CN104689766A - Dry-burning preventing and long-service-life formaldehyde oxygenizer - Google Patents
Dry-burning preventing and long-service-life formaldehyde oxygenizer Download PDFInfo
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- CN104689766A CN104689766A CN201510128425.5A CN201510128425A CN104689766A CN 104689766 A CN104689766 A CN 104689766A CN 201510128425 A CN201510128425 A CN 201510128425A CN 104689766 A CN104689766 A CN 104689766A
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Abstract
The invention discloses a dry-burning preventing and long-service-life formaldehyde oxygenizer. The dry-burning preventing and long-service-life formaldehyde oxygenizer comprises an oxygenizer shell, heat exchanging pipes and a silver catalyst layer. The middle section of the oxygenizer shell is square, and the upper section and the lower section of the oxygenizer shell are an air inlet section and a discharging section respectively. The heat exchanging pipes are arranged inside the middle section of the oxygenizer shell so as to form a pipe shell type heat exchanger, the shell pass of the pipe shell type heat exchanger is used for circulation of reaction materials while the pipe pass is used for circulation of a heat source, and water inlets and water outlets of the heat exchanging pipe stretch out of the shell and are gathered through a water gathering pipe. A heat exchanging pipe in the oxygenizer is of a U-shaped structure, and a water inlet and a water outlet of the heat exchanging pipe are arranged on the same side of the oxygenizer shell. A bent end of at least the first layer heat exchanging pipe is of a half pipe closed structure, and a steam leading-out port is formed in the half pipe closed structure. The silver catalyst layer is arranged on the heat exchanging pipes. The oxygenizer is compact in structure, high in yield and capable of rapidly dissipating heat and exhausting gasified steam in the heat exchanging pipes to prevent dry burning of the heat exchanging pipes, and therefore the service life of the heat exchanging pipes is prolonged.
Description
Technical field
The invention belongs to chemical production technology and equipment technical field, relate generally to the oxidation of formaldehyde device for Formaldehyde Production.
Background technology
At present, silver-colored formaldehyde is produced and is mainly divided into following unit operations, methyl alcohol evaporation element, oxidation reaction unit, formaldehyde absorption unit, tail gas treating unit.And silver-colored formaldehyde produce in main oxidation reactor be nucleus equipment, the reasonability of oxidation of formaldehyde device project organization and the quality of workmanship directly affect formaldehyde end product quality, consumption of raw materials and oxidator service life.
At present, traditional structural formula ledge, catalyst case, quench zone form.Quench zone is actually a heat exchanger, and upper perforated plate directly lays copper mesh, catalyst is layered on copper mesh, shorten the distance of catalyst layer to quench zone like this, thus product yield is high, acidity can control at 100x10
-6below.But existing oxidation of formaldehyde device still exists following problem: oxidation of formaldehyde device operating temperature is 620 ~ 650 DEG C, because thermal stress can cause the drawing crack of tube sheet and heat exchanger tube; If exchanger tubes and tubesheets leaks, the medium of tube side and shell side can be caused to converge, cause production accident; If annual production production more than 120,000 tons, the volume of conventional oxidation device becomes large, becomes the equipment of transfiniting, cause transport constant while, the increase of span reduces equipment service life in high temperature environments; Formaldehyde medium walks tube side, and recirculated cooling water walks shell side, and technique is unreasonable, and heat transfer effect is bad; Tube side is walked formaldehyde medium and is run, and because whole tube sheet exists, resistance is large, and run uneconomical, energy consumption is large; There is the situation of dry combustion method in upper perforated plate, thus cause tube sheet hardening crack situation.
Summary of the invention
Goal of the invention: for above-mentioned Problems existing and defect, the invention provides a kind of dry-combustion-proof long-life oxidation of formaldehyde device, compact conformation, output are large and energy quick heat radiating discharges the steam gasified in heat exchanger tube, prevent heat exchanger tube dry combustion method, thus extend the life-span of heat exchanger tube.
