Sulphur Recirculation CUTNOX NextBAT Sulphur Recirculation for reducing corrosion and increasing electrical efficiency in WtE boilers Dr. Sven Andersson Götaverken Miljö AB, Sweden – a Babcock & Wilcox Vølund company GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany SSuullpphhuurr RReecciirrccuullaattiioonn CUTNOX NextBAT Operating principles Full-scale operation Ashes and deposits Emissions Corrosion rates Sulphur Recirculation Sulphur in fuel Ash GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany Sulphur Recirculation CCUUTTNNOOXX NextBAT Operating principles Full-scale installation NO reduction x GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany Sulphur Recirculation CUTNOX NNeexxttBBAATT HCl / SO / NH 2 3 Hg Dioxins NO x Fine particles Energy recovery Sulphur Recirculation CUTNOX™ in combination with SNCR GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany SSuullpphhuurr RReecciirrccuullaattiioonn CUTNOX NextBAT Electricity production in WtE is limited by superheater corrosion Biomass or waste fired boiler GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany SSuullpphhuurr RReecciirrccuullaattiioonn CUTNOX NextBAT Sulphur mass balance Flue gas Sulphur in fuel Ash GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany SSuullpphhuurr RReecciirrccuullaattiioonn CUTNOX NextBAT Sulphur dosage inhibits corrosion Higher SO concentration: 2 Alkali chlorides → alkali sulphates (corrosive) (non corrosive) Sulphur dosage Flue gas Sulphur in fuel Ash GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany SSuullpphhuurr RReecciirrccuullaattiioonn CUTNOX NextBAT Sulphur Recirculation for High Efficiency, Low Corrosion WtE Higher SO concentration: 2 Alkali chlorides → alkali sulphates (corrosive) (non corrosive) Sulphur Recirculation Sulphur in fuel Ash GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany Sulphur Recirculation CUTNOX NextBAT The effect of chromium depletion on chromia forming steels Before After 304L (Fe20Cr10Ni), 5% O + 40%H O, 600°C 2 2 1.4 1.4 Chromate l C formed 1.2 1.2 K )) 22 mm 1.0 cc 1.0 g/g/ mm (( 00..88 n n aiai O3 s gs g 00..66 C ss aa 2 MM 00..44 K 00..22 O (no salt) 2 00..00 4 00 2244 4488 7722 9966 112200 114444 116688 O S EExxppoossuurree ttiimmee ((hh)) 2 K O + H O + KCl 2 2 (Cr,Fe) O Fe O + K CrO + HCl 2 3 2 3 2 4 Pettersson, J., Folkeson, N., Johansson, L.-G., Svensson, J.-E., The Effects of KCl, K SO , and K CO on the High Temperature 2 4 2 3 GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany Corrosion of a 304-Type Austenitic Stainless Steel. Oxidation of Metals, 2011. 76(1): p. 93-109. Sulphur Recirculation CUTNOX NextBAT The effect of chromium depletion on chromia forming steels Before After 304L (Fe20Cr10Ni), 5% O + 40%H O, 600°C 2 2 1.4 11..44 Chromate l C formed 1.2 11..22 K ))) 222 mmm 1.0 ccc 11..00 g/g/g/ mmm ((( 000...888 n n n aiaiai O3 Chromate s gs gs g 000...666 C formed sss aaa 2 MMM 000...444 K 000...222 O (no salt) 2 000...000 4 000 222444 444888 777222 999666 111222000 111444444 111666888 O S EEExxxpppooosssuuurrreee tttiiimmmeee (((hhh))) 2 K O + H O + K CO 2 2 2 3 (Cr,Fe) O Fe O + K CrO + CO 2 3 2 3 2 4 2 Pettersson, J., Folkeson, N., Johansson, L.-G., Svensson, J.-E., The Effects of KCl, K SO , and K CO on the High Temperature 2 4 2 3 GÖTAVERKEN MILJÖ AB –a Babcock & Wilcox Vølundcompany Corrosion of a 304-Type Austenitic Stainless Steel. Oxidation of Metals, 2011. 76(1): p. 93-109.