Treatment device for waste hydrochloric acid and waste phosphoric acid

Abstract

The utility model discloses a treatment device for waste hydrochloric acid and waste phosphoric acid. The treatment device comprises an alkaline material preparation tank, a neutralization reaction tank, a gas washing tower, an incinerator and deep treatment equipment. A feeding hole of the alkaline material preparation tank is connected with the water tank and the alkaline raw material tank; the top of the neutralization reaction tank is provided with a waste acid feed port and a headspace gas discharge port, and the neutralization reaction tank is provided with an alkaline material feed port, a middle lower part discharge port and a bottom discharge port; the waste acid feeding hole is connected with a waste acid storage tank; the alkaline material inlet is connected with an outlet of the alkaline material preparation tank; a gas inlet of the gas washing tower is connected with a headspace gas discharge outlet of the neutralization reaction tank; if hydrochloric acid is treated, a discharge port at the middle lower part of the neutralization reaction tank is connected with a feed port of deep treatment equipment; if phosphoric acid is treated, a discharge port at the middle lower part of the neutralization reaction tank is connected with a feed port of the incinerator; and a gas inlet of the incinerator is connected with a gas outlet of the gas washing tower through a fan. According to the utility model, the subsequent incineration amount can be reduced.

Description

Technical Field

[0001] This utility model relates to a device for treating waste hydrochloric acid and waste phosphoric acid. Background Technology

[0002] Hydrochloric acid and phosphoric acid are commonly used acids in industry. After use, the acid solution that has not reacted completely forms waste acid, which is a type of hazardous waste and requires professional disposal agencies to handle.

[0003] Currently, the main methods for disposing of waste hydrochloric acid include neutralization, solvent extraction, and distillation. Neutralization involves reacting waste hydrochloric acid with alkaline substances such as lime milk to produce harmless salt and water. Solvent extraction uses organic solvents to extract hydrogen chloride from waste hydrochloric acid for further recycling or treatment.

[0004] Common methods for disposing of waste phosphoric acid include precipitation, adsorption, and membrane separation. Precipitation involves adding a suitable precipitant to remove phosphate ions by forming a precipitate. Adsorption removes phosphoric acid by using adsorbents such as activated carbon. Membrane separation separates phosphoric acid from other impurities using the selective permeability of membranes.

[0005] Due to efficiency concerns, hazardous waste incineration companies often directly inject large quantities of waste acid into the incineration equipment for disposal, which can easily cause blockage of flue gas purification equipment, corrosion of refractory materials, and excessive emissions of flue gas and wastewater. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a device for treating waste hydrochloric acid and waste phosphoric acid, which can reduce the amount of subsequent incineration and reduce flue gas emissions.

[0007] The purpose of this utility model is achieved as follows: a treatment device for waste hydrochloric acid and waste phosphoric acid, comprising an alkaline material preparation tank, a neutralization reaction tank, a gas scrubbing tower, an incinerator, and advanced treatment equipment; wherein,

[0008] The feed port of the alkaline material preparation tank is connected to the water tank and the alkali raw material tank;

[0009] The neutralization reaction vessel is provided with a waste acid inlet and a headspace gas outlet at the top, an alkaline material inlet at the upper part, and a lower middle discharge outlet and a bottom discharge outlet corresponding to each other at the middle and lower parts and the bottom. The waste acid inlet is connected to a waste acid storage tank, and the alkaline material inlet is connected to the outlet of an alkaline material preparation tank.

[0010] The gas scrubbing tower’s inlet is connected to the headspace gas outlet of the neutralization reaction vessel;

[0011] If hydrochloric acid is being disposed of, the discharge port at the lower part of the neutralization reaction vessel is connected to the inlet of the deep treatment equipment;

[0012] If phosphoric acid is being disposed of, the discharge port at the lower part of the neutralization reaction vessel is connected to the feed port of the incinerator;

[0013] The inlet of the incinerator is connected to the outlet of the gas scrubbing tower via a blower.

[0014] The aforementioned waste hydrochloric acid and waste phosphoric acid treatment device includes an agitator installed in the alkaline material preparation tank; an agitator, pH meter, thermometer, and level gauge installed in the neutralization reaction tank; and a pH meter installed inside the gas scrubbing tower.

[0015] In the aforementioned waste hydrochloric acid and waste phosphoric acid treatment device, a bypass pipe is connected between the bottom discharge port of the neutralization reaction tank and the middle and lower discharge port; the bottom discharge port of the neutralization reaction tank is also connected to the feed port of the incinerator through a material transfer box.

[0016] The waste hydrochloric acid and waste phosphoric acid treatment device of this invention is characterized by: firstly, neutralizing the waste acid and alkaline materials in a neutralization reaction tank, and then sending the different forms of treatment products to different treatment equipment, including incineration or advanced treatment equipment, thus reducing the amount of subsequent incineration and reducing flue gas emissions. The acid mist generated during the neutralization reaction is washed by a gas scrubbing tower before being sent to the incinerator for combustion, avoiding clogging of the purification equipment. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the principle structure of the waste hydrochloric acid and waste phosphoric acid treatment device of this utility model. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Please see Figure 1 The waste hydrochloric acid and waste phosphoric acid treatment device of this utility model includes an alkaline material preparation tank 1, a neutralization reaction tank 2, a gas scrubbing tower 3, an incinerator 4, and a deep treatment device 6.

[0020] The feeding port of the alkaline material preparation tank 1 is connected to the water tank 11 and the alkali raw material tank 12. The alkaline material preparation tank 1 is equipped with a stirrer 10.

