CN204373314U - One is applied to gas cryogenic separation equipment main distillation column - Google Patents
One is applied to gas cryogenic separation equipment main distillation column Download PDFInfo
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- CN204373314U CN204373314U CN201520002299.4U CN201520002299U CN204373314U CN 204373314 U CN204373314 U CN 204373314U CN 201520002299 U CN201520002299 U CN 201520002299U CN 204373314 U CN204373314 U CN 204373314U
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Abstract
One is applied to gas cryogenic separation equipment main distillation column, and it relates to a kind of main distillation column.This device comprises: take-off pipe, lower tower liquid nitrogen reflux pipe, low pressure heat exchanger, boiling section, heat exchanger and a main condenser evaporimeter in rectifying column main body, two pressure nitrogen gas towers.Under the utility model divides main distillation column according to sky, pressure tower nitrogen withdrawal amount affects the technical Analysis that air separation unit runs cold factor, for the not enough problem of pressure nitrogen gas taken amount, propose solution: 1) increase away from gas-liquid boiling section by the taking-up mouth of pipe, reduce drop and carry secretly; 2) change singly take out mouth as black soy sauce mouth minimizing exit velocity into.After transformation, reach the stable adjustment of empty point rectifying operating mode, operational factor meets design load, and under reduction main distillation column, the impact of tower fluctuation on ar system, eliminates low pressure heat exchanger low temperature stress fatigue and strength failure, add the object of the output of pressure nitrogen gas.
Description
Technical field
The utility model relates to a kind of main distillation column.
Background technology
Aqueous vapor subsidiary factory of China Coal Longhua, Harbin Coal Chemical Industry Co., Ltd. 4
#air separation unit, my company's 250,000 tons of methanol production line corollary equipments, adopt the KDON30000/24000 type air separation unit that Hangzhou Hangyang Joint-stock Co., Ltd produces, technological process is molecular sieve purification Internal-compression flow, be the most advanced technique of our times gas cryogenic separation, belong to large air separation plant.For supporting 250,000 tons of methanol production oxygen nitrogen amounts, Hangzhou Hangyang Joint-stock Co., Ltd of device fabrication producer is the manufacture of our factory amount body, by the novel oxygen generating plant that Hang Yang producer in advance oxygen generating plant KDON28000 type oxygenerator basis design and develop.Wherein pressure nitrogen gas 19500Nm
3/ h designs output can meet my chemical company's whole production line pressure nitrogen gas amount demand.Since in March, 2009, this complete equipment ran, lower pressure tower nitrogen cannot reach design output always, and pressure nitrogen is getting 10000Nm
3during/h, cooling box temperature is at 2 DEG C, and pressure nitrogen gas gives user after the heat exchange of low pressure heat exchanger, when sending nitrogen quantity more than 10500Nm
3during/h, pressure nitrogen gas cooling box temperature will drop to-17 DEG C gradually with the increasing of taken amount, and depart from former 23.5 DEG C ~ 2 DEG C normal design value, even if when this covering device 70% load operation, pressure nitrogen gas in proportion taken amount should at 13650Nm
310000Nm can only be got during/h
3the pressure nitrogen gas of/h.For avoid causing damage to low pressure heat exchanger and the race of device cold, pressure nitrogen gas taken amount is in the state of low discharge always, and this operating mode affects vapor liquid equilibrium in tower, to affect in rectifying column each section of reflux ratio, affect oxygen yield.Pressure nitrogen gas taken amount deficiency need open two nitrogen compressor replenish user demands in addition, pressure nitrogen gas does not reach design load for a long time, have impact on empty point normal rectifying operating mode, hinders long-period stable operation, run counter to the original intention of high load capacity cost declining, constrain factory's production capacity benefit development.
Utility model content
The utility model is for above-mentioned Problems existing, under dividing main distillation column according to sky, pressure tower nitrogen withdrawal amount affects the technical Analysis that air separation unit runs cold factor, for the not enough problem of pressure nitrogen gas taken amount, propose solution: 1) increase away from gas-liquid boiling section by the taking-up mouth of pipe, reduce drop and carry secretly; 2) change singly take out mouth as black soy sauce mouth minimizing exit velocity into.After transformation, reach the stable adjustment of empty point rectifying operating mode, operational factor meets design load, and under reduction main distillation column, the impact of tower fluctuation on ar system, eliminates low pressure heat exchanger low temperature stress fatigue and strength failure, add the object of the output of pressure nitrogen gas.
One of the present utility model is applied to gas cryogenic separation equipment main distillation column, and it comprises take-off pipe in rectifying column main body, two pressure nitrogen gas towers, lower tower liquid nitrogen reflux pipe, low pressure heat exchanger, boiling section, heat exchanger and a main condenser evaporimeter; Wherein, in two described pressure nitrogen gas towers, the gas outlet of take-off pipe is converged and is entered low pressure heat exchanger together, and in two pressure nitrogen gas towers, take-off pipe air inlet is placed in top of tower under rectifying column main body respectively; Described lower tower liquid nitrogen reflux pipe (3) one end is communicated with boiling section, and the other end is communicated with heat exchanger; Heat exchanger is arranged in main condenser evaporimeter; Wherein, in two pressure nitrogen gas towers take-off pipe at the mouth of pipe distance main condenser base of evaporator 50 ~ 60cm of the boiling section upper space of rectifying column main body.
The utility model comprises following beneficial effect:
The utility model improves as follows for air separation unit: 1) increase away from gas-liquid boiling section by the taking-up mouth of pipe, eliminates drop and carries secretly; 2) change singly take out mouth as black soy sauce mouth minimizing exit velocity into.
By above improvement, bring following advantage:
(1) secure context
By improving the height of pressure nitrogen conveying end and increasing the design of take-off pipe in a pressure nitrogen gas tower, reduce the flow velocity taking out gas, eliminate pressure nitrogen gas drop and carry phenomenon secretly, avoid the major safety risks causing low pressure heat exchanger and pipeline generation low temperature bursting by freezing harm.
(2) economic benefit aspect
Processed equipment fault, no longer underrun after pressure nitrogen gas normal supply, has saved the energy, has reduced power consumption, for further developing of our factory provides guarantee.The basis of each column:
1, a joint total value: 150.848 ten thousand yuan
Reduce by two nitrogen compressor operating costs:
250kwh × 0.29 × 2 × 8000h+22T/h × 0.15 × 2 × 8000h=150.848 ten thousand yuan
2, the new profit: 569.152 ten thousand yuan
New nitrogen pick-up output 3000Nm3/h × 8000h × 0.3=720 ten thousand yuan
720-150.848=569.152 ten thousand yuan.
Mentality of designing of the present utility model is as follows:
First, the utility model analyzes the low reason of pressure nitrogen gas temperature.According to the designing and calculating of Calculation of Heat Transfer basic mode determination low pressure heat exchanger heat exchange area, in addition on another stock of low pressure heat exchanger, tower dirty nitrogen reflux gas outlet temperature meets design load 23.5 DEG C, demonstrate the performance of this low pressure heat exchanger under design conditions no problem, eliminate the outer low factor of initiation pressure nitrogen temperature of rectifying column.
Secondly, second factor is exactly that pressure nitrogen gas carrys out gas quality, the drop that the pressure nitrogen conveying end position that Xia Ta top is drawn has sieve plate liquid layer to suspend and nitrogen together take out and are sent to low pressure heat exchanger, low pressure heat exchanger declines to the pressure nitrogen gas heat exchange efficiency containing drop, and this is the main cause causing pressure nitrogen gas cooling box temperature low.Pressure nitrogen gas returns to design discharge needs taking-up nozzle position, mode to transform, first promote 1.04 meters of pressure nitrogen gas and get tracheae height, increase the pressure nitrogen fairlead of a DN300 in main condenser evaporimeter 315 ° of directions simultaneously, and it is in parallel with original nitrogen pipeline, two pipes are got gas mode and are reduced the effect of getting gas velocity and carrying secretly to reach minimizing drop, and these two kinds of processing modes have recovered pressure nitrogen gas nominal situation.
