NOVELTY - The molded coal produced from emission recycled by an industrial boiler and regulating large-heat coal (4000-6000 kilocalories), medium-heat coal (3000-4000 kilocalories) and heat-insulating coal (2000-3000 kilocalories), is claimed. The large-heat coal comprises emission recycled by an industrial boiler (80-90 parts by weight (pbw)), clay (2-5 pbw), a desulfurizing agent, a waterproofing agent (2-4 pbw), auxiliary material (3-5 pbw) (comprising coal slime, anthracite, coke powder, mixed coal, pulverized fuel ash, plant straws, furfuraldehyde and clinker etc.) and water (1-3 pbw).    USE - Used as molded coal.    ADVANTAGE - The molded coal has improved stability and quality with reduced energy consumption.    DETAILED DESCRIPTION - The molded coal produced from emission recycled by an industrial boiler and regulating large-heat coal (4000-6000 kilocalories), medium-heat coal (3000-4000 kilocalories) and heat-insulating coal (2000-3000 kilocalories), is claimed. The large-heat coal comprises emission recycled by an industrial boiler (80-90 parts by weight (pbw)), clay (2-5 pbw), a desulfurizing agent, a waterproofing agent (2-4 pbw), auxiliary material (3-5 pbw) (comprising coal slime, anthracite, coke powder, mixed coal, pulverized fuel ash, plant straws, furfuraldehyde and clinker etc.) and water (1-3 pbw). The medium-heat coal comprises emission recycled by an industrial boiler (60-80 pbw), clay (5-10 pbw), a desulfurizing agent (3-5 pbw), a waterproofing agent (3-5 pbw), other auxiliary material (10-25 pbw) (comprising coal slime, anthracite, coke powder, mixed coal, pulverized fuel ash, plant straws, furfuraldehyde and clinker etc.) and water (1-3 pbw). The heat-insulating coal comprises emission recycled by an industrial boiler (40-60 pbw), clay (5-13 pbw), a desulfurizing agent (3-5 pbw), a waterproofing agent (3-5 pbw), other auxiliary material (20-45 pbw) (comprising coal slime, anthracite, coke powder, mixed coal, pulverized fuel ash, plant straws, furfuraldehyde and clinker etc.) and water (1-3 pbw). The desulfurizing agent is lime powder, is present in 3-5% of the large-heat coal, the medium-heat coal and the heat-insulating coal. The waterproofing agent is pulverized fuel ash, is present in 2-4% of the large-heat coal, 3-5% of the medium-heat coal and 3-5% of the heat-insulating coal. The emission recycled by an industrial boiler is present in 80-90% of the large-heat coal, 50-80% of the medium-heat coal and 40-60% of the heat-insulating coal. The clay is present in 2-5% of the large-heat coal, 5-10% of the medium-heat coal and 5-13% of the heat-insulating coal. The auxiliary material comprises coal slime, anthracite, coke powder, mixed coal, pulverized fuel ash, plant straws, furfuraldehyde and clinker etc., where the auxiliary material is present in 3-5% of the large-heat coal, 10-25% of the medium-heat coal and 20-45% of the heat-insulating coal. The content of water in the coal is 1-3%. The emission recycled by an industrial boiler has a bonding action. An INDEPENDENT CLAIM is included for a method of preparing molded coal produced from emission recycled by an industrial boiler.