Background technology:
Lithium-bromide absorption-type refrigerating machine is that a kind of the driving by heat energy moved, with water is that cold-producing medium, lithium bromide water solution are absorbent, under vacuum state, produce air conditioning or technology refrigeration plant with cold water, but the heat that its driving heat source steam, hot water or combustion fuel (fuel oil, combustion gas) produce.The heat that produces with combustion fuel is that the direct-burning type lithium bromide absorption type refrigeration machine of driving heat source can be designed and manufactured into the unit of producing cold water separately, also can be designed and manufactured into the unit that replaces or produce cold water, hot water simultaneously, thereby corresponding again direct-fired lithium bromide absorption type cold water, the hot and cold water unit of being called; With steam, hot water is that the lithium-bromide absorption-type refrigerating machine of driving heat source has only refrigerating function, thereby corresponding steam type lithium bromide absorption cold water unit and the hot water type lithium bromide absorption cooling water unit of being called.The direct-burning type lithium bromide absorption type refrigeration machine generally all is the dual effect type unit, and the hot-water type refrigeration machine mostly is the single-action unit, and the steam type refrigeration machine has the dual effect type unit, and the single-effect type unit is also arranged.
During the lithium-bromide absorption-type refrigerating machine refrigerating operaton, prevent that cold water in its parts or water as refrigerant Yin Wendu from crossing low and glaciation causes fault, the frozen pipe that freezes of the cold water in the device heat exchanger tube that especially avoids evaporating is an important safe operation control target.Lithium-bromide absorption-type refrigerating machine freezing proof technique measure in the past is to be provided with on cold water outlet temperature sensor 11 and the water as refrigerant liquid capsule 13 at evaporimeter respectively water as refrigerant temperature sensor 14 is set on the cooling water outlet pipe 12 of the evaporimeter 10 of unit (shown in Figure 1).The control system (not shown) of unit detects cold water outlet temperature and water as refrigerant temperature by temperature sensor in good time, when cold water outlet temperature or water as refrigerant temperature reach the relevant temperature lower limit of setting in the control program, control system is by stopping cryogenic fluid pump 15 and cutting off the driving heat source of unit, make unit stop refrigeration, stop cold water outlet temperature further to descend, thereby reach the safe operation control purpose that prevents the unit frozen pipe.
Lithium-bromide absorption-type refrigerating machine evaporimeter frozen pipe, be because under situations such as underload or cooling water low temperature, hypotony in the absorber, pressure in the evaporimeter is dropped to≤4.58mmHg (the pairing saturation pressure of 0 ℃ water), thus make cold water temperature in the evaporimeter heat exchanger tube be reduced to≤0 ℃ due to.Because there is hysteresis quality in temperature detection, the running temperature of unit changes when existing thermal inertia, control system to carry out antifreeze control program, and the cold water outlet temperature of unit often has been lower than preset lower limit.After control system is carried out antifreeze control program, the cold water outlet temperature of unit still can continue certain numerical value that descends, also can rest on a certain temperature value long period that is lower than preset lower limit even do not continue to descend, and can in the short time (as 1 minute), oppositely not rise.Therefore, freezing proof technique measure in the past only to the control of the safe operation under unit cold water outlet temperature and the slowly decline situation of water as refrigerant temperature effectively, then powerless because of cold water outlet temperature or the rapid decline of water as refrigerant temperature that the reasons such as decline fast or the quick reduction significantly of cooling water temperature of loading cause for unit, this situation tends to cause unit generation frozen pipe fault.
Summary of the invention:
The objective of the invention is to overcome above-mentioned deficiency, a kind of lithium-bromide absorption-type refrigerating machine that has generator refrigerant vapour regulating and antifreezing installation that can both prevent the icing frozen pipe of unit under any service condition is provided.
The object of the present invention is achieved like this: a kind of lithium-bromide absorption-type refrigerating machine that has generator refrigerant vapour regulating and antifreezing installation, comprise generator, evaporimeter, absorber, condenser, heat exchanger, solution pump, cryogenic fluid pump, control system and connect the pipeline of each parts, valve, described lithium-bromide absorption-type refrigerating machine is a direct-fired lithium bromide absorption type cold water, hot and cold water unit or steam double-effect type lithium bromide absorption cold water unit, steam single-effect type lithium bromide absorption cold water unit, hot water single-effect type lithium bromide absorption cold water unit, be characterized in: between generator and absorber or evaporimeter, be set refrigerant vapour communicating pipe, motor-driven valve was housed on communicating pipe, constitutes defroster.When motor-driven valve is opened the refrigerant vapour in the generator is imported absorber or evaporimeter by regulating the control requirement.
