I. System Function

This NMP recovery system utilizes the miscibility of NMP and water to treat and recover exhaust gases discharged from the coating machine. The equipment operates fully automatically to ensure the stability and safety of the system. It adopts a three-stage spray absorption design, with tail gas emissions far below the national discharge standards. The system is composed of ventilation ducts, recovery towers, pump units, blowers, NMP liquid storage tanks, and a control system. Featuring high recovery efficiency, low operating costs, compact footprint, attractive appearance, and superior performance, it is suitable for various environments and installation configurations. It is particularly applicable to the coating processes of multiple lithium battery production lines.

II. System Configuration

1. Air Treatment Capacity: 4000 m³/h
Compliance Standard: GB 30484-2013 Emission Standard of Pollutants for Battery Industry – Total Non-Methane Hydrocarbons.

2. Main Unit Color: SUS gray.

3. Functional Modules Overview:

4. Delivery List:

5. Main Components of the 4000 Air Volume NMP Recovery System:

IV. Design Basis and Reference Standards

1.Conforms to applicable national, industry, and local regulations, as well as client requirements. Treated emissions meet all legal and contractual requirements.

2.Uses energy-efficient and user-friendly processing methods to achieve low energy consumption, minimal investment, compact footprint, and convenient operation.

3.All equipment, components, and electrical parts are sourced from well-known and reliable brands.

4.No secondary pollution is generated during construction or operation phases.

V. Technical Parameters

VI. Process Flow

1. Process Diagram: (For reference only)

2. Installation Render: (For reference only)

VII. Working Principle of the NMP Recovery Tower

1. Pure water is used to absorb and recover NMP from exhaust gases. Waste gas enters from the bottom of the tower and passes through the gas adsorption unit, where NMP dissolves into water and water vapor. The treated exhaust then passes through a gas-liquid separator and a top rinsing unit to ensure complete NMP absorption. Due to the high temperature of incoming gases, partial water evaporation occurs during the heat exchange process. A circulation pump is used to recirculate the tower liquid, facilitating efficient heat recovery, reducing water waste, and increasing the concentration of recovered NMP liquid. After treatment, the exhaust can be directly released without further purification, achieving near-zero emissions.

2. Tower Structure:
The tower consists of three major zones:

Spray Heat Exchange Zone: Enables rapid mass transfer between NMP-laden gas and water via direct contact. This mixing-based heat exchange method avoids the resistance caused by heat transfer walls and scaling, ensuring efficient energy exchange.

Mass Transfer Separation Zone: Utilizes high-efficiency structured packing for gas-liquid contact, allowing counter-current flow and efficient NMP absorption through a 140Y specific surface area filler.

Demisting Zone (White Smoke Removal):

Lower demister: Droplets collide with demister packing and are collected. Baffle plates create turbulent airflow, allowing droplets to be captured by inertia.

Upper demister: Airflow passes through blades forming a spiral, throwing droplets outward into the overflow groove. Demisting efficiency reaches 90%–99%.

VIII. Control System

1. Electrical Panel Configuration:

2. Control System Description: