褐煤、烟煤、无烟煤均可被风化,成为风化煤。煤的风化作用是指在大气、水、温度变化和生物活动等外界因素作用下,使煤逐渐崩解破碎成碎块和细粒。煤的风化作用分为物理风化、化学风化和生物风化三种类型。 Lignite, bituminous coal, anthracite coal can be weathered, become weathered coal. The weathering effect of coal refers to the gradual disintegration and disintegration of coal into pieces and fine grains under the action of external factors such as atmosphere, water, temperature changes and biological activities. Coal weathering is divided into physical weathering, chemical weathering and biological weathering three types.