Automatic pasteurizing and cooling plant. Pasteurization cooling plant Pasteurization cooling plant for milk

Plate pasteurization - cooling unit for fermented milk products is designed for pasteurization and cooling of dairy products in a continuous thin-layer closed flow with automatic control and regulation of the technological process in the production of fermented milk products.

Device.

Plate pasteurization and cooling plant for fermented milk products consists of a plate heat exchanger, hot water preparation systems (convection tank, hot water pump, injector) for pasteurization of the product and heating the product to the fermentation temperature, a pump for the product, a control panel, a holder, a control system and automatic control of the technological process of processing the product, pipelines, valves mounted on the frame. The unit is compact and has a modular design with high installation readiness. The unit retainer is a stand-alone module, which can be mounted in any place relative to the unit during installation of the unit.

Operations performed:

Milk heating up to the separation temperature of 55-60 °C;

Heating milk to a homogenization temperature of 75-80 ° C;

Milk heating up to the pasteurization temperature of 90-95 °C;

Exposure of the product at a pasteurization temperature of 300 seconds;

Cooling the product to a fermentation temperature of 20-50 ° C.

2.3. Plate heat exchanger (heat exchanger)

Purpose:

The plate heat exchanger is designed to cool or heat milk, cream, kefir, beer, wine, juices, drinks, alkali, water, vegetable oil, melange and other liquid products in a closed flow.

Due to their thermal efficiency, plate heat exchangers are characterized by a high level of compactness. Heating or cooling installations arranged on their basis have significantly smaller dimensions than installations of similar purpose of other types, the efficiency of all is more than 90%. Parts of heat exchangers that come into contact with products are made of materials approved for use in the food industry. Depending on the chemical and physical properties of the products, as well as thermal conditions (temperature, pressure), heat exchangers are equipped with seals made of appropriate materials (food grade rubber, silicone, fluoroplastic, etc.). Heating and cooling devices allow for closed circulation washing under pressure, easy to operate and repair.

 The coolant is water or brine.

 The heat carrier is water, steam.

 The heat exchanger consists of heat exchanger plates, a frame and a pressure plate, tied together with studs.

 Heat transfer plates are produced in different types, differing: in the type of seals that ensure the tightness of the apparatus, in geometric dimensions.

Type A Mortgage seal - securing the seal to the plate using clip-on clamps (PBK-1, PMK-1).

Type B Fastening seals to the plate using adhesive bonding (PM-1).

Table 10 Technical characteristics of plate heat exchangers

	PBK-1	PMK-1
Productivity, l/hour:
Temperature difference between the outgoing product and the coolant (heat carrier): 2-4°C (with a 1/3 ratio)
Overall dimensions of the device, mm:
 Height:
 Width:
Plate material	stainless steel 12X18H10T
Plate thickness, mm
Maximum operating temperature, °С
Maximum working pressure, MPa
Plate dimensions (length x width x thickness)
Heat exchange surface, dm2
Flow area, DN
Connecting thread diameter

In an automated plate-type pasteurization-cooling plant (Fig. 22), the working process proceeds in the following order.

Rice. 22. Scheme of an automated plate pasteurization and cooling plant:

1 - lamellar apparatus; 2- separator-milk cleaner; 3- centrifugal pump; 4- surge tank; 5-bypass valve; 6- survive; 7- hot water pump; 8- boiler; 9- injector; 10- control panel; I-section of the first regeneration; II - section of the second regeneration; III - pasteurization section; IV - section of water cooling; V- section of brine cooling.

From the milk collector, milk is fed by gravity or with the help of a pump into the surge tank 4. The milk level must be at least 300 mm to prevent air from being sucked into the milk pump. Milk is supplied by pump 3 to section I of the plate apparatus (regeneration section), where it is heated by heat exchange with hot milk coming from the pasteurization section through holder 6. The milk heated to 37 ... 40 ° C leaves the section to the milk purifier, and from there is fed into the second regeneration section, where it is additionally heated with pasteurized milk, which has previously undergone heat exchange in regeneration section I. From regeneration section II, milk passes into pasteurization section III, where, due to heat exchange with hot water, it is heated to a temperature of 76 ° C ..

The pasteurized milk passes through the holder in the I and II sections of the regeneration, where it gives off part of the heat to the cold milk and its temperature drops to 20...25°C. Further, this milk passes successively sections of the cooler, after which its temperature drops to 5...8°C, depending on the initial temperature of the cooling water or brine. Cold milk goes to tanks for storage. The holder in the installation is designed to enhance the pasteurization effect. An additional exposure for 20 s in a holder before cooling contributes to the destruction of the microflora of milk. Hot water for pasteurization is prepared in a boiler. It is heated by steam entering the hot water circulation system through the injector 9 of the steam line of the boiler plant.

The electro-hydraulic valve on the steam line provides automatic adjustment of the steam supply depending on the temperature of the milk. When the temperature of the milk leaving the pasteurization section drops, the bypass valve 5 automatically directs the milk to the surge tank for re-pasteurization.

The installation has a control panel (Fig. 6), equipped with instrument panels with equipment and instruments located on them. Instruments and control keys are placed on the control panel shield. Electronic bridge 2 is designed to record the milk pasteurization temperature, control the milk bypass valve, light and sound alarms of the unit. The electronic regulator 7 controls the steam supply valve. Logometer 5 controls the milk cooling temperature. The setpoint 10 is used to set the pasteurization temperature. Switch 11 switches the control system to automatic mode or to manual control. With manual (remote) control, the control valve is operated by a key. Toggle switch 6 controls the operation of the bypass valve, switch 12 controls the operation of the engine, toggle switch 8 controls the sound alarm. Lamps 3 signal the inclusion of the remote control, motors and a decrease in the pasteurization temperature. The remote control is connected to the mains through a batch switch 9.

Before starting the installation, check the distance of the package of plates of the apparatus and bring their compression to zero along the pressure device. They control the connections, the direction of rotation of the separator drum and the pump rotors. Soda solution is poured into the surge tank and the pumps are turned on. Turn on steam. After 15 minutes, the flushing is stopped and cold water is supplied to the system to displace the soda solution. Rinse the system in circulation mode with hot water for 30 minutes, counting from the moment clean water leaves the apparatus at a temperature of 85°C.

Before sterilization, the switch of the remote control is set to the appropriate positions "Steril." and "Automatic". At the end of sterilization, water is displaced from the apparatus with milk and pasteurization is continued, setting all control panel devices to automatic mode. The white lamp on the unit's control panel indicating milk return must go out.

After switching the devices to automatic control mode, first turn on the supply of milk from the milk tank or tank to the surge tank, and then the pump to supply milk to the pasteurizer. By this time, the separator drum must have reached the operating speed, otherwise it may overflow. At the same time turn on the hot water pump. With this start-up order, milk from the surge tank displaces water from the apparatus after sterilization. It is drained into the sewer until milk appears, then the hose is attached to the milk tank.

At the beginning of the installation, the milk does not have time to heat up to the pasteurization temperature and returns to the surge tank. When the temperature rises to the set value, the cold water supply is turned on. After the bypass valve is activated, the milk is sent to the holder, and the device switches to work according to the specified technological scheme in automatic mode. The continuity of the installation is limited by the volume of the dirt space of the separator drum and is 2.5 ... 3 hours, depending on the contamination of milk with mechanical impurities.

When the machine stops, the supply of milk to the surge tank is stopped and immediately after it is emptied, the water supply is turned on to displace milk residues. When water appears, the hose is directed to the sewer, the steam supply is stopped, the hot and cold floor pumps and the milk pump are turned off, and the milk purifier of the installation is stopped.

Pasteurization of milk and dairy products has become widespread in all countries of the world. It allows you to significantly increase the shelf life and sale of products.

Milk and dairy products are pasteurized in special containers, tubular pasteurization units, as well as in plate pasteurization and cooling units.

Tubular pasteurization plant

The tubular pasteurization plant consists of two centrifugal pumps, a tubular apparatus, a non-return valve, steam traps and a control panel with process control and regulation devices.

The main element of the installation is a two-cylinder heat exchanger, consisting of the upper and lower cylinders, interconnected by pipelines. Tube sheets are welded into the ends of the cylinders, in which 24 pipes with a diameter of 30 mm are expanded. Stainless steel tube sheets have short cut channels connecting successively the ends of the pipes, thus forming a continuous coil with a total length of about 30 m. The end cylinders are covered with covers with rubber seals to ensure the tightness of the apparatus and isolate the short channels from each other.

Steam is supplied to the annulus of each cylinder. The exhaust steam in the form of condensate is discharged using thermodynamic steam traps.

Heated milk moves in the inner tube space, passing successively the lower and upper cylinders. A control valve for steam supply is installed at the steam inlet, and a return valve is installed at the milk outlet from the machine, with the help of which underpasteurized milk is automatically sent for re-pasteurization. The return valve is connected through a temperature controller with a temperature sensor located also at the milk outlet from the machine. The unit is equipped with pressure gauges to control the pressure of steam and milk.

The processed product is fed from the storage tank with the help of the first centrifugal pump to the lower cylinder of the heat exchanger, where it is heated by steam to a temperature of 50-60°C and passes into the upper cylinder. Here it is pasteurized at a temperature of 80-90°C.

