CN1434261A - Refrigeration technology used under ultralow evaportion temp. work condition - Google Patents

Abstract

The refrigeration technique under the condition of ultralow evaporation temp. includes four techniques: twice restriction, mid-pressure compensation, centrifugal oil separation and multieffect mixing. Said twice restriction technique is characterized by making the high-pressure liquid undergo the process of first restriction treatment in middle cooling device, reducing the high pressure liquid into middle-pressure one, then making secondary restriction; the middle-pressure compensation technique is to compensate other system load, for high-temp. storehouse, to high-pressure level under the condition of conformble pressure, the centrifugal oil separation technique adopts "centrifugal oil separation" type low-pressure circulating barrel, and connects an oil-collecting device in its botton portion for collecting settled pure ammonia liquor.

Description

A kind of Refrigeration Technique that is used under the ultralow evaporating temperature operating mode

Technical field

What the present invention relates to is a kind of to the freezing processing of food and fresh-keeping ultralow evaporating temperature New Refrigerating technology, belongs to refrigeration Technique of Speed Freezing field.

Background technology

At present to the freezing processing and fresh-keeping main employing " quick-frozen " technology of food, what select for use is the quick-frozen of freezing of new screw unit, however its equipment price costliness, be home equipment 3-10 doubly.Also have many freezing enterprises to adopt " freezing slowly " technology, yet that " freezing slowly " technology can make food pass through the speed in ice crystal district in process is slower, crystal ice granule increases, and food cell is damaged, and the back dehydration of thawing is serious, and invertibity is poor.Adopt the quick-frozen of homemade piston refrigeration compressibility refrigeration, its refrigeration process still belongs to normal more than evaporating temperature-35 ℃, but when entering the best quick freezing temperature zone-evaporating temperature-35 of food ℃～-50 ℃, the loss of throttling shwoot then occurs and increase 50%, refrigerating amount attenuation 45%, energy consumption rising 30～50% waits problems such as the pernicious drift of each big performance indications.

Summary of the invention

The objective of the invention is to the defective at above-mentioned existence, propose a kind of ultralow evaporating temperature New Refrigerating technology, it can effectively overcome the problems of the prior art.Technical solution of the present invention: divide second throttle, the compensation of middle pressure, centrifugal branch oil, multiple-effect to mix four technology, wherein the second throttle technology is that throttling is once in intercooler with highly pressurised liquid, and highly pressurised liquid reduced to middle pressure, then enter the circulation liquid receiver again and carry out the throttling second time, the pressure reduction of this moment is the pressure reduction of middle pressure and evaporating pressure; In press compensation technique be with other system loading such as high temperature storehouse under the situation that pressure conforms to, add to hiigh pressure stage, make hiigh pressure stage form the multiple-effect operating mode; Centrifugal minute oil tech is to adopt " centrifugal branch oil " formula low pressure recycle bucket, it connects an oil catcher in low pressure recycle bucket bottom, a drain pipe is set in tube connector, with this pipe is suitable for reading put in barrel at the bottom of 50cm, pure ammoniacal liquor behind the collecting precipitation is supplied with ammonia pump, drain pipe external diameter and oil catcher tube connector internal diameter have big gap, can hold the oil circulation, during work, because fluid mouth of pipe imbibition, cause the liquid in bucket rotation,, under the effect of rotary centrifugal force, be pushed to circulation bucket inwall because the proportion of oil is big than ammoniacal liquor, and then along the downslide of bucket wall, enter oil catcher through oil collecting pipe, in service as long as show that according to the liquid level on the oil catcher meter observes pasta to when the oil catcher top 70%, can under not stopping production situation, oil be discharged; The multiple-effect hybrid technology is when the compressor cooling quick-freezing plant is just lowered the temperature, use single stage compress, it can play the effect of the big refrigerating capacity of low energy consumption, when quick-freezing plant normally moves, increase the inspiratory capacity of low-pressure stage, it not only can increase refrigerating capacity, simultaneously can be to the charge air cooler ftercompction, each unit is scientifically made up, form the multiple-effect hybrid system.Its concrete way is:

A. single level machine 4AV12.5 all adopts the double loop, be that head is established-15 ℃ and-50 ℃ two and packed into steam discharge, so where necessary, single level machine not only can independently be born the interior refrigerant compression of evaporation scope more than-15 ℃, and the low-pressure stage that can be used as-50 ℃ of quick-frozen systems participates in operation, press compensation in the execution, when single-stage car conduct-50 ℃ low-pressure stage is moved, its gland steam exhauster is provided with a bypass pipe and is communicated with-15 ℃ of steam inlet pipes, the two pressure is approximate, and with this valve open ,-50 ℃ exhaust is mixed into charge air cooler with-15 ℃ air inlet, further centering is compressed into row compensation 0.25mpa, compresses into load carrying in this moment;

B. cold excessively in the temperature that requires pre-cold water, or require high temperature storehouse alternating temperature to be lower than 0 ℃, use the twin-stage machine, it can bear the cold in-50 ℃～-15 ℃ scopes;

C. design high pressure back suction device, promptly on the intake and exhaust house steward, establish a bypass pipe, adjusting by valve in case of necessity, former exhaust is become air inlet, the gas that sucks back is discharged to former low pressure air suction part, the ammonia of any high-pressure section is evacuated to low-pressure section stores, the waste that will let out ammonia when promptly not causing high in the past maintenance, when making system maintenance again and accident comparatively safe when speedily carrying out rescue work.

