SU870849A1 - Soda regeneration boiler - Google Patents

Description

(54) CODARING BOILER

I

The invention relates to the field of energy and can be used for burning black liquor sulphate pulping in the pulp and paper industry.

Closest to the invention is a recovery boiler containing a vertical furnace formed by pipes of the lower and upper screens connected to the inlet and outlet headers 1.

The disadvantage of this recovery boiler is the increased explosive hazard, since when the screen tube is broken, a large amount of water enters the melt located on the bottom of the furnace, which leads to an explosion.

The aim of the invention is to increase the safety of the recovery boiler.

This goal is achieved by the fact that the pipes of the lower screen are made in the form of heat pipes, the upper ends of which are installed in the collectors of the lower screen.

FIG. L depicts a soda recovery boiler, the option of including the heat pipe condensation zone in the feedwater preheating circuit before the second stage

economizer; in fig. 2 - the same, the option of including the heat pipe condensation zone in the low pressure circuit.

The recovery boiler contains a vertical firebox 1, formed by pipes 2 and 3, respectively, of the lower and upper screens. Pipes 2 are connected to inlet 4 and outlet 5 collectors, and pipes 3 are connected to inlet 6 and outlet 7 collectors. The pipes 2 of the lower screen are made in the form of heat pipes, the upper ends of which are installed in the collectors 4 and 5 of the lower screen, interconnected by pipes 8 and supplied respectively with feed 9 and discharge 10 pipes. The pipes 3 of the upper screen form an evaporative heating surface. The collectors 4 and 5, connected by nozzles 8, form a zone of condensation of heat pipes. In this case, the condensation zone of heat pipes can be included (see Fig. 1) in the feedwater heating circuit before the second stage of economizer 11 or in the low pressure circuit of the boiler (see Fig. 2) formed by a drum separator 12 and pipes 9 and ten.

Black liquor is injected into the furnace 1 of the boiler, which is sprayed, dried and burned to form flue gases and a layer of melting candle on the hearth of the furnace 1. The heat released during this process heats the heat transfer fluid. Part of the heat carrier coolant evaporates in the furnace and enters the condensation tank, where it gives off heat to feed water before the economizer (see Fig. I) or boiler water in the low pressure circuit (see Fig. 2).

In the event of a rupture of the pipe 3 of the upper screen of the furnace 1, the water that flows out of the broken pipe 3 manages to evaporate before it reaches the level of the melt. In this case, the probability of an explosion is negligible. In case of rupture of the pipe 2 of the lower screen, the heat carrier coolant enters the melt, which, when interacting with the melt, does not produce an explosion. Moreover, the rupture of the pipe 2 of the lower screen does not cause an emergency and does not require the immediate shutdown of the boiler. Repair defective heat pipe. May be timed

repair of the remaining equipment of the pulp production process flow.

Thus, the construction of pipes 2 of the lower screen in the form of heat pipes, the upper ends of which are installed in the collectors of the lower screen, makes it possible to increase the safety of the recovery boiler.

Claims (1)

Invention Formula A recovery boiler comprising a vertical furnace formed by pipes of the lower and upper screens connected to the inlet and outlet manifolds, characterized in that, in order to increase safety, the pipes of the lower screen are made in the form of heat pipes whose upper ends are installed in the collectors of the lower screen. Information sources, taken into account during the examination 1. USSR Copyright Certificate No. 383958, cl. F 22 V 1/20, 1970. X