Background technology
At present, package printed matter generally is web-like, adopts intaglio press or flexible printing machine to print continuously usually, needs to need the printing product oven dry in printing product preheating, the printing process before the printing, needs the cooling printing after being completed for printing.
Existing printing machine comprises intaglio plate, gentle version, and oven dry adopts hot-air blowing to realize, is about to air heat post-purge printing and reaches the oven dry purpose, and pre-thermal recovery is finished with the oven dry similar fashion.Cooling adopts chill roll to finish mostly.
The preheating of existing printing machine, oven dry, cooling all exist complex structure, bulky, cost is high, energy consumption is excessive shortcoming, and drying plant also has the fatal problem of discharging waste gas, contaminated environment, has seriously restricted the sound development of industry.
As Figure 13, shown in Figure 14, existing printing machine drying system is made up of drying unit 10, hot air apparatus 40, connection airduct, exhaust system.Drying unit 10 comprises oven cover 20, base 50, is provided with printing inlet 03, printing outlet 04;
During work, printing 00 enters drying unit 10 through printing inlet 03, advances under backing roll 52 rolls support, dries after printing outlet 04 is left.Fresh air enters air intake passage 63 by new wind inlet 01, inlet air door 66 can be adjusted intake, enter 48 heating of air heater via and blower fan 30 pressurizations and back of air intake passage 63 by air-out passage 68, air taking port 46, air inlet 43 enters the inlet chamber 11 in the oven cover 20, purge the surface of the printing 00 of advancing continuously through nozzle 34 ejections, force liquid to be evaporated to steam and mix formation waste gas in back with air, waste gas enters discharge chamber 12 through air intake duct 42, again through exhaust outlet 44, return-air mouth 45 is got back to hot air apparatus 40, part is discharged into the atmosphere from waste gas outlet 02 through air exhaust passage 64, part is through return air channel 69, return air air door 67 mixes with the fresh air of air intake passage 63, heater via 48 heating and blower fan 30 pressurizations and back are by air-out passage 68 again, air taking port 46, air inlet 43 enters the inlet chamber 11 in the oven cover 20, thereby reduce the amount of fresh air that enters, reduce the energy consumption that adds hot-air.Adjusting inlet air door 66 and return air air door 67 can change the flow and the mutual ratio of air intake, return air.
Above-mentioned existing drying plant complex structure, owing to will obtain higher jet velocity, blower fan 30 all adopts centrifugal high pressure fan usually, cause inlet chamber to bear bigger pressure, need to adopt thicker steel plate to make, and then cause bulky, and the gas flow purging stroke is short, throughput is little, and drying efficiency is low, and then the lifting of the restriction equipment speed of service.Because gas can only adopt single bake out temperature with advancing with going out, and can't satisfy meticulous stoving process requirement, it is not saturating to select low bake out temperature then to dry, and select high bake out temperature then to occur the surface drying phenomenon easily, and energy consumption is huge.
Improvement project as above-mentioned drying plant oven dry performance and energy-conservation aspect, China utility model patent CN201214303Y discloses a kind of full-automatic circulation drier, comprise in the new wind air inlet and be provided with balance air door, new wind air inlet is by a three-way pipe, mixing bellows is communicated with heater, the outlet of heater is provided with the one-level blower fan, the one-level blower and pipeline is communicated with the baking oven of a side, the outlet of baking oven is communicated with the secondary blower fan by pipeline, the secondary blower and pipeline is communicated with the secondary baking oven, the outlet of baking oven is communicated with another three-way pipe by pipeline, this three-way pipe is communicated with the waste gas exhaust outlet, be provided with the waste discharge self closing door in the waste gas exhaust outlet, three-way pipe also takes back new wind air inlet by the pipeline that is provided with the circulation self closing door; Outlet at a back baking oven is provided with the LEL detector.The utility model can be realized energy-conservation in online detection, safety, environmental protection requirement; Be that heat energy has obtained effective utilization, saved the energy, improved the quality of printing effectively, waste discharge meets environmental protection requirement.