Because the pipeline majority in cold insulated cabinet is cryogenic liquid or cryogenic gas pipeline, but their temperature levels is also different.In order to avoid unnecessary cold damage as far as possible, following item should be noted when pipe arrangement:
1) each pipeline must not be collided, and hot and cold tube should not lean on too near, and spacing should be greater than 100mm.Had better not be parallel to each other layout; 2) various liquid line or cold pipe should be tried one's best near inner cold containers, and gas piping is arranged in outside liquid line; 3) gas piping should in following scope from the distance (namely heat insulation layer thickness) of cold insulation tank wall :-50 ~-130 DEG C time, should be greater than 200 ~ 400mm;-130 ~-196 DEG C time, 300 ~ 600mm should be greater than; 4) liquid discharge tube road should be specifically noted that and prevents liquid from constantly gasifying and the cold damage increased.Fairlead should be inclined upwardly, and being about within the scope of 800mm near cold insulated cabinet the bend pipe made upwards, being highly about 6 ~ 10 times of diameters, but must not being less than 200mm.If there is irrational configuration, whole discharging tube is all filled with liquid, and near cold insulated cabinet shell place because temperature raises, liquid in pipe will gasify.Bubble moves upward and can return in container, continues again dirty with stylish liquid.So continuous round, have liquid constantly to gasify all the time in whole pipe, surrounding barrel shell temperature reduces, and produce cold frost, even bursting by freezing cold insulation casing, cold constantly loses.Comparatively reasonable disposition forms a fluid-tight when the valve is closed, liquid can stop valve side gasification.What have is added with sleeve pipe of heating, with anti-freeze to liquid discharge tube road; 5) in order to be reduced by the cold damage of pipeline and equipment supporter, the asbestos pad of heat conductivility difference should during installation, be added.
At the existing liquid nitrogen in air separation column top, have again gas nitrogen: we can see when boiling water, at atmosheric pressure, temperature is elevated to 100 DEG C, and water comes to life.But water is not all become steam quickly, but along with absorption heat, quantity of steam constantly increases.In the stage that vapour, liquid coexist, cry " saturation state ".Steam under this state is " saturated vapor ", and water is " saturation water ".At whole evaporation stage, steam and glassware for drinking water have identical temperature, so cry again " saturation temperature ".
The situation at rectifying column top is similar, and gas nitrogen and liquid nitrogen are in the saturation state coexisted, and has identical saturation temperature.But the saturated liquid at identical temperature and saturated vapor belong to different states.Saturated vapor releases hot condensable one-tenth saturated liquid, and temperature remains unchanged, and this part heat is called " condensation latent heat "; Saturated liquid absorption heat is annoying changes into saturated vapor, and it is constant that temperature also maintains saturation temperature, and this part heat is called " evaporation latent heat ".To same material, at the same pressure, the two numerically equal.
Affect the factor of exchanger heat transfer capacity (thermic load): fluid is a comparatively complicated process by the diabatic process of wall, and the factor affecting heat output is a lot.Experiment shows, heat output Q (being also thermic load) hourly is directly proportional to the temperature difference △ t (DEG C) of cold and hot fluid, with heat transfer area F (m
2) size be directly proportional, formulate is then
Q＝3600KF△t(kJ/h)
COEFFICIENT K in formula, heat transfer coefficient, represents that its unit is w/ (m when wall both sides fluid temperature difference is 1 DEG C by the heat-transfer capability of unit are
2dEG C).Heat transfer coefficient reflects all impact heat transfer various factors except heat transfer area F and temperature difference △ t.Obviously, energy saving is larger, represents that heat-transfer capability is stronger.Otherwise it is then weak.To the various heat exchangers arranged in air separation unit, its heat transfer area has been determined constant.
The brief introduction of the utility model relational language is as follows:
Rectifying column: rectifying column is also air separation column, when air rectifying, nitrogen constantly from liquid effusion enter gas, and oxygen constantly from gas condensation get off to enter liquid.This process occurs when gas and liquid comes into contact.Rectifying column is a kind of strengthening device, and it is by the effect of column plate, makes gas-liquid two-phase have sufficient attaching space, thus the exchange of strengthening heat and quality, finally air separation is become oxygen and nitrogen.
