Heat Pipe Steam Condenser

Heat Pipe Steam Condenser

Project Title

Design & Development of a 300 kg/hr Heat Pipe Steam Condenser

(B YH 92 013 RD 48)

Objective

To gain experience in the indigenous manufacture of heat pipes and heat pipe steam condenser operation

Project Description

A prototype 300 kg/hr heat pipe steam condenser was indigenously developed and successfully tested at BHEL/R&D steam generator facility. The 1.5 m long 25.4 mm diameter integral high-fin aluminum tubes were used to manufacture the heat pipes. The fin height is 11 mm and the fin density is 350 fins/m.  Acetone is the working fluid. A four layer #100 and #200 composite stainless steel wire screen served as a wick. The unit was fabricated with 150 Nos. of heat pipes laid in a staggered arrangement. The airside heat transfer area for the unit is 150 m². Each heat pipe is capable of handling 1000 W. The unfinned evaporator sections of the heat pipe, 0.5m long, were located in a rectangular steam plenum, which was continuously evacuated by water-ring vacuum pump. The finned condenser sections 1 m long inclined to the vertical by 15⁰ are exposed to a blast of cold air circulated by an ID fan mounted on the top of the unit.

  

Evacuation and Filling of Heat Pipe Steam Condenser in Progress  

    The equipment was instrumented for measuring the vacuum level in the steam plenum, the steam temperature and condensate flow rate. The steam temperature was maintained at about 60 ⁰C. The steam plenum is connected to the 600 kg/hr oil fired steam generator available at BHEL/R&D. A glass level-indicator is fitted to the plenum to monitor the condensate level. The indicator also helped to ensure that the heat pipe evaporator ends are not flooded with the condensate thereby reducing the effective evaporator length.

Heat Pipe Condenser under Testing

  The prototype heat pipe condenser was continuously operated and a condensate rate of 300 kg/hr was measured. With the successful testing of a laboratory scale steam-condensing unit using heat pipes, several significant applications for dry condensing systems can be foreseen. While the main thrust area is the clean coal technology with dry type large steam condensers using carbon steel/ammonia heat pipes for economical production and operation in water scarce zones, the product will find application in many process industries.