Seawater Salt Production Plant
Seawater salt production is a traditional and important chemical industry. Finished salt is widely used in food processing, pharmaceuticals, chemicals, and livestock farming. The sophistication of its production equipment directly determines product quality, production efficiency, and environmental performance. Our company has deep expertise in seawater salt production, developing complete standardized seawater salt production facilities that integrate the entire process from beach drying, purification, crystallization and concentration to drying. Relying on advanced technology and intelligent control, we achieve efficient utilization of seawater resources, providing customers with green, efficient, low-consumption, and intelligent production solutions to support the industry's large-scale and sustainable development.
1.Core material properties
Fresh seawater has a salt concentration of approximately 3.5%, of which sodium chloride accounts for about 77%, with the remainder being magnesium chloride, magnesium sulfate, calcium sulfate, and various trace elements. During concentration and purification, the solubility of each component in the brine changes, impurity ions are gradually removed, and the purity of sodium chloride continuously increases. After crystallization, the wet salt has a moisture content of approximately 3%–5%, and the final product's moisture content needs to be controlled below 0.2% to ensure fluidity and shelf life.
II. Introduction to Core Processes
I. Solar Process
Seawater is introduced into vast evaporation fields, where it evaporates naturally using sunlight and wind. The fields are designed with a concentration gradient, consisting of primary, intermediate, and advanced evaporation ponds, allowing seawater to gradually increase in concentration to around 20°Bé.
II. Purification
The concentrated brine was nearly saturated with calcium sulfate, and the levels of impurity ions such as magnesium sulfate and magnesium chloride were elevated. A brine purification method was employed, first adding a calcium preparation to remove sulfate ions, then adding sodium carbonate to remove calcium and magnesium ions. After the reaction, precipitation and separation occurred, yielding high-purity refined brine.
III. Evaporation
The purified brine is introduced into a multi-effect evaporation system or a large-area evaporation tank, where low-temperature, high-efficiency evaporation is achieved through vacuum evaporation technology. The brine is concentrated from 25°Bé to 28°Bé to approximately 30°Bé, reaching the critical state for crystallization.
IV. Crystallization
Staged crystallization or vacuum forced circulation crystallization is employed. The supersaturation of the brine is controlled between 1.02 and 1.05, and the temperature is maintained at 50℃ to 60℃. The crystal slurry circulates and grows in the crystallizer. The crystals are discharged after reaching a particle size of 0.3mm to 0.8mm.
V. Drying
After being centrifuged and dehydrated, the wet salt enters a dryer where the hot air temperature is controlled to dry and dehydrate it. After cooling, it is ready to be a qualified finished product with a final moisture content of less than 0.2%.
III. Core Technical Advantages
1. Technical advantages: it integrates the entire process of beach drying, purification, concentration, crystallization and drying, with mature and stable technology that is suitable for different seawater qualities in different sea areas; it adopts multi-effect evaporation crystallization and internal heating fluidized bed drying technology, which has high crystallization efficiency and uniform drying. The heat utilization rate of the internal heating fluidized bed is more than 30% higher than that of traditional drying equipment; the modular design of the equipment makes operation and maintenance convenient, and it can realize continuous and large-scale production to meet different production capacity requirements.
2. Energy consumption advantages: the beach drying section makes full use of natural sunlight and wind power, which greatly reduces external energy consumption; the combination of multi-effect evaporation and waste heat recovery system recovers waste heat from the drying and concentration process, and the overall energy consumption is reduced by more than 25% compared with traditional seawater salt production equipment, which significantly reduces the company's production costs.
3. Environmental advantages: the entire production process adopts a closed system, and the exhaust gas is purified before being discharged, with dust concentration lower than the industry standard; production wastewater is recycled to achieve zero wastewater discharge; by-products are recycled and reused, and no harmful waste is generated, which is in line with the concept of green and low-carbon development and fully meets environmental emission requirements.
4. Product advantages: the finished salt has a purity of ≥99.5%, uniform particle size, is not easy to clump, and has no impurity residue. It can be flexibly produced in two specifications: food grade and industrial grade, to meet the needs of multiple fields. The product meets relevant national standards, has a pure taste, stable quality, and strong market competitiveness.
5. Control advantages: Equipped with a fully automatic DCS intelligent control system, it monitors key parameters such as seawater concentration, purification accuracy, crystallization rate, and drying moisture in each process section in real time, achieving precise control throughout the entire process. It has automatic alarm and emergency shutdown functions, can be operated remotely, reduces manual intervention, ensures stable and safe operation of the equipment, and ensures uniform product quality.
Empowering marine resource utilization with technology and crafting high-quality salt with expertise. Tianli focuses on the core needs of seawater salt production, creating efficient, environmentally friendly, and intelligent production facilities. Leveraging our comprehensive advantages in technology, energy consumption, and environmental protection, we provide complete seawater salt production solutions for various industries, helping enterprises reduce costs, increase efficiency, and achieve green development, thereby promoting the industrial upgrading of efficient seawater resource utilization.