SLIDE 4 PRAXEIDOS S.r.l. Sede Operativa Via Fiume 13 - 20871 Vimercate (Monza Brianza), Sede Legale Via Prina 24 - 20900 Monza (Monza Brianza)
- Tel. Uff. +39 039 5968181 - email – commerciale@praxeidos.com Partita IVA 08511600960 - REA MB-1894076 - WEB - http://www.praxeidos.com/
2018 January
PraxEidos Srl
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GAS RECOVERY UNITS
Solvent Recovery Unit
PraxEidos s has developed the technology to reduce pollution from a number of industrial activities using a cryogenic condensation. New laws and attitudes to enviromental protection are driving down the permissible level of emission of volatil organic compounds (VOC’s). The aim is to reduce the damage that VOC’s cause to human healt and enviroment.Many of these substances are cancinogenic and causephotochemical smog. The neatest and cleanest way to remove VOC’s from exaust gas stream is condensation with liquid nitrogen. The technology from PraxEidos removs VOC’s to meet emission level lower than 20 mg/Nm3 as well as overcoming the limitations of traditional control methods.
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The Need The Thecnology Provided The Benefit
Cryogenic recovery system , designed and supplied by PraxEidos, combines the refrigeration power of liquid nitrogenwith the inerting properties of gas nitrogen resulting in a skid mounted VOC’s control system that is simple to install, economical and effective. Running costs are reduced to a minimum by the ability to reuse the nitrogen to purge and blanket pipe work and tanks. Recovered VOC’s can often be reused directly – something that is more difficult with carbon bed technology and impossible with incinerators and catalytic oxydisers. A responsable approach fowards protecting the enviroment means limiting the emissions of volatile components. One method is the condensation of these components by cooling the exaust stream with liquid nitrogen. As the vapours are cooled, the volatile components condense and than freeze. These solid particles can be trapped leaving a clean stream of gas to vent to the atmosphere. The understanding of the heat transfer mechanism has promoted special heat exchanger geometries which are best suited to be properties of boiling nitrogen and condensation of gases within incondensable vapours. The temperature required to meet acceptable emissin standards
- f the order of tens parts per million (ppm) are typically -100 °C
and lower. The obvious choise of a cooling medium is liquid nitrogen which can provide cooling down to -180 °C. The disign of the heat exchangers poses a special challenge which is beyond the remil of typical heat exchanger design packages. Not only are the temperature outside the normal parameters but the heat transfer relationships have to consider the boiling and gas heating of nitrogen, and the condensation and freezing of multiple volatile components in an incondensable stream. PraxEidos has developed computer design tools to model these heat transfer mechanism and generate valid heat exchanger designs.
