Disclosure of Invention
Aiming at the problems in the adsorption treatment process of high-humidity industrial waste gas in the prior art, the invention aims to provide a high-humidity industrial waste gas purification device and a high-humidity industrial waste gas purification method.
In order to achieve the purpose, the invention adopts the following technical scheme:
in one aspect, the invention provides a high-humidity industrial waste gas purification device, which comprises a dehydration adsorption unit, a waste gas adsorption unit and an adsorbent regeneration unit, wherein an outlet of the dehydration adsorption unit is connected with an inlet of the waste gas adsorption unit, the dehydration adsorption unit comprises at least three dehydration adsorption towers connected in parallel, and the waste gas adsorption unit comprises at least two waste gas adsorption towers connected in parallel;
the adsorbent regeneration unit includes temperature regulator, regeneration pipeline and cooling line, the cooling line is through dehydration adsorption unit and temperature regulator's entry linkage, temperature regulator's outlet pipeline includes two regeneration pipelines, and one links to each other with dehydration adsorption unit, and another links to each other with waste gas adsorption unit.
According to the device, the dehydration adsorption unit and the waste gas adsorption unit are independently arranged, so that moisture and organic components in the industrial waste gas are respectively removed, and the problems that the waste gas removal rate is reduced and the service life of the adsorbent is short due to competitive adsorption of water molecules on the adsorbent and waste gas molecules during common adsorption are solved; the adsorption towers are arranged in parallel, so that different adsorption towers can be respectively in adsorption, regeneration and cooling processes, continuous treatment of industrial waste gas is ensured, and the treatment efficiency of the waste gas is improved; the regeneration unit can rapidly realize the regeneration of the adsorbent, and the appropriate regeneration conditions can be selected according to the different compositions of the waste gas, so that the application range is wide.
The following technical solutions are preferred technical solutions of the present invention, but not limited to the technical solutions provided by the present invention, and technical objects and advantageous effects of the present invention can be better achieved and achieved by the following technical solutions.
In a preferred embodiment of the present invention, the dehydration adsorption tower in the dehydration adsorption unit comprises at least one tower for adsorption, one tower for regeneration and one tower for cooling.
Preferably, the number of the waste gas adsorption towers in the waste gas adsorption unit is 2-4, such as 2, 3 or 4, and the selection of the specific number is related to the treatment capacity of the waste gas, the size of the waste gas adsorption tower and the packing rate of the adsorbent.
Preferably, the off-gas adsorption columns are regenerated sequentially.
Generally speaking, for industrial waste gas with large air volume and low concentration, the time required for the saturation of the adsorbent in the waste gas adsorption tower is longer, so that in a cycle process, the adsorption tower is in an adsorption process for most of time, when regeneration is needed, different adsorption towers are respectively carried out, the adsorption tower is in an adsorption state at any moment, and the continuous treatment of the waste gas is ensured.
Preferably, the dehydration adsorption tower and the off-gas adsorption tower are filled with adsorbents.
In a preferred embodiment of the present invention, the high humidity industrial waste gas is connected to an inlet of a dehydration adsorption tower.
Preferably, an outlet of the waste gas adsorption unit is connected with an adsorption fan.
Preferably, an adsorption fan is arranged at the outlet of each waste gas adsorption tower.
According to the invention, the flow velocity of the industrial waste gas can be effectively regulated by arranging the adsorption fan, so that the treatment rate of the industrial waste gas can be regulated, and the industrial waste gas can be timely regulated according to the concentration of the waste gas.
Preferably, the outlet and the inlet of the dehydration adsorption tower and the outlet and the inlet of the waste gas adsorption tower are respectively provided with a valve.
As the preferable technical scheme of the invention, cooling gas is introduced into the cooling pipeline, and the cooling gas sequentially passes through the dehydration adsorption tower and the temperature regulator to be used as regeneration gas.
In the invention, in order to improve the utilization efficiency of gas and heat, the temperature of the gas passing through the cooling pipeline is increased, and the gas is adjusted to be suitable for the regeneration of the adsorbent.
Preferably, a three-way valve is arranged at the branch of the regeneration pipeline.
Preferably, a desorption fan is arranged at an outlet of the regeneration pipeline.
Preferably, a first desorption fan is arranged on the regeneration pipeline passing through the dehydration adsorption tower, and a second desorption fan is arranged on the regeneration pipeline passing through the waste gas adsorption tower.