This utility model promote the oven dry performance, energy-conservation and secure context has tangible progress beyond doubt, but the complicated huge scope of using that limited undoubtedly of equipment, the progress of environmental protection aspect only limits to reduce the contribution that waste heat discharge is warmed to mitigation of global climate, there is no any progress aspect the pollution of solvent exhaust gas discharging.
A kind of improvement project as above-mentioned drying plant environmental protection aspect, use active carbon or activated carbon fiber that exhaust gas discharged is carried out adsorption treatment, most organic solvent in the waste gas can be reclaimed, reduce atmosphere pollution to a certain extent, and had certain economic benefits.But also there is following problem in this improvement project: 1, for the control device cost need reduce exhaust gas flow, cause hidden peril of explosion more outstanding; 2, in waste gas treatment process, also want the huge energy of additive decrementation, operating cost is higher; 3, active carbon or activated carbon fiber are consumptive material, need periodic replacement, cause cost to rise and influence production; 4, the desorption processing procedure can produce the water pollution; Equipment complexity, bulky takies the production site of more preciousness, and makes improvement project be subjected to more restriction; 5, be helpless to promote product quality and avoid production process affected by environment.
Relevant textbook and pertinent literature propose to adopt in drying plant condensation to reclaim the scheme that cooperates the closed cycle oven dry for the purpose of energy savings, and this type of scheme has obtained practice in the equipment of oven dry moisture.Chinese patent CN 101002991 discloses a kind of solvent reclaimer of loop circuit, the operation that the pressure fan that printing or painting device are established a calandria is dried for baking box, utilize air exhauster that heat exchanger, radiator and the condenser that the solvent that volatilizees is evacuated to reclaimer carried out three coolings again, make the solvent of volatilization carry out liquid gas and separate and be recovered in the condensation accumulator tank, and cold air promptly is sent to the pressure fan of evaporimeter, heat exchanger and calandria thereof and carries out three times and heat; Whereby, making the solvent of volatilization be able to store collected recycles in the condensation accumulator tank, and then the consumption of reduction solvent, gas with the volatilization in season can circulate and the anti-anxiety that leaks in this loop fully, pollute and air pollution with the water of avoiding the traditional printing device to be caused really, and then effectively improve environmental benefit and save the energy.
But analyse in depth the device structure complexity that this patent documentation discovery is provided, efficiency of energy utilization is low, lacks good cooperating with process equipment, and equipment cost and operating cost are all very high, makes this patent documentation lack practicality.
In sum, existing drying plant has following shortcoming: 1, oven dry gas is difficult to satisfy the stoving process requirement with advancing with going out.2, the gas flow purging stroke is short, and throughput is little, and drying efficiency is low, and casing is long, and the control difficulty is big.3, Btu utilization efficient is low, and energy consumption is excessive, the operating cost height.4, the air channel complex interface is many, and gas easily leaks, and fan noise is big, and the feature of environmental protection is poor.5, complex structure, huge heaviness, expend great deal of steel, the manufacturing cost height.6, installation and transportation trouble, expense height, it is big to take the factory building space.7, organic solvent is harmful to human body and environment, and directly discharging causes polluting.8, exist the utmost point that the organic solvent of economic worth and a large amount of heats are arranged in the waste gas, can not make a silk purse out of a sow's ear causes producing exorbitant expenditure, and processing benefit descends.9, for reduce add hot-air energy consumption just needs reduce the flow of fresh air, but there is serious potential safety hazard in the concentration that can cause organic steam above the explosion limit accident of blasting.10, adopt natural air in a large number, make processing be limited by climatic environment, when ambient air temperature was low, it was huge to heat required energy consumption, even can't satisfy the oven dry needs and cause stopping production.11, the dust in the natural air influences the crudy of product.
Summary of the invention
Purpose of the present invention, be for a kind of energy-saving and environment-friendly printer is provided, by at preheating, oven dry, the recycling air of cooling link, heat, solvent, reach cut down the consumption of energy, the purpose of pollution abatement, have the characteristics of compact conformation, superior performance, flexible and changeable, energy-conserving and environment-protective.
