Application device for recycling and improving heat energy of HRS under acid mixing

Abstract

The utility model relates to the technical field of acid-making heat energy recovery, in particular to an application device for recovering and improving heat energy of an HRS under acid mixing. The HRS tower is connected with the HRS steam generator through the HRS acid circulating pump, one outlet of the HRS steam generator is connected with an inlet of the HRS diluter, an outlet of the HRS diluter is connected with the HRS tower, the other outlet of the HRS steam generator is sequentially connected with the HRS heater, the jet steam generator, the serial acid preheater and the HRS preheater, external deoxygenated water is connected with the jet steam generator through a pipeline, and the jet steam generator is connected with the HRS heater through a pipeline. And one outlet of the jet steam generator is communicated with a steam outlet of the HRS steam generator and then is communicated with the HRS tower through a steam jet. Compared with the prior art, an existing acid making heat energy recovery system is improved, the jet steam generator and the serial acid preheater are additionally arranged, serial acid and steam jet restrictions can be unlocked, high-temperature sulfuric acid in an HRS system production process is used as a heat source as much as possible, the yield of 0.6-1.0 MPaG low-pressure steam is remarkably increased, and the heat energy recovery utilization rate is increased.

Description

Technical Field

[0001] This utility model relates to the field of acid production heat energy recovery technology, specifically an application device for improving heat energy recovery in an HRS system under acid production. Background Technology

[0002] Currently, heat recovery efficiency is highly valued in sulfuric acid production from smelting flue gas, pyrite, and sulfur. The heat energy sources for steam generation in these sulfuric acid production units mainly fall into three categories: 1. Heat energy from sulfur combustion; 2. Heat of conversion during the SO2 to SO3 conversion process; 3. The establishment of a low-temperature heat recovery system (HRS) for saturated steam to recover heat generated during sulfuric acid production. However, the following problems exist in sulfuric acid production units from smelting flue gas and sulfuric acid production units in high-humidity areas: 1. The flue gas at the outlet after purification contains a large amount of water vapor; 2. A large amount of water vapor is introduced from the air, exceeding the amount needed to maintain the dry absorption system and the product acid. To maintain water balance, the dry absorption system needs to be connected to the HRS. Furthermore, the HRS system has a steam ejector that consumes some of the steam generated by the HRS steam generator. Therefore, the steam output of the HRS is constrained by these two factors. To improve the economic efficiency of the unit, increasing the steam output of the HRS has become an urgent need. Summary of the Invention

[0003] This invention aims to overcome the shortcomings of existing technologies by providing an application device for improving heat recovery in HRS systems under acidic conditions.

[0004] To achieve the above objectives, an application device for heat recovery and enhancement of an HRS system under acid cascading is designed, comprising an HRS tower. The HRS tower is connected to an HRS steam generator via an HRS acid circulation pump. One outlet of the HRS steam generator is connected to the inlet of an HRS diluent, and the outlet of the HRS diluent is connected to the HRS tower. The other outlet of the HRS steam generator is sequentially connected to an HRS heater, a jet steam generator, an acid cascading preheater, and another HRS preheater. External deoxygenated water is connected to the jet steam generator via a pipeline. One outlet of the jet steam generator is connected to the steam outlet of the HRS steam generator and together they are connected to the HRS tower via a steam ejector.

[0005] The HRS steam generator outputs low-pressure steam from its steam outlet.

[0006] External deoxygenated water is connected to one inlet of the HRS heater via a pipeline, and the corresponding outlet of the HRS heater is connected to the HRS steam generator.

[0007] The sulfuric acid pipeline is connected to the acid preheater and then to the HRS diluent. External deoxygenated water is connected to the HRS diluent through a pipeline. The heated sulfuric acid and external deoxygenated water are mixed in the HRS diluent and then enter the HRS tower.

[0008] External demineralized water enters the HRS preheater through the demineralized water inlet pipe and then flows out through the demineralized water outlet pipe.