In the invention, because the adsorption towers of the dehydration adsorption unit and the waste gas adsorption unit need to be regenerated, a three-way valve is arranged on a regeneration pipeline passing through the temperature regulator, and the regeneration pipeline is divided into two branches and is respectively used for regenerating adsorbents in the dehydration adsorption tower and the waste gas adsorption tower.
Preferably, the outlet of the second desorption fan is further connected with a subsequent treatment device.
In the invention, after the exhaust gas molecules are adsorbed, the exhaust gas molecules are desorbed in the regeneration process to obtain concentrated exhaust gas, and then the concentrated exhaust gas is subjected to subsequent exhaust gas treatment, such as combustion, catalytic oxidation and the like.
Preferably, valves are arranged at the positions of the cooling pipeline and the regeneration pipeline for entering and exiting the dehydration adsorption tower and the waste gas adsorption tower.
In another aspect, the present invention provides a method for purifying high humidity industrial waste gas using the above apparatus, the method comprising the steps of:
(1) the high-humidity industrial waste gas enters a dehydration adsorption tower for dehydration adsorption, then enters a waste gas adsorption tower for waste gas adsorption, and the obtained purified gas is discharged;
(2) after the dehydration adsorption tower in the step (1) is saturated in adsorption, regenerating adsorbent by using regenerated gas passing through a cooling pipeline and a temperature regulator, cooling the dehydration adsorption tower by using cooling gas after regeneration is finished, and discharging the cooling gas to enter the temperature regulator;
(3) and (2) after the waste gas adsorption tower in the step (1) is saturated in adsorption, regenerating the adsorbent by using regenerated gas passing through a cooling pipeline and a temperature regulator, and carrying desorbed enriched waste gas with the regenerated gas for subsequent treatment.
As a preferred technical scheme of the invention, the component of the high-humidity industrial waste gas in the step (1) comprises H2O and off-gas components.
Preferably, the volume fraction of water vapor in the high humidity industrial waste gas is 3% to 5%, for example 3%, 3.5%, 4%, 4.5%, or 5%, etc., but is not limited to the recited values, and other values not recited in the range of values are also applicable.
Preferably, the waste gas components in the high-humidity industrial waste gas comprise VOCs and H2S or HCN, or a combination of at least two of S or HCN, said combination comprising VOCs and H2Combination of S, H2Combination of S and HCN, VOCs, H2S and HCN, and the like.
As a preferable technical scheme of the invention, the adsorbent filled in the dehydration adsorption tower in the step (1) comprises a 3A type molecular sieve and/or a 4A type molecular sieve, and effective desorption of water vapor can be realized.
Preferably, at least three dehydration adsorption towers in step (1) are arranged in parallel, for example, three, four, five or six dehydration adsorption towers are arranged in parallel.
Preferably, the temperature of the dehydration adsorption in step (1) is 20 to 50 ℃, for example, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 45 ℃ or 50 ℃, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the adsorption time of each dehydration adsorption column in step (1) is 2 to 6 hours, such as 2 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours or 6 hours, but not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the adsorbent packed in the off-gas adsorption column of step (1) comprises any one of or a combination of at least two of an X-type molecular sieve, a Y-type molecular sieve, an a-type molecular sieve or a ZSM-type molecular sieve, and typical but non-limiting examples of the combination include: the combination of the X-type molecular sieve and the Y-type molecular sieve, the combination of the A-type molecular sieve and the ZSM-type molecular sieve, the combination of the X-type molecular sieve, the Y-type molecular sieve and the A-type molecular sieve, the combination of the X-type molecular sieve, the Y-type molecular sieve, the A-type molecular sieve and the ZSM-type molecular sieve and the like.
In the invention, the A-type molecular sieve comprises a 3A-type molecular sieve, a 4A-type molecular sieve and the like, and when industrial waste gas contains H2S, HCN, etc., molecular sieves of this type can be packed for adsorption.
Preferably, at least two, for example two, three or four, etc., waste gas adsorption columns are arranged in parallel in the step (1).
Preferably, the temperature for adsorbing the exhaust gas in the step (1) is 20 to 50 ℃, for example, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 45 ℃ or 50 ℃, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the adsorption time of each off-gas adsorption column in step (1) is 5 to 30 days, for example, 5 days, 10 days, 15 days, 20 days, 25 days, or 30 days, etc., but is not limited to the recited values, and other values not recited in the range of the values are also applicable.
As a preferred technical scheme of the invention, the regeneration gas in the step (2) comprises nitrogen and/or air.