Purpose of the present invention can reach by following technical solution:
Energy-saving and environment-friendly printer comprises printing element, and printing element comprises drying unit, and its design feature is:
1) described drying unit comprises oven cover, base, and it also is provided with printing inlet, printing outlet; Described oven cover is provided with drying cavity and the recycling cavity that is interconnected, and forms the air-flow circulation canal;
2) in oven cover, be provided with blowing unit, heat pump condenser, refrigerating evaporator, constitute one have air-supply, heat, the device of refrigerating function; Described blowing unit is installed in the drying cavity, and described blowing unit comprises blower fan, is provided with air intake passage, air exhaust passage, air-out passage, constitutes the gas purging and the circulatory system; Heat pump condenser is installed in the blowing unit, is used for heated air and produces hot blast realization oven dry purpose; Refrigerating evaporator is installed in the recycling cavity, is used to reclaim heat condensing solvent steam and reaches the waste gas inter-process.
That the progressive part of content of the present invention has been to provide is simple and compact for structure, oven dry performance brilliance, can realize the drying unit that gas, heat, solvent three recirculate, make printing machine no longer need complicated huge air supplying and exhausting system and emission-control equipment, easily realization is energy-conservation more than 60%, the target for energy-saving and emission-reduction of reducing discharge of waste gases 100%.
Purpose of the present invention can also reach by following technical solution:
A kind of embodiment of the present invention is: described oven cover also comprises outer cover part, partition component, frame parts; Drying cavity is surrounded by partition component, frame parts and base, and recycling cavity is surrounded by partition component, frame parts and outer cover part.
A kind of embodiment of the present invention is: described oven cover comprises at least six blowing units, described at least six blowing units are arranged along printing inlet order before and after the printing Way out, and the air intake passage of last blowing unit links to each other with the air exhaust passage of back one blowing unit; Drying unit is provided with low-temperature zone, middle-temperature section, high temperature section, cooling section along the printing inlet to the printing Way out.
A kind of embodiment of the present invention is: described oven cover also comprises new aerofoil, inlet air door, return air air door; High temperature section comprises new aerofoil and inlet air door, establishes new wind passage between cooling section and the middle-temperature section, and described new wind passage is surrounded by new aerofoil and partition component.
A kind of embodiment of the present invention is: described frame parts comprises left wallboard, right wallboard, and described left wallboard, right wallboard are provided with air vent; Described blower fan also comprises deflector, stabilier, through-flow impeller; Described partition component, new aerofoil, deflector, stabilier, through-flow impeller, inlet air door, return air air door all are assemblied on left wallboard and the right wallboard.
A kind of embodiment of the present invention is: described printing machine also comprises preheating unit, can implement preheating guarantee printing quality by printing product; Described preheating unit comprises preheating lid, base, is provided with printing inlet, printing outlet; The preheating lid comprises blowing unit, condenser, adopts heat pump to heat the reduction energy resource consumption; Blowing unit comprises blower fan, and the internal fan simplified structure improves air-supply and purges efficient; Condenser is installed in the blowing unit, and the gas circulation path is short, heat exchange and purging efficient height.
The preheating device that progressive part of the present invention has been to provide simple and compact for structure, energy resource consumption is low.
A kind of embodiment of the present invention is: described printing machine also comprises cooling unit, can printing product enforcement cooling prevent contraction distortion; Described cooling unit comprises cooling lid, base, is provided with printing inlet, printing outlet; The cooling lid comprises blowing unit, evaporimeter, adopts cold air to strengthen cooling effect; Blowing unit comprises blower fan, and the internal fan simplified structure improves air-supply and purges efficient; Evaporimeter is installed in the blowing unit, and the gas circulation path is short, heat exchange and purging efficient height.
That the progressive part of content of the present invention has been to provide is simple and compact for structure, use cold air to strengthen the cooling device of cooling effect.
A kind of embodiment of the present invention is: described cooling unit also comprises choke valve, compressor, and compressor, condenser, choke valve, evaporimeter, compressor link to each other successively.It is the shared same refrigerating and heating systems of preheating unit and cooling unit, utilize the condenser release heat to obtain cold, be delivered to evaporimeter, utilize the evaporimeter released cold quantity to absorb heat by refrigerating and heating systems, with the heat transferred condenser, realized the recycling of cold heat again.
