Applications
Heaters, coolers, interchangers, condensers and evaporators for corrosive media, especially in the treatment of:
- Hydrochloric acid (HCl)
- Sulfuric acid (H2 SO4)
- Hydrofluoric acid (HF)
- Mixed Acids (HNO3/HF)
- Phosphoric acid (H3 PO4/P2O5)
- Other organic and inorganic media
Standard design
The graphite plate heat exchanger consists of a pack of corrugated graphite plates with portholes for the passage of the two fluids between which heat transfer will take place. The plate pack is assembled between a carbon steel fixed frame plate and movable pressure plate and compressed by tightening bolts. The difference in coefficients of expansion of carbon steel and graphite is compensated for by means of helical springs.
The plates are fitted with a film type PTFE gasket of 0,2 mm thickness after tightening, which seals the inter-plate channel and directs the fluids into alternate channels. The number of plates is determined by the flow rate, pressure drop and temperature program. The plate corrugations promote fluid turbulence and minimise fouling.
The frame plate and pressure plates are suspended from an upper carrying bar and located by a lower guiding bar, both of which are fixed to a support column. Connections are located in the frame plate or, if either or both fluids make more than a single pass within the unit, in the frame and pressure plates.
The frame and pressure plates are protected from the corrosive media by means of a PTFE lining.
Typical capacities
Max flow rate of 250 m3/h, depending on media, permitted pressure drop and temperature program.
- Plate types: S1, M10-G, S10, S15.
- Frame types: One standard frame available that can be modified to higher design pressures.
Standard materials
- Plates: F100, NS1/NS2
F100
DIABON® F100 plates are suitable for operations where fouling can be a problem as well as for oxidising environments.
The DIABON® F100 plates are pressure moulded with a herringbone plate pattern on both sides which gives rise to very efficient turbulence. Erosion risk is minimised due to a hard plate surface. The PVDF encapsulating of the graphite grains yields plates with a very smooth, non-porous and anti-adhesive surface and provides more resistance against oxidising media.
NS1/NS2
NS1 and NS2 grade plates are preferred for 2 phase applications and/or duties with higher variations in temperature.
The NS1 and NS2 plate pattern is machined from blocks of resin impregnated material. The plates are flat on one side and have a fin-plate pattern on the side facing the pressure plate. The plate pattern has very few contact points which makes the plates more suitable for fluids containing fibres. The resin impregnated graphite in these plates is less sensitive to thermal fatigue and can handle high temperature differences. These plates are not suitable for oxidising media.
Technical data
