CN203862227U - Cooling coil component - Google Patents

Abstract

The utility model relates to a cooling coil component. Cooling coils applied to a commercial oxidation reactor or an ammoxidation reactor can be used for limiting independent pipelines of the cooling coils for closer packaging by providing the transversal arrangement instead of the linear arrangement.

Description

Cooling coil assembly

Technical field

The utility model relates to cooling coil assembly.

Background technology

Various technique and system for the manufacture of acrylonitrile and methacrylonitrile are known.Common process is usually directed to recovery and the purification of the hydrocarbon acrylonitrile/methacrylonitrile that directly reaction produces in the situation that catalyst exists of the set by selecting free propane, propylene or isobutene, ammonia and oxygen formation.For example, in the business of acrylonitrile is manufactured, propylene, ammonia and oxygen react according to following reaction scheme one:

CH ₂=CH-CH ₃?+?NH ₃?+?3/2?O ₂?→?CH ₂=CH-CN?+?3?H ₂O

This process that is commonly referred to ammoxidation for example, is carried out with gas phase in the case of existing applicable fluid bed ammoxidation catalyst at the temperature (, 350 DEG C to 480 DEG C) raising.

Fig. 1 shows the typical acrylonitrile reactor for carrying out this process.As shown here, reactor 10 comprises shell of reactor 12, air grid 14, supplies with sprinkler 16, cooling coil 18 and cyclone separator 20.At normal operation period, process air is filled with in reactor 10 through air intake 22, and the mixture of propylene and ammonia is filled with in reactor 10 through supplying with sprinkler 16 simultaneously.Both flow velocitys are high enough to make ammoxidation catalyst bed 24 fluidisations in inside reactor, and propylene and the ammonia catalytic ammoxidation to acrylonitrile occurs at this place.

The product gas being produced by reaction leaves reactor 10 through reactor effluent outlet 26.Before doing like this, they are through cyclone separator 20, cyclone separator 20 remove that these gases may carry for getting back to any ammoxidation catalyst of catalyst bed 24 through dipping tube 25.Ammoxidation is highly heating normally, and therefore therefore cooling coil assembly 18, for extracting excessive heat, and remains on reaction temperature suitable level.

In this regard, Fig. 2 schematically shows the design for the conventional cooling coil assembly 18 of this object.Fig. 2 is the localized axial cross-sectional view of reactor 10, it shows one group of cooling coil in the cooling coil assembly of reactor 10, and this group cooling coil is made up of three independent cooling coils (cooling coil 42, cooling coil 44 and cooling coil 46).Cooling coil 42 comprise entrance 48 for receiving cooling water and for heated and be partly transformed into steam after discharge the outlet 50 of this cooling water.Equally, cooling coil 44 comprises entrance 52 and outlet 54, and cooling coil 46 comprises entrance 56 and outlet 58.As shown in Figure 2, cooling coil 42, each in 44 and 46 limits by a series of vertically cooling coil circuits 57 of orientation, and each circuit forms by a pair of microscler interconnection cooling duct 60, and this cooling duct 60 is connected to each other and is gone up by lower U-bend folding accessory 62 at its bottom place.Continuous cooling coil circuit 57 also its top place by U-bend folding accessory 63 be connected to each other and go up, to form the continuous-flow path from the entrance of each corresponding cooling coil to outlet.

Fig. 3 is the top view of the cooling coil assembly 18 shown in Fig. 2.As by from recognizing Fig. 2 and Fig. 3, cooling coil 42,44 and 46 forms one group of cooling coil, and it is coplanar, that is, each is arranged in common vertical plane.As further shown in Figure 3, cooling coil assembly 18 forms by organizing these cooling coils more, and wherein each group of these cooling coils is all arranged to parallel to each other and (alternatively) substantially and opens with equi-spaced apart each other.In addition, as can be further seen in Fig. 3, although the many cooling coil groups in this cooling coil assembly comprise three different cooling coils, other cooling coil group comprises two or four cooling coil, and two cooling coil groups comprise an only cooling coil.

Fig. 4 is the amplification top view intercepting on the line 4-4 of Fig. 2, shows the more details of the ad hoc structure of the cooling coil assembly 18 of Fig. 2 and Fig. 3.Particularly, Fig. 4 is the schematic diagram that the upper U-bend folding accessory 63 of cooling coil is only shown.

