A Review Of The Conditions In Chemical Recovery Boilers That Result In Poor-Flowing Smelt

摘要

In response to numerous requests from kraft mills experiencing difficulties with the smelt flow from their recovery boilers, we conducted a literature review on the process and operating variables responsible for this problem. Poor-flowing smelt has been noted to lead to dissolving tank explosions, as well as plugged smelt spouts. The review found that the existing information about causes and solutions to smelt flow problems was largely anecdotal, and not always easy to apply. Some useful information was obtained, and the effects of several factors are summarized, including black liquor chemical properties, boiler operating conditions, and smelt composition on smelt melting points and viscosity. Recommendations are given on how to identify the cause of a problem. Once the cause is identified, the actions to solve or lessen its effect on boiler operation are usually evident.