The second pump is designed to supply milk from the first cylinder to the second. It should be noted that in tubular pasteurization plants, the speed of movement of various products is not the same. In the installation for pasteurization of cream, the speed of their movement in the pipes of the heat exchanger is 1.2 m/s. In the process of heat exchange, the cream enters the pasteurizer cylinders with the help of a single centrifugal pump. The speed of milk movement due to the use of two pumps is higher and amounts to 2.4 m/s.

The advantages of tubular pasteurization plants in comparison with lamellar ones are a significantly smaller number and dimensions of sealing gaskets, and the disadvantages are large dimensions and high metal consumption; in addition, when cleaning and washing these installations, free space is required on the side of the ends of the cylinders of the heat exchanger.

Tubular installations are effective if the subsequent milk processing process is carried out at a temperature slightly different from the pasteurization temperature.

Plate pasteurization and cooling plant

Plate and pasteurization-cooling units are used for the heat treatment of milk, cream and ice cream mixtures. The design of each of these installations has its own characteristics, which are reflected in the description of equipment for the production of various dairy products.

The composition of the plate pasteurization and cooling unit used for heat treatment of milk, includes an equalizing tank, centrifugal pumps for hot water and milk, a plate apparatus, a milk separator, a holding tank, a non-return valve, a heating system and a control cabinet.

The centrifugal pump is designed to take milk from the surge tank and supply it to the lamellar apparatus. To exclude air infiltration into the pump, a certain level of milk (at least 300 mm) is maintained in the surge tank using a float mechanism. Failure to comply with this condition leads to foaming, which reduces the effectiveness of pasteurization.

The plate pasteurizing and cooling unit has a main front rack and an auxiliary rear rack, in which the ends of the upper and lower horizontal rods are fixed. The upper one is intended for suspension of heat exchange plates. Along the periphery of each plate, a large rubber gasket is placed in a special groove, which hermetically seals the channel.

The plates have holes with small annular rubber gaskets. After assembling the plates, two isolated systems of channels are formed in the apparatus, through which milk and coolant move.

The lamellar apparatus is equipped with stainless steel heat-exchange plates divided into five sections: the first and second stages of regeneration, pasteurization, artesian water cooling and ice water cooling. Some plate machines have one regeneration section. The sections are separated from each other by special intermediate plates, which have fittings at the corners for supplying and discharging liquids. Serial numbers are stamped on the plate, the same numbers are indicated on the plate layout diagram.

The plates are pressed against the rack using a plate and clamping devices. The degree of compression of the thermal sections is determined according to the table with a scale installed on the upper and lower struts. Zero division is set along the axis of the vertical strut bolt, it corresponds to the minimum compression that ensures tightness.

In installations of high productivity, lamellar apparatuses have two-sided arrangement of sections in relation to the main rack.

The composition of the pasteurization-cooling plant also includes milk separator and a sustainer. milk purifier serves to purify milk. When using a cleaner with a centrifugal sludge discharge, one separator is installed, with a manual one - two.

The holder is one of the main elements of pasteurizing and cooling installations. In it, milk is kept at the pasteurization temperature for a certain time (20 or 300 s) necessary to complete the bactericidal action of the temperature.

The holder consists of one or four cylinders, which are fixed on tubular supports. In some installations, the holder is made in the form of four spiral sections made of pipes with a diameter of 60 mm.

The return, or bypass, electro-hydraulic valve serves to automatically switch the milk flow to re-pasteurization when its temperature in the pasteurization section decreases.

The work of the pasteurization-cooling plant in the production of drinking milk is as follows. Milk from the storage tank is sent by gravity or under pressure to the surge tank, from where it is pumped to the first regeneration section of the lamellar apparatus. Heated to 37-40°C, it enters the milk purifier for removal of mechanical impurities and goes for further heating to the second regeneration section and the pasteurization section, where it is heated to 90°C. From the pasteurization section, milk is sent through an electro-hydraulic bypass valve to the holding valve, stays there for up to 300 s, then enters the regeneration section to transfer heat to the oncoming flow of milk entering the apparatus. After that, it enters successively into the water and brine cooling sections, where it is cooled to 8°C, and leaves the plant.

Milk is cooled using artesian and ice water or brine coming from the refrigeration unit. Cooling of milk to a temperature not exceeding 8°C is possible only with the normal frequency of water and brine supply in the cooling section. The whole pasteurization process is controlled automatically.

The required pasteurization temperature is maintained by an electronic bridge. Smooth adjustment. The pasteurization temperature is recorded on the chart tape of the control device. Sound and light alarms are triggered when the pasteurization temperature drops below set parameters.

