CN206583315U - A kind of sintering flue gas desulfurization denitration and residual neat recovering system - Google Patents

Abstract

The utility model discloses a sintering flue gas desulfurization and denitrification and waste heat recovery system, comprising a sintering machine, a ring cooler, a ring cooling blower, a high-temperature dust removal unit, a selective catalytic reduction denitrification unit, a waste heat boiler, a desulfurization unit, a main exhaust fan, Chimney, large sintering flue, blower, low-temperature dust removal unit; the sintering machine is connected with the large sintering flue; the gas outlet of the large sintering flue is connected to the air inlet of the low-temperature dust removal unit and the ring The air inlet of the cold blower is connected; the ring cooling blower, the ring cooler, the high temperature dedusting unit, the selective catalytic reduction denitrification unit, the waste heat boiler, the desulfurization unit, the main exhaust fan and the chimney are connected in sequence; The air port is connected with the air inlet of the desulfurization unit. The utility model can not only reduce the investment and operation cost of sintering flue gas desulfurization and denitrification, but also can recover waste heat in the sintering production process, and has good economic benefits.

Description

A sintering flue gas desulfurization and denitration and waste heat recovery system

technical field

The utility model relates to the field of metallurgical industry, in particular to a sintering flue gas desulfurization and denitrification and waste heat recovery system.

Background technique

A large amount of air pollutants will be produced in the process of iron and steel production. Sintering production is one of the most important process units in modern iron and steel production. The NO _X emissions generated during the sintering process account for about 10% of the total NO _X emissions of iron and steel plants. 48%, so sintering flue gas denitrification and desulfurization has become the top priority of environmental governance in iron and steel enterprises. At present, foreign sintering flue gas denitrification technologies mainly include activated carbon (coke) adsorption method, circulating fluidized bed method, high energy radiation-chemical method, semi-dry spray method and MWROS flue gas purification technology. The investment and operation costs of the above methods are very high. Now coal-fired power plants generally adopt a very mature selective catalytic reduction denitrification technology, that is, SCR denitrification technology. Low (<200°C), it is difficult to apply this mature Selective Catalytic Reduction (SCR) denitrification technology.

At the same time, China's iron and steel industry is the second largest energy-intensive and highly polluting industry next to the power industry. The energy consumption of the sintering process accounts for 10% to 20% of the total energy consumption of the iron and steel industry. According to statistics, the production of 1 ton of sintered ore produces The amount of waste heat resources is 1000-1300MJ/t, which mainly comes from cooling sinter and sinter flue gas. The waste heat resources are abundant. However, only a small amount of waste heat resources are recycled in the traditional sintering machine waste heat recovery system, and waste heat resources are seriously wasted.

In view of the above situation, a sintering flue gas desulfurization and denitrification and waste heat recovery system for sintering machines is needed.

Utility model content

The technical problem to be solved by the utility model is to provide a sintering flue gas desulfurization and denitrification and waste heat recovery system. The utility model can use the sensible heat of cooling sinter to heat the sintering flue gas containing nitrogen oxides to meet the requirements of selective catalytic Reduction (SCR) denitrification technology flue gas reaction temperature requirements, but also recovery of cooling sinter sensible heat in the ring cooler and sintering flue gas waste heat generated during the sintering process in the sintering machine, while reducing the investment in sintering flue gas desulfurization and denitrification It has good economic and social benefits.

The technical scheme that the utility model solves technical problem is as follows:

The utility model discloses a sintering flue gas desulfurization and denitrification and waste heat recovery system. The system includes a sintering machine, a ring cooler, a ring cooling blower, a high-temperature dust removal unit, a selective catalytic reduction denitrification unit, a waste heat boiler, a desulfurization unit, a main exhaust fan, Chimney, large sintering flue, and low-temperature dust removal unit; the sintering machine communicates with the large sintering flue; the gas outlet of the large sintering flue is connected to the air inlet of the low-temperature dust removal unit and the ring cooling blower respectively The air inlet is connected; the annular cooling blower, annular cooler, high-temperature dedusting unit, selective catalytic reduction denitrification unit, waste heat boiler, desulfurization unit, main exhaust fan, and chimney are connected in sequence through pipelines; the gas outlet of the low-temperature dedusting unit Connect with the air inlet of the desulfurization unit.