Technical scheme: for achieving the above object, the present invention is by the following technical solutions: a kind of dry-combustion-proof long-life oxidation of formaldehyde device, comprise oxidator housing, heat exchanger tube and silver-colored Catalytic Layer, the stage casing of described heat exchanger shell is square, and epimere and hypomere are respectively air inlet section and discharging section; Described heat exchanger tube is located at the inside in oxidator housing stage casing thus forms shell-and-tube heat exchanger, the shell side of this shell-and-tube heat exchanger is for the reaction mass that circulates, and tube side is for circulating thermal source, and the water inlet of heat exchanger tube and delivery port all stretch out hull outside, and collect respectively by collector pipe; In described oxidator, heat exchanger tube is U-shaped structure, and heat exchanger tube water inlet and delivery port are located at the same side of oxidator housing; And the curved end semicanal enclosed construction of at least ground floor heat exchanger tube, and this semicanal enclosed construction is provided with steam outlet; Described silver-colored Catalytic Layer is located on heat exchanger tube.
As preferably, epimere and the hypomere of described oxidator housing are cylinder type, and oxidator housing epimere is provided with material inlet and gas distributor.
As preferably, the epimere of described oxidator shell is provided with cooling adjoining pipe.
As preferably, described heat exchanger tube is finned tube.
As preferably, also comprise the expansion joint of " L " font, the periphery of the upper end in described heat exchanger shell stage casing and one end of expansion joint affixed, the other end of expansion joint is then affixed with the epimere of heat exchanger shell thus the epimere of heat exchanger shell and stage casing are sealed, and the epimere of the upper end in heat exchanger shell stage casing and heat exchanger shell is movable contact.
As preferably, also comprise heat exchanger tube to support, this heat exchanger tube supports and is located between Multi-layer exchanging heat pipe, and described heat exchanger tube supports and comprises bottom support and intermediate support plate, described intermediate support plate is provided with multiple perforation corresponding with heat exchanger tube, and this perforation is provided with the reinforcing sleeve mated with heat exchanger tube external diameter; Under described bottom support is located at intermediate support plate.
As preferably, described heat exchanger tube is arranged with support set through the position of oxidator housing.
As preferably, described the superiors heat exchanger tube is provided with copper mesh brace rod, the upper flat of this copper mesh brace rod, and bottom is provided with the groove matched with heat exchanger tube external diameter.
Beneficial effect: compared with prior art, the present invention has the following advantages: (1) novel oxidized device structure adopts square, makes structure become compacter; (2) leak if solve exchanger tubes and tubesheets, the problem that the medium of tube side and shell side converges can be caused; (3) problem transport being only limited to output 120,000 tons/year is solved; (4) the bad problem of oxidator heat transfer effect is solved, under same heat exchange area, much fewer than common tube heat exchanger tube of finned tube, production capacity improves but equipment diminishes; (5) solve oxidator resistance large, run uneconomical, the problem that energy consumption is large; (6) service life of equipment can be increased to 10 years from 3 years.
Accompanying drawing explanation
Fig. 1 is the structural representation of oxidation of formaldehyde device of the present invention;
Fig. 2 is the structure enlarged diagram of A place expansion joint in Fig. 1;
Fig. 3 is the structure enlarged diagram of B place semicanal enclosed construction in Fig. 1;
Fig. 4 is the structure enlarged diagram that in Fig. 1, C place heat exchanger tube supports;
Fig. 5 is the structure enlarged diagram at D place in Fig. 1;
Fig. 6 is the structure enlarged diagram at E place in Fig. 1;
Fig. 7 is the structural representation of copper mesh brace rod of the present invention;
Fig. 8 is the structural representation of oxidation of formaldehyde device in prior art.
Wherein, ledge 1, stage casing 2, hypomere 3, heat exchanger tube 4, silver catalyst layer 5, manifold trunk 6, expansion joint 7, semicanal enclosed construction 8, steam outlet 9, intermediate support plate 10, bottom support 11, sleeve pipe 12, support set 13, copper mesh brace rod 14, material inlet 15, gas distributor 16, cooling adjoining pipe 17.
Detailed description of the invention
Below in conjunction with the drawings and specific embodiments, illustrate the present invention further, these embodiments should be understood only be not used in for illustration of the present invention and limit the scope of the invention, after having read the present invention, the amendment of those skilled in the art to the various equivalent form of value of the present invention has all fallen within the application's claims limited range.