In lithium-bromide absorption-type refrigerating machine, by defroster is set, when the absorption pressure of unit is low excessively when causing cold water outlet temperature or water as refrigerant temperature to drop to the control limit value, start defroster, absorption pressure and evaporating pressure to unit carry out reverse adjusting control, make the cold water outlet temperature and the water as refrigerant temperature of unit stop rapidly descending and ging up, thereby reach the safe operation control purpose that under any service condition, can both prevent the icing frozen pipe of unit.
Description of drawings:
Fig. 1 is a lithium-bromide absorption-type refrigerating machine schematic diagram in the past.
Fig. 2~8 are each embodiment schematic diagram of lithium-bromide absorption-type refrigerating machine of the present invention.
Among Fig. 1, direct combustion high pressure generator 1-1, burner 2, high-temperature heat exchanger 3-1, low temperature heat exchanger 3-2, absorber feed tube 5, absorber 6, melt brilliant pipe 7, low pressure generator 1-2, condenser 9, evaporimeter 10, cold water outlet temperature sensor 11, cooling water outlet pipe 12, water as refrigerant liquid capsule 13, water as refrigerant temperature sensor 14, cryogenic fluid pump 15 and solution pump 16.
In Fig. 1~10, A steam transfer valve, B solution transfer valve, the import and export of C cold water, D cooling water outlet and inlet, E exhaust opening, F steam inlet, G coagulate water out, H hot water entrance.
The specific embodiment:
Invention one as shown in Figure 2, by direct combustion high pressure generator 1-1, burner 2, evaporimeter 10, absorber 6, low pressure generator 1-2, condenser 9, high-temperature heat exchanger 3-1, low temperature heat exchanger 3-2, solution pump 16, cryogenic fluid pump 15, melt brilliant pipe 7, control system (not shown) and connect the direct combustion high pressure generator 1-1 of the direct-fired lithium bromide absorption type cold water that pipeline, valve constituted, hot and cold water unit of each parts and absorber 6 between refrigerant vapour communicating pipe 4 is set, magnetic valve 8 was housed on communicating pipe 4.The defroster of unit is made of refrigerant vapour communicating pipe 4, magnetic valve 8 and control system (not shown).During the normal refrigerating operaton of unit, magnetic valve 8 is in normally off.When less the or cold in-water temperature of unit cooling load is low, the ability that is distributed to the absorbent solution absorption refrigerant vapour on absorber 6 heat-exchanging tube bundles is stronger relatively, the refrigerant vapour amount that sweat cooling produces in the evaporimeter causes the pressure (being called absorption pressure again) in the absorber to descend less than the pairing refrigerant vapour amount of absorber absorbability.Owing between evaporimeter and the absorber the bigger vapor stream circulation passage of area is arranged, absorption pressure decline can cause the corresponding decline of pressure (being called evaporating pressure again) in the evaporimeter, and the water as refrigerant temperature in evaporating temperature, the water as refrigerant liquid capsule 13 and the cold water outlet temperature of the unit cooling water outlet pipe 12 of flowing through descend thereupon.In case the control system of unit is by being arranged on the water as refrigerant temperature sensor 14 on the evaporimeter water as refrigerant liquid capsule 13 and being arranged on that cold water outlet temperature sensor 11 on the evaporimeter cooling water outlet pipe 12 detects the water as refrigerant temperature or cold water outlet temperature drops to the antifreeze management and control system ceiling temperature of setting (as 3 ℃ of water as refrigerant temperature, 4 ℃ of cold water outlet temperatures), and the fall off rate of water as refrigerant temperature or cold water outlet temperature surpass setting value (as 0.02 ℃/s), perhaps detect water as refrigerant temperature or cold water outlet temperature and drop to the antifreeze management and control system lower limit temperature of setting (as 2 ℃ of water as refrigerant temperature, 3 ℃ of cold water outlet temperatures), control system is promptly opened the magnetic valve 8 on refrigerant vapour communicating pipe 4, temperature and all very high refrigerant vapour of pressure enter absorber by refrigerant vapour communicating pipe in the direct combustion high pressure generator under differential pressure action, absorption pressure is raise rapidly, evaporating pressure increases, evaporating temperature, water as refrigerant temperature and cold water outlet temperature stop rapidly descending and ging up, thereby effectively prevent the danger of unit generation frozen pipe.When control system detected water as refrigerant temperature and cold water outlet temperature and all has been higher than the antifreeze management and control system ceiling temperature of setting, magnetic valve 8 cut out.