[0009] Temperature monitoring points and control valves are installed on the pipelines before and after the jet steam generator and acid preheater.

[0010] The materials in the jet steam generator and acid preheater that come into contact with acid are made of acid-resistant stainless steel, while the materials that come into contact with water and steam are made of carbon steel.

[0011] Compared with the prior art, this utility model improves the existing acid production heat energy recovery system by adding a jet steam generator and a series acid preheater, which can unlock the constraints of series acid and steam jet, and make full use of the high-temperature sulfuric acid in the HRS system production process as a heat source, significantly increasing the output of 0.6~1.0MPaG low-pressure steam, improving the heat energy recovery and utilization rate, and generating more economic benefits. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings.

[0014] like Figure 1 As shown, HRS tower 1 is connected to HRS steam generator 3 via HRS acid circulation pump 2. One outlet of HRS steam generator 3 is connected to the inlet of HRS diluter 4. The outlet of HRS diluter 4 is connected to HRS tower 1. The other outlet of HRS steam generator 3 is connected in sequence to HRS heater 5, jet steam generator 6, acid preheater 7, and HRS preheater 8. External deoxygenated water 10 is connected to jet steam generator 6 via a pipeline. One outlet of jet steam generator 6 is connected to the steam outlet of HRS steam generator 3 and then both are connected to HRS tower 1 via steam ejector 9.

[0015] The steam outlet of HRS steam generator 3 outputs low-pressure steam 11.

[0016] External deoxygenated water 10 is connected to one inlet of HRS heater 5 through a pipe. The corresponding outlet of HRS heater 5 is connected to HRS steam generator 3 to heat the deoxygenated water. The water then enters HRS steam generator 3 to generate steam, thus improving thermal energy utilization.

[0017] Sulfuric acid pipeline 12 connects to acid preheater 7 and then to HRS diluter 4. External deoxygenated water 10 is connected to HRS diluter 4 via a pipeline. The heated sulfuric acid and external deoxygenated water 10 are mixed in HRS diluter 4 and then enter HRS tower 1. The dilution water and heated acid are continuously mixed with the acid downstream of HRS steam generator 3 to control the acid concentration above 99.0%. This portion of the acid is then recycled to HRS tower 1. The added dilution water and acid generate heat through SO3 absorption, causing the temperature of the circulating acid to rise.

[0018] External demineralized water enters the HRS preheater 8 through the demineralized water inlet pipe 13 and then flows out through the demineralized water outlet pipe 14 to heat the demineralized water.

[0019] Temperature monitoring points and control valves are installed on the pipelines before and after the jet steam generator 6 and the acid preheater 7. The temperature is controlled by adjusting the amount of material entering the jet steam generator 6 and the acid preheater 7 according to the set temperature parameters.

[0020] The materials in contact with acid in the jet steam generator 6 and the acid preheater 7 are made of acid-resistant stainless steel, while the materials in contact with water and steam are made of carbon steel.

[0021] In use, the acid is pumped from the HRS acid circulation pump 2 on the HRS tower 1 pump tank to the HRS steam generator 3. After leaving the HRS steam generator 3, the acid splits into two streams. Most of the cooled acid flows through the HRS diluter 4 and then returns to the HRS tower 1 for circulation. A small portion, which will be used as product acid, is cooled by passing through the HRS heater 5, jet steam generator 6, acid preheater 7, and HRS preheater 8, transferring heat to the deoxygenated water, acid, and demineralized water. The acid flowing through the HRS heater 5, jet steam generator 6, acid preheater 7, and HRS preheater 8 then flows into the dry acid absorption system.

[0022] The high-temperature sulfuric acid (serial number 8) flowing through the HRS heater 5 has a temperature of 145~200℃, which provides a heating medium for the jet steam generator 6 and the acid preheater 7. It transfers heat to the deoxygenated water (serial number 15) and the acid (serial number 12), and then flows out from the heat source medium outlet of the acid preheater 7 into the HRS preheater 8.