To heat the product, in addition to hot water, steam or electricity, in some pasteurization and cooling plants, infrared heaters are used as a source of direct heating of milk. In installations with a small capacity, milk is fed to the processing of an infrared emitter in a thin layer.

Plate pasteurization-cooling units have a number of advantages compared to other types of thermal devices:

• low working capacity, which allows automation devices to more accurately track the progress of the technological process (in a lamellar plant, the working capacity is three times less than in a tubular unit of the same capacity);
• the ability to work efficiently enough with a minimum thermal pressure; minimal heat gain and loss of heat and cold (thermal insulation is usually not required);
• significant savings (80 ... 90%) of heat in the regeneration sections (specific steam consumption in plate-type installations is 2-3 times less than in tubular ones, and 4-5 times less than in capacitive heat exchangers);
• small installation area (plate installation occupies about 4 times less surface than a tubular installation of the same capacity);
• the ability to change the number of plates in each section, which allows you to adapt the heat exchanger to a specific technological process;
• Possibility of in-place circulation washing of equipment.

One of the promising areas for improving pasteurization installations is the use of rotary heaters in them, the special design of which allows, due to molecular friction of the particles of the processed product, to heat the latter to a predetermined temperature. The temperature of the heat treatment of the product depends on the time it is in the rotary heater and can be adjusted over a wide range. At the same time, the product is subjected to homogenization.

The safety of perishable and dairy products has always been and remains relevant at all times. The presented equipment for milk meets the most modern requirements for its collection, storage and further processing.

All components of the units are made of high-quality and high-strength food-grade materials that meet the conditions of sanitary standards, as well as the technical parameters applicable to this equipment. The body of the milk plant, regardless of shape and volume, is made of heat-insulating materials to reduce energy consumption and reduce heat loss to the environment.

All milk equipment has a control system with metering devices and control of production processes.

It is also mandatory to have washing and mixing installations to maintain a homogeneous mass of the dairy product, uniform distribution of any auxiliary components, whipping, etc.

When choosing, you can also specify additional equipment for the convenience of servicing the dairy unit, calculate the required consumption and determine the size of the required containers.

Pasteurization and cooling plants for milk

In addition to the function of preservation and processing in the form of pasteurization, it also has regenerating and cooling properties.

Only natural resources are used as a refrigerant and heat carrier in the equipment - ordinary water purified by hard filters, which is heated, or vice versa, cooled to the required temperature and passed through plate pipes through a tank with milk.

The installation itself consists of a reservoir that receives milk and water with the help of a pump, the supply and output pumps themselves, a lamellar water circulation unit, temperature modules for heating and cooling water for production needs, an automatic production control panel, liquid volume control sensors and warning systems for the case of a decrease or increase in the minimum allowable level, as well as deviations from the specified technical processes.

The equipment requires sufficient overall space for placement. When launching a pasteurization plant and a pasteurization and cooling plant for milk, it is necessary to have steam outlet pipelines, as well as mechanically filtered cold water supply, power supply of at least 230V with the possibility of grounding, floor drain and drainage systems, and sewerage.

Pasteurization plant and pasteurization and cooling plant for milk designed for heat treatment of dairy products without losing its main properties.

Using gentle processing methods, protein, sugar and fat molecules remain unchanged in milk. The principle of their operation is that milk sequentially flows from one tank to another, gradually mixing with already heated milk and, finally, its entire volume is heated to the temperature necessary for regeneration and maintained for the required time (milk - 30 seconds, fermented milk mixtures - 300 sec.) at pasteurization temperature.

After heat treatment, the product is cooled and can be filled and packaged.

All parameters of the production process are automatically registered and controlled by special sensors. If there are any deviations from the specified modes, the dairy product is sent for secondary pasteurization. At the same time, the warning system is triggered, the backflow valve opens and the regeneration process starts again.

Plants for the production of powdered milk

It is somewhat different from the equipment used for drying other food products. In the dairy industry, an indicator of the quality of powdered milk is its solubility, that is, when interacting with a liquid, the product must quickly break down into molecules and mix with it. And this is exactly what it becomes thanks to the phased technological process of its drainage.

When installing and starting up the milk powder production unit, the room where the unit is supposed to be installed must comply with sanitary and building standards. It is obligatory to have sewerage, water supply, electricity from 220V, ventilation hood, walls and floors must be tiled or plastic.

The production technology of powdered milk consists of several stages: milk supply, filtration, measurement and determination of fat content, pasteurization and cooling. After that, it enters the sublimation chamber, where it first thickens, then it is brought to a homogeneous consistency and after that it is dried.

Pasteurization in the manufacture of milk powder is necessary to destroy various kinds of microbes, dissolve somatic cells in it to achieve a homogeneous liquid. In addition, milk, before becoming a powder, goes through several degrees of purification. The more and better filters, the better.