The defroster of forming magnetic valve 8 and refrigerant vapour communicating pipe 4 is arranged between the low pressure generator 1-2 of direct combustion type lithium bromide absorber cold water, hot and cold water unit and the absorber 6 (as shown in Figure 3), the control system of unit requires to open magnetic valve 8 according to operation control, the all higher refrigerant vapour of temperature and pressure enters absorber 6 by refrigerant vapour communicating pipe 4 among the low pressure generator 1-2 under differential pressure action, can effectively prevent the danger of unit generation frozen pipe equally, its control and regulation process is identical with the control and regulation process of unit shown in Figure 2.
For steam double-effect type lithium bromide absorption cold water unit shown in Figure 4, the defroster of forming magnetic valve 8 and refrigerant vapour communicating pipe 4 is arranged on the connected mode between steam high pressure generator 1-1 and the absorber 6, and the antifreeze control and regulation process of unit and direct combustion type unit shown in Figure 2 are identical.Equally, the defroster of forming magnetic valve 8 and refrigerant vapour communicating pipe 4 also can be arranged between the low pressure generator 1-2 and absorber 6 of steam double-effect type lithium bromide absorber handpiece Water Chilling Units, as Fig. 5.
Between the generator 1 and absorber 6 of steam single-effect type lithium bromide absorption cold water unit (shown in Figure 6) and hot water single-effect type lithium bromide absorption cold water unit (shown in Figure 7), be provided with the defroster of forming magnetic valve 8 and refrigerant vapour communicating pipe 4, can effectively prevent the danger of unit generation frozen pipe equally, its control and regulation process is identical with the control and regulation process of unit shown in Figure 2.
Invention two as shown in Figure 8, by direct combustion high pressure generator 1-1, burner 2, evaporimeter 10, absorber 6, low pressure generator 1-2, condenser 9, high-temperature heat exchanger 3-1, low temperature heat exchanger 3-2, solution pump 16, cryogenic fluid pump 15, melt brilliant pipe 7, control system (not shown) and connect the direct combustion high pressure generator 1-1 of the direct-fired lithium bromide absorption type cold water that pipeline, valve constituted, hot and cold water unit of each parts and evaporimeter 10 between refrigerant vapour communicating pipe 4 is set, magnetic valve 8 was housed on communicating pipe 4.The defroster of unit is made of refrigerant vapour communicating pipe 4, magnetic valve 8 and control system (not shown).When unit reasons such as less or cold in-water temperature is lower because of cooling load caused absorption pressure and evaporating pressure to descend, the water as refrigerant temperature in evaporating temperature, the water as refrigerant liquid capsule 13 and the cold water outlet temperature of the evaporimeter cooling water outlet pipe 12 of flowing through descended thereupon.In case the control system of unit detects the antifreeze management and control system ceiling temperature that water as refrigerant temperature or cold water outlet temperature drop to setting by being arranged on the water as refrigerant temperature sensor 14 on the evaporimeter water as refrigerant liquid capsule 13 and being arranged on cold water outlet temperature sensor 11 on the evaporimeter cooling water outlet pipe 12, and the fall off rate of water as refrigerant temperature or cold water outlet temperature surpasses setting value, perhaps detect the antifreeze management and control system lower limit temperature that water as refrigerant temperature or cold water outlet temperature drop to setting, control system is promptly opened the magnetic valve 8 on refrigerant vapour communicating pipe 4, temperature and all very high refrigerant vapour of pressure enter evaporimeter by refrigerant vapour communicating pipe in the direct combustion high pressure generator under differential pressure action, evaporating pressure is raise, evaporating temperature, water as refrigerant temperature and cold water outlet temperature stop rapidly descending and ging up, thereby effectively prevent the danger of unit generation frozen pipe.When control system detected water as refrigerant temperature and cold water outlet temperature and all has been higher than the antifreeze management and control system ceiling temperature of setting, magnetic valve 8 cut out.
Between the low pressure generator and evaporimeter of direct combustion type lithium bromide absorber cold water, hot and cold water unit, between the high pressure generator and evaporimeter of steam double-effect type lithium bromide absorber handpiece Water Chilling Units, same defroster (figure slightly) all can be set between steam double-effect type lithium bromide absorber handpiece Water Chilling Units low pressure generator and the evaporimeter, between the generator of steam single-effect type lithium bromide absorber handpiece Water Chilling Units and hot water single-effect type lithium bromide absorber handpiece Water Chilling Units and evaporimeter.
