Application Cases

High-Efficiency Concentration of Thermosensitive Chemical Wastewater: A 3-Ton/Hour Phosphate-Polyether Polyol Triple-Effect Evaporation System

A large pharmaceutical company generates approximately 50 tons of high-concentration sodium chloride wastewater daily during its active pharmaceutical ingredient (API) production process. This wastewater has a salt content as high as 8%–12% and contains small amounts of organic residues. Direct discharge would cause serious environmental pollution, while traditional treatment methods are energy-intensive and prohibitively expensive to operate. The company urgently needs a high-efficiency, stable, and economical evaporation and crystallization system to achieve resource recovery of sodium chloride and wastewater reduction.

This fine chemical company, located in the Yangtze River Delta Chemical Industrial Park in China, primarily produces pharmaceutical intermediates and specialty acetate esters. During production, it generates approximately 140 tons of dilute acetic acid wastewater daily, with an acetic acid concentration of only 5% to 8%, making direct outsourcing treatment prohibitively costly.

The company's main business is the synthesis of sulfide dyes and organic intermediates. Its hydrogenation reduction and sulfidation reaction processes generate approximately 24 tons of low-concentration sodium hydrosulfide solution daily, with a concentration of only 8% to 12%. Direct transportation for disposal is costly and carries significant transportation risks. To achieve the resource recovery and reuse of sodium hydrosulfide and eliminate the potential for hydrogen sulfide emissions, the company commissioned the construction of a single-effect vacuum evaporation and concentration unit in 2025, with a processing capacity of one ton per hour.

In the fields of fine chemicals, pesticide intermediates, and high-salinity wastewater treatment, the evaporation, concentration, and crystallization recovery of sodium chloride solution are crucial steps in achieving zero wastewater discharge and resource recycling. As one of the most common inorganic salts, the quality of sodium chloride's crystalline product directly impacts its downstream application value, while the energy consumption and stability of the evaporation system are related to the long-term operating costs of enterprises.

Sodium chloride, as a commonly used raw material salt, excipient, or reaction byproduct in pharmaceutical production, is widely present in wastewater from processes such as active pharmaceutical ingredient (API) synthesis, formulation production, and traditional Chinese medicine extraction and concentration. The recovery of sodium chloride from pharmaceutical wastewater not only involves resource reuse but also directly relates to environmental compliance and production cost control.

In the lithium battery industry chain, the evaporation and concentration of lithium sulfate solution and the recovery and treatment of byproducts such as sodium sulfate are crucial links in ensuring lithium salt quality and comprehensive resource utilization.

A large-scale electrolytic aluminum enterprise produces 500,000 tons of electrolytic aluminum annually. During the electrolyte recycling process, the lithium content continuously accumulates to 3-5%, leading to a decrease in electrolysis temperature and current efficiency. The enterprise is constructing a lithium recovery project with an annual processing capacity of 30,000 tons of lithium-containing electrolyte, employing a process route of "acid leaching purification + MVR evaporation concentration + cooling crystallization" to recover battery-grade lithium carbonate.

In the production and recycling of lithium-ion battery cathode materials, mixed wastewater rich in sodium sulfate and lithium sulfate is generated. This wastewater has a complex composition and high salt content, and traditional treatment methods often only allow it to be disposed of as hazardous waste, which is not only costly but also results in a significant waste of sodium and lithium resources. Faced with the urgent need for sustainable development in the lithium battery industry and increasingly stringent environmental regulations, a well-known lithium battery material manufacturer commissioned Conqinphi to design and build an industrial-grade solution capable of simultaneously recovering high-purity sodium sulfate and lithium sulfate from wastewater.

In the process of lithium battery recycling and cathode material production, a complex and highly corrosive lithium-containing waste electrolyte is generated. This electrolyte contains highly valuable lithium, but also contains impurities such as aluminum and iron, as well as fluorides. Traditional treatment methods result in low recovery rates, high costs, and are prone to secondary pollution. Faced with this common industry challenge, a leading battery recycling customer of Conqinphi urgently needed a dedicated system capable of efficiently and stably removing impurities from aluminum electrolyte and enriching and recovering lithium resources.

With the rapid development of the lithium battery industry, electrolyte recycling has become a crucial issue. Traditional electrolyte processing methods suffer from low lithium resource recovery rates, compromised electrolyte performance, and high energy consumption. A large lithium battery manufacturer faces a technological bottleneck in electrolyte recycling and urgently needs an innovative solution that can efficiently extract lithium while maintaining electrolyte performance.

Objectives: 1.Lithium recovery rate ≥98%, by-product Na₂CO₃·10H₂O reaching industrial grade; 2.Comprehensive energy consumption per ton of water ≤28 kWh, zero live steam replenishment; 3.System continuous operation ≥8,000 h/a, shutdown for cleaning ≤4 times/year; 4.Delivery cycle ≤4 months, 3-year warranty, full life-cycle service.

Facing this challenge, our company successfully designed, built, and put into operation this lithium carbonate MVR evaporation crystallization system with a processing capacity of 120 tons/day. This system, based on mechanical vapor recompression (MVR) technology, deeply integrates the physicochemical properties of lithium carbonate, achieving a high degree of efficiency, cost-effectiveness, and product quality in large-scale production, providing strong technical support for the client's sustainable development.

This bromine-phosphorus flame retardant manufacturer produces 23,000 tons of tetrabromobisphenol A and decabromodiphenyl ethane annually. The production process generates 5 m³/h of highly concentrated saline mother liquor with a complex composition: NaCl 12%, Na₂SO₄ 8%, sodium bromide 3%, zinc borate 1%, organophosphorus 0.5%, COD 20,000 mg/L, pH 1–2. The raw water is classified as HW18 hazardous waste, with an outsourced disposal cost of 2,800 RMB/ton and an annual cost of nearly 120 million RMB. The company urgently needs a comprehensive solution for "reduction of mixed salts + resource utilization".

Adhering to the circular economy concept of "turning waste into treasure," Kangqinfei designed and delivered a sodium chloride MVR evaporation crystallization system with a processing capacity of 3 tons/hour. This system employs mature mechanical vapor recompression (MVR) technology and precisely controls the crystallization characteristics of sodium chloride, successfully achieving the recovery of high-purity sodium chloride and near-zero wastewater discharge.

Based on a deep understanding of the characteristics of calcium chloride, Conqinphi designed and built a 2-ton/hour MVR forced circulation evaporation and concentration system for the client. This solution utilizes mechanical vapor recompression (MVR) technology as its core, combined with special anti-scaling and anti-corrosion designs, successfully concentrating the low-concentration calcium chloride solution to a high concentration, laying a solid foundation for subsequent resource utilization.

Addressing the client's pain points, Conqinphi customized a 2-ton/hour ammonium sulfate MVR evaporation crystallization system. The core of this solution is the use of MVR (Mechanical Vapor Recompression) technology, an advanced process, to achieve efficient, energy-saving, and environmentally friendly wastewater treatment and resource recovery.