Phenolic water recovery system of two-section type gas producer

Abstract

The utility model discloses a phenol water recovery system of a two-section type gas producer. The phenol water recovery system comprises a gas producer, a phenol water superheater, a phenol water boiler and a gas cooler. According to the phenol water recovery system of the gas producer at the two ends, the phenol water in the gas can be recovered, the sensible heat of the gas at the lower section is used for heating the phenol water to form phenol water vapor, the phenol water vapor and a gasifying agent are heated together, and the phenol water vapor is introduced into the gas producer through the first gasifying agent inlet and the second gasifying agent inlet; the superheat degree of water vapor in the gasifying agent is high, so that phenol is prevented from being brought into ash slag through condensation of the water vapor, the ash slag is prevented from being changed into hazardous waste, the problem of wastewater treatment is thoroughly solved, sensible heat of lower-section coal gas is fully utilized, energy waste is avoided, and the heat efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas furnaces, and more specifically, to a phenol water recovery system for a two-stage gasifier. Background Art

[0002] A two-stage gasifier uses fixed-bed gasification to produce coal gas. It typically consists of an upper gas stage and a lower gas stage. The upper gas, produced from the coal pyrolysis and drying area, contains tar and phenols. The purification process for this upper gas produces a significant amount of phenol-containing wastewater. The lower gas, produced from the coal combustion and gasification area, is generally tar- and phenol-free. However, fluctuations in the gasifier's operating conditions may result in the lower gas containing tar and phenols.

[0003] Existing gasifiers heat phenol-containing water, vaporize it into steam, and then add the steam to a gasifying agent to react in the gasifier, thereby recovering the phenol water. However, during the phenol water recovery process, the phenol-containing steam enters the gasifier, meets the low-temperature gasifying agent, and condenses upon cooling. The condensate of the phenol steam remains in the ash in the gasifier, turning the ash into hazardous waste. This ash is generally red in color, transforming water pollution into solid waste pollution, and does not solve the fundamental problem of phenol water recovery. In addition, the temperature of the lower-stage gas is generally higher, and the purification and cooling of the lower-stage gas wastefully consumes the sensible heat of the gas, resulting in low system thermal efficiency. Utility Model Content

[0004] An object of the present invention is to solve at least the above problems and to provide at least the advantages to be described below.

[0005] Another object of the present invention is to provide a phenol water recovery system for a two-stage coal gasifier, which can solve the technical defect that the prior art cannot effectively solve the fundamental problem of phenol water recovery.

[0006] In order to achieve these purposes and other advantages according to the present invention, a phenol water recovery system for a two-stage coal gasifier is provided, comprising:

[0007] A gasifier (100) is provided with a feed port (110) at the top and a first gasifying agent inlet (120) at the bottom for introducing oxygen-containing gas into the gasifier (100); an upper gas outlet (140), at least one lower gas outlet (150), and at least one second gasifying agent inlet (170) are provided on one side of the gasifier from top to bottom; the upper gas outlet is connected to a gas processing mechanism, and the gas processing mechanism is provided with a phenol water recovery outlet and an upper gas discharge outlet;

[0008] A phenol water superheater (300) is provided with a phenol water superheater gas inlet (310) communicating with the lower gas outlet, a phenol water superheater gas outlet (320), a phenol water steam inlet (330) of the phenol water superheater, and a phenol water steam outlet (340) of the phenol water superheater communicating with the first gasifying agent inlet (120) and the second gasifying agent inlet (170);

[0009] The phenol water boiler (400) is provided with a phenol water inlet (430) of the phenol water boiler connected to the phenol water recovery outlet, a coal gas outlet (420) of the phenol water boiler, a coal gas inlet (410) of the phenol water boiler connected to the coal gas outlet (320) of the phenol water superheater, and a phenol water steam outlet (440) of the phenol water boiler connected to the phenol water steam inlet (330) of the phenol water superheater.

[0010] Preferably, the phenol water recovery system of the two-stage gasifier, the gas cooler (700), is provided with a gas inlet (710) of the gas cooler connected to the gas outlet (420) of the phenol water boiler, and a lower gas outlet (720).

[0011] Preferably, the phenol water recovery system of the two-stage gasifier further comprises a cyclone separator (200), wherein an upper portion of one side of the cyclone separator is provided with a gas inlet (210) of the cyclone separator connected to the gas outlet (150) of the lower stage, a top portion is provided with a gas outlet (220) of the cyclone separator connected to the gas inlet (310) of the phenol water superheater, and a bottom portion is provided with a fly ash discharge outlet (230).

[0012] Preferably, the phenol water recovery system of the two-stage gasifier further comprises:

[0013] An air preheater (500) is provided with an air preheater gas inlet (510) connected to the gas outlet (420) of the phenol water boiler, an air preheater gas outlet (520), an oxygen-containing gas inlet (530), and an oxygen-containing gas outlet (540) connected to the first gasifying agent inlet (120) and the second gasifying agent inlet (170);

[0014] The phenol water preheater (600) is provided with a phenol water preheater gas inlet (610) connected to the gas outlet (520) of the air preheater, a phenol water preheater gas outlet (620) connected to the gas inlet (710) of the gas cooler, a phenol water inlet (630), and a phenol water outlet (640) of the phenol water preheater connected to the phenol water inlet (430) of the phenol water boiler.

[0015] Preferably, the phenol water recovery system of the two-stage gasifier, the phenol water boiler includes a phenol water steam generator (401) and a phenol water drum (402), the phenol water steam generator (401) is provided with a phenol water steam generator gas inlet (4011) connected to the phenol water superheater gas outlet (320), a phenol water steam generator gas outlet (4012) connected to the air preheater gas inlet (510), a phenol water steam generator gas outlet (4021) connected to the phenol water drum gas inlet (4022), and a phenol water steam generator gas outlet (4023) connected to the air preheater gas outlet (510). The phenol water steam drum (402) is provided with a phenol water steam outlet (4013) of the phenol water steam generator, a phenol water inlet (4014) of the phenol water steam generator connected to the phenol water outlet (640) of the phenol water preheater and the phenol water outlet (4022) of the phenol water steam drum; a phenol water steam outlet (4023) of the phenol water steam drum connected to the phenol water steam inlet (330) of the phenol water superheater, and a sewage outlet (4024); and a phenol water recovery outlet is connected to the phenol water inlet (4014) of the phenol water steam generator.

[0016] Preferably, in the phenol water recovery system of the two-stage gasifier, a grate (160) is provided in the gasifier (100), which is located below the second gasifier inlet (170); the bottom of the grate (160) is connected to the first gasifier inlet (120), and the top is provided with an air distribution port connected to the reaction furnace of the gasifier (100).

[0017] Preferably, in the phenol water recovery system of the two-stage gasifier, the grate includes a multi-layer structure stacked in sequence from bottom to top, the diameter of the multi-layer structure decreases in sequence from bottom to top, each layer of the structure is provided with air distribution ports, and the ventilation volume of the air distribution ports on the multi-layer structure decreases in sequence from top to bottom; the ventilation volume per unit area of ​​the air distribution ports on the topmost structure does not exceed 200% of the average ventilation volume per unit area, and the ventilation volume per unit area of ​​the air distribution ports on the bottommost structure is not less than 30% of the average ventilation volume per unit area.

[0018] Preferably, in the phenol water recovery system of the two-stage gasifier, at least one lower gas outlet has at least two outlets, and the multiple lower gas outlets are distributed at at least two different heights; each lower gas outlet is provided with a valve.

[0019] Preferably, in the phenol water recovery system of the two-stage gasifier, the air preheater (500) is a heat pipe heat exchanger.

[0020] Preferably, the phenol water recovery system of the two-stage gasifier, the gas processing mechanism includes an electric tar precipitator (800), a gas intercooler (900) and a phenol water pool (1000) connected in sequence; the gas inlet (810) of the electric tar precipitator is connected to the upper gas outlet (140), the gas outlet (820) of the electric tar precipitator is connected to the gas inlet (910) of the gas intercooler, the cooling medium in the gas intercooler (900) is cold water, an upper gas outlet (920) is provided in the middle of one side of the gas intercooler, and a phenol water outlet (930) of the gas intercooler connected to the phenol water inlet (1010) of the phenol water pool is provided at the lower part; the phenol water recovery outlet (1020) is provided on the phenol water pool, which is connected to the phenol water inlet (4014) of the phenol water steam generator.

[0021] The utility model has at least the following beneficial effects:

[0022] 1. The phenol water recovery system for the two-end coal gasifier provided by the utility model can recover the phenol water in the coal gas, and use the sensible heat of the lower section coal gas to heat the phenol water to form phenol water vapor, which is heated together with the gasifier and introduced into the coal gasifier through the first gasifier inlet and the second gasifier inlet, thereby realizing the recovery and utilization of the phenol water. The water vapor in the gasifier has a high superheat degree, which prevents the water vapor from condensing and bringing phenol into the ash, turning the ash into hazardous waste, and completely solving the problem of wastewater treatment. In addition, the sensible heat of the lower section coal gas is fully utilized to avoid energy waste and improve thermal efficiency.

[0023] 2. The utility model vaporizes phenol water to generate saturated steam, and further superheats the steam before mixing it with oxygen-containing gas and feeding it into the gasifier. The water vapor in the gasifying agent is highly superheated, which prevents the water vapor from condensing and bringing phenol into the ash, turning the ash into hazardous waste, and completely solving the problem of wastewater treatment.

[0024] 3. The utility model has multiple lower gas outlets, which are located at different heights of the gas furnace. The location of the lower gas outlet can be reasonably selected according to the operating conditions of the gas furnace, so that the gas temperature at the lower gas outlet is higher than 700°C, ensuring that the lower gas does not contain difficult-to-treat substances such as tar and phenols;

[0025] 4. The heat of the lower gas in the present invention is used to preheat the oxygen-containing gas, preheat the phenolic water, and heat the phenolic water to generate saturated steam and superheated steam, thereby recovering the sensible heat of the lower gas while reducing its temperature, resulting in high thermal efficiency. The present invention uses a cyclone separator to separate the lower gas from the solids and fly ash, thus avoiding clogging of the subsequent heat exchanger for the lower gas.