Invent three as shown in Figure 9, this unit has just been set up absorption pressure sensor 18 on the absorber 6 of direct-fired lithium bromide absorption type cold water shown in Figure 2, hot and cold water unit.The defroster of unit is made of refrigerant vapour communicating pipe 4, magnetic valve 8, absorption pressure sensor 18 and control system (not shown).During the normal refrigerating operaton of unit, magnetic valve is in normally off.When unit reasons such as less or cold in-water temperature is lower because of cooling load caused absorption pressure and evaporating pressure to descend, the water as refrigerant temperature in evaporating temperature, the water as refrigerant liquid capsule 13 and the cold water outlet temperature of the cooling water outlet pipe 12 of flowing through descended thereupon.In case the control system of unit detects the antifreeze management and control system upper limit pressure (as 6.58mmHg) that absorption pressure drops to setting by the absorption pressure sensor, and the absorption pressure fall off rate surpasses setting value (as 0.05mmHg/s), perhaps detect the antifreeze management and control system threshold pression (as 5.29mmHg) that absorption pressure drops to setting, control system is promptly opened the magnetic valve of refrigerant vapour on communicating pipe, the all very high refrigerant vapour of temperature, pressure enters absorber by refrigerant vapour communicating pipe in the high pressure generator under differential pressure action, absorption pressure is raise rapidly, thereby effectively prevent the danger of unit generation frozen pipe.When control system detects absorption pressure and has been higher than the antifreeze management and control system upper limit pressure of setting, closed electromagnetic valve.For guaranteeing the validity of antifreeze operation control, the absorption pressure sensor should be arranged on the low-pressure area of absorber.As be arranged on the higher-pressure region of absorber, because of the pressure of the low-pressure area of absorber is very low, can detect distortion by build-up of pressure.
Can set up absorption pressure sensor 18 equally on the absorber of Fig. 3~unit shown in Figure 8, the control system of unit comes the magnetic valve in the defroster is carried out open and close control by detecting the absorption pressure signal, thereby effectively prevents the danger of unit generation frozen pipe.
Invent four as shown in figure 10, this unit has just been set up evaporating pressure sensor 19 on the evaporimeter 10 of direct combustion unit shown in Figure 2.The defroster of unit is made of refrigerant vapour communicating pipe 4, magnetic valve 8, evaporating pressure sensor 19 and control system (not shown).During the normal refrigerating operaton of unit, magnetic valve is in normally off.When unit reasons such as less or cold in-water temperature is lower because of cooling load caused absorption pressure and evaporating pressure to descend, the water as refrigerant temperature in evaporating temperature, the water as refrigerant liquid capsule 13 and the cold water outlet temperature of the cooling water outlet pipe 12 of flowing through descended thereupon.In case the control system of unit detects the antifreeze management and control system upper limit pressure (as 6.72mmHg) that evaporating pressure drops to setting by evaporating pressure sensor 19, and the evaporating pressure fall off rate surpasses setting value (as 0.05mmHg/s), perhaps detect the antifreeze management and control system threshold pression (as 5.43mmHg) that evaporating pressure drops to setting, control system is promptly opened the magnetic valve of refrigerant vapour on communicating pipe, the all very high refrigerant vapour of temperature, pressure enters absorber by refrigerant vapour communicating pipe in the high pressure generator under differential pressure action, absorption pressure is raise rapidly, thereby effectively prevent the danger of unit generation frozen pipe.When control system detects evaporating pressure and has been higher than the antifreeze management and control system upper limit pressure of setting, closed electromagnetic valve.For guaranteeing the validity of antifreeze operation control, the evaporating pressure sensor should be arranged on the low-pressure area of evaporimeter.As be arranged on the higher-pressure region of evaporimeter, because of the pressure of the low-pressure area of evaporimeter is very low, can detect distortion by build-up of pressure.
Equally, can set up the evaporating pressure sensor on the evaporimeter of unit shown in Fig. 3~Fig. 8, the control system of unit comes the magnetic valve in the defroster is carried out open and close control by detecting the evaporating pressure signal, thereby effectively prevents the danger of unit generation frozen pipe.
Magnetic valve in Fig. 2~unit defroster shown in Figure 10 can substitute with electric control valve.