CN205388305U - Novel low temperature second grade economizer - Google Patents

Abstract

The utility model relates to a novel low-temperature secondary economizer, comprising an inlet header (1) of the low-temperature secondary economizer, an outlet header (2) of the low-temperature secondary economizer, an upper-level coal-saving unit of the low-temperature secondary economizer economizer (3), low-temperature secondary economizer lower-stage economizer (4), serpentine pipe (5) and hanger (6), outlet header (2) of the low-temperature secondary economizer is set in the low-temperature secondary economizer Above the inlet header (1) of the coal appliance, the inlet header (1) of the low-temperature secondary economizer is connected to the lower economizer (4) of the low-temperature secondary economizer, and the outlet header (2) of the low-temperature secondary economizer It is connected with the upper economizer (3) of the low-temperature secondary economizer, the upper economizer (3) of the low-temperature secondary economizer, and the lower economizer (4) of the low-temperature secondary economizer are connected with serpentine pipes ( 5), the serpentine pipe (5) is suspended on the hanger (6); the utility model realizes the purposes of reducing the exhaust gas temperature of the boiler, increasing power generation, reducing coal consumption, saving desulfurization water consumption, and protecting the chimney.

Description

A new low temperature secondary economizer

[technical field]

The utility model relates to the technical field of boiler preheating recovery, in particular to a novel low-temperature secondary economizer.

[Background technique]

The exhaust gas temperature of many power plant boilers in my country is higher than the design value, which is about 20-30 ℃ higher than the design value. Therefore, reducing the exhaust gas temperature has very important practical significance for saving fuel and reducing pollution. At present, the exhaust gas temperature of domestic power plant boilers is mostly between 120°C and 140°C, and some even reach above 160°C. Therefore, my country's boiler exhaust gas temperature can be greatly reduced, and the corresponding amount of standard coal consumption that can be reduced is also very considerable.

[utility model content]

The purpose of this utility model is to solve the above-mentioned shortcomings and provide a new low-temperature two-stage economizer, which realizes the purpose of reducing the exhaust gas temperature of the boiler, increasing power generation, reducing coal consumption, saving desulfurization water consumption, and protecting the chimney.

In order to achieve the above purpose, a new low-temperature secondary economizer is designed, including low-temperature secondary economizer inlet header 1, low-temperature secondary economizer outlet header 2, low-temperature secondary economizer upper-level economizer 3, The lower-level economizer 4 of the low-temperature secondary economizer, the serpentine pipe 5 and the hanger 6, the outlet header 2 of the low-temperature secondary economizer is arranged above the inlet header 1 of the low-temperature secondary economizer, and the low-temperature secondary economizer The inlet header 1 of the secondary economizer is connected to the lower economizer 4 of the low temperature secondary economizer, and the outlet header 2 of the low temperature secondary economizer is connected to the upper economizer 3 of the low temperature secondary economizer. The upper economizer 3 of the low-temperature secondary economizer and the lower economizer 4 of the low-temperature secondary economizer are connected with serpentine pipes 5 , and the serpentine pipes 5 are suspended on hangers 6 .

The water in the serpentine pipe 5 flows from bottom to top, and the smoke outside the serpentine pipe 5 scours the pipe wall of the serpentine pipe 5 from top to bottom.

The size of the serpentine tube 5 is ф25mm.

The hanger 6 is made of 304 stainless steel.

The serpentine tube 5 uses H-shaped finned tubes as heat exchange elements.

Compared with the prior art, the utility model has the following advantages:

(1) Reliability. The selection of all design parameters first considers the reliable operation of the unit;

(2) Economy. On the premise of reliable operation, the temperature difference of heat exchange is increased as much as possible, the volume and weight of heat exchange surface are reduced, and equipment investment is reduced. On the basis of technical and economical comparison, the lower value of flue gas temperature is reasonably designed to be no less than 20°C. If the flue gas temperature is excessively reduced, in addition to the limitation of the head margin of the fan, the energy saving per unit of flue gas temperature drop will drop rapidly, and the investment recovery period will also be greatly extended;

(3) Reasonable optimization. Strive for the highest energy level of heat recovery. Through the reasonable coupling of the boiler system and the steam turbine system, rationally optimize the location of the water intake and return points of the low-temperature economizer;

(4) safety. Reasonably control the temperature of the metal wall on the heating surface to avoid the dew point of the flue gas. This is a prerequisite for ensuring that the heating surface does not leak, and all schemes must first meet this condition. H-type is used as the heat exchange element, which has the characteristics of high heat transfer efficiency, compact structure, less dust accumulation, good anti-wear performance, strong overall rigidity, etc., and the recovery effect of exhaust heat is good. There is an inspection and maintenance gap (generally 500-600mm) between the high-temperature section and the low-temperature section to facilitate inspection and maintenance. The low-temperature section of the parts in contact with the flue gas is made of sulfuric acid corrosion-resistant steel to ensure that the operating life of the whole machine is ≥ 10 years. The flue gas inlet adopts the structure of deflector and anti-wear pipe, which can evenly enter the smoke and effectively reduce wear;

To sum up, the two-stage low-temperature economizer described in the utility model realizes the purpose of reducing the exhaust gas temperature of the boiler, increasing power generation, reducing coal consumption, saving desulfurization water consumption, and protecting the chimney.