[0026] 5. The phenol water boiler of the present invention is provided with a steam drum and a phenol water steam generator, and a blowdown device is provided in the steam drum, so that impurities such as insoluble solids in the phenol water are discharged from the phenol water boiler through the blowdown device, thereby ensuring stable operation of the water system of the phenol water boiler;

[0027] 6. The utility model adopts a heat pipe heat exchanger for the heat exchange between the coal gas and the oxygen-containing gas, and uses the heat pipe as the intermediate medium for the heat exchange between the coal gas and the oxygen-containing gas, thereby avoiding the risk of combustion or explosion caused by leakage of the conventional heat exchanger and the contact between the coal gas and the oxygen-containing gas.

[0028] 7. Other advantages, objectives and features of the present invention will be reflected in part through the following description, and in part will be understood by those skilled in the art through research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 1 of the present utility model;

[0030] Figure 2 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 2 of the present utility model;

[0031] Figure 3 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 3 of the present utility model;

[0032] Figure 4 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 4 of the present utility model;

[0033] Figure 5 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 5 of the present utility model;

[0034] Figure 6 This is a schematic structural diagram of the phenol water recovery system of the two-stage gasifier described in Example 6 of the present utility model;

[0035] Explanation of reference numerals: gasifier (100), feeding port 110, first gasifying agent inlet (120), slag discharge port 130, upper gas outlet (140), lower gas outlet (150), grate (160), second gasifying agent inlet (170)

[0036] A cyclone separator (200), a coal gas inlet (210) of the cyclone separator, a coal gas outlet (220) of the cyclone separator, and a fly ash discharge outlet (230);

[0037] A phenol water superheater (300), a coal gas inlet (310) of the phenol water superheater, a coal gas outlet (320) of the phenol water superheater, a phenol water vapor inlet (330) of the phenol water superheater, and a phenol water vapor outlet (340) of the phenol water superheater;

[0038] A phenol water boiler (400), a gas inlet (410) of the phenol water boiler, a gas outlet (420) of the phenol water boiler, a phenol water inlet (430) of the phenol water boiler, a phenol water steam outlet (440) of the phenol water boiler, and a sewage outlet (450);

[0039] A phenol water vapor generator (401), a gas inlet (4011) of the phenol water vapor generator, a gas outlet (4012) of the phenol water vapor generator, a phenol water vapor outlet (4013) of the phenol water vapor generator, and a phenol water inlet (4014) of the phenol water vapor generator;

[0040] A phenol water vapor drum (402), a phenol water vapor inlet (4021) of the phenol water vapor drum, a phenol water outlet (4022) of the phenol water vapor drum, a phenol water vapor outlet (4023) of the phenol water vapor drum, and a sewage outlet (4024);

[0041] An air preheater (500), a gas inlet (510) of the air preheater, a gas outlet (520) of the air preheater, an oxygen-containing gas inlet (530), and an oxygen-containing gas outlet (540);

[0042] A phenol water preheater (600), a gas inlet (610) of the phenol water preheater, a gas outlet (620) of the phenol water preheater, a phenol water inlet (630) of the phenol water preheater, and a phenol water outlet (640) of the phenol water preheater;

[0043] A gas cooler (700), a gas inlet (710) of the gas cooler, and a lower gas outlet (720);

[0044] An electric tar collector (800), a gas inlet (810) of the electric tar collector, and a gas outlet (820) of the electric tar collector;

[0045] A gas intercooler (900), a gas inlet (910) of the gas intercooler, an upper gas outlet (920), and a phenol water outlet (930) of the gas intercooler;

[0046] A phenol water pool (1000), a phenol water inlet (1010) of the phenol water pool, and a phenol water recovery outlet (1020). DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments so that those skilled in the art can implement the invention with reference to the description.

[0048] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0049] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified.

[0050] In the description of the present invention, the terms "horizontal", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0051] Example 1

[0052] like Figure 1 As shown, the utility model provides a phenol water recovery system for a two-stage coal gasifier, which includes:

[0053] A gasifier (100) is provided with a feeding port (110) at the top and a first gasifying agent inlet (120) at the bottom for introducing oxygen-containing gas into the gasifier (100); one side of the gasifier is provided with an upper gas outlet (140), at least one lower gas outlet (150), and at least one second gasifying agent inlet (170) from top to bottom; the upper gas outlet is connected to a gas treatment mechanism, and the gas treatment mechanism is provided with a phenol water recovery outlet and an upper gas discharge outlet; the number of at least one lower gas outlet is at least two, and the multiple lower gas outlets are distributed at at least two different heights; each lower gas outlet is provided with a valve; according to the gas temperature of each lower gas outlet, one or more of the gas outlets with a gas outlet temperature greater than 700°C are selected to open the valve, thereby ensuring that the temperature of the lower gas discharged from the two-stage gasifier is greater than 700°C; Figure 1 As shown, the lower gas outlet is provided with three 151, 152, 153 from top to bottom;