As shown in Figure 4, cooling coil 61 comprises entrance 35, entrance 35 is connected to the supply line 64 on the top of the first cooling coil circuit (not shown) of cooling coil 61, and for by the continuous coil pipe connection of cooling coil to a series of upper U-bend folding accessory 63 of going up each other.Also as shown in the drawing, all these elements (, all upper U-bend folding accessories 63 and supply line 64) are all coplanar, that is, and and their all being all positioned on identical common vertical plane D.In addition, from Fig. 2 and Fig. 3, by what further recognize be, all the other elements (, forming the cooling duct 60 and the lower U-bend folding accessory 62 being associated of the vertically orientation of each cooling coil circuit 57) in this cooling coil are also arranged in this common vertical plane.Shown in specific embodiment in, on each, U-bend folding accessory 63 is supported from below by backbar 70, backbar 70 is received in the inner curve being limited by each U-shaped accessory.Therefore, comprise all its member parts (, upper U-bend folding accessory 63, directed conduit 60 and lower U-shaped bending part 62 vertically) and the total weight of each cooling coil of the entire contents (, the cooling water of circulation) of cooling coil supported by its corresponding backbar 70.

As further shown in Figure 4, applicable aisle or passage 74 be arranged in certain altitude place between a cooling coil, this height, near upper U-bend folding accessory 63 places or its, is easy to approach to provide, and the making regular check on and/or any attendant that REPSH repair shop needs of supporting cooling coil.

Fig. 5 is another schematic diagram, and it shows the different cooling coils of how controlling in cooling coil assembly 18.In this regard, be to make cooling coil " in turn " in the convention of the run duration of conventional acrylonitrile reactor 10, that is, regularly close independently and continuously and then restart each cooling coil.Most of business ammoxidation catalysts make molybdenum refining, and molybdenum is generally deposited on the outer surface of cooling coil within a certain period of time as incrustation.Because this molybdenum incrustation adversely affects the performance of cooling coil, be often to remove this molybdenum incrustation to keep cooling coil suitably to act on therefore required.Generally speaking, this completes by regularly closing and then restarting each cooling coil, and this is because this closes/restart program owing to closing and then restarting that to cause the wide temperature fluctuation of cooling coil experience to cause not be inapparent mechanical shock to cooling coil.This mechanical shock is in most of the cases enough to remove and may be deposited on lip-deep at least some the molybdenum incrustation of cooling coil, and has recovered in the case at least some thermal heat transfer capability of this coil pipe.Stable operation in this time period that has caused extending.

For by extremely independently cooling coil of chilled(cooling) water supply (CWS), generally use the structure shown in Fig. 5.As shown there, the entrance 35 of cooling coil 61 is communicated with process water inlet header 80 fluids, and the height of process water inlet header 80 is positioned to conventionally lower than upper U-bend folding accessory 63.Equally, the outlet 65 of cooling coil 61 is communicated with process water outlet header 62 fluids, and the height of process water outlet header 62 is positioned to conventionally higher than upper U-bend folding accessory 63.Generally speaking, process water inlet header 80 and outlet header 82 adopt the larger directed conduit form in continuous horizontal ground of Perfect Ring around reactor 10.Regularly close independently and restart each cooling coil and generally complete by the corresponding cut-off valve 84 being associated with the entrance 35 of this cooling coil, in great majority design, this cut-off valve 84 is simple switch valve, contrary with the control valve that can accurately control rate of flow of fluid.

Be also noted that, cut-off valve 84 is at least one valve in the cooling coil 61 between process water inlet header 80 and process water outlet header 82.That is to say, cooling coil 61 is configured to without any additional valve or other flow control apparatus, does not particularly export 65 flow control valves that are associated with cooling coil.This is because this type of additional valve needn't be realized the operation and control of the expectation of cooling coil in the manner described above.In addition, eliminate outlet flow control valve and also eliminated the needs to safety relief valve, use else if this outlet flow control valve, just will need safety relief valve (, by the PSV on each independent coil pipe of needs).

