An economic study of the present feedwater treatment system at the V.P.I. power plant

Abstract

The purpose of this thesis was to study the economical aspects of the present boiler feed water treating system at the VPI Power Plant. In carrying out the investigation, two testing periods were conducted, each lasting for four weeks and the first period was preliminary in nature.

The experimental results revealed that the cost on caustic soda(NaOH) could be reduced by improving the performance of the mechanical degasifier; the cost on neutralizing amines (Nalco 35) was insufficient to insure maximum protection against corrosion; the cost of blowdown was too high; and the cost on sodium orthophosphate and ligin derivatives (Nalco 728) could be reduced.

Recommendations are made based on the test results and plan for future expansion of plant capacity. It is recommended that the degasifier be overhauled; the optimum blowdown quantity be studied; the Boiler No. 5 be inspected for leaks; a better method found for feeding Nalco 35; and the installation of an automatic pH meter and a continuous conductivity recorder for the main condensate return line.

The average cost for feedwater treatment at the VPl Power Plant from March 25 to April 20, 1958, was $ 1.334 per thousand gallons of New River water demineralized.