Thermal energy utilization device for full production of high-pressure steam in sulfuric acid production

Abstract

The present utility model relates to the technical field of thermal energy utilization, and specifically to a thermal energy utilization device for full production of high-pressure steam in sulfuric acid production. The temperature of high-temperature sulfuric acid of a lower unit of a low-temperature heat recovery absorption tower is 240-280°C; an acid-side outlet of the low-temperature heat recovery absorption tower is divided into several parts, which are respectively connected to acid-side inlets of a high-pressure heater, a flue gas heater and an air heater; acid-side outlets of the high-pressure heater, the flue gas heater and the air heater converge and then connect to an inlet of a low-temperature heat recovery absorption tower diluter; an outlet of the low-temperature heat recovery absorption tower diluter is connected to the low-temperature heat recovery absorption tower; the acid-side outlet of the flue gas heater is further connected to an acid-side inlet of a preheater; an acid-side outlet of the preheater is connected to both a secondary absorption unit and a drying unit. Compared with the prior art, the present utility model increases the acid temperature of low-temperature heat recovery systems in existing sulfuric acid production devices and implements heat transfer so as to fully produce high-pressure steam, and no longer produces low-pressure steam, such that low-pressure steam systems are eliminated, thus simplifying systems.

Description

A kind of heat energy utilization device of high-pressure steam in sulfuric acid production TECHNICAL FIELD

[0001] The utility model relates to heat energy utilization technical field, specifically to a kind of heat energy utilization device of high-pressure steam in sulfuric acid production. BACKGROUND

[0002] At present, whether the heat recovery system of sulfuric acid industry is efficient is the most important of the whole device, the current sulfur-burning sulfuric acid plant ton acid steam production is in: 3.0~9.8MPa, 400~540 ℃ high-pressure steam 1.25~1.32t / t acid, with low-temperature heat recovery system, abbreviated as: HRS (Heat Recovery Systems), can produce 0.6~1.0MPa low-pressure saturated steam ~0.45t / t acid;The price difference of the two kinds of steam is large in the market, so it is urgent to improve the high-pressure steam production to produce more economic benefits for sulfuric acid industry.

[0003] The Chinese patent with application number CN2024105933155 discloses a kind of, by according to the use scene, object flexible configuration three sets of heat exchanger, as far as possible utilize the heat in sulfuric acid production, improve the production of high-pressure steam.But in actual use, it is found that the acid temperature of the lower tower of HRS tower does not exceed 230 DEG C, the acid temperature is not high enough, and the temperature difference is not enough to react SO 3 And water in HRS tower to generate sulfuric acid reaction heat is all transferred to high-pressure steam system, only the output part of low-pressure steam, there is no way to produce high-pressure steam. INVENTION CONTENTS

[0004] The utility model provides a kind of heat energy utilization device of high-pressure steam in sulfuric acid production to overcome the deficiency of prior art, the heat of low-pressure steam produced by existing low-temperature heat recovery system is transferred and all high-pressure steam is produced, without low-pressure steam, reduce low-pressure steam system, produce more economic benefits.

[0005] To achieve the above object, a kind of heat energy utilization device of high-pressure steam in sulfuric acid production is designed, including low-temperature heat recovery absorption tower, the high-temperature sulfuric acid temperature of the lower tower of low-temperature heat recovery absorption tower is 240-280 DEG C, the acid side outlet of the low-temperature heat recovery absorption tower is divided into several roads, respectively connect the acid side inlet of high-pressure heater, flue gas heater, air heater;The acid side outlet of high-pressure heater, flue gas heater, air heater is gathered and then connected with the inlet of low-temperature heat recovery absorption tower diluter, the outlet of low-temperature heat recovery absorption tower diluter is connected with low-temperature heat recovery absorption tower, the acid side outlet of flue gas heater is also connected with the acid side inlet of preheater, the acid side outlet of preheater is connected with secondary absorption unit, drying unit respectively.

[0006] The air temperature at the air heater inlet is 60-130 DEG C, the air temperature at the air heater outlet is 220-260 DEG C; the flue gas temperature at the flue gas heater inlet is 70-90 DEG C, the flue gas temperature at the flue gas heater inlet is 200-250 DEG C; the steam temperature at the high-pressure heater inlet is 104 DEG C-170 DEG C, the steam temperature at the high-pressure heater outlet is 200-260 DEG C.