On whole reactor as a whole and acrylonitrile reactor to be remained in or approached its optimal reaction temperature from Yi Ge district in reactor to another district be important for good reactor performance.In addition, the rate limit step of the heap(ed) capacity that the normally definite acrylonitrile reactor of speed that can extract from reactor due to heat can move, therefore the design of good cooling coil is also important.In addition, poor cooling coil design and/or operation can cause excessive cooling coil corrosion, and this can need very expensive too early repairing.

Therefore, constantly need the improvement of the design and running of the cooling coil of business acrylonitrile reactor, not only improve reactor performance, and reduce the erosion of conduit, thereby reduce downtime and repair cost.

Utility model content

According to the utility model, to having carried out a series of improvement for typical oxidation reactor or ammonia oxidation reactor as the design and running of the cooling coil assembly of business acrylonitrile reactor.As a result, not only improve reactor performance, but also extended the service life of cooling coil assembly.

Therefore, in one embodiment, it is a kind of for removing the cooling coil assembly of the excessive heat being generated by oxidation reactor or ammonia oxidation reactor that the utility model provides, this cooling coil assembly comprises multiple cooling coils, each cooling coil includes multiple cooling coil circuits, it is fluidly connected in series to each other and goes up, to limit the cooling water path with cooling water inlet and coolant outlet, each cooling coil circuit limits vertically directed cooling coil track plan, wherein each cooling coil extends along the main cooling coil plane of corresponding vertically orientation towards the periphery of reactor in reactor, and further wherein, at least some cooling coil circuits at least one cooling coil are arranged such that the main cooling coil flat transverse of its cooling coil track plan and this cooling coil.

In addition, in a second embodiment, it is a kind of for removing the cooling coil assembly of the excessive heat being generated by oxidation reactor or ammonia oxidation reactor that the utility model provides, cooling coil assembly comprises single or multiple cooling coils, each cooling coil is all defined for the flow of cooling water path of carrying through the cooling water at this place, cooling water inlet and coolant outlet, each cooling coil also comprises the condensate water cutoff valve being associated with its cooling water inlet, each cooling coil is not also for controlling the valve through the cooling water flow of its coolant outlet, wherein the length of at least some flow of cooling water paths differs from one another.In this regard, the cooling coil of some is selected to provides about 15% or the average percent of the cooling water that is transformed into steam still less.

In addition, in the 3rd embodiment, it is a kind of for removing by having the oxidation reactor of wall or the cooling coil assembly of the excessive heat that ammonia oxidation reactor generates that the utility model provides, this cooling coil assembly comprises single or multiple cooling coils, each cooling coil includes multiple cooling coil circuits, it is fluidly connected in series to each other and goes up, so that restriction cooling water path, this cooling water path has through the cooling water inlet of the wall of reactor and coolant outlet, wherein cooling water inlet comprises the cooling coil inlet fitting on the wall that is attached to rigidly reactor, and thermal sleeve in the accessory of cooling water inlet, wherein the external diameter of thermal sleeve is less than the internal diameter of cooling coil inlet fitting, to limit heat space therebetween.

In another embodiment, it is a kind of for removing the cooling coil assembly of the excessive heat being generated by oxidation reactor or ammonia oxidation reactor that the utility model provides, this cooling coil assembly comprises multiple cooling coils, each cooling coil includes a series of cooling coil circuits, this circuit comprises the first circuit of serial beginning and the last circuit in serial end, multiple cooling coil circuits are fluidly connected to each other to be gone up, to limit the cooling water path with cooling water inlet and coolant outlet, cooling coil assembly also comprises the cooling coil inlet header being communicated with the first circuit fluid of each cooling coil and the coolant outlet collector being communicated with the last circuit fluid of each cooling coil, each cooling coil also comprises the coolant outlet conduit that the last circuit of this cooling coil is connected with coolant outlet collector, wherein the height of cooling coil outlet header is lower than the height of the cooling coil delivery channel of each cooling coil.

Preferably, the cooling coil in cooling coil assembly comprises at least three different lengths.

Preferably, cooling coil is made by the conduit with identical diameter, wherein some in cooling coil are shorter than other in cooling coil, and those cooling coils wherein, with shorter length comprise that at their flow passage limited part is for controlling the percentage of the cooling water that is transformed into steam.

