid (H₂SO₄) releases heat violently when miscible with water; therefore, acid must be added to water during dilution.
II. Core Process Flow Introduction
The sulfur-to-sulfurization process employs a closed-loop flow: sulfur combustion → SO₂ catalytic conversion → SO₃ absorption → product concentration. Each step is tightly integrated and fully controllable, as detailed below:
1. Sulfur Pretreatment: raw sulfur is crushed and sieved to remove impurities and agglomerates, resulting in uniformly sized sulfur powder. This powder is then dried to remove surface moisture (≤0.1%) to avoid affecting combustion efficiency and subsequent reactions. The pretreated sulfur is then fed into the combustion furnace through sealed conveyor to prevent dust leakage.
2. Sulfur Combustion: the pretreated sulfur enters a combustion furnace and is fully combusted in a high-temperature (1000-1100℃) oxygen-rich environment to generate sulfur dioxide (SO₂) gas. The reaction equation is S + O₂ → SO₂. During combustion, the air supply is precisely controlled to ensure complete sulfur combustion, maintaining a stable SO₂ concentration of 10%-12%. A dust removal device is also installed to remove small amounts of dust from the combustion flue gas.
3. SO₂ Catalytic Conversion: SO₂-containing flue gas is cooled to 420-450℃ by a waste heat recovery device and enters the converter. Under the action of a vanadium catalyst, SO₂ is gradually converted into sulfur trioxide (SO₃). A two-conversion, two-absorption process is adopted, that is, after the first conversion, part of the SO₃ is absorbed by the absorption tower, and the remaining gas is reheated and re-enters the converter, ensuring that the SO₂ conversion rate is ≥99.8%, significantly improving the utilization rate of raw materials.
4. SO₃ Absorption: the converted SO₃-containing flue gas enters the absorption tower, where 98.3% concentrated sulfuric acid is used as the absorbent. SO₃ is absorbed in countercurrent contact to generate fuming sulfuric acid. According to market and customer needs, through a precise dilution process, the fuming sulfuric acid or the absorbed concentrated sulfuric acid is adjusted to different concentrations of industrial-grade sulfuric acid, such as 93% or 98%, or further prepared into dilute sulfuric acid to obtain finished sulfuric acid that meets the corresponding industry standards. Temperature and absorbent concentration are strictly controlled during the absorption process to avoid acid mist and reduce environmental pollution.
5. Finished Product Processing and Tail Gas Purification: finished sulfuric acid is cooled, filtered to remove impurities, and only after passing inspection can it be packaged and stored. The tail gas after absorption undergoes desulfurization and demisting treatment to ensure that the SO₂ emission concentration is lower than industry standards, achieving clean production. The heat recovered by the waste heat recovery device can be used for production preheating, achieving energy recycling.
III. Core Technological Advantages
1. Technological Advantages: utilizing a mature “two-conversion, two-absorption” core process, combined with a high-efficiency vanadium catalyst and boiling combustion technology, the SO₂ conversion rate is ≥99.8%, resulting in high raw material utilization. The entire process is mature and stable, with convenient equipment operation and maintenance, enabling continuous and large-scale production, adapting to different output demands, and effectively addressing fluctuations in raw material purity to ensure stable production.
2. Energy Consumption Advantages: equipped with a high-efficiency waste heat recovery system, it recovers waste heat generated during sulfur combustion and SO₂ conversion for use in raw material drying and process preheating, significantly reducing external energy consumption. The "two-conversion, two-absorption" process reduces reaction energy consumption, with overall energy consumption reduced by more than 20% compared to traditional processes, significantly lowering production costs.
3. Environmental Advantages: the entire production process is conducted in a closed system, equipped with high-efficiency dust removal, desulfurization, and demisting devices. The SO₂ emission concentration in the exhaust gas is lower than industry standards, and there is no acid mist leakage. No wastewater is generated during production; wastewater is recycled to achieve zero discharge, aligning with the green and low-carbon development concept and meeting environmental emission requirements.
4. Product Advantages: we can flexibly produce sulfuric acid of various concentrations, including 93% and 98% concentrated sulfuric acid, dilute sulfuric acid, and fuming sulfuric acid, to meet diverse needs across multiple industries. Through precise control of reaction parameters at each stage, the finished sulfuric acid achieves the required purity standards, with low impurity content, stable concentration, and no odor or sediment. It is suitable for applications in fertilizers, chemicals, metallurgy, water treatment, and pharmaceuticals, and its product quality far exceeds industry standards, giving it strong market competitiveness.
5. Control Advantages: equipped with a fully automated DCS control system, it monitors key parameters such as sulfur combustion temperature, SO₂ concentration, conversion efficiency, and absorbent concentration in real time, achieving precise control throughout the entire process. Operation is convenient, reducing manual intervention and human error, ensuring stable production and consistent product quality.
We empower production with technology and build quality with expertise. Based on the material characteristics of sulfur and sulfuric acid, our company has deeply explored the entire process of sulfuric acid production. Leveraging our comprehensive advantages in technology, energy consumption, and environmental protection, we provide high-quality sulfuric acid products and integrated production solutions to various industries, helping enterprises reduce costs, increase efficiency, and meet environmental standards, thus promoting green and sustainable industrial development.