[0007] The water side inlet of the preheater is connected with the high-pressure steam system, in which the water side inlet of the preheater is connected with a desalted water source, the water side outlet of the preheater is connected with the inlet of a deaerator, the outlet of the deaerator is connected with a boiler water feeding pump, a boiler medicine device, the water side inlet of an economizer 3A, the water side inlet of an economizer 4A, and a diluter dilution water pipeline; the water side outlet of the economizer 3A and the water side outlet of the economizer 4A are merged into one, and are connected with the water side inlet of the high-pressure heater; the water side outlet of the high-pressure heater is divided into two, and is connected with the water side inlet of an economizer 3B and the water side inlet of an economizer 4B; the water side outlet of the economizer 3B and the water side outlet of the economizer 4B are merged into one, and are connected with the water side inlet of a waste heat boiler and the steam side inlet of the waste heat boiler; the steam side outlet of a superheater 4A is connected with the steam side inlet of a superheater 1B, and the steam side outlet of the superheater 1B produces high-pressure steam.

[0008] The drying unit comprises an air filter, a drying tower, the air filter is connected with an air source at one end, the air filter is connected with the drying tower at the other end, the outlet of the drying tower is connected with the inlet of a fan, the outlet of the fan is connected with an air heater, the outlet of the air heater is connected with the incineration unit; the incineration unit comprises a sulfur incinerator and a waste heat boiler, the outlet of the main fan, a liquid sulfur source are connected with the inlet of the sulfur incinerator, the outlet of the sulfur incinerator is connected with the flue gas side inlet of the waste heat boiler, the flue gas side outlet of the waste heat boiler is connected with the conversion unit, the conversion unit comprises a converter, a high-temperature heat exchanger and a low-temperature heat exchanger, the flue gas side outlet of the waste heat boiler is connected with the inlet of the first section of the converter, the outlet of the first section of the converter is connected with the flue gas side inlet of the superheater 1B, the flue gas side outlet of the superheater 1B is connected with the inlet of the second section of the converter, the outlet of the second section of the converter is connected with the first inlet of the high-temperature heat exchanger, the first outlet of the high-temperature heat exchanger is connected with the inlet of the third section of the converter, the third outlet of the converter is connected with the first inlet of the low-temperature heat exchanger, the first outlet of the low-temperature heat exchanger is connected with the flue gas side inlet of the economizer 3B, the flue gas side inlet of the economizer 3B is connected with the flue gas side inlet of the economizer 3A, the flue gas side outlet of the economizer 3A is connected with the primary absorption unit, the primary absorption unit comprises a low-temperature heat recovery absorption tower and an acid circulating pump, the flue gas side outlet of the economizer 3A is connected with the flue gas inlet of the low-temperature heat recovery absorption tower, the flue gas outlet of the low-temperature heat recovery absorption tower is connected with the flue gas inlet of the flue gas heater, the flue gas outlet of the flue gas heater is connected with the second inlet of the low-temperature heat exchanger, the second outlet of the low-temperature heat exchanger is connected with the second inlet of the high-temperature heat exchanger, the second outlet of the high-temperature heat exchanger is connected with the fourth inlet of the converter, the fourth outlet of the converter is connected with the flue gas side inlet of the superheater 4A, the flue gas side outlet of the superheater 4A is connected with the flue gas side inlet of the economizer 4B, the flue gas side outlet of the economizer 4B is connected with the flue gas side inlet of the economizer 4A, the flue gas side outlet of the economizer 4A is connected with the secondary absorption unit, the secondary absorption unit comprises a secondary absorption tower and a secondary absorption acid tank, the flue gas side outlet of the economizer 4A is connected with the secondary absorption tower, the acid side outlet of the secondary absorption tower is connected with the inlet of the secondary absorption acid tank, the outlet of the secondary absorption acid tank is connected with the inlet of the finished acid cooler, the outlet of the finished acid cooler is the finished acid.

[0009] The flue gas heater comprises a flue gas heater A and a flue gas heater B, the acid side outlet of the low-temperature heat recovery absorption tower is divided into several paths and connected with the acid side inlets of the high-pressure heater, the flue gas heater B and the air heater respectively, the acid side outlets of the high-pressure heater, the flue gas heater B and the air heater are gathered into two paths and connected with the inlet of the low-temperature heat recovery absorption tower diluter and the acid side inlet of the flue gas heater A respectively, the outlet of the low-temperature heat recovery absorption tower diluter is connected with the low-temperature heat recovery absorption tower, the acid side outlet of the flue gas heater A is connected with the acid side inlet of the preheater, the acid side outlet of the preheater is connected with the secondary absorption unit and the drying unit respectively.

[0010] Compared with the prior art, the acid temperature of the low-temperature heat recovery system is improved in the existing sulfuric acid production device, heat is transferred, high-pressure steam is produced, low-pressure steam is no longer produced, the low-pressure steam system is cancelled, and the system is simplified. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 is a schematic diagram of the smoke and acid system in the sulfuric acid production process of the utility model.