[0054] A phenol water superheater (300) is provided with a phenol water superheater gas inlet (310) communicating with the lower gas outlet, a phenol water superheater gas outlet (320), a phenol water steam inlet (330) of the phenol water superheater, and a phenol water steam outlet (340) of the phenol water superheater communicating with the first gasifying agent inlet (120) and the second gasifying agent inlet (170);

[0055] The phenol water boiler (400) is provided with a phenol water inlet (430) of the phenol water boiler connected to the phenol water recovery outlet, a gas outlet (420) of the phenol water boiler, a gas inlet (410) of the phenol water boiler connected to the gas outlet (320) of the phenol water superheater, and a phenol water steam outlet (440) of the phenol water boiler connected to the phenol water steam inlet (330) of the phenol water superheater; the phenol water boiler (400) is also provided with a sewage outlet (450);

[0056] The gas cooler (700) is provided with a gas inlet (710) of the gas cooler connected to the gas outlet (420) of the phenol water boiler, and a lower gas outlet (720).

[0057] In the above technical solution, the present invention provides a phenol water recovery system for a two-stage coal gasifier, which includes a coal gasifier, which is provided with a feeding port (110) for adding raw coal, the upper coal gas in the coal gasifier is discharged through the upper coal gas outlet (140), and the lower coal gas is discharged through the lower coal gas outlet (150), and the gasifier is added to the coal gasifier through the first gasifier inlet (120) and the second gasifier inlet (170), the first gasifier inlet (120) is provided at the bottom, and the second gasifier inlet (170) is provided on the lower peripheral side, and the gasifier is added to the coal gasifier through the first gasifier inlet (120) and the second gasifier inlet (170). The gasifier is oxygen-containing gas, and before flowing into the first gasifier inlet and the second gasifier inlet, the gasifier is preheated to avoid condensation of phenol water vapor due to low temperature of the gasifier), and vertical airflow and horizontal airflow are formed, which strengthens the contact and mixing of the gasifier airflow and the solid raw material, and improves the gas-solid reaction rate; the upper section coal gas flows into the coal gas treatment mechanism through the upper section coal gas outlet (140), the coal gas is purified and cooled, and the phenol water obtained by cooling flows into the phenol water boiler (400) through the phenol water recovery outlet (phenol water from other sources can also be added to the phenol water boiler), the phenol water in the coal gas is recovered, and the lower section coal gas outlet (150) is connected to the phenol water superheater. The lower section of the coal gas is connected to the coal gas inlet (310) of the phenol water superheater (300), and the lower section of the coal gas undergoes heat exchange in the phenol water superheater (300), and the temperature of the lower section of the coal gas is reduced; the lower section of the coal gas enters the phenol water boiler through the coal gas outlet (320) of the phenol water superheater and the coal gas inlet (410) of the phenol water boiler, and undergoes heat exchange, and the temperature of the lower section of the coal gas is further reduced. The phenol water in the phenol water boiler (400) is heated and vaporized to form phenol water steam, and passes through the phenol water steam outlet (440) of the phenol water boiler and the phenol water steam inlet (330) of the phenol water superheater, and flows into the phenol water superheater (300). The phenol water in the phenol water superheater is saturated steam, and forms superheated steam under the heating effect of the lower section of the coal gas. The phenol water superheater After the hot steam is mixed with the oxygen-containing gas, it enters the two-stage gasifier through the first gasifying agent inlet (120) and the second gasifying agent inlet (170) as a gasifying agent. The phenol steam is decomposed into small molecular gases such as CO and H2 at high temperature. The oxygen-containing gas is oxygen, air, a mixture of oxygen and CO2, etc. (the lower stage gas is cooled and phenol water is recovered during the treatment process). After the cooling and phenol water recovery treatment, the lower stage gas continues to flow into the gas cooler through the gas outlet (420) of the phenol water boiler and the gas inlet (710) of the gas cooler. After being cooled to the target temperature, the lower stage gas is sent to the downstream process section through the lower stage gas outlet (720) of the gas cooler.

[0058] The phenol water recovery system of the two-end coal gasifier provided by the utility model can recover the phenol water in the coal gas, and use the sensible heat of the lower section coal gas to heat the phenol water to form phenol water vapor, which is heated together with the gasifier and introduced into the coal gasifier through the first gasifier inlet and the second gasifier inlet, thereby realizing the recovery and utilization of the phenol water. The water vapor in the gasifier has a high superheat degree, which avoids the condensation of water vapor and the introduction of phenol into ash and the conversion of ash into hazardous waste, thus completely solving the problem of wastewater treatment, and making full use of the sensible heat of the lower section coal gas, thereby avoiding energy waste and improving thermal efficiency.

[0059] Example 2

[0060] like Figure 2 As shown, based on Example 1, the phenol water recovery system of the two-stage gasifier further includes a cyclone separator (200), an upper portion of which is provided with a cyclone separator gas inlet (210) connected to the lower stage gas outlet (150), a top portion thereof is provided with a cyclone separator gas outlet (220) connected to the phenol water superheater gas inlet (310), and a bottom portion thereof is provided with a fly ash discharge outlet (230).