Further, the air outlet of the low-temperature dedusting unit is also connected to the air inlet of the selective catalytic reduction denitrification unit.

Further, a blower is provided between the air outlet of the low-temperature dedusting unit and the air inlet of the selective catalytic reduction denitrification unit.

Further, the high temperature dust removal unit is an electric dust collector.

Further, the low-temperature dust removal unit is a bag filter.

Compared with the prior art, the utility model has the following advantages: (1) Utilize the sensible heat of cooling sinter to increase the temperature of sinter flue gas to make it reach the reaction temperature of selective catalytic reduction denitrification unit (SCR); (2) Exchange heat between the denitrated high-temperature flue gas and the waste heat boiler, and the steam generated by the waste heat boiler absorbing the heat in the flue gas can be used by steam users, such as power generation; (3) denitration and desulfurization of sintering flue gas can be completed without additional resource consumption, At the same time, the recovery and reuse of waste heat resources are also completed; (4) The investment and operation costs of the selective catalytic reduction denitrification unit (SCR) are very low, and it has high economic and social benefits.

Description of drawings

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

In the figure: 1. Sintering machine, 2. Ring cooler, 3. Ring cooling blower, 4. High temperature dust removal unit, 5. Selective catalytic reduction denitrification unit, 6. Waste heat boiler, 7. Desulfurization unit, 8. Main exhaust fan , 9. Chimney, 10. Large sintering flue, 11. Blower, 12. Low temperature dust removal unit.

detailed description

In order to better explain the utility model, the content of the utility model is further clarified below in conjunction with the accompanying drawings and specific embodiments, but the content of the utility model is not limited to the following examples.

As shown in Figure 1, the utility model is a sintering flue gas desulfurization and denitration and waste heat recovery system, the system includes a sintering machine 1, an annular cooler 2, an annular cooling blower 3, a high-temperature dust removal unit 4, and a selective catalytic reduction denitrification unit 5 , waste heat boiler 6, desulfurization unit 7, main exhaust fan 8, chimney 9, large sintering flue 10, low-temperature dust removal unit 12; the sintering machine 1 communicates with the large sintering flue 10; the large sintering flue The air outlet of 10 is respectively connected with the air inlet of the low-temperature dedusting unit 12 and the air inlet of the ring cooling blower 3; the air outlet of the ring cooling blower 3 is connected with the air inlet of the ring cooler 2, and the ring The air outlet of the refrigerator 2 is connected to the air inlet of the high-temperature dedusting unit 4, the air outlet of the high-temperature dedusting unit 4 is connected to the air inlet of the selective catalytic reduction denitrification unit 5, and the selective catalytic reduction denitrification unit 5 The air outlet is connected to the air inlet of the waste heat boiler 6, the air outlet of the waste heat boiler 6 is connected to the air inlet of the desulfurization unit 7, and the air outlet of the desulfurization unit 7 is connected to the air inlet of the main exhaust fan 8 The air outlet of the main exhaust fan 8 is connected to the air inlet of the chimney 9; the air outlet of the low-temperature dust removal unit 12 is connected to the air inlet of the desulfurization unit 7.

In this embodiment, the gas outlet of the low-temperature dedusting unit 12 can also be connected to the gas inlet of the selective catalytic reduction denitrification unit 5 .

In this embodiment, a blower 11 may further be provided between the air outlet of the low-temperature dedusting unit 12 and the air inlet of the selective catalytic reduction denitrification unit 5 .

The high temperature dust removal unit 4 in this embodiment may be an electric dust collector.

The low-temperature dust removal unit 12 in this embodiment may be a bag filter.

