Nanofiltration Softening Equipment (NF)

Nanofiltration (NF) Softening Equipment Product Introduction

Nanofiltration (NF) is a pressure-driven membrane separation process that falls between ultrafiltration and reverse osmosis. It gets its name from its nanometer-scale membrane pore size. Its core feature is a high rejection rate for divalent and multivalent ions and large-molecule organic matter, with a lower rejection rate for monovalent ions, enabling selective desalination. Jing'anlan nanofiltration softening equipment uses high-quality spiral-wound nanofiltration membrane elements with an integrated design. It is widely used in water softening, decolorization, drinking water purification, advanced industrial wastewater treatment, and other scenarios. While purifying water, it retains some minerals, and its operating energy consumption is lower than that of reverse osmosis, offering outstanding overall cost-effectiveness.

Working Principle

Under a driving pressure of 0.5–1.5 MPa, raw water passes through the nanofiltration membrane surface. Through the combined effects of sieving and the Donnan effect, it rejects calcium and magnesium ions, sulfates, color-causing substances, antibiotics, pesticide residues, and other components in the water, while water molecules and some monovalent ions (sodium, potassium, etc.) pass through the membrane to become product water. Compared with full desalination by reverse osmosis, the selective separation characteristics of nanofiltration can reduce operating pressure and energy consumption while meeting water quality requirements. It also avoids taste deviation and pipeline corrosion issues caused by excessive desalination of the output water, making it suitable for drinking water softening, reclaimed water reuse, and other scenarios.

Core Technical Advantages

1. Selective separation with highly targeted functionality: It can directionally remove hardness, color, divalent salts, and large-molecule organic matter from water while retaining some mineral ions beneficial to human health. This solves issues such as scaling and yellowing of water quality while avoiding the health and pipeline corrosion risks of pure water, making it suitable for drinking water softening, reclaimed water reuse, and other scenarios.
   

2. Low operating energy consumption and better overall cost: Operating pressure is only 1/2 to 2/3 that of reverse osmosis, the matched pump power is lower, and energy consumption per ton of water is significantly lower than that of reverse osmosis. At the same time, membrane elements have better fouling resistance than reverse osmosis, longer cleaning cycles, and lower chemical and consumable costs, offering outstanding long-term operating cost-effectiveness.
   

3. Stable softening effect that replaces traditional processes: Output water hardness can be stably reduced to below 0.03 mmol/L, thoroughly solving scaling problems in pipelines and equipment. It replaces traditional ion exchange softening processes, requiring no frequent regeneration, no large dosing of acid, alkali, or salt chemicals, and no discharge of regeneration waste liquid, better meeting environmental protection requirements.
   

4. High level of integration for easy installation and maintenance: Skid-mounted modular design, prefabricated and pre-commissioned at the factory, with a short on-site installation period. Equipped with a fully automatic control system, it can automatically complete the entire process of operation, flushing, and cleaning, with a low operating threshold and no need for dedicated staffing.
   

Applicable Industries and Scenarios

• Deep purification of drinking water: removes hardness, color, pesticide residues and organic matter from groundwater and surface water, retains minerals, and improves the taste and safety of drinking water
  

• Boiler makeup water softening: replaces traditional ion exchange processes to achieve deep water softening, prevent boiler scaling, and improve thermal efficiency
  

• Advanced treatment of printing, dyeing and papermaking wastewater: removes effluent color and refractory organic matter to achieve compliant discharge or production reuse
  

• Food and beverage industry: processes such as drinking water softening, sugar liquor concentration, and juice clarification
  

• Municipal and industrial reclaimed water reuse: deeply removes hardness and COD, reducing the risk of corrosion and scaling of pipelines and equipment caused by reused water
  

Selection Guide

The core basis for nanofiltration equipment selection is the feed water quality, permeate water specifications, treatment capacity and application scenario:

• Membrane element selection: selected according to molecular weight cut-off and ion rejection rate, divided into different series such as softening type, decolorization type, and desalination type
  

• System arrangement: according to recovery rate requirements, arrangements such as single-stage single-pass and single-stage two-pass are adopted, with a conventional recovery rate of 60%~80%
  

• Material configuration: water-contact parts can be made of FRP, 304/316 stainless steel, adapting to working conditions with different corrosion levels
  

• Supporting systems: Pretreatment systems, chemical dosing systems, cleaning systems, and online water quality monitoring systems can be optionally configured as needed.
  

Jing'anlan can customize the optimal nanofiltration process solution based on the user's water quality and permeate requirements, balancing treatment effectiveness and operating costs.

Jing'anlan Service Support

• Free water quality testing and process assessment, with customized nanofiltration softening system configuration solutions.
  

• Professional technical team provides on-site installation and commissioning to ensure stable system effluent meeting standards.
  

• Long-term supply of membrane elements, cleaning chemicals, and consumable spare parts.
  

• Can integrate the full process of pretreatment and advanced treatment to provide a one-stop solution.
  

• Provides operation and maintenance training and annual managed services to ensure long-term efficient system operation.