SaskPower’s Boundary Dam Unit 3 Carbon Capture Facility - The Journey to Achieving Reliability

Abstract

SaskPower’s Integrated Carbon Capture and Storage Project on Boundary Dam’s Unit 3 (BD3 ICCS) began operations in October of 2014. By early October 2020, the facility had captured its 3.5 millionth metric tonne of carbon dioxide (CO2). The road to 3.5 million tonnes of CO2 abated was not without difficulties. As a “first of kind” project, the capture facility at BD3 has been a platform for in-depth learning and optimization. The capture facility experienced unforeseen operational challenges and design oversights which hindered overall performance and significantly reduced its reliability and availability in the early days of operation. Availability of the capture facility did not exceed 70% during the first year and a half of operations while the average daily capture rate in the first 12 months of operation was merely 1240 tonnes/day. Based on experience, reduced capture performance can be attributed to difficulties in three broad categories of process flows: limitations in flue gas flow, limitations in amine flow, and limitations in heat transfer. Equipment responsible for facilitating these flows was identified. Major issues included fly ash accumulation, fouling of key heat exchangers and amine foaming. Corrections and additions to the capture facility were made to increase the facility’s reliability and availability. Corrections and additions to the capture facility including the installation of redundancy and isolations to key pieces of equipment was instrumental in correcting the performance of the facility, increasing its reliability and availability. By the summer of 2019 (May to July) the daily average capture rate was 2580 tonnes/day while availability in the 2018 to 2019 period had improved to over 90%. This paper documents the challenges and measures taken over the first five years of operations to improve the performance of the BD3 ICCS facility.