In this embodiment, the sintering machine 1 is communicated with the large sintering flue 10 arranged at its lower part. During the normal sintering process, the flue gas temperature in the sintering flue is 50°C to 150°C, and the content of nitrogen oxides, sulfur dioxide and dust is very high. In this embodiment, the flue gas in the sintering flue 10 is divided into It is divided into two parts, a part of the sintering flue gas is sent to the ring cooler 2 through the ring cooling blower 3, and the cooling sinter is placed in the ring cooler 2, and the cooling sinter can use the cooling sinter and sinter smoke from the sintering machine 1 After the gas absorbs and cools the sensible heat of the sinter, the temperature rises to 300°C to 450°C, and then enters the high-temperature dust removal unit 4. The high-temperature dust removal unit 4 can use an electric dust collector, etc. The temperature of the sintering flue gas after the high-temperature dust removal unit 4 is dedusted is 300 ℃～450℃; another part of the flue gas in the large sintering flue 10 enters the low-temperature dust removal unit 12, and the low-temperature dust removal unit 12 can use a bag filter or the like. ℃, this part of the low-temperature sintering flue gas is further divided into two parts, a part of the low-temperature sintering flue gas is mixed with the above-mentioned 300-450 °C sintering flue gas after passing through the high-temperature dust removal unit 4 through the blower 11, and the mixing is achieved by controlling the air volume of the blower 11 Afterwards, the temperature of the flue gas is between 260°C and 350°C, ensuring the requirement of the flue gas temperature at the entrance of the Selective Catalytic Reduction Denitration Unit (SCR) 5 for denitrification. After denitrification, it enters the waste heat boiler 6, which absorbs the sintering flue gas The heat generated in the steam can be used for steam users, which can be used for power generation, etc.; another part of the low-temperature sintering flue gas is mixed with the flue gas after passing through the waste heat boiler 6, and the temperature after mixing is 50 ° C ~ 150 ° C, and then enters the desulfurization unit 7 for Desulfurization, and then pumped into the chimney 9 through the main exhaust fan 8 to release flue gas that meets environmental protection requirements.

The utility model utilizes the sensible heat of cooling sintered ore to heat the sintering flue gas containing nitrogen oxides, by means of mixing part of the low-temperature sintering flue gas to meet the requirements of the inlet temperature of the flue gas in the Selective Catalytic Reduction (SCR) technology; and also The sensible heat of sintering in the ring cooler and the waste heat of sintering flue gas produced during the sintering process in the sintering machine are recovered. Therefore, the utility model can not only reduce the investment cost of sintering flue gas desulfurization and denitrification, but also can recover waste heat in the production process of sintering process. It is a very innovative sintering flue gas desulfurization and denitrification and waste heat recovery process.

Claims (5)

1. A sintering flue gas desulfurization and denitrification and waste heat recovery system, characterized in that: the system includes a sintering machine (1), a ring cooler (2), a ring cooling blower (3), a high temperature dust removal unit (4), a selective Catalytic reduction denitrification unit (5), waste heat boiler (6), desulfurization unit (7), main exhaust fan (8), chimney (9), sintering large flue (10), low-temperature dust removal unit (12); the sintering The machine (1) is connected with the large sintering flue (10); the gas outlet of the large sintering flue (10) is connected with the air inlet of the low-temperature dedusting unit (12) and the annular cooling blower (3) respectively. ) air inlet connection; the annular cooling blower (3), annular cooler (2), high temperature dust removal unit (4), selective catalytic reduction denitrification unit (5), waste heat boiler (6), desulfurization unit (7) , the main exhaust fan (8), and the chimney (9) are sequentially connected through pipelines; the air outlet of the low-temperature dust removal unit (12) is connected with the air inlet of the desulfurization unit (7). 2. A sintering flue gas desulfurization and denitrification and waste heat recovery system according to claim 1, characterized in that: the gas outlet of the low-temperature dust removal unit (12) is also connected to the air inlet of the selective catalytic reduction denitrification unit (5) connect. 3. A sintering flue gas desulfurization and denitrification and waste heat recovery system according to claim 2, characterized in that: the air outlet of the low-temperature dust removal unit (12) and the air inlet of the selective catalytic reduction denitrification unit (5) A blower (11) is arranged between them. 4. A sintering flue gas desulfurization, denitrification and waste heat recovery system according to claim 1, characterized in that: the high temperature dust removal unit (4) is an electric precipitator. 5. A sintering flue gas desulfurization, denitrification and waste heat recovery system according to claim 1, characterized in that: the low-temperature dust removal unit (12) is a bag filter.