The progressive part of content of the present invention is the recycling different demands that satisfy preheating and cooling simultaneously of heat, and energy-saving effect is more remarkable.
The invention has the beneficial effects as follows:
1, the present invention at first transforms drying plant, broken the whole up into parts in original external air intake blower fan, heater and air channel, adopt small and exquisite blower fan to be built in the oven cover, substitute the air channel of original complex structure and function singleness by inner dexterous air channel, the effect that obtains compact conformation, saves space and minimizing material consumption, and the realization closed cycle, for the solvent condenses retracting device provides suitable installing space.On structure improved basis, adopt heat pump to satisfy oven dry and heat demand and condensation recovery refrigeration demand.By air flow direction, add the hierarchical arrangement of heat, throughput, obtain meticulous stoving process adaptive capacity, reach the target that improves dries quantity and cut down the consumption of energy; Utilize heat pump to provide heat energy to obtain higher heat pump efficiency coefficient by minute grade, avoid or reduce and utilize high-grade heat energy; Further change waste gas condensation recovery process again, improve coefficient of refrigerating performance, enlarge the scope of application of heat pump.The cold air recovery heat, improvement equipment working environment, the minimizing equipment that utilize removal process to produce externally dispel the heat.At last, reach zero toxic emission, energy-conservation target for energy-saving and emission-reduction more than 60%.Use the drying plant realization preheating and the cooling of circulation in realizing, utilize heat pump to produce hot blast and cold wind simultaneously, satisfy the needs of preheating and cooling respectively, further reach energy-conservation target.
2, printing machine provided by the present invention not only structure simplify greatly than legacy equipment, occupation area of equipment significantly reduces, manufacturing cost and installation and transportation expense significantly descend, and the oven dry performance significantly promotes, printing is avoided dust pollution in the environment, can also realize energy-conservationly more than 60%, eliminate exhaust emission fully, its social benefit and economic benefit are very remarkable.Inspired by the present invention and based on this, those skilled in the art can carry out various improvement to the design of existing product.
The specific embodiment
Specific embodiment:
Fig. 1 to Figure 12 constitutes a specific embodiment of the present invention.
Present embodiment is the solvent-borne type intaglio press.
Wherein, Fig. 1 to Fig. 8 provides the detailed structure of the used drying unit of present embodiment, and Fig. 9 provides present embodiment drying unit adapted heat pump assembly schematic diagram.
Below in conjunction with accompanying drawing in detail example of the present invention is described in detail:
The corresponding relation of component names and Reference numeral is as shown in table 1 in each accompanying drawing.
Table 1: component names and Reference numeral correspondence table
00—— 10—— 20——01—— 11—— 21——02—— 12—— 22——03—— 13—— 23——04—— 14—— 24——220—— 16—— 25——320—— 17—— 26——18—— 27——19—— 28——29——30—— 40—— 50——31—— 41—— 51——32—— 42—— 52——33—— 43——34—— 44—— 70——38—— 45——39—— 46——47——48——49——60—— 80—— 93——61—— 81—— 96——62—— 82—— 97——63—— 83—— 98——64—— 85—— 99——66—— 86—— 288——67—— 87—— 396——68—— 88—— 397——69—— 89—— 399—— |
As shown in Figure 1 and Figure 2, drying unit 10 comprises oven cover 20, base 50, is provided with printing inlet 03, printing outlet 04.
Base 50 comprises base housing 51 and backing roll 52.Printing 00 enters from printing inlet 03, and the wind-force of accepting blowing unit 60 under backing roll supports purges, and drying unit 10 is left by printing outlet 04 in the oven dry back.
Oven cover 20 comprises outer cover part 21, partition component 22, frame parts 23, nine blowing unit 60A~60I, a cycling element 41, is provided with drying cavity 13, recycling cavity 14; Drying cavity 13 is surrounded with base 50 by partition component 22, frame parts 23, and recycling cavity 14 is surrounded with outer cover part 21 by partition component 22, frame parts 23, and drying cavity 13 is interconnected with recycling cavity 14 two ends, forms the gas passage of inner loop oven dry.