Brief description of the drawings

The utility model can be by more easily understanding with reference to the following drawings, in the accompanying drawings:

Fig. 1 shows for carrying out propylene and the ammonia conventional business acrylonitrile reactor to the ammoxidation of acrylonitrile;

Fig. 2 illustrates for the structure of the conventional cooling coil design of the conventional business acrylonitrile reactor of Fig. 1 and the schematic diagram of operation;

Fig. 3 is the top view of the conventional cooling coil design of Fig. 2;

Fig. 4 is the top view that is similar to Fig. 3 that the more details of the conventional cooling coil design of Fig. 2 are shown;

Fig. 5 is the schematic diagram that is similar to Fig. 2, but show single cooling coil 61 with and operation method;

Fig. 6 and Fig. 8 are the schematic diagram of First Characteristic of the present utility model, and wherein the cooling coil of conventional business acrylonitrile reactor is than encapsulation more closely in conventional design;

Fig. 7 is the top view that is similar to Fig. 2 and Fig. 4, only shows and comprises that the folding of U-bend on these accessory and the upper U-bend of a cooling coil of the conventional design of these figure aligned with each other roll over accessory 63, on the line 7-7 of Fig. 7 in Fig. 5, intercepts;

Fig. 9 is the schematic diagram that can be used for the cooling coil of Fig. 6 and Fig. 8 to be suspended on the cooling coil suspender on its supporting structure;

Figure 10 is the schematic diagram of another feature of the present utility model, wherein thermal sleeve for the protection of the entrance of cooling coil and this cooling coil entrance through reactor wall joint; And

Figure 11 is the schematic diagram of another feature of the present utility model, is wherein repositioned onto the position lower than the top of these cooling coils for the outlet header that receives cooling water and steam from cooling coil.

Detailed description of the invention

According to First Characteristic of the present utility model, adopt the novel arrangement of cooling coil, it can be increased in the encapsulation of the cooling coil in reactor.As a result, the total surface area being provided by cooling coil assembly generally can increase effectively, and this causes again the better overall control of cooling coil operation then, and has caused at least in some cases the increase of total reactor capacity.

This feature is shown in Figure 6, and Fig. 6 is the schematic diagram that is similar to Fig. 4, and wherein it shows the layout of upper U-bend folding accessory 63 of each cooling coil 61, with and with respect to the layout of the cooling coil backbar 70 of passage 74 and cooling coil assembly.Also see Fig. 7, Fig. 7 schematically shows the layout of the coil pipe circuit in the conventional design of Fig. 2, Fig. 3, Fig. 4 and Fig. 5.By it, compared with Fig. 8, Fig. 8 is the schematic diagram that is similar to Fig. 7, but shows the layout of the cooling coil circuit in the design of the present utility model in Fig. 6.

As shown in Figure 6, the upper U-bend folding accessory 63 of cooling coil 61 relative to each other arranges with offset relationship, but not with coplanar relation as shown in Figure 4.In conventional design as shown in Figure 4, cooling coil 61 from the interior edge of reactor 10 vertically directed plane D extend to the periphery (, from position R to position S) of reactor 10.For convenience's sake, vertically directed plane D is referred to herein as the main cooling coil plane of cooling coil 61.As further shown in Figure 4, all major components of cooling coil 61 (, the cooling duct 60 of all vertically orientations and all lower U-bend folding accessories 62 and upper U-bend folding accessory 63) be all coplanar,, they all the heart or axis are positioned in the meaning in this plane with vertically directed main cooling coil plane D and aim at therein.This is further schematically illustrated in Fig. 7, the lower U-bend folding accessory 62 that Fig. 7 shows coolant guide pipe 60 and cooling coil circuit 57 therein in the heart or all meanings that are all arranged in public vertically directed main cooling coil plane D of axis with aligned with each other.In addition, as further shown in Figure 4, passage 74 is also arranged between these major components and is parallel to these major components.

But in the design of the change aspect this of the present utility model, at least some cooling coil circuits 57 of at least one cooling coil are arranged to generally be positioned at vertically directed main cooling coil flat transverse wherein with cooling coil.Generally speaking, all cooling coil circuits 57 of at least one cooling coil are all arranged in this way, and in certain embodiments, all cooling coil circuits in great majority or even all cooling coils are all arranged in this way.