[0023] The deoxygenated water flowing through the jet steam generator 6 exchanges heat with high-temperature sulfuric acid to generate 0.1~0.3MPaG saturated low-pressure steam (serial number 20). This part of the steam is combined with part of the steam (serial number 21) separated from the HRS steam generator 3, and then sent into the flue gas system of HRS tower 1 after pressure reduction to maintain the water volume required for HRS acid concentration, and transfer the heat energy to the high-temperature circulating acid system to generate more 0.6~1.0MPaG saturated low-pressure steam.

[0024] In practical use, process gas from the main acid production unit's conversion system enters steam ejector 9, where it mixes with steam produced by HRS steam generator 3 and jet steam generator 6. HRS tower 1 receives SO3 gas from steam ejector 9. SO3 and H2SO4 vapors come into contact with circulating acid flowing from bottom to top and from top to bottom. SO3 is absorbed by the circulating acid, which accumulates in the pump tank of HRS tower 1 and is circulated by a submerged vertical centrifugal pump installed on the pump tank.

[0025] This invention recovers heat energy during the acid production process and can be applied to acid production from smelting flue gas, acid production from pyrite, and sulfuric acid production in high-humidity areas.

[0026] In this invention, the jet steam generator 6 uses the high-temperature sulfuric acid from the HRS heater 5 to heat the deoxygenated water, transferring the high-temperature heat from the sulfuric acid to the deoxygenated water in the jet steam generator 6 to generate 0.1~0.3 MPaG saturated low-pressure steam. The acid preheater 7 uses the high-temperature sulfuric acid from the jet steam generator 6 to heat the low-temperature acid from the dry absorption system, transferring the heat energy from acid production to the acid preheater, returning it to the high-temperature sulfuric acid system. By utilizing the high-temperature sulfuric acid in the HRS system production process as a heat source as much as possible, the production of 0.6~1.0 MPaG low-pressure steam is significantly increased, improving heat recovery and utilization efficiency, and generating greater economic benefits.

Claims

1. An application device for heat recovery and enhancement of an HRS system under acidic conditions, comprising an HRS tower, characterized in that: The HRS tower (1) is connected to the HRS steam generator (3) via the HRS acid circulation pump (2). One outlet of the HRS steam generator (3) is connected to the inlet of the HRS diluent (4). The outlet of the HRS diluent (4) is connected to the HRS tower (1). The other outlet of the HRS steam generator (3) is connected in sequence to the HRS heater (5), the jet steam generator (6), the acid preheater (7), and the HRS preheater (8). The external deoxygenated water (10) is connected to the jet steam generator (6) via a pipeline. One outlet of the jet steam generator (6) is connected to the steam outlet of the HRS steam generator (3) and then connected to the HRS tower (1) via the steam ejector (9).

2. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1, characterized in that: The HRS steam generator (3) outputs low-pressure steam (11) at its steam outlet.

3. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1, characterized in that: External deoxygenated water (10) is connected to one inlet of HRS heater (5) via a pipe, and the corresponding outlet of HRS heater (5) is connected to HRS steam generator (3).

4. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1, characterized in that: The sulfuric acid pipeline (12) is connected to the acid preheater (7) and then connected to the HRS diluter (4). The external deoxygenated water (10) is connected to the HRS diluter (4) through the pipeline. The heated sulfuric acid and the external deoxygenated water (10) are mixed in the HRS diluter (4) and then enter the HRS tower (1).

5. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1, characterized in that: The external demineralized water enters the HRS preheater (8) through the demineralized water inlet pipe (13) and then flows out through the demineralized water outlet pipe (14).

6. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1, characterized in that: Temperature monitoring points and control valves are installed on the pipelines before and after the jet steam generator (6) and the acid preheater (7).

7. The application device for heat recovery and enhancement of HRS system under acid conditions according to claim 1 or 6, characterized in that: The materials in the jet steam generator (6) and the acid preheater (7) that come into contact with acid are made of acid-resistant stainless steel, while the materials that come into contact with water and steam are made of carbon steel.

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