Ingersoll Rand (Ireland)

Abstract Mills are currently increasing chlorine dioxide substitution to 50% and more in the chlorination stage in order to reduce dioxins. Reexamination of the TAPPI Phase II data base indicates that up to, at least 48% chlorine dioxide substitution there is no significant difference in alloy performance as determined in the Phase II evaluation program in bleach plant washer environments. Phase II data on localized corrosion replotted provides new and better guidelines on boundary conditions. Based on the wide range in pH, residual chlorine, temperature and chloride covered in these exposures it appears that the 6%Mo alloys can be expected to perform well except under the most extreme combinations of conditions. General corrosion rates for nickel base alloys in C stage do not exceed 0.2 mpy in the Phase II exposures, as compared to the 0.1-0.9 mpy in acidic D stage and 0.1-2.9 mpy in neutralized D stage environments. New data from the C stage of a short sequence bleach plant indicates that the nickel base alloy, C22, is as resistant in the vapor phase as in the liquor. Actual field experience indicates that the nickel base alloys are useful as washers and piping. In C stage environments too aggressive for 6% Mo alloys, nickel base alloys perform well. The cast C4C and wrought C22 alloy are useful in high intensity mixers handling chlorine. Titanium is the preferred material for high intensity mixers handling the chlorine dioxide used in C stage. In some mills titanium is also used for the chlorine high intensity mixer with an elaborate interlock and alarm system to prevent dry chlorine from reaching the titanium.

ABSTRACT Oil and gas production requires compression of gases involving considerable range of initial inlet and final discharge pressures as well as widely varying volumes. Frequently the applications are further complicated by the gas containing H2S or entrained liquids and equipment space/weight limitations imposed by offshore platform designs or semi-portability due to future relocation plans onshore. The manufacturers of compressors, engines and gas turbines have responded to these requirements with a broad selection of power and compressor machinery to make possible an optimum selection for any given installation.