Method for manufacturing a heat exchange graphite assembly, corresponding assembly and tube bundle heat exchanger comprising the same

A method of manufacturing method a heat exchange graphite assembly for a tube bundle heat exchanger, the heat exchange graphite assembly including a plurality of tubes forming a bundle, a pair of tube sheets provided at opposite ends of the plurality of tubes, each tube sheet having through holes for receiving the plurality of tubes, at least one baffle arranged at an intermediate location of the plurality of tubes, each baffle having openings for passage of the plurality of tubes, the method comprising:

• providing the plurality of tubes, the tube sheets, and the at least one baffle in a graphite material being in a non-impregnated or porous state and having a first porosity value;
• positioning the plurality of tubes, the tube sheets, and the at least one baffle in a porous state, respectively, and in a position that forms a clearance between facing walls of the plurality of tubes and the through holes;
• and
• impregnating the plurality of tubes, the tube sheets, and the at least one baffle with an impregnation material different from cement, to fill the pores of the plurality of tubes, the tube sheets, and the at least one baffle, to thereby transform the graphite material to a second porosity value that is less than the first porosity value, form in the clearance a bonding film with the impregnation material, and attach the plurality of tubes with respect to the tube sheets.

A heat exchange graphite assembly for a tube bundle heat exchanger, the heat exchange graphite assembly comprising:

• a plurality of tubes forming a bundle;
• a pair of tube sheets provided at opposite ends of the plurality of tubes, each tube sheet having through holes for receiving the opposite ends of the plurality of tubes;
• and
• at least one baffle, arranged at an intermediate location of the plurality of tubes, each baffle having openings for passage of the plurality of tubes,
• wherein:
• the plurality of tubes, the tube sheets, and the at least one baffle are formed from a graphite material at least partly filled with an impregnation material that is different from a cement, and
• at each opposite end of each tube in the plurality of tubes, a continuous bonding film formed of the impregnation material is interposed between facing walls of each tube and a corresponding through hole to attach a respective end of each tube to a respective tube sheet.

A tube bundle heat exchanger, comprising:

• a heat exchange graphite assembly that includes:
• a plurality of tubes forming a bundle,
• a pair of tube sheets provided at opposite ends of the plurality of tubes, each tube sheet having through holes for receiving the opposite ends of the plurality of tubes,
• at least one baffle, arranged at an intermediate location of the plurality of tubes, each baffle having openings for passage of the plurality of tubes,
• wherein:
• the plurality of tubes, the tube sheets, and the at least one baffle are formed from a graphite material at least partly filled with an impregnation material that is different from a cement, and
• at each opposite end of each tube in the plurality of tubes, a continuous bonding film formed of the impregnation material is interposed between facing walls of each tube and a corresponding through hole to attach a respective end of each tube to a respective tube sheet.
• a shell that surrounds the heat exchange graphite assembly such that the tube sheets are attached to an inner wall of the shell, the shell having:
• a first inlet to facilitate flow a first fluid into the plurality of tubes,
• a first outlet to facilitate flow of the first fluid out of the plurality of tubes,
• a second inlet to facilitate flow of a second fluid into a heat exchange volume formed between the facing walls of the plurality of tubes and the shell, and
• a second outlet to facilitate flow of the second fluid from the heat exchange volume.