[0061] The lower section coal gas outlet (150) is connected to the cyclone separator (200) and then connected to the phenol water superheater (300); the lower section coal gas discharged from the lower section coal gas outlet (150) enters the cyclone separator through the coal gas inlet (210) of the cyclone separator, and the cyclone separator removes fly ash in the lower section coal gas to purify the lower section coal gas. The purified lower section coal gas that does not contain fly ash solid particles passes through the coal gas outlet (220) of the cyclone separator and enters the phenol water superheater (300) via the coal gas inlet (310) of the phenol water superheater; a fly ash discharge outlet (230) for discharging flyback particles is provided at the bottom of the cyclone separator (200).

[0062] Example 3

[0063] like Figure 3 As shown, based on Example 2, the phenol water recovery system of the two-stage gasifier further includes:

[0064] An air preheater (500) is provided with an air preheater gas inlet (510) connected to the gas outlet (420) of the phenol water boiler, an air preheater gas outlet (520), an oxygen-containing gas inlet (530), and an oxygen-containing gas outlet (540) connected to the first gasifying agent inlet (120); the air preheater (500) is a heat pipe heat exchanger;

[0065] The phenol water preheater (600) is provided with a phenol water preheater gas inlet (610) connected to the gas outlet (520) of the air preheater, a phenol water preheater gas outlet (620) connected to the gas inlet (710) of the gas cooler, a phenol water inlet (630) connected to the phenol water recovery outlet of the gas treatment mechanism, and a phenol water outlet (640) of the phenol water preheater connected to the phenol water inlet (430) of the phenol water boiler.

[0066] On the basis of Example 1, an air preheater and a phenol water preheater are provided to preheat the oxygen-containing gas and phenol water, thereby increasing the temperature of the oxygen-containing air and phenol water. Specifically, the lower section of coal gas discharged from the coal gas outlet (420) of the phenol water boiler passes through the coal gas inlet (510) of the air preheater, the coal gas outlet (520) of the air preheater, and the coal gas inlet (610) of the phenol water preheater in sequence, so that the sensible heat of the lower section of coal gas participates in the heat exchange in the air preheater and the phenol water preheater, further utilizing the heat of the lower section of coal gas and further reducing the temperature of the lower section of coal gas. The phenol water condensed in the process of treating the upper section of coal gas is combined with the additional phenol water. The phenol water inlet (630) of the phenol water preheater enters the interior of the phenol water preheater (600) for heating, and then flows into the phenol water boiler (400) through the phenol water outlet (640) of the phenol water preheater and the phenol water inlet (430) of the phenol water boiler; the oxygen-containing gas enters the air preheater (500) from the oxygen-containing gas inlet (530) of the air preheater, and the heated oxygen-containing gas merges with the superheated phenol water vapor discharged from the phenol water vapor outlet (340) of the phenol water superheater through the oxygen-containing gas outlet (540) of the air preheater, and then passes into the gasifier through the first gasifying agent inlet and the second gasifying agent inlet.

[0067] Example 4

[0068] like Figure 4 As shown, based on Example 3, the phenol water boiler (400) includes a phenol water steam generator (401) and a phenol water drum (402), the phenol water steam generator (401) is provided with a phenol water steam generator gas inlet (4011) connected to the phenol water superheater gas outlet (320), a phenol water steam generator gas outlet (4012) connected to the air preheater gas inlet (510), a phenol water steam generator phenol water steam outlet (4013) connected to the phenol water steam inlet (4021) of the phenol water drum, and a phenol water inlet (4014) of the phenol water steam generator connected to the phenol water outlet (640) of the phenol water preheater and the phenol water outlet (4022) of the phenol water drum; the phenol water drum (402) is provided with a phenol water steam drum phenol water steam outlet (4023) connected to the phenol water steam inlet (330) of the phenol water superheater and a sewage outlet (4024).

[0069] The phenol water heated by the phenol water preheater (600) flows into the phenol water steam generator (401) through the phenol water outlet (640) of the phenol water preheater and the phenol water inlet (4014) of the phenol water steam generator, and the phenol water steam is heated to generate phenol water steam. The phenol water steam flows into the phenol water steam drum through the phenol water steam outlet (4011) of the phenol water steam generator and the phenol water steam inlet (4021) of the phenol water steam drum. The steam-water mixture enters the phenol water steam drum, and phenol water saturated steam is separated in the phenol water steam drum. The phenol water saturated steam is The phenol water vapor outlet (4023) of the phenol water drum and the phenol water vapor inlet (330) of the phenol water superheater flow into the phenol water superheater (300). The liquid phenol water separated from the phenol water drum passes through the water separation outlet (4022) of the phenol water drum and the phenol water inlet (4014) of the phenol water steam generator, and is mixed with the phenol water sent to the phenol water boiler (the phenol water discharged from the phenol water outlet (640) of the phenol water preheater) and then returned to the phenol water steam generator. The waste from the phenol water drum is discharged through the sewage outlet (4024). The lower section of coal gas discharged from the coal gas outlet (320) of the phenol water superheater enters the phenol water steam generator (401) through the coal gas inlet (4011) of the phenol water steam generator, and the sensible heat of the lower section of coal gas is utilized again. After the lower section of coal gas participates in heat exchange in the steam generator (401), the temperature of the lower section of coal gas is further reduced, and then enters the air preheater (500) through the coal gas outlet (4012) of the phenol water steam generator and the coal gas inlet (510) of the air preheater.

