Cold Boxes & BAHX
Chart Energy & Chemicals, Inc., is a specialist in the design and manufacture of Brazed Aluminium Heat Exchangers (BAHX), which are Mission Critical for a wide variety of cryogenic processing applications where reliability and thermal performance are paramount. Chart BAHX can be supplied as single units, manifolded assemblies or integrated solutions comprising a complete Cold Box ready for field installation. The Core-in-Kettle® is a further derivative of a BAHX.
Chart's principal BAHX sales, engineering and technical support offices are in Wisconsin, USA and Wolverhampton, England and the Wisconsin facility is also the home of manufacturing. Large assemblies and cold boxes are built in Louisiana, USA, with direct water access, and Changzhou, China.
Principal applications for BAHX include:
- Industrial gas production – air separation, nitrogen liquefaction, helium liquefaction, argon recovery
- Natural gas processing – nitrogen rejection, helium recovery, natural gas liquids (NGL) recovery, ethane recovery
- Petrochemical processing – ammonia purification, hydrogen recovery, propane dehydrogenation, ethylene production
- Natural gas liquefaction (LNG) – peak shaving, small and mid-scale liquefaction plants, floating LNG, vehicle fuelling
Advantages of Using Chart Heat Exchangers
Lower Operating Temperatures
Chart E&C heat exchangers are well suited for the low temperature requirements of cryogenic applications since the 100% aluminum construction can withstand temperatures as low as -269°C and very high pressures (i.e. 1750 psig/120 bar g or higher).
Lower Capital Costs
Six to ten times higher high surface area than that of a comparable shell-and-tube heat exchanger. This characteristic, coupled with the enhanced heat transfer performance of plate-fin construction, produces as much as twenty times greater heat transfer performance (UA) than shell-and-tube exchangers of equal size. This higher efficiency can correlate to a Chart E&C heat exchanger costing approximately 25-50% less and weighing 95% less than a stainless steel shell-and-tube exchanger.
Flexible Design
Chart Energy & Chemicals' heat exchangers can be designed with more than ten streams and a nearly unlimited number of configurations by varying parameters such as block size and shape, fin type, layer stacking arrangement and flow scheme.
Lower Installation and Operating Costs
Chart E&C's multi-stream design can result in significant cost reduction in; Engineering, Insulation, Support systems, Installation, Testing, Documentation, Transportation, Plot plan requirements Additionally, Chart E&C's heat exchangers allow temperature approaches that result in lower compressor horsepower requirements and lower plant operating costs.
Chart Energy & Chemicals' Heat Transfer Fins
Chart E&C's design and engineering teams constantly challenge the variables in heat exchanger fin design, analysis and testing. Heat transfer fins are experimentally tested for both heat transfer and pressure drop performance and cover a wide range of characteristics. The company has developed improved heat transfer and fluid flow performance correlations for both single-phase and two-phase fluids.
Replacement Service
Chart offers complete flange to flange replacement BAHX units regardless of OEM. As well as ensuring that replacement units meets all current applicable design standards and best engineering practice Chart will match the thermal and hydraulic performance, pipe centres and support positions of the original items, as far as practicable. This helps ensure that replacement units fit seamlessly into the plant and minimises the amount of ancillary work required for installation.
If required, a replacement Chart BAHX can often be used to increase the overall heat exchanger performance, for example with de-bottlenecking projects, or as part of a technology upgrade, for example an industrial gas plant replacing reversing heat exchanger technology with molecular sieve technology.