[0012] Figure 2 is a schematic diagram of the water and steam system in the sulfuric acid production process of the utility model.

[0013] Referring to Figures 1 to 2, wherein 1-1 is an air filter, 1-2 is a drying tower, 1-3 is a main fan, 1-4 is an air heater, 1-5 is a sulfur incinerator, 1-6 is a waste heat boiler, 1-7 is a converter, 1-8 is a high-temperature superheater 1B, 1-9 is a hot heat exchanger, 1-10 is a cold heat exchanger, 1-11 is a coal economizer 3B, 1-12 is a coal economizer 3A, 1-13 is a low-temperature heat recovery absorption tower, 1-14 is a flue gas heater, 1-14-1 is a flue gas heater A, 1-14-2 is a flue gas heater B, 1-15 is a superheater 4A, 1-16 is a coal economizer 4B, 1-17 is a coal economizer 4A, 1-18 is a secondary absorption tower, 1-19 is a secondary absorption acid pump tank, 1-20 is a secondary absorption acid cooler, 1-21 is a finished acid cooler, 1-22 is a finished acid, 1-23 is an acid circulating pump, 1-24 is a high-pressure heater, 1-25 is a low-temperature heat recovery absorption tower diluter, 1-26 is a preheater, 1-27 is a dry acid pump tank, 1-28 is a dry acid cooler, 1-29 is desalted water (0.4Mpa), 1-30 is a deaerator, 1-31 is a continuous blowdown expander, 1-32 is a periodic blowdown expander, 1-34 is a vent port, 1-35 is a blowdown port, 1-36 is low-pressure steam, 1-37 is a boiler feed water pump, 1-38 is a boiler chemical feeding device, 1-39 is high-pressure steam, 1-40 is liquid sulfur, 1-41 is air, 1-42 is a tail suction device, 1-43 is a pump tank dilution water, 1-44 is HRS dilution water, and the numbers at the rhombus indicate the direction of the smoke, acid, water and steam in the sulfuric acid production process of the utility model. DETAILED DESCRIPTION

[0014] The utility model will be further described below with reference to the drawings. Example 1

[0015] As shown in Figures 1 to 2, in the heat energy utilization device for producing high-pressure steam in the sulfuric acid production of the embodiment, the low-temperature heat recovery absorption tower 1-13 increases the temperature of the high-temperature sulfuric acid in the lower tower, the temperature of the high-temperature sulfuric acid is 240-280℃, the high-temperature sulfuric acid has sufficient temperature difference, and can transfer SO 3The reaction heat of the reaction of sulfuric acid and water is all transferred to the high-pressure steam system, and all high-pressure steam is output, and no low-pressure steam is generated.

[0016] The high-temperature sulfuric acid of the lower tower of the low-temperature heat recovery absorption tower 1-13 is used as a direct or indirect heat source of the high-pressure heater 1-24, the flue gas heater 1-14, and the air heater 1-4.

[0017] The air heater 1-4 heats the air to be incinerated, and the air is mixed with sulfur after being heated and is incinerated to provide heat for the high-pressure steam system.

[0018] The flue gas heater 1-14 heats the flue gas from the low-temperature heat recovery absorption tower 1-13, and the flue gas from the low-temperature heat recovery absorption tower 1-13 is heated and enters the cold-heat heat exchanger 1-10 to exchange heat with the flue gas on the other side of the cold-heat heat exchanger. The heat of the flue gas at the outlet of the other side of the cold-heat heat exchanger 1-10 is transferred to the high-pressure steam system through the economizer 3A1-12 and the economizer 3B1-11.

[0019] The high-pressure heater 1-24 heats the feed water from the economizer 3A1-12 and the economizer 4A1-17 in the high-pressure steam system. The heated water enters the economizer 3B1-11 and the economizer 4B1-16 in the high-pressure steam system again to be heated. The heated water (serial number 118) also passes through the heating of the waste heat boiler 1-6, the superheater 4A1-15, and the superheater 1B1-8 to obtain high-pressure steam (serial number 121). The flue side inlet and outlet of the waste heat boiler 1-6 are arranged between the incineration unit and the conversion unit. The superheater 4A is arranged between the conversion unit and the secondary absorption unit. The superheater 1B is arranged in the conversion unit.

[0020] The temperature of the sulfuric acid of the lower tower of the low-temperature heat recovery absorption tower 1-13 is 240-280℃. The air heater 1-4 heats the air entering the incineration unit to heat the air from 60~130℃ to 220~260℃. The flue gas heater 1-14 heats the flue gas from the low-temperature heat recovery absorption tower 1-13 to heat the flue gas from 70~90℃ to 200~250℃ and enter the cold-heat heat exchanger 1-10. The high-pressure heater 1-24 heats the high-pressure feed water entering the economizer 3A1-12 and the economizer 4A1-17 to heat the high-pressure feed water from 104℃~170℃ to 200~260℃.

