Natural circulation safety index of water-cooled wall tube

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Natural circulation safety index of water-cooled wall tube The natural circulation safety performance refers to the fact that during the operation of the boiler, all the rising pipes in the circulation loop can have a continuous water film to cool it. The specific indicators are: spraying on the heating surface of the boiler (1) The most heated The weak tube does not have stagnant nuclear backflow; (2) The most heated tube does not suffer from heat transfer deterioration; (3) The loop circulation rate is greater than the limit circulation rate, so that the circulation has compensation characteristics; (4) The entrance of the descending pipe does not form a vortex funnel ; (5) The flow rate and circulation rate of each circulation loop are within the recommended range. In order to improve the circulation safety, the following measures can be taken: (1) Reduce the uneven heating surface of the boiler water wall tubes; (2) Determine the appropriate heat absorption of the riser; (3) Determine the appropriate height and diameter of the riser; ( 4) Determine the appropriate height and cross-sectional area of the steam-water duct; (5) Reduce the resistance of the cyclone separator; (6) Reduce the resistance of the descending pipe. To reduce uneven heating, the operational requirements are: (1) Limit the minimum load, because the load is small, the uneven heating increases; (2) Do not deflect the flame; (3) Prevent slagging, and promptly after slagging Clear.