This is arranged in Fig. 8 and more completely illustrates, Fig. 8 shows the coolant guide pipe 60 of each cooling coil circuit 57 of this design and lower U-shaped accessory 62 and is arranged in the corresponding cooling coil track plan Q of himself, and its vertically directed main cooling coil plane D that is arranged to be positioned at generally wherein with respect to cooling coil 61 acutangulates α.Sharp angle α can be the angle of any expectation.On the one hand, angle is between about 30 ° to about 60 °, and on the other hand between about 40 ° to about 50 °.

As further shown in Figure 6, the backbar 70 of the total weight of carrying cooling coil 61 and content thereof is positioned to higher than U-bend folding accessory 63, but not rolls over accessory lower than these U-bends as in the conventional design of Fig. 2, Fig. 3, Fig. 4 and Fig. 5.In addition, as shown in Figure 9, applicable supporting suspender is provided for each U-bend folding accessory 63 is suspended on its backbar 70 being associated.

The first advantage of the design of the change of this feature of the present utility model is the comparable encapsulation more closely in conventional design of cooling coil circuit 57.This makes the effective surface area of cooling coil assembly utilize this design to come to increase with respect to conventional design, the potentiality that this has then realized larger cooling capacity and had larger temperature of reactor control than conventional design again.Cooling coil design as herein described provides more cooling coil circuits at every meter of reactor diameter.In this regard, coil design as herein described for every meter of reactor diameter provide about 40 to about 60 cooling coil circuits and on the other hand every meter of reactor diameter provide about 45 to about 55 cooling coil circuits be effective.

The second advantage of the design of this change is can utilize this design to adapt to better than conventional design owing to regularly closing and restarting the mechanical stress of hardware giving to each cooling coil that forms this design.This is because the upper U-bend folding accessory 63 in design of the present utility model is suspended on supporting arm 70 by suspender, and is also arranged to supporting arm 70 horizontal.Therefore,, in the time that the cooling coil of design of the present utility model expands in response to variations in temperature and shrinks, give to these cooling coils than stress still less in other situation.This is because the signal portion of this expansion and contraction and these backbars laterally occur, and further because suspender is used as the bolster that absorbs the movement being associated occurring between change in size and these cooling coils and backbar.

Therefore, due to this design development, not only likely hold the required auxiliary equipment of this assembly (and particularly the number of passage and backbar) cooling capacity being provided by cooling coil assembly be provided in increase, but also likely eliminate or at least essence reduce generally owing to regularly closing and restarting the cooling coil fault that giving of causing to the mechanical stress of cooling coil occurs and the maintenance cost being associated.As noted, design as herein described provides more polydisc pipe.The less circulation continually of polydisc Guan Kegeng.

According to Second Characteristic of the present utility model, the cross-sectional area of the flow passage in the different cooling coils of cooling coil assembly of the present utility model is adjusted to the cooling water inflow that makes to be transformed into steam in each cooling coil assembly and has about 15% or less mean value, on the other hand, be about 10% to about 15%.What expect is, the total amount of the cooling water based on through cooling coil, these cross-sectional areas are selected such that to be transformed into the cooling water inflow of steam in all cooling coils in this cooling coil assembly and are not more than 5% with difference each other, what expect is to be not more than 4%, be not more than 3%, be not more than 2% or be not even greater than 1%.

As pointing out, cooling coil assembly can comprise cooling coil, at this place, each cooling coil includes the cooling coil circuit of different numbers.For example, cooling coil assembly can comprise cooling coil, and at this place, most of cooling coils have multiple cooling coil circuits (for example, 6 cooling coil circuits), and some cooling coils only have a cooling coil circuit.Removing of cooling coil realizes productivity ratio, and the cooling coil circuit of the different numbers that can remove in cooling coil circulation provides the operational flexibility for keeping the productivity ratio of expecting.

