Shell block-type graphite heat exchangers
Shell block-type heat exchanging apparatus are used as coolers, boilers, condensers and evaporators. The main working elements of such type of apparatus are cylindrical and rectangular blocks. Two sets of non intersecting channels are drilled in the block: vertical parallel and horizontal axes of a heat exchanger. The aggressive medium is supplied via vertical channels and the inert atmosphere is supplied via horizontal channels. The apparatus is assembled from sever alidentical blocks which are closed from above and below with graphite timing covers. The graphite part of the apparatus is put inside the metal casing which consists of separate shells. The block is sealed with expanded polytetrafluoroethylene packing and the shell flanges are sealed with acid pro of paronite or graphite gaskets. Heatings teamissupplied in to the casing through a connecting piece and circulates along horizontal channels. As the steam cools down condensate is discharged through the bottom connecting piece. The liquid is completely removed from the housing void via the connecting piece in the bottom cast iron plate of the apparatus.
Advantages of using block-type shell graphite heat exchangers compared to shell-and- tube graphite heat exchangers:
1) Some media cause significant expansion of АТМ-1Т tubes dramatically reducing the mechanical strength of shell-and-tube apparatus despite the external stability of the design which may result in the breakdown of the apparatus before the considered end of its operating life.
2) Taking into account Russian chemical production specifics, block-type HG-BS apparatus have become mostly common due to simple maintenance and long operating life.
3) The arrangement of blocks in HG-BS type apparatus makes it suitable for many processes related to heating, cooling, evaporation, condensation, etc.
4) The engineering design of HG-BS type apparatus implies high safety against hydraulic and mechanical impacts compared to shell-and-tube apparatus.
5) Varying area of heat exchange: between 5.5 and 540 m2
6) Engineering materials and high molecular resins applied in the production of block-type apparatus allow them to operate under pressure of 1МPа.