Boiling: liquid surface and the violent vaporization phenomenon of inner generation, is named boiling.The region being in this situation is boiling section
Reflux ratio: reflux ratio generally refers to the ratio of down-flowing liquid amount and rising vapor volume in tower, and it is also called liquid-gas ratio.And in Chemical Manufacture, reflux ratio generally refers to the ratio of down-flowing liquid amount and the overhead distillate scale of construction in tower.The purity of rectifying product, under the condition that the number of plates is certain, depends on the size of reflux ratio.The gas phase nitrogen purity obtained when reflux ratio is large is high, and Oxygen in Liquid purity is just low.The gas phase nitrogen purity that reflux ratio hour obtains is low, and the oxygen purity of liquid phase is just high.This is because the higher rising gas of the temperature down-flowing liquid lower with temperature mixes on column plate, after carrying out caloic exchange, their temperature can reach unanimity in the ideal case, namely reaches same temperature.This temperature is between original gas, liquid temp.If reflux ratio is large, when namely dirty cold liquid steam that is many or that rise is few, then gas-liquid mixed temperature must be partial to cryogenic liquid, so the temperature drop of rising steam is just large, steam condensing must be just many.Because oxygen is difficult volatile component, therefore oxygen components condense is got off corresponding also some more, and the nitrogen concentration leaving the uprising gas of column plate so also improves soon.Every block column plate is not always the case, therefore at the nitrogenous purity of the gas just height that tower top obtains.On the other hand, because gas-liquid mixed temperature is partial to cryogenic liquid, so the temperature rise of down-flowing liquid is just little, liquid evaporates also few, and the nitrogen component be thus evaporated in liquid is corresponding also less, leaves oxygen concentration in the down-flowing liquid of column plate like this and just improves slowly.Every block column plate is not always the case, and the oxygen concentration of the liquid thus obtained at the bottom of tower is just low.
Reflux ratio is hour then contrary with above-mentioned situation, the adjustment of rectifying operating mode, is exactly in fact mainly the size of the reflux ratio at each position in change tower.The rectifying tower temperature that operator often says is high, and reality just refers to that reflux ratio is little; Tower temperature is low, is exactly the large situation of reflux ratio.
Pressure nitrogen gas: pressure nitrogen gas is tower upper product under main distillation column, takes out mouth through pressure nitrogen and takes out, and sends into pipe network continuously, for rear line production and application after the just stream air heat-exchange after low pressure heat exchanger with purification as gas product.
The utility model content is not limited only to the content of the respective embodiments described above, and the combination of one of them or several detailed description of the invention equally also can realize the object of utility model.
Accompanying drawing explanation
Fig. 1 is existing rectifying tower structure schematic diagram:
Fig. 2 is the utility model rectifying tower structure schematic diagram.
Detailed description of the invention
Detailed description of the invention one: the one of present embodiment is applied to gas cryogenic separation equipment main distillation column, it comprises take-off pipe 2 in rectifying column main body 1, two pressure nitrogen gas towers, lower tower liquid nitrogen reflux pipe 3, low pressure heat exchanger 4, boiling section 5, heat exchanger 6 and a main condenser evaporimeter 7; Wherein, in two described pressure nitrogen gas towers, the gas outlet convergence of take-off pipe 2 enters take-off pipe 2 air inlet in low pressure heat exchanger 4, two pressure nitrogen gas towers together and is placed in rectifying column main body 1 time top of tower respectively; Described lower tower liquid nitrogen reflux pipe 3 one end is communicated with boiling section 5, and the other end is communicated with heat exchanger 6; Heat exchanger 6 is arranged in main condenser evaporimeter 7; Wherein, take-off pipe 2 50 ~ 60cm bottom the mouth of pipe distance main condenser evaporimeter 7 of boiling section 5 upper space of rectifying column main body 1 in two pressure nitrogen gas towers.
Detailed description of the invention two: present embodiment and detailed description of the invention one unlike: in two described pressure nitrogen gas towers, take-off pipe 2 lays respectively at rectifying column main body 1 time top of tower both sides.Other is identical with detailed description of the invention one.
Detailed description of the invention three: present embodiment and detailed description of the invention one unlike: in two described pressure nitrogen gas towers, take-off pipe 2 is increase 1.04 meters on the original basis and formed at the mouth of pipe of boiling section 5 upper space of rectifying column main body 1.Other is identical with detailed description of the invention one.
The beneficial effects of the utility model are verified by following examples:
Embodiment one
The structure of composition graphs 2 pairs of the present embodiment is described:
The gas cryogenic separation equipment that the is applied to main distillation column of the present embodiment, it comprises take-off pipe 2 in rectifying column main body 1, two pressure nitrogen gas towers, lower tower liquid nitrogen reflux pipe 3, low pressure heat exchanger 4, boiling section 5, heat exchanger 6 and a main condenser evaporimeter 7; Wherein, in two described pressure nitrogen gas towers, the gas outlet convergence of take-off pipe 2 enters take-off pipe 2 air inlet in low pressure heat exchanger 4, two pressure nitrogen gas towers together and is placed in boiling section 5 upper space of rectifying column main body 1 respectively; Described lower tower liquid nitrogen reflux pipe 3 one end is communicated with boiling section 5, and the other end is communicated with heat exchanger 6; Heat exchanger 6 is arranged in main condenser evaporimeter 7; Wherein, in two pressure nitrogen gas towers, take-off pipe 2 is increase 1.04 meters on original height at the mouth of pipe height of boiling section 5 upper space of rectifying column main body 1.
