Natural circulating steam injection boiler fed with high salt-containing softened water and water circulating method

Abstract

The invention discloses a natural circulating steam injection boiler fed with high salt-containing softened water and a water circulating method, and belongs to the fields of natural circulating steam pocket water power technology and stage evaporation technology. A steam pocket is divided into a net section and a salt section, boiler feed water is directly introduced into a vertical down pipe of the net section of the steam pocket, and the evaporation heating surface of the net section is arranged on the heating surface of a hearth. The feed water of the salt section of the steam pocket is supplied by the boiler water of the net section, the evaporation heating surface of the salt section is arranged in a flue at the tail of the boiler, and the sewerage is directly led out by a steam-water separation device on the salt section of the boiler. The blow-down rate of the boiler is 5 to 15 percent, and the evaporation capacity of the salt section is 5 to 40 percent of the total evaporation capacity. Under the same blow-down rate, the boiler water of the net section and salt section heating surfaces of the boiler has low salt content; the heating surfaces have good corrosion resistance, hydrodynamic characteristic and safe heat transfer; and the heating surface of the salt section is convenient for overhauling. The fuel of the boiler can be coal, oil, natural gas and other combustible solids, and is suitable for high-capacity thick oil thermal recovery steam injection boilers.

Description

technical field [0001] The invention relates to a natural circulation drum type steam injection boiler, in particular to a natural circulation steam injection boiler using high-salt demineralized water as feed water and a water circulation method, belonging to the technical field of heavy oil steam injection thermal recovery and boiler equipment. Background technique [0002] The oil field steam injection boiler is a special equipment for heavy oil steam injection thermal recovery. The steam generated by the steam injection boiler is injected into the ground to heat the heavy oil, and then it is extracted together with the heavy oil, and then recycled after oil-water separation and sewage treatment. . At present, my country's oilfields mainly use traditional high-pressure / subcritical once-through boilers that burn crude oil and natural gas. Since the once-through boilers cannot discharge the salt, the salt in the water is concentrated as the dryness of the steam increases. ...

AI Technical Summary

Problems solved by technology

These requirements largely limit the scope of application of once-through steam injection boilers

However, due to the economic considerations of oilfield sewage treatment and the actual situation of poor sewage water quality, the water quality of recycled heavy oil demineralized water is difficult to meet the water quality requirements of ordinary boilers

On the other hand, since the steam generated by steam injection boilers is directly used for oil production, the requirements for steam quality are greatly reduced, making the water quality requirements of ordinary boilers too strict for steam injection boilers

Images