Feedwater Treatment for Advanced Propulsion Steamships. Evaluation of the Application of Feedwater/Condensate Polishing and/or Filtration to Steam Propelled Ships

摘要

This report presents the results of a study which was designed to evaluate the feasibility of polishing feedwater to a degree of purity considered acceptable for proposed steam turbine propulsion plants operating with a throttle pressure of 2400 p.s.i. The polishing technique used was precoat demineralization/filtration. Significant findings and conclusions were: (a) A high degree of demineralization can be achieved (down to around 40 p.p.b. t.d.s.). (b) Efficacy of demineralization and filtration depends upon restoration of the polisher to a completely clean condition at the end of each service run; this condition was not always satisfied. (c) Further development work is required on the combination of technologies involved to overcome operational problems. Significant recommendations are: (a) Full automation of the system. (b) Mechanical filters to be included in the feed stream. (c) More extensive analytical instrumentation than employed in the study. (d) Provision to be made for emergency boiler water treatment in the event of gross contamination.