[0021] Temperature monitoring points and control valves are arranged after the low-temperature heat recovery absorption tower 1-13, the air heater 1-4, the flue gas heater 1-14, and the high-pressure heater 1-24. The amount of material entering the equipment is adjusted according to the set temperature parameters to control the temperature.

[0022] The materials in contact with high-temperature sulfuric acid in the low-temperature heat recovery absorption tower 1-13, the air heater 1-4, the flue gas heater 1-14, and the high-pressure heater 1-24 are selected from acid-resistant stainless steel, and the materials in contact with hot water and steam are selected from carbon steel.

[0023] The sulfuric acid production process includes but is not limited to sulfur-burning sulfuric acid production, pyrite-burning sulfuric acid production, and smelting flue gas-burning sulfuric acid production.

[0024] In the sulfuric acid production, the air is filtered through the air filter 1-1, the filtered air is dried in the drying tower 1-2, then the dried air is pressurized by the fan 1-3 and heated by the air heater 1-4, and then enters the sulfur-burning furnace 1-5 to burn and react with liquid sulfur, generating high-temperature flue gas containing SO2, which enters the waste heat boiler 1-6 to transfer the high-temperature heat in the flue gas to the high-pressure steam system, and generate high-pressure steam through the high-pressure feed water in the waste heat boiler 1-6, after the flue gas containing SO2 comes out of the waste heat boiler 1-6, it enters the converter 1-7 for catalytic oxidation, the flue gas after the first catalytic oxidation comes out of the first stage of the converter and enters the superheater 1B 1-8 to transfer the heat to the high-pressure steam in the superheater 1B, then the flue gas enters the second stage of the converter 1-7 after being cooled, and is catalytically oxidized again, the flue gas after the second catalytic oxidation comes out of the second stage of the converter and enters the hot heat exchanger 1-9 to transfer the heat to the flue gas on the other side of the hot heat exchanger 1-9, the cooled flue gas enters the converter 1-7 for the third time for catalytic oxidation, the flue gas after the third catalytic oxidation comes out of the third stage of the converter 1-7 and passes through the cold heat exchanger 1-10, the economizer 3A, and the economizer 3B, the heat in the flue gas is transferred to the high-pressure feed water passing through the economizer 3A and the economizer 3B, the cooled flue gas enters the low-temperature heat recovery absorption tower 1-13 for SO3 absorption, the flue gas after the low-temperature heat recovery absorption tower 1-13 passes through the flue gas heater 1-14, the cold heat exchanger 1-10, and the hot heat exchanger 1-9, and then enters the fourth stage of the converter 1-7 for the fourth time for catalytic oxidation, the flue gas after the fourth catalytic oxidation passes through the superheater 4A, the economizer 4B, and the economizer 4A to transfer the high-temperature heat in the flue gas to the high-pressure steam and feed water passing through the superheater 4A, the economizer 4B, and the economizer 4A, and then enters the second absorption tower 1-18 for the second SO3 absorption.

[0025] The high-temperature sulfuric acid after the low-temperature heat recovery absorption tower 1-13 is divided into two paths after passing through the air heater 1-4, the flue gas heater 1-14, and the high-pressure heater 1-24, one path enters the preheater and then enters the second absorption acid pump tank 1-19, and then passes through the finished acid cooler 1-21 to obtain the finished acid 1-22, and the other path of the high-temperature sulfuric acid passes through the low-temperature heat recovery absorption tower diluter 1-25, is diluted by water and serial acid, and then returns to the low-temperature heat recovery absorption tower 1-13 for repeated absorption process.

[0026] The acid side outlet of the low-temperature heat recovery absorption tower 1-13 is connected to the acid side inlet of the high-pressure heater 1-24, the flue gas heater 1-14 and the air heater 1-4 through the acid circulating pump 1-23, respectively; the acid side outlets of the high-pressure heater 1-24, the flue gas heater 1-14 and the air heater 1-4 are connected to the inlet of the low-temperature heat recovery absorption tower diluter 1-25 after being converged, and the outlet of the low-temperature heat recovery absorption tower diluter 1-25 is connected to the low-temperature heat recovery absorption tower 1-13. The acid side outlet of the flue gas heater 1-14 is connected to the acid side inlet of the preheater 1-26, and the acid side outlet of the preheater 1-26 is connected to the secondary absorption unit and the drying unit, respectively.

