Rotary Drum Dryer for Lignite with Low-Oxygen Environment High Moisture Reduction and Precise Temperature Control

Rotary drum dryer for lignite

1.Product Introduction

• A Rotary Drum Dryer for lignite is specialized thermal equipment designed to dry brown coal, which naturally has high moisture (typically 35%–50%) and low calorific value. Because lignite is highly volatile and prone to spontaneous combustion when heated, this dryer uses precise temperature controls and low-oxygen environments to safely reduce moisture to under 10%–15%, significantly upgrading its heating value and stability.

2.Application

• Power Generation: Upgrading raw lignite into high-quality fuel for thermal power plants, reducing coal consumption and emissions.

• Lignite Briquetting: Drying the coal to the optimal moisture level required for pressing into high-density, easily transportable briquettes.

• Coal Gasification & Liquefaction: Preparing dry, uniform feedstocks for chemical conversion processes.

• Long-Distance Transport: Reducing water weight before shipping to significantly lower logistics costs and prevent spontaneous combustion during transport.

3.Working Principle

The dryer operates on a continuous, tightly sealed heat exchange mechanism:

• Feeding: Wet coal is continuously fed into the slightly inclined, rotating cylindrical drum.

• Cascading & Drying: Internal lifting flights and chains lift the coal and shower it through the hot air stream. This constant movement breaks up clumps and creates a uniform curtain of coal, allowing rapid heat transfer and moisture evaporation.

• Discharge & Safety Control: The dried coal slides to the lower discharge end. An induced draft fan pulls the moist air out through a cyclone and baghouse filter to capture fine coal dust. Safety systems, such as inert gas injection or explosion relief valves, are often integrated to manage combustible coal dust safely.

4.Technical Specifications