In the invention, the regeneration gas can be selected according to the difference between the adsorption tower and the treatment atmosphere, the dehydration adsorption tower can select air as the regeneration gas, and the waste gas adsorption tower treats H2S, HCN, nitrogen can be used as the regeneration gas, and air can be used as the regeneration gas for treating the VOCs atmosphere.
Preferably, the temperature for regenerating the adsorbent in step (2) is 100 to 150 ℃, for example, 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃ or 150 ℃, but not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the adsorbent in step (2) is regenerated for 2-6 h, such as 2h, 3h, 3.5h, 4h, 4.5h, 5h or 6h, but not limited to the recited values, and other values not recited in the range of the recited values are also applicable.
Preferably, the cooling gas of step (2) is the same as the regeneration gas.
In the invention, the dehydration adsorption tower is cooled by gas purging and then used as the regeneration gas, so that the residual heat of the adsorption tower is fully utilized, and the consumption of the heat required by the temperature rise of the regeneration gas is reduced.
Preferably, the cooling time in step (2) is 2-6 h, such as 2h, 3h, 3.5h, 4h, 4.5h, 5h or 6h, but not limited to the recited values, and other values not recited in the range of the values are also applicable.
As a preferred technical scheme of the invention, the regeneration gas in the step (3) comprises nitrogen and/or air.
Preferably, the temperature for regenerating the adsorbent in step (3) is 150 to 200 ℃, for example 150 ℃, 160 ℃, 170 ℃, 180 ℃, 190 ℃ or 200 ℃, but not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the adsorbent in step (3) is regenerated for 8-24 h, such as 8h, 10h, 12h, 15h, 18h, 20h or 24h, but not limited to the recited values, and other values in the range are also applicable.
Preferably, after the adsorbent in the step (3) is regenerated, the off-gas adsorption tower is cooled.
In the invention, because the adsorption time in the waste gas adsorption tower is much longer than the regeneration time, when one waste gas adsorption tower is used for adsorption, the other waste gas adsorption tower can finish the regeneration and cooling processes in turn, and the regenerated gas carries the enriched and concentrated waste gas for subsequent treatment to realize the purification of waste gas components.
As a preferred technical scheme of the invention, the method comprises the following steps:
(1) the method comprises the steps that high-humidity industrial waste gas firstly enters a dehydration adsorption tower for dehydration adsorption, the volume fraction of water vapor in the high-humidity industrial waste gas is 3% -5%, the dehydration adsorption temperature is 20-50 ℃, the adsorption time of each dehydration adsorption tower is 2-6 hours, then the high-humidity industrial waste gas enters a waste gas adsorption tower for waste gas adsorption, the waste gas adsorption temperature is 20-50 ℃, the adsorption time of each waste gas adsorption tower is 5-30 days, and the obtained purified gas is discharged;
(2) after the dehydration adsorption tower in the step (1) is saturated in adsorption, regenerating the adsorbent by using regenerated gas passing through a cooling pipeline and a temperature regulator, wherein the regeneration temperature is 100-150 ℃, the regeneration time is 2-6 h, cooling the dehydration adsorption tower by using cooling gas after the regeneration is finished, the cooling time is 2-6 h, and the cooling gas is discharged and enters the temperature regulator;
(3) and (2) after the waste gas adsorption tower is saturated in adsorption, regenerating the adsorbent by using regenerated gas passing through a cooling pipeline and a temperature regulator, wherein the regeneration temperature of the adsorbent is 150-200 ℃, the regeneration time is 8-24 h, the waste gas adsorption tower is cooled after the adsorbent is regenerated, and the regenerated gas carries the desorbed enriched waste gas for subsequent treatment.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, through the arrangement of two stages of adsorption units of dehydration adsorption and waste gas adsorption, moisture and waste gas components in the industrial waste gas can be respectively adsorbed and removed, so that the influence of moisture on the adsorption performance of the waste gas components is avoided, and meanwhile, the operation conditions of the adsorption tower can be respectively regulated and controlled, so that high-frequency adsorption regeneration of high-humidity water vapor and long-time concentration and enrichment of low-concentration waste gas are realized;
(2) the waste gas adsorption unit is independent of the dehydration adsorption unit, can flexibly adjust adsorption and regeneration conditions and the types of adsorbents according to waste gas components, realizes long-time stable adsorption of industrial waste gas, is simple to operate, saves the using amount of the adsorbents, and reduces the operation cost;
(3) the regeneration gas in the adsorbent regeneration unit is derived from the cooling gas of the dehydration adsorption tower, so that the heat in the regenerated adsorption tower is fully utilized, the energy consumption is reduced, and the economic benefit is improved.