As shown in particularly Fig. 2, the general not all cooling coil circuit 57 all with similar number of different cooling coils in typical business acrylonitrile reactor.As a result, some in these cooling coils have longer flow passage, and other has shorter flow passage.This feature can cause the inhomogeneous operation of cooling coil, because the time of staying of the cooling water in longer flow passage no doubt can be greater than the time of staying of the cooling water in shorter flow passage.As a result, in longer flow passage than there being more cooling waters to be transformed into steam in shorter path.Higher flowing velocity in this flow passage that no doubt can cause more growing, especially near its port of export.This then can cause again the excessive erosion of inorganic matter in the cooling water of these positions and other composition and separate out (, precipitation and deposition).

As noted above, expectation be according to this feature of the present utility model, the quantity of steam generating in each cooling coil assembly has about 15% or less mean value, on the other hand, is about 10% to about 15%.That is to say, expectation be that the cooling water inflow that is transformed into steam in each cooling coil assembly is not more than water about 15% who is supplied to this cooling coil assembly, on the other hand, be about 10% to about 15%.Therefore, according to this feature of the present utility model, the cross-sectional area of the flow passage of each cooling coil is selected such that when all cut-off valves 84 are during in enable possition, the cooling water that is transformed into steam in individual channel will approach each other as far as possible at a value place, this value is about 15% or less, and be about 10% to about 15% on the other hand.In this regard, the quantity of steam of generation is calculated value.

The worthwhile mode of most of cost benefits of design business acrylonitrile reactor is to make each cooling coil by the pipe of same diameter, and controls each cooling coil with identical cut-off valve 84, that is, each control valve is identical with other.Therefore, region transversal of guaranteeing the flow passage of each cooling coil is selected to and realizes the simplest mode that water is transformed into steam is in the same manner that applicable constriction is positioned in each cooling coil, or at least in each cooling coil with shorter flow passage, expectation be its arrival end or its port of export or both places or near.The relative length of given different flow passages and therefore cooling water are by the different time length being present in these different paths, the accurate size (if or do not use constriction, determine the relative cross sectional area of flow passage) of determining each constriction can easily complete by conventional heat transfer calculations.

The 3rd feature of the present utility model has been shown in Figure 10.In conventional design as shown in Figure 5, the suction line 64 of cooling coil 61 is directly welded on the reactor wall 36 of reactor 10.As noted above, convention is the cooling coil " in turn " by regularly closing independently and continuously and then restart each cooling coil and make business acrylonitrile reactor.In the time that cooling coil is closed, its temperature is accumulated towards the normal operating temperature of reactor fast, about 350 DEG C to about 480 DEG C.Then,, when cooling coil is when contacting to restart with the cooling water of additional amount, the boiling point of this cooling water almost falls back or approaches in its temperature immediately.This cooling can give to cooling coil 61 thermal stress of essence, is especially welded to the position of reactor wall 36 at its suction line 64.Within a certain period of time, the thermal stress of this repetition can cause the mechanical breakdown of this position.

According to the utility model of this feature, this problem is crossed the position of the reactor wall 36 of reactor 10 and is avoided by thermal sleeve being arranged on to the suction line 64 of cooling coil 61.As shown in Figure 10, the thermal sleeve 59 being communicated with cooling coil suction line 64 is received in cooling coil inlet fitting 33, and this accessory 33 passes and is welded on the reactor wall 36 of reactor 10.The external diameter of thermal sleeve 59 is slightly less than the internal diameter of cooling coil inlet fitting 33, to limit heat space 75 therebetween, this heat space 75 is kept by shading ring 77.Therefore the Exit-edge of thermal sleeve 59, along 73 not welding or be otherwise permanently fastened on cooling coil accessory 33, and freely moves axially with respect to this cooling coil accessory.

Utilize this structure, in other cases any thermal stress on the mechanical splice appearing at when closing at it and restart between cooling coil suction line 64 and the reactor wall 36 that the essence variations in temperature in cooling coil 61 occurs is eliminated by expansion and the contraction of thermal sleeve 59.As a result, can avoid significantly crossing at it mechanical breakdown of the cooling coil 61 of the position of the reactor wall 36 of reactor 10.

According to another feature of the present utility model, be provided to reception and be repositioned onto the position lower than outlet line and the outlet header of each cooling coil through the coolant outlet collector of the cooling water and steam of each cooling coil.On the one hand, coolant outlet is repositioned onto the position lower than the top of the cooling coil circuit of each cooling coil.