[0027] The drying unit includes, but is not limited to, an air filter 1-1, a drying tower 1-2, one end of the air filter 1-1 being connected to an air source, the other end of the air filter 1-1 being connected to the drying tower 1-2, the outlet of the drying tower 1-2 being connected to the inlet of a fan 1-3, the outlet of the fan 1-3 being connected to a burning unit through an air heater 1-4; the burning unit includes, but is not limited to, a sulfur burning furnace 1-5, a waste heat boiler 1-6, the outlet of the main fan 1-3, a liquid sulfur source being connected to the inlet of the sulfur burning furnace 1-5, the outlet of the sulfur burning furnace 1-5 being connected to the flue gas side inlet of the waste heat boiler 1-6, the flue gas side outlet of the waste heat boiler 1-6 being connected to a conversion unit, the conversion unit including, but not limited to, a converter 1-7, a hot heat exchanger 1-9, a cold heat exchanger 1-10, the flue gas side outlet of the waste heat boiler 1-6 being connected to the inlet of the first stage of the converter 1-7, the outlet of the first stage of the converter 1-7 being connected to the flue gas side inlet of a superheater 1B1-8, the flue gas side outlet of the superheater 1B being connected to the inlet of the second stage of the converter 1-7, the outlet of the second stage of the converter 1-7 being connected to the first inlet of the hot heat exchanger 1-9, the first outlet of the hot heat exchanger 1-9 being connected to the inlet of the third stage of the converter 1-7, the third stage outlet of the converter 1-7 being connected to the first inlet of the cold heat exchanger 1-10, the first outlet of the cold heat exchanger 1-10 being connected to the flue gas side inlet of an economizer 3B, the flue gas side inlet of the economizer 3B being connected to the flue gas side inlet of an economizer 3A, the flue gas side outlet of the economizer 3A being connected to a primary absorption unit, the primary absorption unit including, but not limited to, a low-temperature heat recovery absorption tower 1-13, an acid circulating pump 1-23, the flue gas side outlet of the economizer 3A being connected to the flue gas inlet of the low-temperature heat recovery absorption tower 1-13, the flue gas outlet of the low-temperature heat recovery absorption tower 1-13 being connected to the flue gas inlet of a flue gas heater 1-14, the flue gas outlet of the flue gas heater 1-14 being connected to the second inlet of the cold heat exchanger 1-10, the second outlet of the cold heat exchanger 1-10 being connected to the second inlet of the hot heat exchanger 1-9, the second outlet of the hot heat exchanger 1-9 being connected to the fourth stage inlet of the converter 1-7, the fourth stage outlet of the converter 1-7 being connected to the flue gas side inlet of a superheater 4A, the flue gas side outlet of the superheater 4A being connected to the flue gas side inlet of an economizer 4B, the flue gas side outlet of the economizer 4B being connected to the flue gas side inlet of the economizer 4A, the flue gas side outlet of the economizer 4A being connected to a secondary absorption unit, the secondary absorption unit including, but not limited to, a secondary absorption tower 1-18, a secondary absorption acid pump tank 1-19, the flue gas side outlet of the economizer 4A being connected to the secondary absorption tower 1-18, the acid side outlet of the secondary absorption tower 1-18 being connected to the inlet of the secondary absorption acid pump tank 1-19, the acid outlet of the secondary absorption acid pump tank 1-19 being connected to the inlet of a finished acid cooler 1-21, the outlet of the finished acid cooler 1-21 obtaining finished acid.

[0028] In the high-pressure steam system, the water side inlet of the preheater 1-26 is connected to a desalted water source, the water side outlet of the preheater 1-26 is connected to the inlet of the deaerator 1-30, the outlet of the deaerator 1-30 is connected to the boiler dosing device 1-38, the water side inlet of the economizer 3A, the water side inlet of the economizer 4A, and the dilution water pipeline 1-32 of the diluter through the boiler feed water pump 1-37, respectively; the water side outlet of the economizer 3A and the water side outlet of the economizer 4A are merged into one, and are jointly connected to the water side inlet of the high-pressure heater 1-24, the water side outlet of the high-pressure heater 1-24 is divided into two, and is connected to the water side inlet of the economizer 3B and the water side inlet of the economizer 4B, respectively, the water side outlet of the economizer 3B and the water side outlet of the economizer 4B are merged into one, and are jointly connected to the water side inlet of the waste heat boiler 1-6, the steam side outlet of the waste heat boiler 1-6 is connected to the steam side inlet of the superheater 4A, the steam side outlet of the superheater 4A is connected to the steam side inlet of the superheater 1B, and the steam side outlet of the superheater 1B produces high-pressure steam 121.