[Description of drawings]

Fig. 1 is a structural representation of the utility model;

In the figure: 1. The inlet header of the low temperature secondary economizer 2. The outlet header of the low temperature secondary economizer 3. The upper economizer of the low temperature secondary economizer 4. The lower economizer of the low temperature secondary economizer 5 , serpentine tube 6, hanger.

[detailed description]

Below in conjunction with accompanying drawing, the utility model is further described as follows:

As shown in the accompanying drawing 1, the utility model includes: the inlet header 1 of the low temperature secondary economizer, the outlet header 2 of the low temperature secondary economizer, the upper economizer 3 of the low temperature secondary economizer, the low temperature secondary economizer Lower-level economizer 4, serpentine pipe 5 and hanger 6 of the coal appliance, the outlet header 2 of the low-temperature secondary economizer is set above the inlet header 1 of the low-temperature secondary economizer, and the inlet header of the low-temperature secondary economizer 1 is connected with the low-level economizer 4 of the low-temperature secondary economizer, the outlet header 2 of the low-temperature secondary economizer is connected with the upper-level economizer 3 of the low-temperature secondary economizer, and the upper-level economizer 3 of the low-temperature secondary economizer 1. The lower economizer 4 of the low-temperature secondary economizer is connected with a serpentine tube 5, which is suspended on the hanger 6, and the hanger 6 is made of 304 stainless steel; the water in the serpentine tube 5 reaches Flowing from bottom to top, the flue gas outside the serpentine tube 5 scours the wall of the serpentine tube 5 horizontally from top to bottom. The size of the serpentine tube 5 is ф25mm. .

The low-temperature two-stage economizer described in the utility model mainly includes: the inlet header of the low-temperature two-stage economizer is arranged below the low-temperature economizer, and is connected with the lower-stage economizer of the low-temperature two-stage economizer; the low-temperature two-stage economizer The outlet header of the economizer is set above the low-temperature economizer and connected to the upper economizer of the low-temperature secondary economizer; the upper economizer of the low-temperature secondary economizer is set to connect to the outlet header; the low-temperature secondary The lower economizer of the economizer is set to connect with the inlet header; the serpentine pipe is set as a component of the upper and lower economizers; the hanger is set as the suspension rod of the upper and lower economizers for suspending the upper and lower Economizer, the material is 304 stainless steel. The upper and lower economizers of the low-temperature secondary economizer have more serpentine tubes than the primary economizer, and the heat exchange surface increases. The serpentine tubes flow from bottom to top, and the flue gas is flushed from the outside to the top and down. The contact area between the flue gas and the heat exchange tube on the tube wall is enlarged to realize a large-area heat exchange between the flue gas and the feed water.

The purpose of this utility model is to provide a boiler exhaust gas is also a waste heat source with great potential at the general boiler exhaust gas temperature, and many new technologies and equipment can be used to reduce the boiler exhaust gas temperature. Smoke exhaust loss is the most important heat loss in boiler operation, generally about 8%, accounting for about 65% of boiler heat loss. The main factor affecting the exhaust heat loss is the exhaust temperature. Generally, for every 10°C increase in the exhaust temperature, the exhaust heat loss will increase by 0.6%-1.0%, and the corresponding additional coal consumption will be 1.2-2.4g/kwh. Reducing the exhaust gas temperature has important practical significance for energy saving and emission reduction. Installing a low-temperature economizer in the tail flue of the boiler can achieve the purpose of deeply recovering the waste heat of the flue gas, increasing power generation, reducing coal consumption, saving desulfurization water consumption, and protecting the chimney.

The utility model is not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principle of the utility model should be equivalent replacement methods, and are all included in Within the protection scope of the present utility model.

Claims (5)

1. A new low-temperature secondary economizer, characterized in that it includes the inlet header (1) of the low-temperature secondary economizer, the outlet header (2) of the low-temperature secondary economizer, and the upper level of the low-temperature secondary economizer Economizer (3), low-temperature secondary economizer lower-stage economizer (4), serpentine pipe (5) and hanger (6), the outlet header (2) of the low-temperature secondary economizer is set at Above the inlet header (1) of the low-temperature secondary economizer, the inlet header (1) of the low-temperature secondary economizer is connected to the lower-stage economizer (4) of the low-temperature secondary economizer, and the low-temperature secondary economizer The outlet header (2) of the coal appliance is connected with the upper economizer (3) of the low temperature secondary economizer, the upper economizer (3) of the low temperature secondary economizer, the lower economizer of the low temperature secondary economizer (4) is connected with a serpentine pipe (5), and the serpentine pipe (5) is suspended on the hanger (6). 2. The new low-temperature secondary economizer according to claim 1, characterized in that: the water in the serpentine pipe (5) flows from bottom to top, and the flue gas outside the serpentine pipe (5) Scour the wall of the serpentine pipe (5) horizontally from top to bottom. 3. The novel low-temperature secondary economizer according to claim 1 or 2, characterized in that: the size of the serpentine tube (5) is ф25mm. 4. The novel low-temperature secondary economizer according to claim 3, characterized in that: the hanger (6) is made of 304 stainless steel. 5. The novel low-temperature secondary economizer according to claim 4, characterized in that: said serpentine tube (5) adopts H-shaped finned tube as a heat exchange element.