As shown in Figure 3, blowing unit 60 comprises blower fan 30, is provided with air intake passage 63, air exhaust passage 64, air-out passage 68, and blowing unit 60 is installed in the drying cavity 13; Blower fan 30 is cross flow fans, comprises deflector 31, stabilier 32, through-flow impeller 33.Oven cover 20 also comprises the cycling element 41 that is installed in the drying cavity 13, cycling element 41 comprises blower fan 30 and return air air door 67, cycling element 41 can overcome the recovery approach windage and guarantee the global cycle air quantity, can avoid drying gas and leak, can adjust return air air door 67 according to the oven dry demand and change the global cycle air quantity from printing inlet 03.
Nine blowing units 60 are arranged along printing inlet 03 order before and after printing exports 04 direction, and the air intake passage 63 of last blowing unit 60 links to each other with the air exhaust passage 64 of back one blowing unit 60, and 64E links to each other with 63F as shown in FIG..
Adopt the laterally cross flow fan of air-supply, blowing unit 60 is built in the oven cover 20, broken through the restriction of legacy equipment, make structure become simple compact, stoving process improves, and drying effect is significantly improved.
As shown in Figure 9, heat pump assembly 80 is a kind of perfect and unique cascade type heat pump systems, can realize under higher Energy Efficiency Ratio that system's evapo tranpiration temperature and total condensation temperature difference reach the effect of 130K, make drying unit that present embodiment provides 10 can finish the dual role of oven dry and solvent recovery efficiently.Heat pump assembly 80 comprises heat pump compressor 89, heat pump cooler 83, heat pump condenser 88, heat pump subcooler 82, heat pump choke valve 87, evaporator with heat pump 86, evaporative condenser 85, the heat pump compressor 89 that links to each other successively and the refrigeration compressor 99 that links to each other successively, evaporative condenser 85, refrigerant condenser 98, choke valve 97, refrigerating evaporator 96, refrigeration compressor 99 freeze.
Heat pump subcooler 82, heat pump cooler 83, heat pump condenser 88, evaporator with heat pump 86, refrigerating evaporator 96, refrigerant condenser 98 are the heat exchanger of copper pipe cover aluminium fin.
Heat pump condenser 88, heat pump cooler 83, heat pump subcooler 82 are installed in the drying cavity 13, and evaporator with heat pump 86, refrigerating evaporator 96, refrigerant condenser 98 are installed in the recycling cavity 14.Below refrigerating evaporator 96, be provided with liquid trap 93, collect the solvent that is condensed into liquid, flow in the concentrated outward solvent container of equipment by reclaim line.
Heat pump condenser 88 is used to add hot-air dries, and refrigerating evaporator 96 is used to reclaim latent heat and condensing solvent steam, obtains energy-conservation simultaneously and effect environmental protection.After adopting evaporative condenser 85, also used evaporator with heat pump 86 to realize that sensible heat reclaims, reduce low temperature level refrigeration demand; It is cold also to use refrigerant condenser 98 to realize, improves the efficient of low temperature level refrigeration, obtains higher coefficient of refrigerating performance, has widened the adaptability of 80 pairs of oven dry of heat pump assembly demand.
Heat pump compressor 89 is discharged in the Compressed Gas and is comprised sensible heat and latent heat, and sensible heat is presented as that delivery temperature is higher than condensation temperature, and the calorific value of sensible heat is little but of high grade, and sensible heat accounts for 20%~35% of total heating capacity usually in heat pump, and delivery temperature can be up to 130 ℃.Adopt the purpose of heat pump cooler 83 to be difference use sensible heat and latent heat, can under the situation that does not improve condensation temperature, obtain the highest bake out temperature between condensation temperature and delivery temperature.The highest bake out temperature of printing machine demand generally is higher than 80 ℃, and the condensation temperature during the economic reliability service of heat pump generally is no more than 65 ℃, adopt heat pump cooler 83 to cooperate the control of air quantity both can satisfy the demand of high bake out temperature, and needn't sacrifice the economy or the compressor life-span of operation.