[0029] The acid side outlet of the preheater 1-26 is connected to the inlet of the dry acid pump tank 1-27 and the inlet of the double absorption acid pump tank 1-19, respectively, the outlet of the dry acid pump tank 1-27 is connected to the inlet of the double absorption acid pump tank 1-19 and the inlet of the low-temperature heat recovery absorption tower diluter 1-25, respectively, the outlet of the double absorption acid pump tank 1-19 is connected to the inlet of the double absorption acid cooler 1-20, and the outlet of the double absorption acid cooler 1-20 is connected to the inlet of the low-temperature heat recovery absorption tower 1-13 and the inlet of the double absorption tower 1-18, respectively.

[0030] The outlet of the dry acid pump tank 1-27 is also connected to the inlet of the dry acid cooler 1-28, the outlet of the dry acid cooler 1-28 is connected to the acid inlet of the drying tower 1-2, and the acid outlet of the drying tower 1-2 is connected to the dry acid pump tank 1-27.

[0031] In this embodiment, the low-temperature heat recovery absorption tower 1-13 is raised from about 200°C in the traditional low-temperature heat recovery system to 220-260°C through high-temperature acid circulation (serial number 72), and the sulfuric acid temperature of the lower tower (serial number 63) is changed from less than 230°C in the traditional process to 240-280°C.

[0032] The air heater 1-4 heats the air entering the sulfur incinerator 1-5 from 60-130°C to 220-260°C, the heated air enters the sulfur incinerator 1-5, the flue gas after the combustion reaction enters the waste heat boiler 1-6, and the high-temperature heat in the flue gas is transferred to the high-pressure steam system in the water vapor of the waste heat boiler 1-6 (i.e. serial number 118 in FIG. 2), to generate more high-pressure steam.

[0033] The flue gas heater 1-14 heats the flue gas (No. 18) from the low-temperature heat recovery absorption tower 1-13 from 70~90℃ to 200~250℃, and the heated flue gas (No. 20) enters the cold-heat heat exchanger 1-10 to exchange heat with the flue gas (No. 14) from the third outlet of the converter 1-7 to further heat to about 330℃ (No. 21), and then enters the hot-heat heat exchanger 1-9 to exchange heat, and the flue gas (No. 22) meeting the process requirements enters the fourth section of the converter. The flue gas (No. 14) from the third outlet of the converter 1-7 is at a temperature of 450~470℃, and the temperature of the flue gas (No. 15) after heat exchange in the cold-heat heat exchanger 1-10 is about 310~350℃, and in the traditional process, the temperature at this point is usually about 250~280℃, which is 60~100℃ higher. The flue gas (No. 20) heated by the flue gas heater reduces the heat consumed by the flue gas (No. 15) from the cold-heat heat exchanger, and heats the high-pressure hot water through the economizer 3A and the economizer 3B. After the improvement of the utility model, the heat of the part which is higher than the temperature in the traditional way is the heat transferred and utilized from the low-temperature heat source, and this part of heat is absorbed and utilized through the economizer 3A and the economizer 3B to generate more high-pressure steam.

[0034] In specific use, the source of the heating medium in the air heater and the flue gas heater is one or more of the high-temperature sulfuric acid, the high-pressure hot water, the high-pressure steam and the external heat source generated in the sulfuric acid production process.

[0035] The heat source of the high-pressure heater is the high-temperature sulfuric acid generated by the low-temperature heat recovery absorption tower, which enters the heat source medium inlet of the high-pressure heater to exchange heat with the boiler feed water, and then flows out from the heat source medium outlet of the high-pressure heater.

[0036] The high-pressure heater 1-24 heats the boiler feed water (No. 112) from the economizer 3A and the economizer 4A from 104℃~170℃ to 200~260℃, and then enters the economizer 3B and the economizer 4B, or enters the economizer 3B and the economizer 4B after being used as the heat source of the air heater and the flue gas heater. The temperature and the heat of the boiler feed water to the economizer are improved, and finally the high-pressure steam production is improved. Example Two

[0037] This example only illustrates the differences from Example One, and the same parts will not be repeatedly described. In this example, the flue gas heater 1-14 includes a flue gas heater A and a flue gas heater B, and the high-temperature sulfuric acid from the lower tower of the low-temperature heat recovery absorption tower 1-13 enters the high-pressure heater 1-24, the flue gas heater B and the air heater 1-4 respectively, and the temperature of the sulfuric acid from the high-pressure heater 1-24, the flue gas heater B and the air heater 1-4 is reduced, and then the sulfuric acid enters the flue gas heater A to provide heat, and the flue gas heater A and the flue gas heater B heat the flue gas from the low-temperature heat recovery absorption tower 1-13 twice.