[0070] Example 5

[0071] like Figure 5 As shown, based on Example 4, the phenol water recovery system of the two-stage gasifier is provided, wherein a grate (160) is provided in the gasifier (100), which is located below the second gasifying agent inlet (170), the bottom of the grate (160) is connected to the first gasifying agent inlet (120), and the top is provided with an air distribution port connected to the reaction furnace of the gasifier (100); the grate includes a multi-layer structure stacked from bottom to top, the diameter of the multi-layer structure decreases from bottom to top, each layer of the structure is provided with an air distribution port, and the ventilation volume of the air distribution port on the multi-layer structure decreases from top to bottom; the ventilation volume per unit area of ​​the air distribution port on the topmost structure does not exceed 200% of the average ventilation volume per unit area, and the ventilation volume per unit area of ​​the air distribution port on the bottommost structure is not less than 30% of the average ventilation volume per unit area. The ventilation volume per unit area is the ventilation volume of the corresponding air outlet Q / the corresponding air outlet area A1; the average ventilation volume per unit area is the total ventilation volume of the furnace Q / the total air outlet area of ​​the furnace A;

[0072] By setting a grate in the gasifier, the airflow of the gasifier supplied from the first gasifier inlet flows from the center to the outer layer, and the airflow of the gasifier supplied from the second gasifier inlet flows from the outer layer to the center. On the basis of the upward flow of the main airflow, the lateral flow of the airflow is increased, thereby strengthening the contact and mixing of the gasifier and the solid raw material, and improving the gas-solid reaction rate.

[0073] Example 6

[0074] like Figure 6 As shown, based on Example 5, the phenol water recovery system of the two-stage gasifier is provided, and the gas processing mechanism includes an electric tar precipitator (800), a gas intercooler (900) and a phenol water pool (1000) which are connected in sequence; the gas inlet (810) of the electric tar precipitator is connected to the upper gas outlet (140), the gas outlet (820) of the electric tar precipitator is connected to the gas inlet (910) of the gas intercooler, the cooling medium in the gas intercooler (900) is cold water, an upper gas outlet (920) is provided in the middle of one side of the gas intercooler, and a phenol water outlet (930) of the gas intercooler which is connected to the phenol water inlet (1010) of the phenol water pool is provided at the lower part; the phenol water recovery outlet (1020) is provided on the phenol water pool, which is connected to the phenol water inlet (630) of the phenol water superheater.

[0075] In this embodiment, an electric tar collector (800), a gas intercooler (900) and a phenol water pool (1000) are further provided for recycling and cooling the upper section coal gas. The upper section coal gas outlet (150) is connected to the coal gas inlet (810) of the electric tar collector to remove tar from the upper section coal gas. The upper section coal gas then enters the coal gas intercooler (900) through the connected coal gas outlet (820) of the electric tar collector and the coal gas inlet (910) of the coal gas intercooler, and is cooled by cooling water. The cooled upper section coal gas (after being cooled to the target temperature) is discharged through the upper section coal gas outlet (920) of the coal gas intercooler and sent to the downstream process section; the condensate in the coal gas intercooler (900) is discharged into the phenol water pool (1000) through the phenol water outlet (930) of the connected coal gas intercooler and the phenol water inlet (1010) of the phenol water pool; the phenol water precipitated in the phenol water pool flows into the phenol water superheater through the phenol water outlet (1020) of the phenol water pool and the phenol water inlet (630) of the phenol water superheater, thereby realizing the recovery of phenol water in the upper section coal gas.

[0076] The phenol water recovery method of the phenol water recovery system of the two-stage coal gasifier of the utility model comprises the following steps:

[0077] Step 1: Raw coal is added from the charging port (110) at the top of the two-stage gasifier and moves downward, and a gasifying agent is added from the first gasifying agent inlet (120) and the second gasifying agent inlet (170) at the bottom of the two-stage gasifier and flows upward. The raw material undergoes drying, pyrolysis, gasification and combustion reactions in succession. The temperature of the gasification and combustion reaction zone can reach 800-1100°C. Unreacted ash is discharged from the slag discharge port (130) at the bottom of the two-stage gasifier, and the generated gas is discharged from the upper gas outlet (140) and the lower gas outlet (150) respectively.

[0078] Step 2: According to the gas temperature of each lower gas outlet, one or more gas outlets with a gas outlet temperature greater than 700°C are selected to open the valve, ensuring that the temperature of the lower gas discharged from the two-stage gasifier is greater than 700°C; the lower gas flows into the cyclone separator through the lower gas outlet (150) and the gas inlet (210) of the cyclone separator to separate the fly ash particles, and the separated fly ash particles are discharged through the fly ash outlet (230) of the cyclone separator; the purified The lower section coal gas that does not contain fly ash solid particles enters the phenol water superheater (300) through the coal gas outlet (220) of the cyclone separator and the coal gas inlet (310) of the phenol water superheater. The lower section coal gas exchanges heat with the phenol water saturated steam in the phenol water superheater. The temperature of the lower section coal gas decreases, and the temperature of the phenol water saturated steam increases and turns into superheated steam. The phenol water superheated steam merges with the heated oxygen-containing gas and enters the coal gasifier through the first gasifying agent inlet (120) and the second gasifying agent inlet (170).

[0079] Step 3: The lower section of coal gas in the phenol water superheater (300) enters the phenol water steam generator (401) via the coal gas outlet (320) of the phenol water superheater and the coal gas inlet (4011) of the phenol water steam generator. The lower section of coal gas exchanges heat with the phenol water, and the temperature of the lower section of coal gas is further reduced. The phenol water absorbs heat and evaporates into phenol steam and saturated water vapor. Part of the phenol water absorbs heat and evaporates into phenol steam and saturated water vapor to form a steam-water mixture. The phenol water steam and saturated water vapor pass through the phenol water steam outlet (4013) of the phenol water steam generator and the phenol water steam inlet (4021) of the phenol water steam drum. Entering the phenol water steam drum, the steam-water mixture enters the phenol water steam drum, phenol water saturated steam is separated in the phenol water steam drum and enters the phenol water superheater through the phenol water steam outlet (4023) of the phenol water steam drum and the phenol water steam inlet (330) of the phenol water superheater, and the waste in the phenol water steam drum is discharged through the sewage outlet (4024) on the phenol water steam drum; at the same time, the liquid phenol water separated in the phenol water steam drum (402) returns to the phenol water steam generator through the phenol water outlet (4022) of the phenol water steam drum and the phenol water inlet (4014) of the phenol water steam generator to be vaporized;

[0080] Step 4: The lower section of coal gas in the phenol water steam generator (402) flows into the air preheater (500) through the coal gas outlet (4012) of the phenol water steam generator and the coal gas inlet (510) of the air preheater. The lower section of coal gas exchanges heat with the oxygen-containing gas in the air preheater (using a heat pipe for heat exchange, the lower section of coal gas passes through the heat pipe, the oxygen-containing gas is in the air cavity, and the heat of the lower section of coal gas is transferred to the oxygen-containing gas in the air cavity through the heat pipe). The temperature of the lower section of coal gas is further reduced, and the temperature of the oxygen-containing gas is increased. The oxygen-containing gas in the air preheater (500) can be air passing through the heat pipe. Oxygen-enriched air obtained after treatment by a pressure swing adsorption device; oxygen-containing gas is heated by an air preheater (500) and discharged through the oxygen-containing gas outlet (540) of the air preheater, and merges with the superheated phenol water vapor discharged from the phenol water vapor outlet (340) of the phenol water superheater, the phenol vapor is decomposed into small molecular gases such as CO and H2 at high temperature, the oxygen-containing gas is oxygen, air, a mixture of oxygen and CO2, etc., the phenol water superheated vapor is mixed with the oxygen-containing gas and enters the gasifier through the first gasifying agent inlet (120) and the second gasifying agent inlet (170);

[0081] Step 5: The lower section of coal gas in the air preheater (500) flows into the phenol water preheater (600) through the coal gas outlet (520) of the air preheater and the coal gas inlet (610) of the phenol water preheater. The lower section of coal gas exchanges heat with the phenol water, and the temperature of the lower section of coal gas is further reduced. The phenol water in the phenol water preheater (600) (including the recovered phenol water discharged from the phenol water recovery outlet (1020) and the additional phenol water) rises in temperature and then enters the phenol water steam generator (401) through the phenol water outlet (640) of the phenol water preheater and the phenol water inlet (4014) of the phenol water steam generator.

[0082] Step 6: The lower section of coal gas in the phenol water preheater (600) flows into the coal gas cooler (700) through the coal gas outlet (620) of the phenol water preheater, and the lower section of coal gas is cooled to the target temperature and then sent to the downstream process section.

[0083] The number of devices and processing scales described herein are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

[0084] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with this field, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. The phenol water recovery system of the two-stage gasifier is characterized by: include: A gasifier (100) is provided with a feed port (110) at the top and a first gasifying agent inlet (120) at the bottom for introducing oxygen-containing gas into the gasifier (100); an upper gas outlet (140), at least one lower gas outlet (150), and at least one second gasifying agent inlet (170) are provided on one side of the gasifier from top to bottom; the upper gas outlet is connected to a gas processing mechanism, and the gas processing mechanism is provided with a phenol water recovery outlet and an upper gas discharge outlet; A phenol water superheater (300) is provided with a phenol water superheater gas inlet (310) communicating with the lower gas outlet, a phenol water superheater gas outlet (320), a phenol water steam inlet (330) of the phenol water superheater, and a phenol water steam outlet (340) of the phenol water superheater communicating with the first gasifying agent inlet (120) and the second gasifying agent inlet (170); The phenol water boiler (400) is provided with a phenol water inlet (430) of the phenol water boiler connected to the phenol water recovery outlet, a coal gas outlet (420) of the phenol water boiler, a coal gas inlet (410) of the phenol water boiler connected to the coal gas outlet (320) of the phenol water superheater, and a phenol water steam outlet (440) of the phenol water boiler connected to the phenol water steam inlet (330) of the phenol water superheater.

2. The phenol water recovery system for a two-stage gasifier according to claim 1, wherein: The gas cooler (700) is provided with a gas inlet (710) of the gas cooler connected to the gas outlet (420) of the phenol water boiler, and a lower gas outlet (720).

3. The phenol water recovery system for a two-stage gasifier according to claim 2, wherein: It also includes a cyclone separator (200), which has a cyclone separator gas inlet (210) on one side of the upper portion thereof, which is connected to the lower section gas outlet (150), a cyclone separator gas outlet (220) on the top portion thereof, which is connected to the phenol water superheater gas inlet (310), and a fly ash discharge outlet (230) on the bottom portion thereof.

4. The phenol water recovery system for a two-stage gasifier according to claim 3, characterized in that: Also includes: An air preheater (500) is provided with an air preheater gas inlet (510) connected to the gas outlet (420) of the phenol water boiler, an air preheater gas outlet (520), an oxygen-containing gas inlet (530), and an oxygen-containing gas outlet (540) connected to the first gasifying agent inlet (120) and the second gasifying agent inlet (170); The phenol water preheater (600) is provided with a phenol water preheater gas inlet (610) connected to the gas outlet (520) of the air preheater, a phenol water preheater gas outlet (620) connected to the gas inlet (710) of the gas cooler, a phenol water inlet (630), and a phenol water outlet (640) of the phenol water preheater connected to the phenol water inlet (430) of the phenol water boiler.

5. The phenol water recovery system for a two-stage gasifier according to claim 4, characterized in that: The phenol water boiler comprises a phenol water steam generator (401) and a phenol water steam drum (402). The phenol water steam generator (401) is provided with a phenol water steam generator gas inlet (4011) connected to the gas outlet (320) of the phenol water superheater, a phenol water steam generator gas outlet (4012) connected to the gas inlet (510) of the air preheater, and a phenol water steam generator gas outlet (4021) connected to the phenol water steam drum. The phenol water steam drum (402) is provided with a phenol water steam outlet (4023) of the phenol water steam drum connected to the phenol water steam inlet (330) of the phenol water superheater, and a sewage outlet (4024); the phenol water recovery outlet is connected to the phenol water inlet (4014) of the phenol water steam generator.

6. The phenol water recovery system for a two-stage coal gasifier according to claim 1, characterized in that: The coal gasifier (100) is provided with a grate (160) located below the second gasifying agent inlet (170); the bottom of the grate (160) is connected to the first gasifying agent inlet (120); and the top of the grate (160) is provided with an air distribution port connected to the reaction furnace of the coal gasifier (100).

7. The phenol water recovery system for a two-stage coal gasifier according to claim 6, characterized in that: The grate includes a multi-layer structure stacked from bottom to top, the diameter of the multi-layer structure decreases from bottom to top, each layer of the structure is provided with an air distribution port, and the ventilation volume of the air distribution port on the multi-layer structure decreases from top to bottom; the ventilation volume per unit area of ​​the air distribution port on the topmost structure does not exceed 200% of the average ventilation volume per unit area, and the ventilation volume per unit area of ​​the air distribution port on the bottommost structure is not less than 30% of the average ventilation volume per unit area.

8. The phenol water recovery system for a two-stage gasifier according to claim 1, wherein: There are at least two lower gas outlets, and the multiple lower gas outlets are distributed at at least two different heights; each lower gas outlet is provided with a valve.

9. The phenol water recovery system for a two-stage coal gasifier according to claim 4, characterized in that: The air preheater (500) is a heat pipe heat exchanger.

10. The phenol water recovery system for a two-stage coal gasifier according to claim 5, characterized in that: The coal gas processing mechanism comprises an electric tar collector (800), a coal gas intercooler (900) and a phenol water pool (1000) which are connected in sequence; the coal gas inlet (810) of the electric tar collector is connected to the upper coal gas outlet (140), the coal gas outlet (820) of the electric tar collector is connected to the coal gas inlet (910) of the coal gas intercooler, the cooling medium in the coal gas intercooler (900) is cold water, an upper coal gas outlet (920) is provided in the middle of one side of the coal gas intercooler, and a phenol water outlet (930) of the coal gas intercooler which is connected to the phenol water inlet (1010) of the phenol water pool is provided at the lower part; the phenol water recovery outlet (1020) is provided on the phenol water pool and is connected to the phenol water inlet (4014) of the phenol water steam generator.

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