Fig. 9 also provides the reference value of working medium and oven dry gas temperature, and temperature is the temperature that working medium passes in and out these parts in the picture frame, and dotted line is oven dry gas flow process, and picture frame external standard temperature indicating degree is the flow through turnover temperature of these parts of oven dry gas.As can be seen, the condensation temperature of high temperature level is 65 ℃, and maximum subcooled temperature is 25K, and evaporating temperature is 10 ℃, and the degree of superheat is 5K; Low temperature level condensation temperature is 20 ℃, and maximum subcooled temperature is 50K, and evaporating temperature is-40 ℃, and the degree of superheat is 50K.The highest bake out temperature that equipment can provide can surpass 80 ℃, can satisfy the demand of printing oven dry.
As shown in Figure 4, drying unit 10 exports 04 direction along printing inlet 03 to printing and is provided with low-temperature zone 16, middle-temperature section 17, high temperature section 18, cooling section 19.
Low-temperature zone 16 comprises blowing unit 60H, 60I and heat pump subcooler 82H, 82I.Middle-temperature section 17 comprises blowing unit 60E, 60F, 60G and heat pump condenser 88E, 88F, 88G, and high temperature section 18 comprises blowing unit 60B, 60C, 60D and heat pump cooler 83B, 83C, 83D, and cooling section 19 comprises blowing unit 60A.
With reverse air-supply drying mode segmentation oven dry, utilize heat pump condenser 88, heat pump cooler 83, heat pump subcooler 82 to realize different bake out temperatures, disposed drying heater in the drying unit 10 by perfect stoving process demand, adopted cooling section to reclaim heat and realized further energy-conservation and perfect technology.
High temperature section 18 is provided with new aerofoil 28 and inlet air door 66, establishes new wind passage 62 between cooling section 19 and the middle-temperature section 17, and described new wind passage 62 is surrounded with partition component 22 by new aerofoil 28.Inlet air door 66 cooperates with heat pump cooler 83 can obtain stoving process the highest required bake out temperature.New wind passage 62 set up the heat exchange efficiency that has improved heat pump condenser 88, make heat pump assembly 80 can obtain higher Energy Efficiency Ratio.
As Fig. 5~shown in Figure 7, oven cover 20 also comprises blower motor 38 and driving belt 39, and blower motor 38 is installed in the recycling cavity 14, drives all blower fans 30 by driving belt 39.Blower motor 38 is installed in and can reduces the operating temperature of blower motor 38 in the recycling cavity 14 and reclaim the heat that it distributes.
Frame parts 23 comprises front beam 24, rear cross beam 25, left wallboard 26, right wallboard 27.
Left side wallboard 26, right wallboard 27 are provided with pilot hole, partition component 22, new aerofoil 28, deflector 31, stabilier 32, through-flow impeller 33, inlet air door 66, return air air door 67, heat pump cooler 83, heat pump condenser 88 all are assemblied on left wallboard 26 and the right wallboard 27 by angle Support, and this is a kind of succinct standard assemblied organization plan.
Left side wallboard 26, right wallboard 27 are provided with air vent 29, and every side comprises 2 macropores that communicate with new wind passage 62, and the gas lower for temperature flows out; Also comprise 5 apertures that communicate with middle low-temperature zone blowing unit air intake passage 63, flow into for cryogenic gas.The gas channel that cryogenic gas forms between left and right sidesing wall plate and outer cover part flows, and has both played preventing that drying unit 10 from externally dispelling the heat, and avoids rotatable parts temperature such as bearing too high again.
Shown in 33J among Fig. 6, difference apart from right wallboard 27 distances is 33 millimeters to impeller edge, through-flow impeller 33 left side apart from left wallboard 26 distances and impeller edge, right side, the asymmetric setting of through-flow impeller 33 realized gas flow in the base 50, improved the coefficient of heat transfer of printing 00 with oven dry gas.