[0038] The flue gas from the low-temperature heat recovery absorption tower 1-13 is heated by the flue gas heater A for the first time, and the flue gas is heated from 70-90 DEG C to 150+ / -10 DEG C, and then the flue gas is heated by the flue gas heater B for the second time, and the flue gas is heated to 200-250 DEG C, and then the flue gas enters the cold-heat heat exchanger 1-10.

[0039] The acid side outlet of the low-temperature heat recovery absorption tower 1-13 is divided into several paths, and is connected with the acid side inlets of the high-pressure heater 1-24, the flue gas heater B and the air heater 1-4 respectively, the acid side outlets of the high-pressure heater 1-24, the flue gas heater B and the air heater 1-4 are gathered into two paths, and are connected with the inlets of the low-temperature heat recovery absorption tower diluter 1-25 and the acid side inlet of the flue gas heater A respectively, the outlet of the low-temperature heat recovery absorption tower diluter 1-25 is connected with the low-temperature heat recovery absorption tower 1-13, the acid side outlet of the flue gas heater A is connected with the acid side inlet of the preheater 1-26, and the acid side outlet of the preheater 1-26 is connected with the secondary absorption unit and the drying unit respectively.

[0040] The utility model discloses the low-temperature heat recovery absorption tower's lower tower acid temperature is improved, and is not more than 230 DEG C, promotes 240-280 DEG C. And through air heater, flue gas heater, high pressure heater, the heat in high temperature acid is transmitted to high pressure steam system, cancels the low pressure steam part in traditional low-temperature heat recovery system, reaches the purpose of all production high pressure steam, significantly improves the output of high pressure steam, maximizes the economic benefit.

Claims

1. A heat energy utilization device for producing high pressure steam in the production of sulfuric acid, comprising a low temperature heat recovery absorption tower, characterized in that: The high-temperature sulfuric acid temperature of the low-temperature heat recovery absorption tower (1-13) is 240-280℃, the acid side outlet of the low-temperature heat recovery absorption tower (1-13) is divided into several paths, and is connected with the acid side inlet of the high-pressure heater (1-24), the flue gas heater (1-14) and the air heater (1-4) respectively; the acid side outlets of the high-pressure heater (1-24), the flue gas heater (1-14) and the air heater (1-4) are gathered and connected with the inlet of the low-temperature heat recovery absorption tower diluter (1-25), the outlet of the low-temperature heat recovery absorption tower diluter (1-25) is connected with the low-temperature heat recovery absorption tower (1-13), and the acid side outlet of the flue gas heater (1-14) is also connected with the acid side inlet of the preheater (1-26), and the acid side outlet of the preheater (1-26) is connected with the secondary absorption unit and the drying unit respectively.

2. A device for utilizing heat energy for producing high pressure steam in the production of sulfuric acid according to claim 1, characterized in that: The air temperature at the inlet of the air heater (1-4) is 60-130℃, the air temperature at the outlet of the air heater (1-4) is 220-260℃; the flue gas temperature at the inlet of the flue gas heater (1-14) is 70-90℃, the flue gas temperature at the inlet of the flue gas heater (1-14) is 200-250℃; the steam temperature at the inlet of the high-pressure heater (1-24) is 104-170℃, and the steam temperature at the outlet of the high-pressure heater (1-24) is 200-260℃.

3. A device for utilizing heat energy for producing high pressure steam in the production of sulfuric acid according to claim 1, characterized in that: The water side inlet of the preheater (1-26) is connected with the high-pressure steam system, in the high-pressure steam system, the water side inlet of the preheater (1-26) is connected with the desalted water source, the water side outlet of the preheater (1-26) is connected with the inlet of the deaerator (1-30), the outlet of the deaerator (1-30) is connected with the boiler dosing device (1-38), the water side inlet of the economizer 3A (1-12), the water side inlet of the economizer 4A (1-17) and the diluter dilution water pipeline (1-32) through the boiler feed water pump (1-37) respectively; the water side outlet of the economizer 3A (1-12) and the water side outlet of the economizer 4A (1-17) are gathered into one path and are connected with the water side inlet of the high-pressure heater (1-24) together, the water side outlet of the high-pressure heater (1-24) is divided into two paths and is connected with the water side inlet of the economizer 3B (1-11) and the water side inlet of the economizer 4B (1-16) respectively, the water side outlet of the economizer 3B (1-11) and the water side outlet of the economizer 4B (1-16) are gathered into one path and are connected with the water side inlet of the waste heat boiler (1-6) together, the steam side outlet of the waste heat boiler (1-6) is connected with the steam side inlet of the superheater 4A (1-15), the steam side outlet of the superheater 4A (1-15) is connected with the steam side inlet of the superheater 1B (1-8), and the steam side outlet of the superheater 1B (1-8) produces high-pressure steam (121).

