A process and system for treating acrylonitrile tail gas by high temperature incineration

Abstract

The invention belongs to the environmental protection technology field of organic waste gas treatment and particularly relates to a process for pretreating and burning vinyl cyanide tail gas and a system for recycling waste heat of vinyl cyanide tail gas. The system comprises a gas-liquid separation tank, an incinerator, a combustion-supporting device, an SNCR (selective non-catalytic reduction) denitrification device, a waste heat boiler, a vinyl cyanide tail gas-exhaust gas continuous heat accumulation heat exchanger, a combustion-supporting air-exhaust gas continuous heat accumulation heat exchanger, an air blower and a chimney. According to a system for treating vinyl cyanide tail gas by a high temperature burning method, hazardous substances such as vinyl cyanide, hydrocyanic acid, carbon monoxide and non-methane hydrocarbon in the vinyl cyanide tail gas can realize high temperature oxidation decomposition, and the removal rate of the hazardous substances reaches beyond 99.99%. In comparison with the traditional high temperature burning method, 60-70% of fuel consumption can be directly saved; the treating method is high-efficiency and energy-saving, and the preheating temperature is lower 20-30 degrees centigrade than the decomposition temperature of organic ingredients in the tail gas, and thus the method is safe and steady and no coking is occurred.

Description

technical field

[0001] The invention belongs to the technical field of chemical organic waste gas treatment and environmental protection, and in particular relates to a system for pretreatment, incineration and waste heat recovery of acrylonitrile tail gas. Background technique

[0002] Acrylonitrile tail gas refers to the exhaust gas discharged from the top of the acrylonitrile absorption tower. This type of exhaust gas is characterized by large gas volume, low calorific value, fluctuating components and high toxicity. Since the emissions of acrylonitrile, hydrocyanic acid, carbon monoxide and non-methane hydrocarbons in the tail gas exceed the national environmental protection standards, direct high-point emissions that will cause harm to the environment have been banned.

[0003] The current treatment methods for this waste gas include: biological method, catalytic incineration method, high temperature incineration method.

[0004] The biological method has a slow reacti...

Examples

Embodiment 1

[0033] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0034]

[0035]

[0036] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0037] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0038] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

Embodiment 2

[0043] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0044]

[0045]

[0046] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0047] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0048] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

Embodiment 3

[0053] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0054]

[0055]

[0056] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0057] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0058] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

technical field

[0001] The invention belongs to the technical field of chemical organic waste gas treatment and environmental protection, and in particular relates to a system for pretreatment, incineration and waste heat recovery of acrylonitrile tail gas. Background technique

[0002] Acrylonitrile tail gas refers to the exhaust gas discharged from the top of the acrylonitrile absorption tower. This type of exhaust gas is characterized by large gas volume, low calorific value, fluctuating components and high toxicity. Since the emissions of acrylonitrile, hydrocyanic acid, carbon monoxide and non-methane hydrocarbons in the tail gas exceed the national environmental protection standards, direct high-point emissions that will cause harm to the environment have been banned.

[0003] The current treatment methods for this waste gas include: biological method, catalytic incineration method, high temperature incineration method.

[0004] The biological method has a slow reacti...

Examples

Embodiment 1

[0033] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0034]

[0035]

[0036] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0037] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0038] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

Embodiment 2

[0043] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0044]

[0045]

[0046] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0047] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0048] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

Embodiment 3

[0053] The composition and state parameters of the acrylonitrile tail gas to be treated are shown in the following table 1:

[0054]

[0055]

[0056] The steps of adopting the method of the present invention to process the above-mentioned acrylonitrile tail gas are as follows:

[0057] Step 1: The acrylonitrile tail gas enters the gas-liquid separation tank 1, and the condensate in the tail gas is separated and then transported to the acrylonitrile tail gas-flue gas heat exchanger 6 through a pipeline for preheating. The preheating temperature is 450-500°C ;

[0058] Step 2: The blower 8 provides combustion-supporting air, which is first sent to the combustion-supporting air-flue gas heat exchanger 7 for preheating. The preheating temperature is 200-500°C. The preheated air is sent to the incinerator 2 and the combustion supporter 3 respectively. The temperature in the chamber of the incinerator 2 is adjusted by adjusting the flow rate of the fuel in the burner 3, and ...

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