Baihuipu Delivers Leachate Zero Liquid Discharge System
Baihuipu has delivered a leachate zero liquid discharge system for a mountain landfill in southwest China, where there is no receiving water and the evaporation pans had been overflowing in the wet season. The ZLD train was commissioned in February and processes 100 m3/d of leachate. A membrane concentration stage thickens the reject from the existing treatment plant, a mechanical vapour recompression evaporator drives off the water as distillate, and a crystallizer drops the salts, so no liquid leaves the site. The distillate returns as site water and the salt cake is sent for disposal, which ended the overflow risk that had threatened the landfill operating licence.
Key Features and Benefits
Concentrate Before You Evaporate
Evaporation is the expensive step, so throwing raw reject at it wastes energy. A membrane concentration stage first thickens the reverse osmosis reject from around 8 percent total dissolved solids to near 18 percent, which roughly halves the volume the evaporator must boil and cuts the steam and power bill proportionally. For the reuse angle specifically, Baihuipu Releases DTRO Membrane System for Leachate system goes further than we can here.
We set out the wider process route in refractory wastewater biodegradability.
The concentration stage was tuned to the leachate salt profile so scaling inside the membranes stayed manageable, with antiscalant and periodic cleaning built into the operating plan rather than added after a failure. For the reuse angle specifically, Baihuipu Launches Containerized Seawater Desalination Plant goes further than we can here.
MVR Evaporation Recovers Most of the Energy
A mechanical vapour recompression evaporator compresses its own vapour to reuse the latent heat, which is far more efficient than a steam-heated kettle and is what makes ZLD affordable at this scale. The distillate it produces is clean enough for site dust suppression and equipment washing. Where several streams need joint treatment, baihuipu puts textile water reuse system into operation is the more detailed reference.
The evaporator runs on electricity with no continuous fossil steam demand, which suited the mountain site where a steam header was not available. Fouling was managed with a scheduled clean and an online fouling-trend alarm rather than a fixed interval.
A Crystallizer Closes the Solid Loop
The evaporator bottom stream still carries dissolved salts, so a crystallizer drops them as a damp salt cake that is sent for appropriate disposal, leaving no liquid to discharge. The cake is characterized before removal so it goes to the right facility rather than a general landfill.
Numbers from Comparable Installations
For comparison, our 2022 project in Chengdu, Sichuan ran at 76 m³/day with influent COD near 2,000 mg/L and treated water around 300 mg/L. That is 85% removal in practice, not on paper.
| Location | Year | Flow | Feed COD | Treated COD | Removal |
|---|---|---|---|---|---|
| Chengdu, Sichuan | 2022 | 76 m³/d | 2,000 mg/L | 300 mg/L | 85% |
Figures are site-measured values from commissioned plants, not modelled estimates.
The whole train is instrumented for feed, distillate and cake mass so the operator can confirm no liquid is leaving and the water balance is closing. Quarterly salt characterization tracks the disposal route as the leachate chemistry drifts.
Technical Specifications
Leachate reject through the zero liquid discharge train:
| Parameter | RO Reject In | Distillate Out |
|---|---|---|
| Total dissolved solids | around 8 percent | below 500 mg/L |
| Volume to crystallizer | full reject | thickened to near 18 percent |
| Distillate use | not produced | site dust and wash water |
| Liquid discharge | risk of overflow | zero |
| Design flow | as generated | 100 m3/d continuous |
Why Choose Baihuipu as Your Manufacturer
Choosing a manufacturer here comes down to one question: who is still accountable once the commissioning team flies home. Our answer is that we build and programme our own equipment, then stand behind it for the life of the plant.
Manufacturing Base in Guangdong
Owned production lines mean we control tolerances, materials and delivery. Standard modular units and bespoke skids are both built by our own people, so schedule commitments are ours to keep.
Experience Built the Hard Way
Since the early 2000s we have commissioned plants for food and beverage processors, chemical works, electroplaters, textile mills, mines and municipalities. The lessons that stick are scaling, fouling and sludge handling — those inform every design we issue.
Certification and Export Practice
CE marking is standard and we work to ISO 9001 procedures. Where a project calls for specific material grades, pressure vessel certification or ATEX-rated equipment, we build to that standard and ship the full documentation pack.
Twenty-Plus Export Markets
We have shipped to the United States, Canada, Russia, Indonesia, India, Nigeria and Vietnam among others. Crating, export documentation and certificates are handled in-house, which keeps customs surprises to a minimum.
Complete System Responsibility
One supplier, one process guarantee. We take the plant from preliminary screening through to membrane separation, evaporation and brine management, with process, mechanical, electrical and controls engineering handled internally.
After the Handover
Spares for everything we install are held in stock. Remote telemetry is available on most systems, and our service engineers commission, train your operators and turn out for emergencies.
Getting Started
Send us a water analysis and your production profile and we will tell you honestly what the process should look like and roughly what it costs to build and run. Reach our engineering team on WhatsApp: +86 13631765076 or via hkbhp.com.
WhatsApp: +86 13631765076
Customer FAQs
What is leachate zero liquid discharge?
It is a train that removes all the water from leachate reject as clean distillate and drops the salts as a solid cake, so no liquid leaves the site. It is used where there is no receiving water or the discharge consent forbids liquid release.
Why concentrate the reject before evaporation?
Evaporation is the costly energy step, so thickening the reject with membranes first roughly halves the volume the evaporator must boil. That cuts the steam or power bill proportionally and makes ZLD affordable at smaller scales.
What is MVR and why use it?
Mechanical vapour recompression compresses the evaporator own vapour to reuse its latent heat, far more efficient than direct steam heating. It lets a ZLD train run on electricity without a steam header, which suited this mountain site.
What happens to the salt cake?
It is characterized and sent to an appropriate disposal facility rather than a general landfill. The cake mass is tracked so the operator can confirm the water loop is truly closing with zero liquid leaving. The operating detail behind this sits in landfill leachate treatment.
Readers planning similar projects often also read Baihuipu Delivers Brackish Water RO System to Industrial Park system and Baihuipu Treats Boiler Chemical Cleaning Wastewater On Site system for the process detail behind these systems.
