3 t/h electrolyte lithium extraction MVR evaporator

I. Project Overview

Owner: A lithium iron phosphate cathode material manufacturer with an annual production capacity of 50,000 tons

Operating Conditions: Battery-grade Li₂CO₃ lithium precipitation mother liquor 3 t/h, Li⁺ 2.2 g/L, Na⁺ 65 g/L, CO₃²⁻ 45 g/L, pH 11, containing trace amounts of P, F, and Fe; The original system used triple-effect evaporation + centrifuge, resulting in lithium entrainment loss >8%, steam consumption of 0.42 t/t, high operating costs, and significant white fog on-site.

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.

II.Cooperation Process (Milestone Nodes)

1.Laboratory Pilot-Scale Test (7 days): Conqinphi's own comprehensive water sample laboratory completes the Li-Na-CO₃-H₂O quaternary phase diagram determination, verifying that the lithium loss of the MVR+freezing salt separation route is <0.5%.

2.Pilot-Scale Verification (30 days):On-site 5 m³/d skid-mounted pilot-scale test, continuous operation for 720 h, lithium yield 98.3%, owner issues acceptance report.

3.Process Package & Commercial Contract Signing:Submission of PFD, PID, equipment list, and guaranteed energy consumption values; completion of technical agreement and contract signing within 15 days.

4.Detailed Design:Completion of design drawings, stress calculations, and other reports within 30 days, meeting lithium battery safety production standards.

5.Equipment Manufacturing:Titanium evaporators, separators, heat exchangers, mother liquor drying system, preheating system, etc., are simultaneously manufactured in the factory.

6.Installation and Commissioning:Skid-mounted shipment + on-site flange connection, mechanical completion within 15 days; water and salt intermodal transport and performance testing completed within 30 days.

7.Performance Testing:72-hour continuous testing: lithium recovery rate 98.5%, steam consumption 0 t, power consumption 26.8 kWh/t, passed acceptance on the first attempt.

8.Operation and Maintenance Training:SOPs, inspection checklists, and VR training system provided; 100% certification rate for owner's operators.

III.System Configuration and Process Highlights

1.Process Route

MVR Falling Film Concentration → Forced Circulation Flash Crystallization → Cryogenic Denitrification → Centrifugal Drying → Battery-Grade Li₂CO₃ Recycling

2.Key Equipment

Falling Film Evaporator: 180 m² heat exchange area, titanium/titanium composite plate, resistant to CO₃²⁻ stress corrosion;

Compressor: 24 ℃ temperature rise, 85% isentropic efficiency, 10-100% frequency conversion, 5-year maintenance cycle;

Forced Circulation Crystallizer: φ2.2 m guide tube + washing legs, particle size 0.4-0.8 mm >70%;

Mother Liquor Drying: Rake dryer, residue moisture content <5%, exempt from landfill according to HW18.

3.Control Strategy

PLC Automatic Control System: Evaporation endpoint density ±0.002 g/cm³, compressor surge margin >15%;

Online lithium-sodium analyzer (ICP-OES) + AI predictive cleaning, scaling early warning accuracy 96%;

Seamless integration of the entire plant's DCS with the owner's MES, data granularity 1 second, supporting remote operation and maintenance via Web/APP.

IV. Operational Data (Performance Assessment - May 2025)

1.Processing Capacity: 3.0 t/h (Design value 100%)

2.Lithium Recovery Rate: 98.5% (> Contractual Target 98%)

3.Power Consumption: 26.8 kWh/t (including refrigeration and drying)

4.Live Steam: 0 t (Shut down after <30 min of preheating)

5.Byproduct Na₂CO₃·10H₂O: 0.9 t/d, purity 99.1%, sold to glass factories for 400 RMB/t

6.System Operating Rate: 8,300 h/a (First year of assessment)

7.Cleaning Cycle: 90 days (Oxalic acid + ultrasonic combined, completed in 6 hours)

V.Summary of Technical Advantages

1.Industry-leading Lithium Recovery Rate: Precise phase diagram control + cryogenic denitrification, mother liquor Li⁺ <0.04 g/L, loss <0.5%. 2.Extreme Energy Saving: MVR + falling film + magnetic levitation, saving 65% more electricity than traditional three-effect systems, resulting in annual electricity cost savings of 3.2 million yuan.

3.Long-Term Stability: Titanium materials + duplex steel, resistant to CO₃²⁻/F⁻/P⁻ corrosion, equipment lifespan >12 years.

4.Modular Delivery: 90% factory prefabrication rate, reducing on-site installation by 70% and shortening the construction period by 30%.

5.Zero Steam, Zero White Mist: Fully enclosed system, 100% compressed and reused secondary steam, no visual pollution on site.

VI.Full Lifecycle Service:

1.Warranty Period: 1 year, compressor free of major overhaul for 5 years;

2.Spare Parts Warehouse: Key spare parts arrive on-site within 48 hours;

3.Remote Operation and Maintenance: 7×24h cloud monitoring, dedicated service engineer for one-on-one support;

4.Upgrade Service: Provides expansion interfaces for subsequent production increases to 5 t/h (with reserved compressor base and pipe connections). 5. Training System: Two technical follow-up visits per year; operator skill certification remains valid.

VII. Customer Value

After the project is put into operation, the owner will recycle 180 tons of battery-grade Li₂CO₃ annually, valued at RMB 14.4 million; save 38,000 tons of steam, equivalent to RMB 7.6 million; generate RMB 1.3 million in revenue from by-product Na₂CO₃; totaling RMB 23.3 million in annual economic benefits. Simultaneously, it achieves zero discharge of lithium-containing wastewater, laying an environmental foundation for the subsequent expansion of the 100,000-ton lithium iron phosphate project.