CE Certified Zero Liquid Discharge (ZLD) Systems: Engineering & Manufacturing

Precision-engineered membrane concentration, high-recovery DTRO/STRO, and advanced evaporation crystallizer architectures compliant with EN ISO 12100 & EU Machinery Directive standards.

Primary Solutions

High-Yield Water Treatment & Desalination Skids

Pre-commissioned, containerized modular units engineered for zero liquid discharge, produced water extraction, and ultrapure distribution.

Zero Liquid Discharge Architecture

Macro-Industry Solutions & Global Procurement Landscape

Addressing hypersaline brine mitigation, mineral circularity, and stringent ESG criteria across heavy chemical, semiconductor, and energy sectors.

Severe Brine Concentration via DTRO & STRO

Traditional spiral-wound reverse osmosis elements experience rapid colloidal blinding and organic scaling at total dissolved solids (TDS) exceeding 45,000 ppm. Our disc tube (DTRO) and spacer tube (STRO) modules utilize open-channel geometries operating at osmotic pressures up to 120-160 bar, safely taking wastewater to 100,000–140,000 ppm TDS without premature membrane destruction.

Thermal Volume Reduction (MVR & TVR)

By employing Mechanical Vapor Recompression (MVR) falling film evaporators paired with forced-circulation crystallizers, the system cuts electrical and steam consumption up to 60% compared to single-effect steam thermal evaporators. Condensed steam is routed back to process loops as high-purity distillate (<10 µS/cm), while salt slurries are dewatered via automated centrifuges.

Circular Economy & Salt Valorization

Modern zero liquid discharge systems are transitioning from disposal-oriented waste streams into high-efficiency chemical synthesis setups. Fractional crystallization systems divide mixed sodium chloride and sodium sulfate liquors, transforming mixed sludge liabilities into commercial-grade industrial byproducts suitable for reuse or local resale.

Engineering Workflow

Complete Process Flow: From Raw Effluent to Solid Crystals

A multi-barrier train mitigating fouling, mineral precipitation, and volatile organic carry-over across 4 standardized processing steps.

PHASE 01

Chemical Softening & Clarification

Dosing caustic soda, soda ash, and coagulants removes total hardness (Ca²⁺, Mg²⁺), barium, strontium, and silica to prevent scaling in downstream thermal stages.

PHASE 02

Ultrafiltration & Organic Scrubbing

Hollow fiber UF modules strip suspended solids (SDI < 3), while specialized macroporous resin beds extract persistent chemical oxygen demand (COD) and free emulsified oils.

PHASE 03

High-Pressure DTRO Concentration

Open-channel DTRO racks step up osmotic pressures incrementally to 90–120 bar, reclaiming 70–85% of incoming water volume as high-value permeate for reuse.

PHASE 04

MVR Crystallization & Dewatering

The remaining supersaturated mother liquor reaches the forced circulation evaporator, precipitating solid crystal cakes dewatered to <10% moisture content via pusher centrifuges.

Global Delivery

CE Conformity, Localization Support & Robust Compliance

Full traceability conforming to EU Directives, ASME Boiler and Pressure Vessel Code, and regional environmental standards worldwide.

CE Machinery Directive

Full adherence to Directive 2006/42/EC and Low Voltage Directive 2014/35/EU, ensuring electrical panels, pump interlocks, and thermal enclosures pass exhaustive third-party inspection.

Pressure Equipment (PED)

Manufactured under PED 2014/68/EU guidelines, utilizing titanium Gr. 2, duplex 2205, and super duplex 2507 alloys certified with EN 10204 3.1 material test certs.

SCADA & Remote Monitoring

Engineered with Siemens S7-1500 or Allen-Bradley PLCs featuring integrated IoT gateways for 24/7 cloud diagnostics, predictive membrane fouling analytics, and remote parameter tuning.

Turnkey Site Deployment

Skid-mounted containerized architecture reduces field civil works by 70%. Pre-wired, hydro-tested in factory test bays (FAT), requiring only piping hookups upon arrival.

38+
Invention & Utility Patents
99.5%
Max Water Recovery Rate
15 Days
Average Skid Commissioning
ISO & CE
Third-Party Certified
Procurement Guide

Frequently Asked Questions (FAQ)

Essential technical points for plant managers, EPC engineers, and international procurement teams evaluating ZLD capital expenditures.

How does CE certification influence ZLD system safety and global customs clearance?

CE certification validates full conformity to European Directives, specifically Directive 2006/42/EC for mechanical assembly safety and 2014/68/EU for pressurized vessels. For global engineering procurement, CE mark guarantees high-pressure pipe headers, electrical controls, and emergency blowdown routines adhere to verified hazard analyses, mitigating compliance bottlenecks at border customs and accelerating insurance sign-offs.

What is the typical OPEX comparison between direct thermal evaporation and DTRO-assisted ZLD?

Directly sending high-salinity wastewater (30,000–50,000 ppm TDS) into thermal evaporators results in massive steam or electricity demand (typically 40–70 kWh/m³ equivalent). Incorporating DTRO/STRO membrane systems to pre-concentrate brine up to 100,000–140,000 ppm TDS recovers up to 75% of clear water at membrane energy efficiencies (5–9 kWh/m³), shrinking the thermal evaporator footprint and cutting lifecycle OPEX by 45% to 65%.

How does the system prevent silica scaling in membrane modules?

Silica scaling is handled through a two-fold engineering defense: upstream chemical magnesium oxide/lime precipitation running at high pH (>10.5) to clear dissolved silica down to <20 ppm, combined with specialized antiscalant chemistries and open-channel disc-tube hydraulic paths that maintain high shear velocities across the membrane surface to inhibit crystal seeding.

What warranty and lifecycle services are available for overseas deliveries?

Every system includes a 12-to-24-month comprehensive mechanical performance warranty. Tongjie maintains localized dispatch support, remote SCADA connectivity for live monitoring, regular membrane cleaning protocol delivery, and rapid replacement component staging across key trade corridors.
Targeted Equipment Portfolio

Specialized Heavy Industry & Oilfield Water Systems

Engineered packages built for oilfield fracturing flowback, high-purity EDI demineralization, and custom OEM manufacturing.