Biomass solid fuel
A biomass solid fuel having low self-heating. In the biomass solid fuel, mutual bonding or adhesion between pulverized biomass particles is maintained and the biomass solid fuel has a maximum reaching temperature of less than 200° C. in a self-heating property test based on the “UNITED NATIONS Recommendations on the TRANSPORT OF DANGEROUS GOODS: Manual of Test and Criteria: 5 th revised Edition: Test method for Self-heating substances”.
1. A biomass solid fuel which is obtained by molding a pulverized biomass into unheated biomass blocks and heating the unheated biomass blocks at a temperature of 230° C. to 270° C., wherein mutual bonding or adhesion between pulverized biomass particles is maintained after immersion in water, and which has a maximum reaching temperature of less than 200° C. in a self-heating property test in which the biomass solid fuel is charged into a sample container placed in an oven at a temperature of 140° C., and the temperature of the biomass solid fuel is continually measured for 24 hours during which the highest temperature thereof is defined as the maximum reaching temperature, and wherein at least one condition selected from the group consisting of the following conditions, (d1) and (e1) is satisfied:
condition (d1): a raw material of the pulverized biomass comprises Pinus radiata , and the biomass solid fuel has a volatile matter (dry ash free basis) of 77.5 wt % or more; and
condition (e1): a raw material of the pulverized biomass comprises a mixture of larch, spruce and birch, and the biomass solid fuel has a volatile matter (dry ash free basis) of 71.0 wt % or more.
2. The biomass solid fuel according to claim 1 , having a fuel ratio of 0.10 to 0.45.
3. The biomass solid fuel according to claim 1 , wherein at least one condition selected from the group consisting of the conditions, (d2) and (e2) is satisfied:
condition (d2): the condition (d1) is satisfied, and the biomass solid fuel has a fuel ratio of 0.295 or less; and
condition (e2): the condition (e1) is satisfied, and the biomass solid fuel has a fuel ratio of 0.405 or less.
4. The biomass solid fuel according to claim 1 , wherein at least one condition selected from the group consisting of the following conditions (d3) and (e3) is satisfied:
condition (d3): the condition (d1) is satisfied, and mechanical durability DU after immersion in water of the biomass solid fuel is 95.5 or more; and
condition (e3): the condition (e1) is satisfied, and mechanical durability DU after immersion in water of the biomass solid fuel is 97.8 or more.
5. The biomass solid fuel according to claim 1 , wherein the following condition (d4) is satisfied:
condition (d4): the condition (d1) is satisfied, and the unheated biomass blocks are heated at a temperature of 250° C. to 270° C.
6. The biomass solid fuel according to claim 4 , wherein at least one condition selected from the group consisting of the following conditions (d5) and (e5) is satisfied:
condition (d5): the condition (d3) is satisfied, and mechanical durability DU after immersion in water of the biomass solid fuel is 96.6 or less; and
condition (e5): the condition (e3) is satisfied, and mechanical durability DU after immersion in water of the biomass solid fuel is 98.7 or less.