As shown in Fig. 1 ~ 7, oxidation of formaldehyde device of the present invention, mainly comprises oxidator housing, expansion joint that heat exchanger tube, silver-colored Catalytic Layer, cross section are " L " font and heat exchanger tube supports, wherein:
Oxidator housing be divided into three sections, be respectively the collection of products section of the ledge of epimere, the reaction in stage casing and quench zone and hypomere, and the stage casing of oxidator housing is square, rib heat exchanging pipe is U-shaped structure, and the stage casing of oxidator housing is located in matrix form level, and water inlet and delivery port all to stretch out oxidator housing outer and be in the same side, then each water inlet and delivery port are collected respectively by manifold trunk.In addition, described heat exchanger tube supports and comprises bottom support and intermediate support plate, described intermediate support plate is provided with multiple perforation corresponding with heat exchanger tube, and this perforation is provided with the sleeve pipe mated with heat exchanger tube external diameter, and the position through heat exchanger tube on simultaneous oxidation device housing is also provided with cylindrical support cover.
Because the temperature of catalyst layer conversion zone is very high, 650 DEG C can be reached.Thermal expansion between the conversion zone of oxidator housing and quench zone is comparatively large, and therefore the weld in epimere and stage casing easily causes weld fatigue damage when expanding inconsistent, and then shortens service life.Preferably, the present invention arrange between the epimere ledge and upper end, stage casing of oxidator housing cross section for " L " expansion joint of font, the periphery of the upper end in oxidator housing stage casing and one end of expansion joint affixed, the other end of expansion joint is then affixed with the ledge of oxidator housing thus the epimere of oxidator housing and stage casing are sealed, and the epimere energy relative motion (as shown in Figure 2) of the upper end in oxidator housing stage casing and oxidator housing.Described expansion joint can be made up of stainless-steel sheet flanging, has some strength and suitable amount of deflection.More preferably good, only this expansion joint is set in the side in square oxidator stage casing, therefore dislocation dilation only occurs in side and moves, avoid the uncertainty of expansion direction.If when the thermal expansion of heat exchanger tube and cylindrical shell is inconsistent, cylinder board expands and is greater than the expansion of heat exchanger tube, and right side tube sheet (on the right side of oxidator housing) can move the thermal expansion compensating heat exchanger tube by left and right directions.
Inventor is in commissioning process, also find that upper row's heat exchanger tube adds easy damage most, learn through disassembling analysis: this is because the temperature of the reaction zone of oxidation of formaldehyde is greater than 620 DEG C ~ 650 DEG C, long-term work at such high temperatures, near silver catalyst layer the suitable evil of the working condition of row's rib heat exchanging pipe slightly, the operating mode of corresponding cylinder board be also suitable evil slightly.Under this operating mode, the quantity of steam that the finned tube of upper row produces instantaneously is very large, and finned tube inside may occur lack of water situation thus, thus causes the dry combustion method of finned tube, therefore must draw the steam produced fast in time.For this reason, the water inlet and delivery port of going up most the left side of the rib heat exchanging pipe of row are collected by manifold trunk by the present invention, but the U-shaped pipe bent position on right side then adopts half tubular construction, thus form the seal cavity of larger volume, and steam outlet is set on the top of seal cavity, fast steam is extracted out by the mode of negative pressure, the cooling water do not gasified then flows out along return duct from the delivery port of heat exchanger tube, thus avoid steam to be in the circulating resistance of the cooling water cannot discharging increase above pipe, or even the dry combustion method of heat exchanger tube, and then extend the service life of finned tube.
As shown in Figure 4, also comprise heat exchanger tube and support, described heat exchanger tube supports and comprises bottom support and intermediate support plate, and described intermediate support plate is provided with multiple perforation corresponding with heat exchanger tube, and this perforation is provided with the sleeve pipe mated with fin heat exchange pipe external diameter; Under described bottom support is located at intermediate support plate.As shown in Figure 7, be the copper mesh brace rod of the fixing band groove of the top erection of intermediate support plate.Because the copper mesh of silver catalyst layer will be laid on finned tube, but finned tube spacing is larger, be not enough to support whole copper mesh, if do not add support copper mesh can naturally droop, whole copper mesh is uneven, and catalyst is just difficult to be evenly distributed, thus affects whole reaction effect, copper mesh is laid on finned tube, effectively can guarantee the flatness of the whole plane of silver layer and shorten the time of catalytic oxidation to quench zone.Therefore, on certain length, add copper mesh gripper shoe according to the distance of finned tube and finned tube top can be made like this to be approximately a grid frame, lay copper mesh above, copper mesh is just very smooth.Further improvement, described heat exchanger tube is also arranged with support set through the position of oxidator housing.
