Why the exact LG Energy Solution Vietnam RO capacity is not yet verifiable
A verified RO capacity for LG Energy Solution’s new battery plant in Vietnam cannot be stated because the supplied evidence contains no published project wastewater flow, process-water balance, line count, RO recovery target or stream-specific chemistry. Production output cannot replace those inputs. The defensible route is to separate each wastewater source, route it through pretreatment, and calculate feed, permeate, concentrate and thermal duty from one agreed water balance. A published battery-project precedent achieved up to 80% RO recovery, while an industrial RO catalogue specifies up to 95%; neither establishes this plant’s capacity.
The 2025 Nature study cited by HydropureWater provides production-line context: one line represents 7 GWh/a for LFP cells or 8 GWh/a for NMC811 cells, and its gigafactory model contains four parallel lines. It does not provide an LGES Vietnam treatment design or establish how many lines will operate at each production stage. Cell manufacturing and cathode active material production must also remain separate: cathode production can add metal-, fluoride- and solvent-bearing streams that differ from cell assembly. Transferring those assumptions would corrupt both the RO feed and the concentrate calculation.
The CATL Vietnam gigafactory ZLD sizing methodology provides the same separation of treatment hydraulic capacity, membrane recovery and thermal duty. Apply that framework to the actual LGES Vietnam water balance rather than adapting another company’s project figures.
| Evidence class | What is available | Calculation variable | Claim that cannot be made |
|---|---|---|---|
| Published project data | 2025 Nature production-line context: 7 GWh/a for LFP cells, 8 GWh/a for NMC811 cells, and a four-line gigafactory model | Production configuration and operating schedule | That production output determines wastewater flow or RO capacity |
| LGES Vietnam calculation variables | No published wastewater flow, water balance, line count, recovery target or stream chemistry in the supplied research | Source-separated average and peak flows; selected recovery; concentrate route | That a numerical m³/h requirement is verified |
| Equipment precedent | Memva project: up to 80% RO-stage recovery; industrial RO catalogue: up to 95% recovery | Recovery scenarios requiring membrane and fouling verification | That either figure is an LGES Vietnam guarantee |
| Unrelated commercial benchmark | 50–200 m³/h for Indonesian precursor-plant packages | Inquiry-envelope sensitivity only | That the range is an LGES Vietnam flow, RO feed or ZLD duty |
The wastewater streams that determine RO loading
RO loading should be built from source-separated wastewater, not from a factory-wide average. Request separate flows for cell manufacturing, cathode active material production, coating, cleaning, rinsing, floor and equipment washing, laboratory streams, cooling-water blowdown, domestic wastewater and stormwater contacts. For each stream, obtain average and peak flow, operating hours, batch-discharge profile, temperature, TDS or conductivity, COD, TSS, metals, fluoride, pH, alkalinity, oils, solvents, reuse destination and discharge route.
Source separation determines both contaminant removal and hydraulic sizing. Dedicated solvent recovery should be considered where NMP or another relevant solvent is present; sending that stream directly to RO would add an organic load that may require a different membrane, control system or upstream recovery unit. The engineering basis for heavy-metal removal before industrial RO should therefore be applied only after stream composition is established.
Equalization can reduce peak hydraulic loading without reducing the daily water and salt mass requiring treatment. That distinction matters: tankage may govern peak transfer and batch discharges, while daily salt mass governs storage duration, reagent consumption and thermal-treatment operating hours. It also means an RO feed averaged across the day must not be treated as evidence that the membrane train can accept every instantaneous discharge.
The Memva case reported TDS above 30,000 mg/L, COD of 3,500 mg/L and fluoride at 180 mg/L. Those values characterize one battery cathode-material and coating wastewater project; they are not LGES Vietnam design data. A comparison of relevant removal methods is covered in the guide to heavy-metal wastewater treatment for industrial applications.
| Stream group | Required flow data | Required characterization | Design decision |
|---|---|---|---|
| Manufacturing, coating, cleaning and rinsing | Average, peak, batch profile and operating hours | COD, TDS or conductivity, TSS, metals, fluoride, pH, alkalinity, oils and solvents | RO feed, dedicated pretreatment or separate recovery |
| Floor and equipment washing | Collection peak, wash-cycle duration and reuse route | Suspended solids, oils and cleaning chemicals | Equalization and solids-removal duty |
| Laboratory streams | Discrete discharges and drain configuration | Acid/alkalinity profile and metals | Segregation and neutralization |
| Cooling-water blowdown and domestic wastewater | Makeup, cycles of concentration, discharge frequency and occupancy | TDS, conductivity, COD and temperature | RO inclusion, alternative treatment or reuse |
| Stormwater contacts | Contaminated-runoff event flow and isolation status | Suspended solids, metals and oil | Segregation; no uncontrolled RO feed |
Calculate RO feed, permeate and concentrate from the water balance
Define RO feed, Q, as the sum of source-separated flows routed to RO after pretreatment, excluding bypasses and flows assigned directly to another treatment route. For a selected recovery R, calculate permeate as Q × R and RO concentrate as Q × (1 − R). Then revise the concentrate allocation for bypasses, side-stream treatment, additional recovery and operating-hour constraints.
