10 tons double-stage reverse osmosis equipment in industrial waste disposal and resource utilization projects

Project Overview

This project focuses on industrial waste disposal and resource utilization, with an annual treatment capacity of 50,000 tons. The production plant uses inorganic acids as decomposers and a selective leaching process to:

• Separate useful elements from waste residues

• Produce lithium carbonate from lithium elements

• Manufacture high-molecular cryolite and magnesium sulfate heptahydrate from chlorine, aluminum, sodium, and magnesium elements

  Recover high-purity carbon powder and by-produce precipitated silica

Key requirements: Effective control and recycling of waste residues, wastewater, and exhaust gas with minimal or compliant discharge.

Water Source and Quality

Raw Water (Tap Water) Parameters:

• Color: <10

• Turbidity: 0.5 NTU

• Visible matter: None

• pH: 7.41

• Total Fe/Mn/Cu/Zn: <0.04 mg/L

• Chloride: 37.4 mg/L

• Sulfate: 28.4 mg/L

• Dissolved Solids: 447 mg/L

• Total Hardness (as CaCO₃): 319 mg/L

• Oxygen Consumption: 0.8 mg/L

• Volatile Phenol: 0.002 mg/L

Water Quality Requirements

• System design: 1 unit in operation, 1 unit standby

• Stage 1 RO: Max. 40 m³/h, Min. 20 m³/h (excess water for boiler make-up)

• Stage 2 RO: Max. 20 m³/h, Min. 10 m³/h (for production process water)

Solution Overview

The industrial demineralized water treatment process consists of three parts:

Treatment System

Raw Water → Raw Water Heater → Sand Filter → Carbon Filter  
→ Removal of suspended solids, turbidity, colloids, etc.

Stage 1 RO Product Water Tank → Stage 2 RO → Stage 2 Product Water Tank  
→ Water Supply Pump → Process Points

Reverse Osmosis System

1. Stage 1 RO:

• 30 membrane elements per set (6 pressure vessels with 5 elements each)

• Arrangement: 2:2

• Designed output: 20 m³/h

2. Stage 2 RO:

• Arrangement: 1:1

• Designed output: 10 m³/h

Process Flowchart

Pressurized Raw Water → Raw Water Tank → Raw Water Pump → Plate Heat Exchanger →  
Multi-media Filter → Activated Carbon Filter → Pipeline Mixer (Reducer/Scale Inhibitor) →  
Stage 1 RO Security Filter → Stage 1 RO High-pressure Pump → Stage 1 RO Unit →  
Stage 1 RO Product Tank → Stage 2 RO Booster Pump → Pipeline Mixer (Inter-stage Alkali) →  
Stage 2 RO Security Filter → Stage 2 RO High-pressure Pump → Stage 2 RO Unit →  
Stage 2 RO Product Tank (Demineralized Water Tank) → Demineralized Water Supply Pump → Usage Points  

Stage 1 RO Concentrate → Concentrate Collection Tank → Pretreatment System Flush → Discharge