Further improvement, in order to avoid excessive deformation and burning problem can not occur the stainless steel ledge of oxidator housing under 650 DEG C of high temperature long-term works, and stainless steel sensitization and crack damage, the present invention is provided with cooling adjoining pipe at the outer wall of ledge, reduce the temperature of this part, thus improve the service life of equipment.
When rib heat exchanging pipe is installed, the steel pipe of support set is first used in the perforation place welding that oxidator housing is corresponding, and vertically place intermediate support plate in stage casing simultaneously, then finned tube is inserted in the steel pipe of oxidator housing correspondence perforation, continue through intermediate support plate, after all finned tubes are all put on, be welded and fixed intermediate support plate, continue to push the oxidator housing of finned tube through opposite, and the built-up welding of gap place is sealed.Then on the superiors' finned tube, set up copper mesh brace rod, the upper flat of this copper mesh brace rod, bottom is provided with the groove matched with heat exchanger tube external diameter, then silver catalyst copper mesh layers is superposed successively and is laid on top.Preferably, on the right side of oxidator housing, the aperture of the perforation opposing left of (side namely residing for U heat exchange bending end) is larger, thus adjustment when facilitating heat exchanger tube to run through installation, the wall thickness of the support set of its same correspondence is larger thus mate with perforation.
In sum, the present invention mainly solves the following technique and manufacturing technology difficult point that in silver-colored formaldehyde device, oxidation of formaldehyde device exists:
(1) change the shell side of the cooling medium that circulates in prior art into circulation reaction mass, tube side then circulates the mode of cooling medium, greatly reduces the running resistance of oxidator, improves output economy, reduce energy consumption.
(2) adopt novel square oxidator structure, make more compact structure, output is larger, while convenient transport, is more conducive to the different thermal expansion of parts of controlled oxidization device and the direction of cold events, increases the service life.
(3) finned tube is designed to U-shaped bend pipe, and delivery port and water inlet all stretch out outside housing, thus completely avoid the problem of the mixing of tube side and the shell side material caused because heat exchanger tube or tube sheet occur to leak;
(4) half tubular-shaped structures is designed to the bend loss of the superiors' rib heat exchanging pipe, steam can be drawn fast, thus heat exchanger tube dry combustion method can be prevented; Simultaneous oxidation device housing design L-type expansion joint, provides expansion compensation, avoids that tube sheet expansion amplitude is inconsistent causes welding position to damage and the high-temperature fatigue damage of housing;
(5) also supported by the heat exchanger of band pipe box in addition, thus improve the intensity of heat exchanger tube, avoid the distortion causing heat exchanger tube because heat exchanger tube span is excessive.
Claims (8)
1. a dry-combustion-proof long-life oxidation of formaldehyde device, is characterized in that: comprise oxidator housing, heat exchanger tube and silver-colored Catalytic Layer, and the stage casing of described heat exchanger shell is square, and epimere and hypomere are respectively air inlet section and discharging section; Described heat exchanger tube is located at the inside in oxidator housing stage casing thus forms shell-and-tube heat exchanger, the shell side of this shell-and-tube heat exchanger is for the reaction mass that circulates, and tube side is for circulating thermal source, and the water inlet of heat exchanger tube and delivery port all stretch out hull outside, and collect respectively by collector pipe; In described oxidator, heat exchanger tube is U-shaped structure, and heat exchanger tube water inlet and delivery port are located at the same side of oxidator housing; And the curved end semicanal enclosed construction of at least ground floor heat exchanger tube, and this semicanal enclosed construction is provided with steam outlet; Described silver-colored Catalytic Layer is located on heat exchanger tube.
2. oxidation of formaldehyde device according to claim 1, is characterized in that: epimere and the hypomere of described oxidator housing are cylinder type, and oxidator housing epimere is provided with material inlet and gas distributor.