As a raw material, you can use the lowest fat milk with a high content of somatic cells. It's no secret that our cows often get sick with mastitis and organic matter gets into the milk. After a series of filtering and processing, this problem is solvable.

What else is beneficial installation of the production of powdered milk?

In addition to dairy products, this equipment can produce egg powder, make cheeses, soup bases, etc.

In the market of goods and services, dairy products are in special demand. And the questions of their suitability for consumption, shelf life and quality are always of concern to the consumer.

Freeze-dried milk is widely used in the production of cosmetics, in cooking, various baby food is made from it by mixing and adding certain fillers, animal feed, it is restored, preserved, and even some fermented milk products are made on its basis.

Under certain storage conditions, it has an extended shelf life, it retains all the beneficial properties of real cow's milk, which is extremely important, for example, for the regions of the Far North.

Examples of modern milk installations are demonstrated at the annual Agroprodmash exhibition!

company PROJECT-P developed (APCS) a plate pasteurization and cooling plant for dairy products based on the equipment of OWEN and Weintek.

The quality of dairy products produced at dairy plants is largely determined by the quality of product pasteurization. In turn, the quality of pasteurization depends both on the exact thermal calculation and assembly of the pasteurization unit, and on the automatic control system for the pasteurization process. In the food industry, there are many different pasteurization plants: tubular, lamellar, ultrasonic, etc. The most common is the installation on a plate heat exchanger, such an installation is easy to manage and has good energy performance. The energy efficiency of plate pasteurization plants is ensured by regeneration sections, where the product entering the plant is preheated by cooling the already pasteurized product.

In most cases, plate pasteurization plants have a product heating/cooling section at the outlet of the plant, where the product is either heated or cooled, depending on the process. Therefore, in the general case, they speak of plate pasteurization-cooling units (hereinafter referred to as PPOU).
There are many varieties of PPOU, the classification of differences of which can be divided into the following groups:
1. Equipment connected to the pasteurization plant (deaerator, separator, homogenizer).
2. Presence of a holder (60sec, 300sec).
3. Number of regeneration sections.
4. The presence of a heating section or a cooling section at the outlet of the unit.
The figure "Technological scheme" (see below) shows a diagram that combines all types of PPOU.

Most manufacturers of food equipment (in particular, manufacturers of POU) are guided by a foreign manufacturer of electronics and software when designing automated process control systems (for example: Siemens, OMRON, Mitsubishi Electric, etc.), which in turn leads to a high cost of PPO. The use of OWEN equipment makes it possible to significantly reduce the cost of PPOU (about several hundred thousand rubles). APCS PPOU built on the equipment of OWEN and Weintek is practically not inferior in terms of functionality and quality of automatic control and regulation of APCS built on the electronics of such world leaders as Siemens and OMRON. The main element of the APCS PPOU is a control panel based on a programmable logic controller, to which actuators and sensors are connected.

The main equipment of the control panel of the APCS PPOU:
— 1 programmable logic controller ARIES PLC160;
— 1 discrete input module ARIES MV110-224.16DN;
— 1 discrete input module ARIES MV110-224.32DN;
— 1 universal analog input module ARIES MB110-224.8A;
— 1 discrete output module ARIES MU110-224.32R;
— 1 frequency converter ARIES PChV;
- 2 power supplies ARIES BP60-D4;
— 1 operator panel Weintek MT8070iE;
— electropneumoconverters and pneumatic distributors SMS;
— electrical accessories (circuit breakers, electromagnetic starters, electromagnetic relays) ABB.

Description of the technological process:

Technologically, pasteurization of dairy products consists of 5 processes: sterilization process, pasteurization process, alkaline washing process, acid washing process, rinsing process.

STREILIZATION PROCESS
The sterilization process is the process of thermal disinfection of an installation. Runs before the product pasteurization process.
When the sterilization process is started, the pumps of the hot water circuits of the pasteurization and heating sections, as well as the product pump, are switched on. The valve for supplying water to the receiving tank opens. When the upper water level in the receiving tank is reached, the water valve is turned off. The steam valves of the pasteurization and heating sections open. Depending on the temperature of the water at the outlet of the pasteurization section and the heating section, the degree of opening of the steam control valves is regulated. Consistently, in a semi-automatic mode, the following are connected: deaerator, separator, homogenizer. As soon as the water temperature in the unit reaches the sterilization temperature setpoint, the sterilization time starts. At the end of the sterilization time countdown, the steam supply is cut off and an audible alarm sounds. In semi-automatic mode, the following are switched off: deaerator, separator, homogenizer, the unit stops (pumps are switched off, valves return to their initial state), the sterilization process is over.
During sterilization, the unit periodically switches between return and circulation circuits.
Return circuit: receiving tank - return valve - receiving tank. Circulation circuit: receiving tank - return valve - holding valve - circulation valve - receiving tank.

PASTEURIZATION PROCESS
The pasteurization process consists of 4 sub-processes: heating the plant to the pasteurization temperature, pushing out water, bottling, pushing out the product.
Unit warm-up:
When the pasteurization process starts, the pumps of the hot water circuits of the pasteurization and heating sections, as well as the product pump, are turned on. The return valve opens. Depending on the technological process, a sustainer is connected. The valve for supplying water to the receiving tank opens. When the upper water level in the receiving tank is reached, the water valve is turned off. The steam valves of the pasteurization and heating sections open. Depending on the temperature of the water at the outlet of the pasteurization section and the heating section, the degree of opening of the steam control valves is regulated. Consistently, in a semi-automatic mode, the following are connected: deaerator, separator, homogenizer. As soon as the water temperature reaches the pasteurization temperature setpoint, an audible signal sounds, informing the operator that the unit is hot and the water pushing sub-process can be read. Heating of water (product) proceeds during all process of pasteurization.
Water push:
The water pushing sub-process consists of the product pushing the water out of the plant into the sewer. When the water is pushed out, the circulation valve opens. The filling valve switches to drain. Water is being drained into the sewer. Depending on the technological process, the product is either heated or cooled at the outlet of the plant. During cooling, the steam valve of the heating section is closed, the warmed water discharge valve is opened, the exit and ice water inlet valves are opened sequentially at intervals of several seconds, respectively. The level of the product in the receiving tank is automatically maintained during the entire pasteurization of the product. From the receiving tank, the product is fed by a product pump to the regeneration section 1, where the product is preheated to a temperature of 40-60C. Next, the product enters the deaerator, after the deaeration process, the product enters the separator, where it is cleaned and enters the regeneration section 2 and is heated to a temperature of 50-70C. From the regeneration section 2, the product enters the homogenizer, after homogenization the product enters the regeneration section 3, and then to the pasteurization section, where it is finally heated to the desired pasteurization temperature. Coming out of the pasteurization section, passing through the switching automatic return valve and holding (60-300 sec), the product goes to the regeneration sections 3, 2, 1 respectively. Further, depending on the production technology, either heating or cooling of the product takes place in the heating / cooling section.
The product is heated and cooled by heat exchange in five sections: in regeneration sections 1, 2 and 3, heat exchange occurs between the initial cold product and the hot pasteurized product. In the pasteurization and heating/cooling sections, heat exchange takes place between the product and water. At the end of the water ejection time countdown, the bottling valve switches to bottling - the product bottling sub-process starts automatically.
Bottling:
During the product bottling sub-process, the bottling line is controlled by the product pressure sensor at the outlet of the plant. When the pressure of the product at the outlet of the unit rises above 2 kg/cm2, the unit stops and an accident is generated in the bottling line. The pasteurization temperature of the product is also monitored. When the pasteurization temperature of the product falls below 2’C from the setpoint, the unit automatically switches to return - the underpasteurized product is re-pasteurized. As soon as the pasteurization temperature of the product reaches the pasteurization temperature setpoint, the unit automatically switches back to bottling the product. When the product level in the receiving tank falls below the set minimum level, the unit automatically switches to circulation. An audible signal sounds to inform the operator that the product has run out. In this case, the operator has two options: the first is to connect another tank with the product to the installation and restart the filling, the second is to start the process of ejecting the product.
Product ejection:
The product ejection sub-process consists of water displacing the product from the plant as well as from the bottling line. When starting the ejection of the product, the circulation valve opens, the filling valve is in the filling position. As soon as the receiving tank is empty, the valve of water into the receiving tank opens and the product ejection timer starts. At the end of the product ejection time countdown, the unit switches to circulation, the steam supply is shut off, and an audible alarm sounds. In semi-automatic mode, the deaerator, separator, homogenizer are switched off, the plant stops, the pasteurization process is over.

ALKALINE AND ACID WASHING PROCESSES
The alkaline and acid washing processes are started after the pasteurization process. Necessary for the complete removal of dairy residues from the installation.
When the process of washing with alkali (acid) is started, the pumps of the hot water circuits of the pasteurization and heating sections, as well as the product pump, are turned on. The valve for supplying water to the receiving tank opens. When the upper water level in the receiving tank is reached, the water valve is turned off. The alkali (acid) supply valve opens and the dosing timer starts. During the dosing time, the alkali (acid) dosing pump is switched on and off periodically. This is necessary for uniform distribution of cleaning solutions throughout the installation. At the end of the dosing of detergent solutions, the valves of the steam sections of pasteurization and heating open. Depending on the temperature of the water at the outlet of the pasteurization section and the heating section, the degree of opening of the steam control valves is regulated. Consistently, in a semi-automatic mode, the following are connected: deaerator, separator, homogenizer. The receiving tank washing valve opens. As soon as the temperature of the water in the system reaches the alkaline (acid) washing temperature set point, the washing time begins. At the end of the washing time countdown, the steam supply is cut off and an audible alarm sounds. In semi-automatic mode, the following are switched off: deaerator, separator, homogenizer, the unit stops, the washing process is over.
During washing, the unit periodically switches between the return and circulation circuits.

RINSING PROCESS
The rinsing process follows the washing process and is necessary to completely remove cleaning solutions from the pasteurization plant. When the rinsing process is started, the pumps of the hot water circuits of the pasteurization and heating sections, as well as the product pump, are switched on. The rinsing process timer starts. The return and circulation valves open. The filling valve switches to drain. After emptying the receiving tank, the valve for supplying water to the receiving tank opens. During the rinsing process, the water level in the receiving tank is automatically maintained. During warm rinsing, the steam valves of the pasteurization and heating sections open and, depending on the temperature of the water at the outlet of the pasteurization and heating sections, the degree of opening of the steam control valves is regulated. Consistently, in a semi-automatic mode, the following are connected: deaerator, separator, homogenizer. At the end of the rinsing time for warm rinsing, the steam supply is cut off and an audible alarm sounds. In semi-automatic mode, the following are switched off: deaerator, separator, homogenizer, the unit stops, the rinsing process is over.
During rinsing, the unit periodically switches to drain, circulation and return.

Additional information on APCS PPOU:

Air pressure control.
The automation of the pasteurization plant controls the air pressure at the inlet to the control panel using the pressure switch of the air preparation system. When the air pressure drops below the allowable value (4-5kg/cm2), an alarm is generated and the unit stops.

Power supply control.
The automated process control system monitors a three-phase AC network by a signal from a voltage and phase control relay. In the absence of a signal, the installation stops, a power supply failure is generated.

Overheating control.
The PPOU implements overheating control in the pasteurization and heating sections. If the heat carrier temperature exceeds the maximum heat carrier temperature setpoint, the steam supply to the corresponding section is stopped until the heat carrier temperature drops below the maximum heat carrier temperature setpoint. An overheating warning is generated in the corresponding section.

Heat transfer control.
During pasteurization of the product, the temperature difference between the heat carrier and the product in the pasteurization and heating/cooling sections is controlled. If the modulus of the product temperature difference and the heating medium temperature becomes higher than the maximum heat transfer temperature difference setting, a low heat exchange warning is generated in the corresponding section. Violation of heat transfer is associated with the boiling of the product on the walls of the heat exchanger plates.

Control of water leakage in the system.
During operation of the installation on water in a closed circuit (sterilization, pasteurization - heating of the installation, washing with alkali, washing with acid), the water level in the receiving tank is monitored. When the water level drops below the low level sensor, the unit stops and a water leakage alarm is initiated in the system.

The position of the washing solution line.
The washing solution supply line has two positions: the "pasteurization" position (sterilization, pasteurization, rinsing) and the "washing" position (washing with alkali, washing with acid). When starting each process, the position of the cleaning solution line is checked, if the position line does not correspond to the process being started, the process will not start and an alarm message will be generated.

Equipment operation control.
The operation of the deaerator, separator, homogenizer, pumps and pneumatic valves is controlled by feedback. If the feedback from the equipment disappears during the operation of the POU, then an accident of the corresponding equipment is initiated and the PPO stops.

Make-up of pasteurization and heating/cooling circuits.
The hot water circuits of the pasteurizing and heating/cooling sections are automatically fed with tap water when the water pressure in the circuits decreases. If the pressure in the hot water circuit does not reach the setpoint (2kg/cm2) within a certain time, then an emergency is generated for the corresponding circuit.

Manual control.
The control of the actuators of the PPOU is carried out both in automatic and manual modes using the MT8070iE panel, and switching between automatic and manual modes is also possible during operation of the unit.

Connection of deaerator, separator, homogenizer.
Depending on the product processing technology, it is possible to connect any combination of the following equipment: deaerator, separator, homogenizer. The unit is started up without a deaerator, separator, homogenizer, then this equipment is connected in series to the unit. The deaerator, separator and homogenizer have their own control panels, from which signals about the operation of the equipment are sent to the PPOU control panel. Based on the feedback signals, the product supply valves (inlet, outlet, bypass) are switched to the corresponding equipment.

Product temperature control.
The pasteurization temperature and product outlet temperature are controlled by controlling the supply of steam or ice water to the pasteurization and heating/cooling section. The PLC160 programmable controller polls the product temperature sensors continuously; temperature information is fed to the PID controllers, which provide control signals (4-20mA, 0-10V) to the steam control valves.

Product pump control.
Product pump performance is controlled by changing the speed of the product pump motor through a frequency converter. Information from the product flow meter is processed by the PLC PID controller, which issues a control signal to the frequency converter (4-20mA, 0-10V).

Light and sound indication.
A three-color signal tower is used for light and sound indication in the APCS TPOU. When the process is running, the green indicator is on. An orange indicator lights up when warnings occur. In case of accidents, the red indicator lights up. At the end of the processes, as well as in the event of warnings and alarms, an audible alarm sounds.

Visualization.
Visualization of information, as well as control of the installation is carried out through the Weintek MT8070iE operator panel. The panel sets the temperature and time settings for the processes, the dosing time for cleaning solutions, the time for one dose and pause, the product pump performance, the settings for PID controllers, timers, and much more. Also, the MT8070iE panel displays the PFOU flow diagram, event log, process pressure and temperature graphs, warnings and alarms, and informational messages about the PFOU operation.

Registration of technological parameters.
Registration of technological parameters is carried out by the Weintek MT8070iE operator panel on a USB flash drive in *.cvs files (Microsoft Excel). An event log (discrete process variables) and pressure and temperature graphs (analogue process variables) are written to the USB flash drive.

Connection to SCADA system.
The APCS PPOU implements the possibility of remote control of the technological process through the SCADA system MasterSCADA. Connection of a remote computer to PLC160 is carried out via the Ethernet communication interface, Modbus-TCP communication protocol.

The cost of process control system for pasteurization and cooling plant.

Pasteurization-cooling plant

Pasteurizing cooling plant for milk- this is equipment designed for in-line heating of milk to the pasteurization temperature, holding at the pasteurization temperature and subsequent cooling. The pasteurizing and cooling plant for milk is one of the most important pieces of equipment in the dairy industry, which allows you to destroy all vegetative forms of microorganisms, making the product safe for consumption.

LLC "KR-Tech" produces multi-mode pasteurization and cooling units that can be used in the receiving and equipment areas of dairy industry enterprises of any size. Our plants for in-line pasteurization of milk are made on the basis of plate heat exchangers, which have been successfully used for a long time in many milk processing enterprises.

A multi-mode pasteurization cooling plant for milk compares favorably with other types of milk pasteurizers by the possibility of their use in several technologies at the same time. This equipment can be used simultaneously in technologies:

1. Production of drinking pasteurized milk;
2. Production of fermented milk products (kefir, curdled milk, matsoni, etc.)
3. Curd production;
4. Cheese production.

Thus, the use of multi-mode pasteurization and cooling plants for milk provides significant savings in capital investments and can significantly reduce the occupied production area.

The pasteurization cooling unit for milk manufactured by KR-Tech LLC has the following parameters:

In the designs of pasteurization and cooling plants, it is possible to connect additional technological equipment. Such equipment can be:

1. Cream separator and/or milk separator and/or bactofuge;
2. Deodorization plant for milk;
3. Plunger homogenizer

In the case of purchasing additional equipment, it can be integrated into a single automated control system, as was implemented in. In addition, downstream equipment, such as tanks, can also be integrated into the control system.

A typical pasteurization cooling plant for milk includes:

1. Tank-balancer for the product;
2. Product pump;
3. Multi-section plate heat exchanger;
4. Tubular holder;
5. Primary coolant supply and condensate removal system;
6. Secondary coolant preparation system;
7. Coolant supply systems;
8. Installation control panel;
9. Set of pneumatic valves, fittings and pipelines.

As options, our Customers can choose:

1. CIP-washing system;
2. System for measuring productivity and dosing of the volume specified by the program;
3. System for maintaining excess pressure of the pasteurized product, complete with a pressure maintaining valve and a centrifugal pump;
4. Safety valve on the product outlet line from the homogenizer

In accordance with one of our principles, we use only proven technological components from the world's leading manufacturers, namely:

1. Plate heat exchangers — API Schmidt-Bretten (Germany), Alfa-Laval (Sweden), GEA (Germany);
2. Steam system components — Spirax Sarco (England), ADCA (Portugal);
3. Automation components - Endress-Hauser (Germany), Anderson-Negele (Germany);
4. Electrical components — Siemens (Germany), Omron (Japan);
5. Pneumatic components - SMC (Japan);
6. Fittings — Kieselmann (Germany), Alfa-Laval (Sweden), Inoxpa (Spain)