As shown in Figure 5, in conventional design, coolant outlet collector 82 is positioned to higher than coolant outlet pipeline 79 and U-bend folding accessory 63, and it limits the top of cooling coil circuit 67,69 and 71.As noted above, the cooling coil of conventional business acrylonitrile reactor is regularly closed and is then restarted to remove any molybdenum incrustation that may be deposited on its outer surface.In the time closing cooling coil, any cooling water in remaining in is rapid evaporation because the temperature in acrylonitrile reactor is very high.In the time that this occurs, due to the outlet valve not being associated with outlet line 79, therefore causing the cooling water in outlet header 82, gravity flow back in this cooling coil of closing through cooling coil outlet line 79.This causes the cooling water evaporation of other additional amount, and is therefore transformed into the steam in cooling coil.

Cooling water generally comprises the inorganic matter of dissolving and additional processing chemicals.In the time that cooling coil is closed, these inorganic matters and processing chemicals are tending towards separating out and being deposited on the inner surface of cooling coil, particularly at lower U-bend folding accessory 62.If especially cooling coil was closed for a long time, these sedimental amounts may be essence, because this allows to flow back to from the cooling water of the essence additional amount of coolant outlet collector 82, and therefore from this cooling coil evaporation of closing.Within a certain period of time, this cross-sectional area (especially in these positions) that can cause the flow passage in cooling coil reduces significantly, and this causes increasing through the flow velocity essence of the cooling water of these positions.This can cause again the remarkable erosion of the cooling coil of these positions then, and therefore causes too early cooling coil fault.

According to this feature of the present utility model, this problem is by being repositioned onto coolant outlet collector 84 lower than the height of outlet line 79 and avoiding.On the one hand, outlet header is positioned to the top lower than the last cooling coil circuit of at least one cooling coil, is more contemplated to be the last circuit lower than great majority or even all cooling coils.On the other hand, outlet header is positioned to the top lower than all cooling coil circuits at least one coil pipe, is more contemplated to be the top lower than all cooling coil circuits in all cooling coils.See Figure 11, Figure 11 schematically shows these features.

Utilize this layout, due to coolant outlet pipeline 79 and go up on the one hand U-bend folding accessory 63 be positioned to higher than outlet header 82 too far away and can not make gravity that the cooling water flow of any significant amount is got back in the cooling coil of closing, therefore the cooling water that has substantially fully prevented additional amount backflow from coolant outlet collector 32 to the cooling coil of closing by gravity.

Although described only some embodiment of the present utility model above, it should be understood that and can in the situation that not departing from spirit and scope of the present utility model, carry out much remodeling.All this type of remodeling is all intended to be included in the scope of the present utility model being only limited by the appended claims.

Claims (4)

1. one kind for removing the hot cooling coil assembly being generated by oxidation reactor or ammonia oxidation reactor, described cooling coil assembly comprises multiple cooling coils, each cooling coil is all defined for flow of cooling water path, cooling water inlet and the coolant outlet carried through the cooling water at this place, each cooling coil also comprises the condensate water cutoff valve being associated with its cooling water inlet, each cooling coil is not also for controlling the valve through the cooling water flow of its coolant outlet, wherein, the length of at least some in described flow of cooling water path differs from one another

Wherein, to be selected such that to be transformed into the average percent of the cooling water of steam in this cooling coil assembly be 15% or less to the cross-sectional area of the described flow passage of each cooling coil assembly.

2. cooling coil assembly according to claim 1, is characterized in that, the average percent that the cross-sectional area of the described flow passage in each cooling coil assembly is selected such that to be transformed into the cooling water of steam in this cooling coil assembly is 10% to 15%.

3. cooling coil assembly according to claim 1, is characterized in that, the described cooling coil in described cooling coil assembly comprises at least three different lengths.

4. cooling coil assembly according to claim 1, it is characterized in that, described cooling coil is made by the conduit with identical diameter, some in wherein said cooling coil are shorter than other in described cooling coil, and those cooling coils wherein, with shorter length comprise that at their flow passage limited part is for controlling the percentage of the cooling water that is transformed into steam.