A Natural Circulation Split Tube Shell Waste Heat Boiler with Optimized Flow Field Arrangement

Abstract

The invention relates to a natural circulation split shell-and-tube waste heat boiler with optimized flow field layout, which includes a drum and a steam drum. The drum is divided into a flue gas inlet, a heat exchange chamber and a flue gas outlet; The water pipe is connected to the water collection pipe; the heat exchange chamber is arranged with a heat exchange tube bundle; the heat exchange chamber is divided into several heat exchange units by arranging vertical support baffles, and each heat exchange unit is connected to the steam drum through a riser pipe. The upper ends of the ascending tubes extend into the steam drum and are always above the liquid level in the steam drum; there are tube holes on the support baffle for the passage of the heat exchange tube bundle, and there are holes between the tube holes on the lower part of the support baffle. The baffle hole; the steam drum is provided with a steam drum water supply port and several steam outlets; the steam drum is connected with the water collection pipe through the downpipe. The invention can solve the problem that the vapor-liquid two-phase flow in the middle and lower drum of the split-tube shell type waste heat boiler is disordered and the vapor-liquid two-phase flow in the rising pipe is stagnant or even reversed.

Description

【Technical field】 [0001] The invention relates to the field of waste heat recovery, in particular to a natural circulation split shell-and-tube waste heat boiler with optimized flow field arrangement. 【Background technique】 [0002] Waste heat resources, also known as waste heat resources, refer to energy such as heat energy discharged from energy utilization equipment or systems that may be recycled and utilized under current conditions. The waste heat boiler is an important equipment for recovering high-temperature flue gas waste heat. Its essence is a heat exchanger that uses high-temperature flue gas as a heat source to generate steam. The steam generated can be used for power generation, heating, and chemical raw materials. The traditional shell-and-tube waste heat boiler adopts a single-tube shell structure, and the steam generated by the phase change of the working fluid when heated is separated in the same space. In the petrochemical industry, when the flue gas volu...

AI Technical Summary

Problems solved by technology

Between the drum heat exchange tube bundles, flow is closely related to heat exchange, and the turbulent flow of vapor-liquid two-phase fluid will inevitably cause heat transfer deterioration in local areas, greatly shortening the service life of heat exchange tubes

[0004] In addition, the welding between the front and rear tube sheets and the shell and between the tube sheets and the heat exchange tubes of the drum are all welded with dissimilar steels, especially at the front tube sheet where the flue gas temperature is high and the heat flux density is high, which is very easy to Safety accidents such as tube sheet cracking and leakage occur, increasing unplanned maintenance of boilers during operation

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