3. oxidation of formaldehyde device according to claim 1, is characterized in that: the epimere of described oxidator shell is provided with cooling adjoining pipe.
4. oxidation of formaldehyde device according to claim 1, is characterized in that: described heat exchanger tube is finned tube.
5. oxidation of formaldehyde device according to claim 1, it is characterized in that: the expansion joint also comprising " L " font, the periphery of the upper end in described heat exchanger shell stage casing and one end of expansion joint affixed, the other end of expansion joint is then affixed with the epimere of heat exchanger shell thus the epimere of heat exchanger shell and stage casing are sealed, and the epimere of the upper end in heat exchanger shell stage casing and heat exchanger shell is movable contact.
6. oxidation of formaldehyde device according to claim 1, it is characterized in that: also comprise heat exchanger tube and support, this heat exchanger tube supports and is located between Multi-layer exchanging heat pipe, described heat exchanger tube supports and comprises bottom support and intermediate support plate, described intermediate support plate is provided with multiple perforation corresponding with heat exchanger tube, and this perforation is provided with the reinforcing sleeve mated with heat exchanger tube external diameter; Under described bottom support is located at intermediate support plate.
7. oxidation of formaldehyde device according to claim 1, is characterized in that: described heat exchanger tube is arranged with support set through the position of oxidator housing.
8. oxidation of formaldehyde device according to claim 1, it is characterized in that: described the superiors heat exchanger tube is provided with copper mesh brace rod, the upper flat of this copper mesh brace rod, bottom is provided with the groove matched with heat exchanger tube external diameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510128425.5A CN104689766B (en) | 2015-03-24 | 2015-03-24 | A kind of dry-combustion-proof long-life oxidation of formaldehyde device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510128425.5A CN104689766B (en) | 2015-03-24 | 2015-03-24 | A kind of dry-combustion-proof long-life oxidation of formaldehyde device |
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| CN104689766A true CN104689766A (en) | 2015-06-10 |
| CN104689766B CN104689766B (en) | 2017-10-31 |
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| JP2010069355A (en) * | 2008-09-16 | 2010-04-02 | Mitsubishi Chemicals Corp | Plate type reactor and method for manufacturing reaction product using the same |
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| CN104190327A (en) * | 2014-08-27 | 2014-12-10 | 江苏凯茂石化科技有限公司 | Novel formaldehyde oxidation reaction device |
| CN104248939A (en) * | 2014-09-16 | 2014-12-31 | 江苏凯茂石化科技有限公司 | Methanol oxidizer in silver catalyst process formaldehyde device |
| CN204115529U (en) * | 2014-08-20 | 2015-01-21 | 冯喜旺 | A kind of new steel structure tubular heat exchanger |
| CN204638156U (en) * | 2015-03-24 | 2015-09-16 | 江苏凯茂石化科技有限公司 | A kind of dry-combustion-proof long-life oxidation of formaldehyde device |
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2015
- 2015-03-24 CN CN201510128425.5A patent/CN104689766B/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010069355A (en) * | 2008-09-16 | 2010-04-02 | Mitsubishi Chemicals Corp | Plate type reactor and method for manufacturing reaction product using the same |
| CN201978730U (en) * | 2011-01-27 | 2011-09-21 | 淮南市石油化工机械设备有限公司 | Impact-resistant formaldehyde oxidization reactor |
| CN103785334A (en) * | 2012-11-02 | 2014-05-14 | 河北化大科技有限公司 | Large fluidized bed reactor |
| CN204115529U (en) * | 2014-08-20 | 2015-01-21 | 冯喜旺 | A kind of new steel structure tubular heat exchanger |
| CN104190327A (en) * | 2014-08-27 | 2014-12-10 | 江苏凯茂石化科技有限公司 | Novel formaldehyde oxidation reaction device |
| CN104248939A (en) * | 2014-09-16 | 2014-12-31 | 江苏凯茂石化科技有限公司 | Methanol oxidizer in silver catalyst process formaldehyde device |
| CN204638156U (en) * | 2015-03-24 | 2015-09-16 | 江苏凯茂石化科技有限公司 | A kind of dry-combustion-proof long-life oxidation of formaldehyde device |
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Granted publication date: 20171031 Termination date: 20180324 |