The present embodiment is centering coal dragonization Harbin aqueous vapor subsidiary factory of Coal Chemical Industry Co., Ltd 4
#air separation unit is the KDON30000/24000 type air separation unit produced by Hangzhou Hangyang Joint-stock Co., Ltd, through cutting gas, heating, replacing, taking off sand, measurement, drawing, improve, rectifying column king-tower mouthpiece is divided to sky according to modification scheme, promote 1.04 meters of pressure nitrogen gas and get tracheae height, increase the pressure nitrogen fairlead of a DN300 in main condenser evaporimeter 315 ° of directions, two kinds of measures reach the object reducing drop and carry secretly.When not having experience more not have suitability for industrialized production demonstration plant, successfully complete transformation in KDON30000/24000 large-scale space division device tower, transformation data and scientific research technology have promotional value in the same industry.
Before the present embodiment transformation, air separation unit can only send about 13500 pressure nitrogen gas to can not meet the needs of gas making, purification, methyl alcohol, sends to meet after technological requirement must open two nitrogen compressor force feeds, water, electricity that annual waste is a large amount of.After transformation in actual motion, reach the supply of air separation unit complete independently pressure nitrogen gas, flow reaches 19000, stable conditions.The investments such as equipment, technology, occupation of land have been saved in transformation, realize reducing the object that production cost saves energy consumption.From transforming equipment operational excellence so far.This transform innovation transformation as, and technique is promoted by existing Hangzhoupro oxygen, is widely used in more than 30,000 air separation units, in saving energy and reduce the cost in a sky point field, has good development prospect.
Claims (2)
1. be applied to a gas cryogenic separation equipment main distillation column, it is characterized in that it comprises take-off pipe (2) in rectifying column main body (1), two pressure nitrogen gas towers, lower tower liquid nitrogen reflux pipe (3), low pressure heat exchanger (4), boiling section (5), heat exchanger (6) and a main condenser evaporimeter (7); Wherein, in two described pressure nitrogen gas towers, the gas outlet of take-off pipe (2) is converged and is entered low pressure heat exchanger (4) together, and in two pressure nitrogen gas towers, take-off pipe (2) air inlet is placed in top of tower under rectifying column main body (1) respectively; Described lower tower liquid nitrogen reflux pipe (3) one end is communicated with boiling section (5), and the other end is communicated with heat exchanger (6); Heat exchanger (6) is arranged in main condenser evaporimeter (7); Wherein, take-off pipe (2) 50 ~ 60cm bottom mouth of pipe distance main condenser evaporimeter (7) of boiling section (5) upper space of rectifying column main body (1) in two pressure nitrogen gas towers.
2. one according to claim 1 is applied to gas cryogenic separation equipment main distillation column, to it is characterized in that in two described pressure nitrogen gas towers that take-off pipe (2) lays respectively at top of tower both sides under rectifying column main body (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520002299.4U CN204373314U (en) | 2015-01-04 | 2015-01-04 | One is applied to gas cryogenic separation equipment main distillation column |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520002299.4U CN204373314U (en) | 2015-01-04 | 2015-01-04 | One is applied to gas cryogenic separation equipment main distillation column |
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| CN204373314U true CN204373314U (en) | 2015-06-03 |
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| CN201520002299.4U Withdrawn - After Issue CN204373314U (en) | 2015-01-04 | 2015-01-04 | One is applied to gas cryogenic separation equipment main distillation column |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104534812A (en) * | 2015-01-04 | 2015-04-22 | 中煤能源黑龙江煤化工有限公司 | Main rectifying tower for gas cryogenic separation device |
-
2015
- 2015-01-04 CN CN201520002299.4U patent/CN204373314U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104534812A (en) * | 2015-01-04 | 2015-04-22 | 中煤能源黑龙江煤化工有限公司 | Main rectifying tower for gas cryogenic separation device |
| CN104534812B (en) * | 2015-01-04 | 2016-10-19 | 中煤能源黑龙江煤化工有限公司 | One is applied to gas cryogenic separation equipment main distillation column |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20150603 Effective date of abandoning: 20161012 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |