RU2366165C1 - Milk ice plant - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: invention relates to refrigerating engineering and can be used in food industry, in agroindustrial complex and farming enterprises. Milk ice plant contains reservoir with outer low-conductivity coat, gear motor, mixer and freezer built in reservoir as well as air-cooling compression-condensation refrigerating apparatus connected to the freezer by pressure and absorbing sides. Blast-heating container is a part of compression-condensation refrigerating apparatus. It is situated over the compressor. It has corkscrew tubing battery, water spherical valve and detachable plate. Compressor output hole is connected to condenser input hole through corkscrew tubing battery of blast-heating container. Water spherical valve is placed over blast-heating container.

EFFECT: invention allows to reduce operational costs and device value.

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Description

The invention relates to the field of refrigeration and can be used in the food industry, in the agricultural sector and farms serving the herd, with a daily output of 2000-6000 liters of milk.

Known milk refrigeration units for collecting, cooling and storing milk at an optimum temperature of 4 ° C [1-6], for example, milk cooling units according to patents RU No. 2265322, A01J 9/04, 2005; RU No. 2238642, A01J 9/04, 2004. According to sanitary standards, cooling should occur no more than 3 hours.

They are based on square or round bath tanks (for example, milk cooler tank according to RU patent No. 2007909, C1, A01J 9/04, 1994; milk cooler tank according to FR 2133145 A, 1998), made of stainless steel steel, with a soldered external tube evaporator (RU No. 2265322) or with a submersible tubular freon evaporator (RU No. 2238642) coming from a condensing unit. It is also possible to build tanks with built-in slotted refrigerant evaporators (for example, KRYOS tank cooler, WESTFALIA SURGE. Advertising materials. E-mail: info@/ru.westfalia.com).

Slit freon evaporators are carried out by the method of spot welding or seam-ring laser welding (KRYOS tank cooler, WESTFALIA SURGE) and directly cool the milk from the bottom of the tank, removing cold flows from the boiling freon using a gear motor and mixer, possibly also in tanks use intermediate cooling with pumps and ice water flows from the storage tank (milk cooler tank according to RU patent No. 2007909, 1994). To reduce energy consumption during storage, these tanks are surrounded on the outside with a layer of thermal insulation.

The heat generated by chilled milk at the compressor exit when compressing the boiled-off refrigerant vapors is emitted into the atmosphere by fans blowing off the condenser lamellas (see patents RU No. 2265322, RU No. 2238642), or utilized in complex large-sized double-capacitance insulated hot and of warm water fed by a water float valve with shell-and-tube condensers for water cooling (Device for cooling milk on farms (Copyright certificate for the invention, USSR, SU 1496723 AI, 1989), A shell-and-tube evaporator of a chiller with ice brine through a plate cooler cools the milk flow during milking, while warm water is used for auto-drinking and hot water for washing the udder before milking.The device is equipped with three centrifugal pumps with three pneumatic regulators to automate the control of water flows. the same option for utilization (recovery) of heat from milk into a sealed stationary storage tank of 200 l of hot water with an external plate heater with a heat exchanger up to + 52 ° C and in the germ A wall mounted storage tank (100 l of water) with an additional 2 kW heating element combined with piping and a pump supplying a vertical stationary (wall mounted) storage tank is used in KPYOS cooling tanks, UES and CVS cooling baths WESTFALIA SURGE, E-mail: info @ /en.westfalia.com), when equipping farms with the mentioned additional complex and expensive equipment.

The drawback of dairy refrigeration units (MCU) with air-cooled condensing units is the complete release of the generated heat energy into the atmosphere from the milk being cooled, despite the need for warm water on the farm: for drinking animals, washing tanks, washing the udder before milking, which is satisfied with the purchase additional sealed wall-mounted electric water heaters, and the drawback of the mentioned devices with heat recovery SU No. 1496723 and WESTFALIA SURGE equipment are additional Tel'nykh expensive and complicated plate heat exchangers, heaters, coolers, as well as pumps and piping connecting the sealed stationary wall or plate heat exchangers with drives.

The closest in technical essence to the proposed invention (prototype) is a milk refrigeration unit (MCU) according to patent RU 2265322 C1, 2005, containing a tank with an external heat-insulating coating, a gear motor, a stirrer and a copper brazed freon evaporator built into the bottom of the tank, as well as air-cooled compressor and condenser unit (KKA), connected by discharge and suction pipelines to the evaporator. For unloading milk and subsequent flushing, the MCU contains a discharge and flushing electric pump with four self-rotating vortex heads mounted on the upper sealed cover. Mechanized washing of the tank with an electric pump in the circulating mode is carried out with 300 l of water poured from the water supply, however, for better washing carried out by warm water, farmers are forced to additionally purchase wall-mounted sealed water heaters (boilers) with heating elements and heat stabilizers with a power of 2 ... 3 kW, at a price of 12000 ... 15000 rubles, with a capacity of 100 ... 150 l, adding 50 ... 80 l of hot water + 70 ° C when flushing in circulation mode.

The main disadvantage of the prototype is the "blowing" of the thermal energy of the condensed vapors of freon obtained by cooling the milk into the atmosphere through air-cooled condensers. This leads to the need for additional initial costs for electric boilers for high-quality washing with hot water, as well as to the consumption of additional electricity of the order of 20 ... 30 kWh per day.

The invention is aimed at reducing the operational energy consumption, complexity and cost of MCA by utilizing the heat generated by the compression of the refrigerant vapor in 300 liters of hot water used on farms for washing tanks and other domestic needs, while maintaining ease of implementation and compact design without additional pumps , plate shell and tube heat exchangers.

The specified technical result is achieved by the fact that in a milk refrigeration unit containing a tank with an external heat-insulating coating, a gear motor, an agitator and an evaporator integrated in the tank, as well as an air-cooled compressor-condensing unit (KKA) connected by discharge and suction pipelines to the evaporator, ACCORDING TO THE INVENTION, a recuperator tank located above the compressor, with a screw tubular coil, a water float valve and a removable cover, is introduced into the CCA. compressors connected through a helical tubular coil heat exchanger tank to the inlet of the condenser, and the water supply float valve is placed at the top of the heat exchanger tank.

The invention is illustrated by drawings.

Figure 1 presents a drawing of a General view of a milk refrigeration unit, figure 2 is a schematic combined circuit diagram, figure 3 is a longitudinal section of a tank-recuperator.

Milk refrigeration unit (figure 1, 2) contains a tank 1 with removable covers 2 and an external heat-insulating coating 3, a gear motor 4, an agitator 5 and an evaporator 6 built into the bottom of the tank. The built-in evaporator 6 can be made with a slotted or copper soldered outside to the bottom of the tank 1. The MCA also includes a compressor condenser unit KKA 7 with a compressor 8 connected in series, a screw tubular coil 9 of the recovery tank 10, an air-cooled condenser 11, a receiver 12, a filter 13, which is thermoregulated in a ventilator (ТРВ) 14. ККА 7 is connected to the built-in evaporator 6 of the tank 1 by the pipelines of discharge 15 and suction 16.

The recuperator tank 10 (Figs. 1, 3) is located in the general frame 17 of the control unit 7 above the compressor 8 at a level of 800 mm from the base and contains a removable cover 18. At the bottom of the recuperator tank 10 there is a screw tubular coil 9 made of stainless steel pipe ⌀ 20 mm × 1 with a length of 6 running meters, wound ⌀500 mm in increments of 70 mm, fixed by welding from the inside of the recovery tank 10 on the uprights 19. The coil 9 is located in the lower part of the recovery tank 10 to be constantly immersed in water. At the top of the recovery tank 10, a plumbing float valve 20 is placed at a level of 1700 mm from the floor. The 300 L recuperator tank is a cylindrical welded structure with a height of 1000 mm and a diameter of 630 mm. The water float valve 20 is installed at a level of 900 mm from the bottom of the recuperator tank 10. A drain ball valve 21 of hot water from the tank of the recuperator 10 is installed at a level of 70 mm from the bottom of the recuperator tank 10. The water supply pipe 22 is connected to the water float valve 20 and also contains ball valve 23 for cold water, designed for domestic use, in particular for refueling a car drinker and washing a tank 1. The MCU also includes a thermostat (not shown in Figs. 1, 2, 3), which de-energizes KKA 7 when milk is cooled to + 4 ° FROM.

The Moscow Art Theater works as follows.

When filling the tank 1 with warm milk + 35 ° С for about 500 l, KKA 7 is turned on and the compressor 8 draws in 16 pipelines of the freon formed during its boiling in the evaporator 6, which is built into the bottom of the tank 1. Saturated refrigerant vapors with a pressure of 4 ... 4.5 at and at a temperature of 10 ... 15 ° C, the compressor 8 is compressed to a pressure of 15 ... 18 at at a temperature of 80 ... 90 ° C and enters the screw-shaped coil-coil 9 of the recovery tank 10. The recovery tank 10 is filled with 280 l through the water float valve 20 tap water 12 ... 17 ° C, due to which pressure and eratura compressed vapor refrigerant flowing through the pipe coil 9 in the air-cooled condenser 11 is reduced by 10 ... 15 ° C and for 2 ... 2.5 atm to 14 atm and 16 ... 70 ... 80 ° C. The contact area of the coil pipe 9 with the water of the recovery tank 10, which is 0.4 m ² , with a thermal pressure (temperature difference between the freon and water vapor) of about 60 ° C, removes up to 3 kW power from the circulating freon vapor, which corresponds to 15 ... 20 % installed capacity of the air-cooled condenser 11. This power up to 3 kW, on the one hand, reduces the peak load on the compressor 8 in comparison with the prototype by 2 ... 2.5 at and 10 ... 15 ° C, thereby contributing to an increase in the MHC resource and its more reliable operation, and on the other side, provides automatic heating of the water in the recovery tank 10, which is subsequently used for domestic purposes. Natural thermal convection of water in the recovery tank 10 uniformly warms up all 280 l and does not require an additional mixer. In the 2 hours necessary to cool the milk in half the volume of the tank (1000 liters for two-ton and four liters for four-ton), the recovery tank 10 is gradually heated to 70 ° C. The heating power of the tubular coil 9 decreases from 3 kW to hundreds of watts as the heat pressure decreases. In this case, the maximum capacity of the order of 3 kW, the recovery tank 10 takes away from the compressor 8 in the first 0.5 hours of operation. During this time, the temperature of the recovery tank 10 rises to 45 ... 50 ° C. From the theory of refrigeration machines it is known that the maximum load on the compressor 8 and KKA 7 occurs at the initial stage of milk cooling at + 35 ° C. As the milk cools to + 4 ° C, the vapor pressure at the suction in the pipe 16 decreases by about half to 2.5 atm, and their temperature decreases to -5 ° C. Accordingly, the pressure of the discharge vapors of the compressor 8 decreases to 14 atm, the vapor temperature decreases to 70 ° C. The thermal pressure in the tubular coil 9 decreases tens of times and the temperature stabilizes in the heat recovery tank 10. With further passage of the compressed refrigerant vapor from the outlet of the tubular coil 9 through the air-cooled condenser 11, their temperature decreases to 35 ... 40 ° C due to blowing of the fan , and the vapor condenses into the liquid fraction, collecting in the receiver 12.

At a pressure of 14 atm, the liquid refrigerant passes through a filter drier 13 in the expansion valve 14 and is then injected through the discharge pipe 15 into an evaporator 6 built into the tank 1, where it boils at the mentioned low pressure from contact with warm milk. Due to the feedback, the expansion valve ТРВ 14 automatically reduces the supply of liquid refrigerant as the milk cools, providing maximum cooling capacity and the load of the MCU at the initial stage at a temperature of + 35 ° С.

The gear motor 4 with a stirrer 5 ensure uniform mixing of milk and removal of all refrigeration power from the built-in evaporator 6. Next, the evaporated freon cyclically enters the suction pipe 16.

When the milk is cooled to + 4 ° C, the thermostat is activated (not shown in Figs. 1, 2, 3) and deenergizes KKA 7. The MCU switches to the storage of chilled milk with homogenization (stirring) using a gear motor 4 and a mixer 5.

Thus, after the completion of the cooling process of milk in the recovery tank 10, 280 l of warm water is formed, heated to 70 ° C. The main heating power of the order of 2 ... 3 kW enters the recuperator tank 10 at the initial stage with a peak load of the MCU in the first 0.5 hours of operation. This power reduces the maximum load at the compressor output by 2 ... 2.5 atm (by 15%) compared with the prototype and thereby increases its service life.

At the same time, this heat flow heats 280 liters of water in the recovery tank 10 to 70 ° C. The level of warm water in the recovery tank 10 is 1700 mm above the base of the KKA 7, which makes it possible to use it by gravity when opening the drain ball valve 21 for domestic needs and heating the tap water entering through the valve 23 to the following consumers: a) an automatic watering machine (the water level is not exceeds 400 mm), b) mechanized washing of the tank 1 with warm water in the circulation mode when the circulation pump is turned on (the water level in the tank 1 during circulation does not exceed 400 mm, the volume is 300 l, c) the automatic washing machine closed x tanks, for example, of the type KRYOS WESTFALIA SURGE: the water level during cyclic washing in the tank does not exceed 400 mm, the volume is 200 l, including 70 l of hot water in each of their three cycles - rinse, alkaline and acid, g) wash the udder before milking.

As the consumption of hot water for domestic needs from the drain valve 21, the recovery tank 10 is replenished through the float valve 20 with tap water and its temperature drops from 70 ° C to 20 ° C. In the absence of consumption, the 280 l recovery tank for 10 ... 12 hours is gradually cooled by ambient air to 25 ... 30 ° C, being prepared for the next cycle of two-milking (three-milking) cooling to consume the next recuperation power of 2 ... 3 kW with a thermal pressure in the tubular screw coil 9 of the order of 40 ... 50 ° C.

Thus, in comparison with the prototype, the consumer has a direct material benefit, because free from the need to buy an additional 2 kW electric boiler with a capacity of 150 liters at a cost of 15,000 rubles. The cost of the recovery tank 10 with short connecting pipelines does not exceed 7,000 rubles, the selling price of 10,000 rubles. The daily electricity consumption was reduced by 10 kWh. Another advantage of the proposed MCA compared with the prototype is to reduce the peak load on the compressor during cooling milk at an ambient temperature of 35 ° C during the summer heat. In the first half hour of the MCU operation, the recuperator tank heats up to 45 ... 50 ° C, the heat pressure in the tubular coil 9 decreases, the power removed by the recuperator drops and the pressure on the compressor rises. To effectively reduce the pressure in the compressor 8 until the milk is completely cooled, the ball valve 21 during the summer heat is opened at a cost of 5 ... 10 l / min, draining warm water to consumers with a volume of 300 ... 600 l / h. Drain of warm water 30 ... 35 ° C during the operation of KKA 7 is accompanied by automatic recharge of the recovery tank 10 through the water float valve 20 with cold water. Therefore, the heat pressure in the tubular coil 9 is maintained all the time the milk is cooled and adequate protection against compressor overloads 8 is provided.

Compared to WESTFALIA SURGE analogues, which use separate assembly units for heat recovery of sealed stationary or wall-mounted drives with plate heat exchangers and corresponding pumps, the arrangement of an open heat recovery tank 10 with a cover 18, a water float valve 20, and a tubular coil 9 above compressor 8 KKA 7 allows to a minimum (about 1 m) reduce the connecting pipelines between the compressor 8, the recovery tank 10 and the condenser 11, and also simplify and reduce the cost of the structure to the utmost.

The specified technical solution in 2007 was introduced into serial production at the enterprise NPP Avtomash LLC (Kovrov).

Information sources

1. Milk refrigeration unit. Patent RU No. 2265322, A01J 9/04, F25D 1/00, F25D 17/06, 2005.

2. Milk cooling unit. Patent RU No. 2238642, A01J 9/04, 2004

3. The milk cooler tank. Patent RU No. 2007909, A01J 9/04, 02/28/1994

4. Milk cooler. Patent FR 2133145 A, 02/11/1998

5. A device for cooling milk on farms. Certificate of invention, USSR, SU 1496723 A1, 07/30/1989

6. Tank cooler KRYOS and bath coolers UES and CVS. WESTFALIA SURGE. Promotional materials. LLC Westphalia-Serge. 105005, Moscow, Pleshkovsky per. 6, p. 2. Email: info@ru.westfalia.com.

Claims (1)

A milk refrigeration unit containing a tank with an external heat-insulating coating, a gear motor, an agitator and an evaporator integrated in the tank, as well as an air-cooled compressor-condensing unit (KKA) connected by discharge and suction pipelines with an evaporator, characterized in that a recovery tank located above the compressor with a screw-shaped tubular coil, a water float valve and a removable cover, the compressor outlet being connected through a screw-shaped tubular th coil heat exchanger tank to the inlet of the condenser, and the water float valve is placed at the top of the tank-heat exchanger.

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