As shown in Figure 8, heat pump assembly 80 also comprises heat pump cabinet 81 and control device 70, and heat pump compressor 89, control device 70, refrigeration compressor 99, evaporative condenser 85 are installed in the source pump case 81.Heat pump choke valve 87, refrigeration choke valve 97 all are installed in the oven cover 20 nearby, and each parts of heat pump assembly 80 connect by copper pipe.
In the present embodiment, refrigeration choke valve 97 adopts capillary, and heat pump choke valve 87 is electromagnetic expanding valves, and heat pump compressor 89 is frequency-changeable compressors; Inlet air door 66, return air air door 67 are stepper motor driven MOD; Control device 70 comprises temperature sensor and solvent strength sensor, and sensor is installed in the oven cover 20; The control of heat pump choke valve 87, inlet air door 66, all controlled device 70 of return air air door 67.Drying unit that present embodiment provides 10 can adapt to the oven dry changes in demand automatically.
Drying course along printing 00 direct of travel is as follows:
Printing 00 enters from printing inlet 03, and the wind-force of accepting blowing unit under backing roll supports purges.After entering drying unit 10, at first accept the gas flow purging of recommending of blowing unit 60I and cycling element 41 formation, gas is about 35 ℃ of temperature, wherein solvent steam concentration is higher, solvent partly evaporates in the entrained gas on the printing 00, and the gas that is full of solvent vapo(u)r is recycled unit 41 and sends into recycling cavity 14;
Printing 00 is passed through blowing unit 60H, 60G, 60F, 60E successively, and the oven dry gas temperature is respectively about 45 ℃, 50 ℃, 55 ℃, 60 ℃, during this period, the solvent evaporation on the printing more than 80%, the temperature of printing 00 rises.
Printing 00 enters blowing unit 60D, 60C, 60B accepts high temperature and purges, and each unit oven dry gas temperature is approximately 70 ℃, 75 ℃, 80 ℃.High temperature purges residual solvent is evaporated fully, and the temperature of printing 00 continues to rise.
Printing 00 enters blowing unit 60A and accepts about 15 ℃ cryogenic gas purging, the temperature difference of gas and printing 00 is bigger, and heat transfer intensity is higher relatively, and gas temperature rises to about 25 ℃ after the heat exchange, leave drying unit 10 from printing outlet 04 after printing 00 is cooled and lowers the temperature, finish drying course.
The course of work along the oven dry gas flow direction is as follows:
Following process is to be ethyl acetate at solvent, under the situation of total solvent oven dry amount 5g/s.
About 15 ℃, solvent steam concentration be 0.26% (vol, percentage by volume, down with) gas enter blowing unit 60A, through being warmed up to about 25 ℃ the essentially no variation of solvent steam concentration after the cycle purge printing 00.
Distribute through inlet air door 66, gas divides two-way to enter high temperature section 18 and middle-temperature section 17 respectively.
The new wind flow that enters high temperature section is very little, and wherein part flows into blowing unit 60B and is heated to 80 ℃ or higher by heat pump cooler 83.By the portion gas after the 60B heating and the 60C that flows through after the new wind that does not flow to 60B mixes, part is sucked and is heated to about 75 ℃ by 60C, equally, by the portion gas after the 60C heating with flow to 60D after the mist that does not flow to 60C mixes again, heat to about 70 ℃ through the 60D circulation, the gas in part discharge and the new wind passage 62 is mixed into middle-temperature section 17.Because the quantity of solvent in high temperature section oven dry evaporation is little, mix behind the new wind that the concentration of solvent vapo(u)r just slightly improves in the gas, greatly about about 0.3%.
The gas that enters middle-temperature section is under the heating of heat pump condenser 88, temperature is between 55~60 ℃, solvent evaporates in a large number during this period, solvent steam concentration rises to about 0.5% in the gas, solvent evaporation and printing 00 temperature rise and have absorbed the heat of heat pump condenser 88 dispensings, the temperature that gas is entered after the low-temperature zone drops to about 45 ℃, in low-temperature zone, though temperature is lower, the exposed area of solvent is big on the printing 00, so evaporation rate is also very fast, heat pump subcooler release heat is slowed down decrease of temperature.The concentration of solvent rises to about 0.7% at last in the gas, is equivalent to 30% of lower explosive limit LEL2.2%.
