Search

Corrosion damage and in-service inspection of retractable sootblower lances in recovery boilers, TAPPI Journal October 2021

ABSTRACT: Several reports of accidents involving serious mechanical failures of sootblower lances in chemical recovery boilers are known in the pulp and paper industry. These accidents mainly consisted of detachment and ejection of the lance tip, or even of the entire lance, to the inside of the furnace, towards the opposite wall. At least one of these cases known to the author resulted in a smelt-water explosion in the boiler.In other events, appreciable damage or near-miss conditions have already been experienced. The risk of catastrophic consequences of the eventual detachment of the lance tip or the complete lance of a recovery boiler soot-blower has caught the attention of manufacturers, who have adjusted their quality procedures, but this risk also needs to be carefully considered by the technical staff at pulp mills and in industry committees.This paper briefly describes the failure mechanisms that prevailed in past accidents, while recommending inspection and quality control policies to be applied in order to prevent further occurrences of these dangerous and costly component failures. Digital radiography, in conjunction with other well known inspection techniques, appears to be an effective means to ensure the integrity of sootblower lances in chemical recovery boilers used in the pulp and paper industry.

Corrosion Monitoring and Root Cause Identification in High Solids Concentrators

Black liquor high solids (about 80%) concentrators have often been found to suffer from aggressive corrosion. In particular, the first and second effect bodies are susceptible to corrosion attacks resulting in tube leaks and wall thinning, which limit the availability and lifetime of evaporator lines. Corrosion dynamics and construction materials have been studied extensively within the pulp and paper industry to understand the corrosion process. However, it has been challenging to identify root causes for corrosion, which has limited proactive measures to minimize corrosion damage. Corrosion of the first phase concentrator was studied by defining the potential regions for passive area, stress corrosion cracking, pitting corrosion, and general corrosion. This was achieved by using a technique called polarization scan that reveals ranges for the passive area in which the equipment is naturally protected against corrosion. The open circuit potential, also known as corrosion potential, and linear polarization resistance of the metal were monitored online, which allowed for definition of corrosion risks for stainless steel 304L and duplex stainless steels 2205 and SAF 2906. An online temperature measurement added insight to the analysis. A process diagnostics tool was used to identify root causes of the corrosion attacks. Many of the root causes were related to process conditions triggering corrosion. Once the metal surface was activated, it was difficult to repassivate the metal naturally unless a sufficient potential range was reached.

PIMA/APPTI Decarbonization Investigations Webinar Series - AI

Discover how automation and AI can drive significant CO2 reduction in pulp and paper operations without massive capital investments. Industry expert Pat Dixon reveals four key automation opportunities, including freeness control, basis weight optimization, causticizing efficiency improvements, and kappa number management, that could potentially save 11 million tons of CO2 annually across North America's paper industry. This webinar demonstrates practical applications of predictive analytics, online instrumentation, and process optimization techniques that mid-career professionals can leverage to achieve measurable environmental impact while proving ROI to leadership.

Ahlstrom’s Climate Targets Validated by the Science Based Targets Initiative

Discover Your Company’s Next Generation of Leaders

Have you Forgotten to Submit Your Abstract?

Change in the Management Board of the CHT Group

CPI and Members Showcase UK Paper Industry’s Innovation, Investment, and Impact in Parliament

TAPPI Announces Lawton C. Roberts as its next President and Chief Executive Officer

TAPPI announces Lawton C. Roberts as President and CEO effective November 2025, succeeding retiring industry veteran Larry N. Montague after 19 years of distinguished leadership. Roberts, currently Chief Operating Officer since 2017, brings extensive institutional knowledge and operational expertise to guide the 110-year-old association. His unanimous selection by the Board reflects confidence in continuing TAPPI's member-first approach, global expansion initiatives, and commitment to advancing safety and education standards across pulp, paper, tissue, packaging, and converting industries. This leadership transition ensures seamless continuity for member engagement and industry innovation support.

Södra Tests Carbon Capture Technology at its Värö Mill in Sweden

Södra launches a pioneering carbon capture pilot project at Värö in early 2026, utilizing biogenic CO2 from pulp production to create new revenue streams and strengthen competitiveness. This strategic initiative, supported by Canadian technology partner Svante Technologies and research institute RISE, explores converting captured carbon dioxide into valuable applications including food production, construction materials, and e-fuels. The project exemplifies circular bioeconomy principles by maximizing forest resource value without increasing harvesting, while building industrial expertise for future large-scale implementation. Funded through EU's Industriklivet programme, this innovation positions Södra to meet growing demand for low-carbon products and develop sustainable business models that benefit forest estate profitability.