4. A device for utilizing heat energy for producing high pressure steam in the production of sulfuric acid according to claim 1, characterized in that: The drying unit comprises an air filter (1-1), a drying tower (1-2), one end of the air filter (1-1) is connected with an air source, the other end of the air filter (1-1) is connected with the drying tower (1-2), the outlet of the drying tower (1-2) is connected with the inlet of a fan (1-3), and the outlet of the fan (1-3) is connected with a burning unit through an air heater (1-4).The incineration unit comprises a sulfur incinerator (1-5), a waste heat boiler (1-6), an outlet of a main fan (1-3), an inlet of the sulfur incinerator (1-5) connected with a liquid sulfur source, a flue gas side inlet of the waste heat boiler (1-6) connected with an outlet of the sulfur incinerator (1-5), and a flue gas side outlet of the waste heat boiler (1-6) connected with a conversion unit. The conversion unit comprises a converter (1-7), a high-temperature heat exchanger (1-9), and a low-temperature heat exchanger (1-10). The flue gas side outlet of the waste heat boiler (1-6) is connected with a first stage inlet of the converter (1-7). A flue gas side outlet of a superheater 1B (1-8) is connected with a second stage inlet of the converter (1-7). A flue gas side outlet of the superheater 1B (1-8) is connected with a third stage inlet of the converter (1-7). A first outlet of the high-temperature heat exchanger (1-9) is connected with a fourth stage inlet of the converter (1-7). A first outlet of the low-temperature heat exchanger (1-10) is connected with a flue gas side inlet of an economizer 3B (1-11). A flue gas side inlet of the economizer 3B (1-11) is connected with a flue gas side inlet of an economizer 3A (1-12). A flue gas side outlet of the economizer 3A (1-12) is connected with a primary absorption unit. The primary absorption unit comprises a low-temperature heat recovery absorption tower (1-13) and an acid circulating pump (1-23). A flue gas inlet of the low-temperature heat recovery absorption tower (1-13) is connected with the flue gas side outlet of the economizer 3A (1-12). A flue gas outlet of the low-temperature heat recovery absorption tower (1-13) is connected with a flue gas inlet of a flue gas heater (1-14). A flue gas outlet of the flue gas heater (1-14) is connected with a second inlet of the low-temperature heat exchanger (1-10). A second outlet of the low-temperature heat exchanger (1-10) is connected with a second inlet of the high-temperature heat exchanger (1-9). A second outlet of the high-temperature heat exchanger (1-9) is connected with a fifth stage inlet of the converter (1-7). A flue gas side inlet of a superheater 4A (1-15) is connected with a fifth stage outlet of the converter (1-7). A flue gas side outlet of the superheater 4A (1-15) is connected with a flue gas side inlet of an economizer 4B (1-16). A flue gas side outlet of the economizer 4B (1-16) is connected with a flue gas side inlet of an economizer 4A (1-17). A flue gas side outlet of the economizer 4A (1-17) is connected with a secondary absorption unit. The secondary absorption unit comprises a secondary absorption tower (1-18) and a secondary absorption acid pump tank (1-19). The flue gas side outlet of the economizer 4A (1-17) is connected with the secondary absorption tower (1-18). An acid side outlet of the secondary absorption tower (1-18) is connected with an inlet of the secondary absorption acid pump tank (1-19). An acid outlet of the secondary absorption acid pump tank (1-19) is connected with an inlet of a finished acid cooler (1-21). An outlet of the finished acid cooler (1-21) obtains finished acid.

5. A device for utilizing heat energy for producing high pressure steam in the production of sulfuric acid according to claim 1, characterized in that: The flue gas heater (1-14) comprises a flue gas heater A (1-14-1), a flue gas heater B (1-14-2), and a plurality of paths of the acid side outlet of the low-temperature heat recovery absorption tower (1-13) connected with the acid side inlet of the high-pressure heater (1-24), the flue gas heater B (1-14-2), and the air heater (1-4), respectively, the acid side outlets of the high-pressure heater (1-24), the flue gas heater B (1-14-2), and the air heater (1-4) converging into two paths connected with the inlet of the low-temperature heat recovery absorption tower diluter (1-25) and the acid side inlet of the flue gas heater A (1-14-1), respectively, the outlet of the low-temperature heat recovery absorption tower diluter (1-25) connected with the low-temperature heat recovery absorption tower (1-13), the acid side outlet of the flue gas heater A (1-14-1) connected with the acid side inlet of the preheater (1-26), and the acid side outlet of the preheater (1-26) connected with the secondary absorption unit and the drying unit, respectively.

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