The gas temperature of sending into recycling cavity 14 through cycling element 41 about about 35 ℃, enters refrigerating evaporator 96 and continues cooling greatly after cooling to 15 ℃ behind the evaporator with heat pump 86 recovery section sensible heats.The evaporating temperature of refrigerating evaporator 96 is-40 ℃, but the degree of superheat of latter end is higher, and purpose is to improve the condition of work of refrigeration compressor.Gas is reverse heat-exchange in refrigerating evaporator 96, and solvent vapo(u)r wherein constantly is condensed into liquid and flows to liquid trap 93, and gas cools to about-35 ℃ at last, and the concentration of solvent vapo(u)r is reduced to the saturated concentration 0.26% under this temperature.Subsequently, gas enters heat pump condenser 98 reverse heat-exchanges and is warmed up to 15 ℃, leaves recycling cavity 14 and enters the process that drying cavity 13 is finished the oven dry gas circulation.
Because the sensible heat of the latent heat of solvent evaporation and gas heating all is recovered utilization, the power that drying unit that present embodiment provides 10 compressors and blower fan consume should equal the heat energy that equipment dispels the heat to environment and printing 00 heats up and consumed.Since oven cover 20 adopt the new vane of low temperature around the insulation measure, in most cases not only can not dispel the heat to environment, also can from environment, absorb heat, base 50 is if take simple heat insulation measure, should reach thermal balance basically between drying plant and the environment, the main body that absorbs heat is a printing 00.Owing to increased the heat of cooling section 19 recovery printings 00, and be subjected to the restriction of the coefficient of heat transfer, heat exchange area and heat-exchange time, the heat that printing 00 absorbs is very limited, even be low to moderate at operating ambient temperature under 0 ℃ the extreme case, 1.3 the printing element of rice width uses the required oven dry electric power of baking oven that present embodiment provides to have only about 5kw, compare with existing drying plant, energy-conservation up to 80%.And under extreme case, legacy equipment can't satisfy the demand of oven dry at all, and northerly performance in winter is particularly outstanding.
Figure 10 is the preheating lid generalized section of the embodiment of the invention 1.
Preheating device is made up of preheating lid 220 and base 50, and preheating lid 220 has adopted 9 blowing unit 60A~60I, and each blowing unit 60 all is equipped with condenser 288, constitutes relatively independent hot air circulation preheating device.Base 50 is used identical with drying unit 10, is provided with printing inlet 03, printing outlet 04 equally; The structure of preheating lid 220 is except that ducting system is simple, and all the other each parts and oven cover 20 are also roughly the same, so repeat no more.
Figure 11 is the cooling lid generalized section of the embodiment of the invention 1.
Cooling device by cooling cover 320 and base 50 form, cool off and to cover 320 and adopted 9 blowing unit 60A~60I, each blowing unit 60 all is equipped with evaporimeter 396, constitutes relatively independent cold wind cooling back installation.Base 50 is used identical with drying unit 10, is provided with printing inlet 03, printing outlet 04 equally; Cooling cover 320 structure except that ducting system simply, all the other each parts and oven cover 20 are also roughly the same, so repeat no more.
Figure 12 is the pre-apparatus for cooling refrigerating and heating systems schematic diagram of the embodiment of the invention 1.
Compressor 399, condenser 288, choke valve 397, evaporimeter 396, compressor 399 link to each other successively.Be preheating unit 200 and cooling unit 300 shared same refrigerating and heating systems, utilize condenser 288 release heat to obtain cold, be delivered to evaporimeter 396 by refrigerating and heating systems, utilize evaporimeter 396 released cold quantities to absorb heat, with heat transferred condenser 288, realized the recycling of cold heat again.
The obvious improvement part of printing machine provided by the present invention is that preheating, oven dry, cooling performance are good, floor space is polluted, reduced in zero toxic emission, full solvent recovery, low energy expenditure, low noise, easily transportation is installed, and the present invention can bring bigger social benefit and economic benefit.