[0021] The neutralization reaction tank 2 is equipped with a waste acid inlet 21 and a headspace gas outlet 22 at the top. The upper part of the neutralization reaction tank 2 is equipped with an alkaline material inlet 23. The middle and lower parts and the bottom of the neutralization reaction tank 2 are equipped with a middle and lower discharge outlet 24 and a bottom discharge outlet 25 respectively. A bypass pipe 26 is connected between the middle and lower discharge outlet 24 and the bottom discharge outlet 25. The waste acid inlet 21 is connected to the waste acid storage tank 20 or an IBC (plastic ton container) containing waste acid. The alkaline material inlet 23 is connected to the outlet of the alkaline material preparation tank 1. The neutralization reaction tank 2 is equipped with a stirrer, pH meter, thermometer and level gauge.

[0022] The gas scrubbing tower 3 is connected to the headspace gas discharge port 22 of the neutralization reaction vessel 2; a pH meter is also installed inside the gas scrubbing tower.

[0023] If hydrochloric acid is being disposed of, the discharge port 24 at the lower part of the neutralization reaction tank 2 is connected to the inlet of the deep treatment equipment 6.

[0024] If phosphoric acid is to be disposed of, the discharge port 24 in the lower middle part of the neutralization reaction vessel 2 is connected to the feed port of the incinerator 4.

[0025] The air inlet of the incinerator 4 is connected to the exhaust port of the gas scrubbing tower 3 via the blower 40.

[0026] The working principle of the waste hydrochloric acid and waste phosphoric acid treatment device of this utility model is as follows: Lime and water are mixed in alkaline material preparation tank 1 to prepare lime slurry (alkaline material) required for neutralization reaction. After preparation, a batch of lime slurry is pumped to neutralization reaction tank 2. Waste hydrochloric acid or waste phosphoric acid in waste acid storage tank 20 is added to neutralization reaction tank 2 for neutralization reaction. The amount of waste hydrochloric acid or waste phosphoric acid added, reaction temperature and material level are controlled by pH meter, thermometer and liquid level gauge installed in neutralization reaction tank 2. During the neutralization reaction, due to the temperature rise, some acid mist will volatilize. It is sent to gas scrubbing tower 3 for washing through the headspace gas discharge port 22 of neutralization reaction tank 2 and pipeline equipped with fan (gas scrubbing tower 3 uses an alkaline solution prepared by industrial water and sodium hydroxide (NaOH) pipeline as absorbent, which is circulated by circulation pump). After being washed by gas scrubbing tower 3, the acid mist is sent to incinerator 4 for incineration.

[0027] The neutralization reaction produces a harmless liquid of salt and water, which is then allowed to cool and settle in the neutralization tank 2. Depending on the type of acid, it is sent to different treatment equipment. Specifically, the hydrochloric acid liquid after neutralization is discharged through the lower discharge port 24 of the neutralization tank 2 and sent to the deep treatment equipment 6 for desalination or evaporation and crystallization. The supernatant produced after neutralization of phosphoric acid is discharged through the lower discharge port 24 of the neutralization tank 2 and directly pumped to the incinerator 4 for incineration. The flue gas after incineration is emitted through the chimney 4A. The calcium phosphate precipitated at the bottom of the neutralization tank 2 is discharged through the bottom discharge port 25 and pumped into the material transfer box 5 by a mud pump. The material transfer box 5 transfers the precipitate to the solid waste pool, where it is mixed with the bulk waste in the solid waste pool and then sent to the incinerator 4 for incineration. The flue gas after incineration is emitted through the chimney 4A. The calcium phosphate that has settled at the bottom of the neutralization reaction tank 2 can also be directly pumped to the incinerator 4 for incineration through the bypass pipe 26 connected between the middle and lower discharge port 24 and the bottom discharge port 25; the bypass pipe 26 can also introduce the supernatant generated after the neutralization reaction of phosphoric acid into the material transfer box 5, and then send it to the incinerator 4 for incineration.

[0028] The above embodiments are for illustrative purposes only and are not intended to limit the present invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the scope of the present invention and should be defined by the claims.

Claims

1. A treatment apparatus for waste hydrochloric acid and waste phosphoric acid, comprising an alkaline material preparation tank, a neutralization reaction tank, a gas scrubbing tower, an incinerator, and advanced treatment equipment; characterized in that, The feed port of the alkaline material preparation tank is connected to the water tank and the alkali raw material tank; The neutralization reaction vessel is provided with a waste acid inlet and a headspace gas outlet at the top, an alkaline material inlet at the upper part, and a lower middle discharge outlet and a bottom discharge outlet corresponding to each other at the middle and lower parts and the bottom. The waste acid inlet is connected to a waste acid storage tank, and the alkaline material inlet is connected to the outlet of an alkaline material preparation tank. The gas scrubbing tower’s inlet is connected to the headspace gas outlet of the neutralization reaction vessel; If hydrochloric acid is being disposed of, the discharge port at the lower part of the neutralization reaction vessel is connected to the inlet of the deep treatment equipment; If phosphoric acid is being disposed of, the discharge port at the lower part of the neutralization reaction vessel is connected to the feed port of the incinerator; The inlet of the incinerator is connected to the outlet of the gas scrubbing tower via a blower.

2. The waste hydrochloric acid and waste phosphoric acid treatment apparatus according to claim 1, characterized in that, The alkaline material preparation tank is equipped with a stirrer; the neutralization reaction tank is equipped with a stirrer, pH meter, thermometer and level gauge; the gas scrubbing tower is also equipped with a pH meter.

3. The waste hydrochloric acid and waste phosphoric acid treatment apparatus according to claim 1, characterized in that, A bypass pipe is connected between the bottom discharge port of the neutralization reaction vessel and the middle and lower discharge port; the bottom discharge port of the neutralization reaction vessel is also connected to the feed port of the incinerator through a material transfer box.

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