This calculation separates three capacities that are frequently conflated:
- Pretreatment hydraulic capacity is the liquid flow the plant can accept.
- RO feed and permeate rates describe membrane loading and water recovery.
- Thermal duty is based only on the concentrate assigned to evaporation or crystallization.
The symbolic thermal-feed expression is:
Concentrate to thermal treatment = Q × (1 − R) − any separately routed concentrate.
If part of the RO concentrate goes to another route, it cannot also be included in the evaporator feed. Likewise, an additional recovery stage changes the water split entering thermal treatment. The final flowsheet must identify where every liquid stream goes. Use the same basis when evaluating an industrial reverse osmosis system for battery wastewater.
Memva reported up to 80% RO-stage recovery, while HydropureWater’s industrial RO equipment specification states recovery up to 95%. The first is a project outcome; the second is a maximum catalogue capability. Neither determines an LGES Vietnam guarantee. Recovery must be demonstrated against the actual feed salinity, fouling potential, membrane compatibility, scaling constituents, operating hours and concentrate route.
| Input or output | Formula or method | Unit | Source status | Responsibility |
|---|---|---|---|---|
| RO feed, Q | Sum of characterized streams routed to RO after pretreatment | m³/h | Missing for LGES Vietnam | Project engineer and wastewater operator |
| Selected recovery, R | Approved membrane scenario tied to feed conditions | fraction | Missing for LGES Vietnam | Project engineer, operator and RO vendor |
| RO permeate | Q × R | m³/h | Conditional calculation | Project engineer |
| Initial RO concentrate | Q × (1 − R) | m³/h | Conditional calculation | Project engineer |
| Thermal-feed flow | Initial concentrate less separately routed portions | m³/h | Missing until routing is fixed | EPC contractor |
| Thermal operating hours | Approved batch or continuous schedule | h/day or h/year | Missing for LGES Vietnam | Operator |
| Permeate quality | Contract limit against agreed sampling method | Specified parameter | Not supplied | Project engineer and vendor |
Match pretreatment and RO to the contaminant load
A screening treatment train for battery manufacturing wastewater starts with segregation and equalization, chemical precipitation for metals and bulk fluoride, clarification or DAF for generated solids, dedicated solvent recovery where relevant, membrane polishing, and thermal concentration or crystallization. This is a design framework rather than confirmation of the LGES Vietnam flowsheet. Sequence, reagents and equipment capacity depend on the measured streams.
DAF should be checked against peak flow, suspended and precipitated solids, oil, flotation loading and sludge characteristics. HydropureWater’s 2026 DAF catalogue spans 4–300 m³/h across 13 standard models, but a catalogue range does not size the plant. The Hungarian gigafactory sizing review provides the same warning: equipment ratings do not replace a characterized design envelope. Any DAF pretreatment for generated battery-wastewater solids should therefore be selected against the actual peak and solids load.
RO selection should then address required permeate recovery, feed salinity, scaling and fouling, membrane compatibility and the concentrate-management route. Solids need a separate balance because hydroxide or sulfide sludge properties determine dewatering, containerization, storage and final hazardous-waste handling. A plate-and-frame sludge dewatering system must be assessed from sludge chemistry and dewatering performance; dewatered sludge volume cannot be inferred from wastewater flow.
The supplied research cites QCVN 40:2011/BTNMT limits of Pb below 0.1 mg/L, Ni below 0.5 mg/L and Cd below 0.05 mg/L. Do not assume these historical values automatically apply to the LGES facility. The environmental adviser and permitting authority must confirm current Vietnamese discharge, reuse and hazardous-waste requirements.
| Design element | Screening basis | Required project evidence | Capacity check |
|---|---|---|---|
| Equalization and pumping | Source-separated peak and batch profile | Flow recording and operating schedule | Peak inflow, storage duration and turndown |
| Chemical precipitation | Metals, fluoride, pH, alkalinity and reagent demand | Laboratory analysis and precipitation trials | Dose, sludge generation and mixing |
| DAF or clarification | Suspended solids, precipitated solids and oil | Solids loading and flotation trials | Peak flow and flotation loading |
| RO | Permeate recovery, salinity, fouling and scaling | Membrane feed analysis and pilot or design data | Feed, permeate, concentrate and pressure |
| Sludge treatment | Hydroxide or sulfide sludge properties | Dewatering test and hazardous-waste classification | Press capacity, cake characteristics and destination |
Turn the sizing basis into an auditable supplier RFQ
The RFQ should define an influent envelope containing average and peak wastewater flow, operating hours, source-separated flows, TDS or conductivity, metals, fluoride, COD, TSS, solvents and temperature. It should also state the proposed RO recovery range, permeate quality, concentrate split, evaporator-feed rate, required crystal or concentrate output, utility requirements and reuse destinations.