D. design " frost " remover replenishes suction vapour heat with hot ammonia quickly and effectively and gets rid of.

Advantage of the present invention: during evaporating temperature-50 ℃, thermodynamic perfect degree is more than 0.75; Combination property is compared with traditional handicraft, and restriction loss reduces 50%, and energy consumption reduces by 30%, and cold improves 15～30%, and operational safety performance improves 100%, and installed capacity reduces by 30%.Investment cost is 1/10～1/20 of an import equipment.

Four technology of this patent are used on the fast food freezing production line its process of refrigerastion:

By the two-phase flow working medium that evaporator evaporation refrigeration produces, the low pressure recycle bucket＜oily formula of centrifugal branch that enters high-temperature systems (15 ℃) and cryogenic system (50 ℃) respectively〉in carry out gas, liquid, oily separating.Isolated oil is discharged system through oil catcher; Isolated liquid freezes through ammonia pump blowback evaporator evaporation again; Gas by-pass after the separation is to single-stage and double-stage compressor boil down to gases at high pressure.

Single-stage compressor exhaust by-pass, wherein one the road to the charge air cooler ftercompction, and another road enters condenser after oil eliminator divides oil;

The double-stage compressor low-pressure stage is vented to charge air cooler, with the exhaust of single level machine or high-temperature systems circulation bucket give vent to anger mixes the back form in pressure zone load, again by the air-breathing compression of hiigh pressure stage after oil eliminator enters condenser after dividing oil.Condenser is condensed into liquid with high pressure gas and is stored in the high pressure receiver.

The highly pressurised liquid of high pressure receiver is divided into two-way before charge air cooler under differential pressure action: once be throttled to the additional feed flow of high-temperature systems circulation bucket after a path charge air cooler cooling coil equipressure is cold excessively; Entering the charge air cooler step-down after the throttling in another road is to arrive low temperature circulation bucket second throttle after the middle pressure again to replenish feed flow.The feed flow that is replenished is sent to the evaporimeter circularly cooling through ammonia pump.

Claims (2)

1, a kind of Refrigeration Technique that is used under the ultralow evaporating temperature operating mode, it is characterized in that branch second throttle, the compensation of middle pressure, centrifugal branch oil, four technology of multiple-effect mixing, wherein the second throttle technology is that throttling is once in intercooler with highly pressurised liquid, and highly pressurised liquid reduced to middle pressure, then enter the circulation liquid receiver again and carry out the throttling second time, the pressure reduction of this moment is the pressure reduction of middle pressure and evaporating pressure; In press compensation technique be with other system loading such as high temperature storehouse under the situation that pressure conforms to, add to hiigh pressure stage, make hiigh pressure stage form the multiple-effect operating mode; Centrifugal minute oil tech is to adopt " centrifugal branch oil " formula low pressure recycle bucket, it connects an oil catcher in low pressure recycle bucket bottom, a drain pipe is set in tube connector, with this pipe is suitable for reading put in barrel at the bottom of 50cm, pure ammoniacal liquor behind the collecting precipitation is supplied with ammonia pump, drain pipe external diameter and oil catcher tube connector internal diameter have big gap, can hold the oil circulation, during work, because fluid mouth of pipe imbibition, cause the liquid in bucket rotation,, under the effect of rotary centrifugal force, be pushed to circulation bucket inwall because the proportion of oil is big than ammoniacal liquor, and then along the downslide of bucket wall, enter oil catcher through oil collecting pipe, in service as long as observe pasta to from oil catcher top 70% according to the demonstration of the liquid level on oil catcher meter, can under not stopping production situation, oil be discharged; The multiple-effect hybrid technology is when the compressor cooling quick-freezing plant is just lowered the temperature, use single stage compress, it can play the effect of the big refrigerating capacity of low energy consumption, when quick-freezing plant normally moves, increase the inspiratory capacity of low-pressure stage, it not only can increase refrigerating capacity, simultaneously can be to the charge air cooler ftercompction, each unit is scientifically made up, form the multiple-effect hybrid system.

2, a kind of Refrigeration Technique that is used under the ultralow evaporating temperature operating mode according to claim 1, the concrete way that it is characterized in that the multiple-effect hybrid technology is: a single level machine 4AV12.5 all adopts the double loop, be that head is established-15 ℃ and-50 ℃ two and packed into steam discharge, so where necessary, single level machine not only can independently be born the interior refrigerant compression of evaporation scope more than-15 ℃, and the low-pressure stage that can be used as-50 ℃ of quick-frozen systems participates in operation, press compensation in the execution, when single-stage car conduct-50 ℃ low-pressure stage is moved, its gland steam exhauster is provided with a bypass pipe and is communicated with-15 ℃ of steam inlet pipes, the two pressure is approximate, with this valve open,-50 ℃ steam discharge is mixed into charge air cooler with-15 ℃ admission, and further centering is compressed into row compensation 0.25mpa, pressure zone load operation in this moment; B is cold excessively in the temperature that requires pre-cold water, or requires high temperature storehouse alternating temperature to be lower than 0 ℃, uses the twin-stage machine, and it can bear the cold in-50 ℃～-15 ℃ scopes; C design high pressure back suction device, promptly on the intake and exhaust house steward, establish a bypass pipe, adjusting by valve in case of necessity, former exhaust is become air inlet, the gas that sucks back is discharged to former low pressure air suction part, the ammonia of any high-pressure section is evacuated to low-pressure section stores, the waste that will let out ammonia when promptly not causing high in the past maintenance, when making system maintenance again and accident comparatively safe when speedily carrying out rescue work; D design " frost " remover replenishes suction vapour heat with hot ammonia quickly and effectively and gets rid of.