Patent Number: 
Section: claims

1. A porous cooling block for cooling corium, comprising:a base part comprising a top surface, a bottom surface, and a plurality of side surfaces connecting the top surface and the bottom surface to each other, and including a plurality of pores; anda channel part defining an opening on at least one surface among the top surface, the bottom surface and the plurality of side surfaces, and communicating with the plurality of pores,wherein the channel part comprises:a first channel formed to extend in an inward direction from one surface of either the top surface or the bottom surface of the base part; anda second channel formed to pass through two side surfaces facing away from each other among the plurality of side surfaces of the base part, and communicating with the first channel,wherein the first channel and the second channel provide a flow path of cooling-water in the base part. 2. The porous cooling block for cooling corium according to claim 1, whereinthe second channel is provided in plurality in a way to pass through two respective side surfaces in one direction and another direction, andthe plurality of the second channels communicate with one another by crossing in the base part. 3. The porous cooling block for cooling corium according to claim 1, the first channel comprising,a first hole defining an opening on a surface of either the top surface and the bottom surface; anda first flow path connected to the first hole to form a path toward inside of the base part. 4. The porous cooling block for cooling corium according to claim 1, the second channel comprising,a pair of second holes defining an opening to the two side surfaces; anda second flow path connecting the second holes to form a path inside of the base part and communicating with the first channel. 5. The porous cooling block for cooling corium according to claim 1, wherein an average cross-sectional area of the first channel is smaller than that of the second channel and larger than that of the plurality of pores. 6. A corium cooling apparatus, comprising:a plurality of porous cooling blocks arranged to align with one direction and another direction crossing the one direction to form a plane, wherein at least one of the plurality of porous cooling blocks is a porous cooling block of claim 1;a sacrificial part received safely on the plurality of porous cooling block and covering an exposed upper surface of the porous cooling blocks; anda cooling-water supply unit for supplying cooling-water to the porous cooling blocks. 7. The corium cooling apparatus according to claim 6, wherein each of the plurality of porous cooling blocks is arranged to be able to separate from an aligned and arranged region. 8. The corium cooling apparatus according to claim 6, the sacrificial part comprising,a separation member covering the porous cooling block; anda sacrificial member received safely on the separation member, andat least one member of the separation member and the sacrificial member is provided being divided in plurality and aligned and stacked in order on the plane. 9. The corium cooling apparatus according to claim 8, wherein, on a side surface of the porous cooling block, a side surface separation member is arranged which is arranged on the most outside edge of a width formed by the plane and covering at least a partial region of the side surface of the porous cooling block. 10. The corium cooling apparatus according to claim 8, wherein the separation member provides a sealed space for sealing the porous cooling block. 11. The corium cooling apparatus according to claim 6, the cooling-water supply unit comprising,a cooling-water storage storing cooling-water supplied to the porous cooling block; anda cooling-water passing pipe whose one end is connected to the cooling-water storage and another end communicates with the porous cooling block.