Separate equipment supply from EPC scope. Identify civil works, chemical storage, hazardous-sludge handling, utilities, controls, operator training, commissioning and long-term maintenance explicitly. Otherwise, a packaged price can conceal major interfaces and future operating costs.
Require measurable acceptance tests for permeate quality, recovery, liquid-discharge performance, crystal output and residue characteristics. Each bidder should identify exclusions, schedule, training, warranty, startup support and performance obligations against the same reference flowsheet. This approach follows the procurement logic in the effluent-treatment-plant buyer guide, where comparable bids require a common design basis.
No responsible CAPEX or OPEX figure can be stated from the supplied evidence because the LGES Vietnam design flow, flow profile and influent chemistry are absent. Pricing should follow characterization, not precede it. A bidder can still submit a budgetary offer, but it must identify assumptions, exclusions and the reference envelope used for every price.
| RFQ package | Minimum content | Bidder response | Evaluation check |
|---|---|---|---|
| Influent envelope | Source-separated average and peak flow, hours, chemistry and temperature | Confirm design cases and operating hours | All bids use the same envelope |
| RO and concentrate route | Recovery range, permeate quality, concentrate split and thermal-feed rate | Show the complete mass balance | No double-counted or unallocated flows |
| Scope boundary | Civil works, chemicals, ZLD, sludge handling, utilities, controls and services | List inclusions and exclusions | Comparable commercial structure |
| Acceptance tests | Permeate, recovery, discharge, crystal output and residue criteria | State test method, conditions and protocol | Guarantee tied to reference conditions |
| Commercial terms | Price, schedule, warranty, startup, training and maintenance | Price each defined scope | Capacity and performance are priced consistently |
Choose equipment against the project basis, not a copied benchmark
The 50–200 m³/h range in HydropureWater’s 2026 article applies to Indonesian precursor-plant packages. It is useful only as an order-of-magnitude inquiry check; it is not an LGES Vietnam wastewater flow, RO feed or ZLD duty. Likewise, catalogue recovery of up to 95% is a maximum equipment capability rather than proof that the actual plant will recover 95% of its feed.
Evaluate each offer against three distinct commitments: the LGES project requirement, the evidence class behind each benchmark, and the supplier’s contractual commitment. The missing evidence must remain visible until the project water balance and characterization are complete.
| Project-specific requirement | Published precedent | Supplier commitment | Missing evidence |
|---|---|---|---|
| LGES source-separated RO feed | No project flow published in the supplied research | Offer must state its reference design flow | Approved process-water balance |
| Approved RO recovery | Memva: up to 80% project-stage recovery | Guaranteed recovery under the agreed feed | Feed salinity, fouling and recovery study |
| Equipment capability | RO catalogue: up to 95% recovery | State operating envelope and exclusions | LGES-specific membrane performance basis |
| Thermal duty and residue route | No LGES Vietnam duty published | Guarantee feed rate, operating hours and product characteristics | Concentrate routing and mass balance |
Frequently Asked Questions
Can the required RO capacity be calculated today?
No verified numerical capacity can be calculated from the supplied evidence because the LGES Vietnam wastewater flow, process-water balance, approved recovery rate and stream chemistry are unavailable. The defensible output today is the calculation worksheet and a list of required project inputs. Assign actual values only after the project engineer and operator approve the source-separated water balance.
What is the fastest way to obtain a budget-grade capacity?
Request source-separated average and peak flows, operating schedules, representative chemical analyses, reuse destinations and the selected recovery and concentrate route. Then require every vendor to complete the same design-basis table. This check establishes whether offers share one capacity basis; a price quoted against an undefined flow is not comparable.
Can the 80% Memva recovery or 95% HydropureWater specification be used for LGES Vietnam?
No. The 80% figure is a published battery-project outcome, while 95% is an equipment specification. Neither is an LGES Vietnam guarantee. Recovery should be selected against the actual feed salinity, fouling potential, scaling constituents, membrane compatibility and concentrate route, then supported by a measurable acceptance test.
How should suppliers be compared for delivery and performance?
Compare bids against the same influent envelope, permeate requirements, recovery scenario, concentrate route, utilities, sludge scope and acceptance tests. During supplier selection, ask each bidder to identify exclusions, delivery schedule, startup support, operator training, warranty scope and performance obligations. This review aligns with the Vietnam gigafactory ZLD sizing methodology without transferring another project’s capacity to LGES.
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