NOVELTY - A biomass molded coal comprising coal and straw is composed of 1 part by weight (pts. wt.) of pulverized coal, 0.4-1.5 pts. wt. modified biological straw powder, 0.5 pts. wt. active sludge and 0.1-0.2 pts. wt. modified magnesium smelting slag.    USE - As biomass molded coal and process for preparation of biomass molded coal (all claimed).    ADVANTAGE - The biomass molded coal improves combustion use performance of powder coal and poor quality coal, reduces fly ash and sulfur, saves energy, reduces environmental pollution, at the same time, agricultural plant straw replaces part of fossil energy and reduces carbon emission, and processed waste and industrial waste residue acts as adhesive and sulfur fixing agent, which can effectively reduce carbon discharge, discharge of water treatment waste, and industrial waste residue to environment; which solves problems associated with coal such as low heat value and high sulfur content, causing waste and environment pollution. The plant straw and forestry is treated by hot alkali hydrolysis treatment, and hydrolyzed product of plant straw has sugar, pectin, tannin and cellulose, lignin, which are not decomposed, and increase biomass molded coal bonding effect, and improve intensity of molded coal. Further heat value of lignin is high, which increases heat value of biomass molded coal. Use of sludge reduces process waste. The sludge itself is organic, has certain thermal value, and adhesive property, thus when used as molded coal bonding agent, it reduces residual carbon in ash, improves intensity of molded coal, and solves problem that sludge accumulation cannot be processed. The modified magnesium smelting slag acts as bonding agent and sulfur fixing agent, and avoids use of expensive inorganic reagents.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for producing biomass molded coal involving: crushing and screening coal to obtain coal particles having grain diameter of less than 3 mm, and keeping for further use; preparation of modified biological straw powder that involves taking biological straw powder having particle size of less than 2 mm, with stirring and heating in reactor, adding to straw powder by weight mass fraction of 3-4 times 1-2% NaOH solution, heating to 75-85 degrees C under stirring state, after keeping temperature for 1.5-2.5 hours, taking out straw powder and keeping for further use; preparation of modified magnesium smelting slag that involves taking magnesium smelting slag in reaction vessel, adding 8-12% dilute hydrochloric acid solution with stirring in magnesium smelting slag, in 1-1.5 times mass percentage of weight of magnesium smelting slag, to form uniform paste, taking out and keeping for further use; molding of materials that involves mixing 1 pts. wt. of pulverized coal, 0.4-1.5 pts. wt. modified biological straw powder, 0.5 pts. wt. active sludge and 0.1-0.2 pts. wt. modified magnesium smelting slag uniformly, putting into press-molding apparatus, and drying obtained biomass molded coal.    DESCRIPTION OF DRAWING(S) - The figure shows process for preparation of the biomass molded coal. Drawing includes non-English language text.