Мембранды үрдістер

In the dairy industry, disk spray dryers are mainly used for drying milk and dairy products. The rotation of the spray disc for spraying the product is carried out by electric motors with a gearbox, high-quality electric motors. The exhaust air is cleaned by cyclones or bag filters.

Determination of the quality of condensed milk entering the drying process

,

Where W is the amount of evaporated moisture, kg / h,

In condensed milk, %;

Amount of dry product after drying

Air consumption for drying

For spray dryers, the air flow rate is determined by the formula:

W - the amount of evaporated moisture, kg / h;

moisture content of the air in front of the heater, kg / kg of dry air
- moisture content of the air at the exit of the dryer, kg / kg of dry air at the exit ( and determined by the diagram s-d)

It is recommended to convert the air parameters found in the s-d diagram to the dimension in the J-x diagram.

The heat loss in spray dryers is . The actual air consumption for drying is

The amount of heat required to heat the air in the amount calculated by the formula

Where Lg is the actual drying air consumption, kg / h

- heat content of the air before entering the heater, J / kg

3. Principle of operation

The A1 – ORCH drying unit is designed for drying condensed skimmed and condensed whole milk, as well as whole milk substitutes with a fat content of up to 30%.

It is used in the dairy-canning, butter-making and cheese-making industries. From the vacuum device, condensed milk passed through the homogenizer enters an intermediate tank, from which a screw pump under pressure is fed to a spray disc mounted on the shaft of the milk sprayer and having a rotation speed of 12000min, sprays condensed milk to the drying tower milestone, into which dry hot air heated in the heater is fed from above.

The cold air is cleaned of dust in the air filter, pumped by a fan into the heater, heated by steam to 170 and enters the drying chamber through the air distributor.

The milk sprayed in the drying bath, washed by a stream of hot air, dries quickly and falls to the bottom of the drying tower, from where the scraper is not on the low through the hole is removed to the shisk.

Air with the smallest particles of powder through a pipe in the lower part of the drying tower enters the cyclone battery for cleaning, first in the upper cylindrical part tangentially to the cyclone circumference.

The central forces during the movement of the dust particles are thrown to the outer wall of the cylinder and then into the conical part. With the help of sluice gates, the powder is removed from the cyclones. The air purified from the powder from the cyclones is sucked out by the main method, which releases it into the atmosphere. The powder removed from the drying tower is transported by a screw through the airlock to the pneumatic transport line, where it is cooled by air, which is sucked into the pneumatic transport line from the premises through an air filter and a heater.

The air cooled from the heater, entering the pneumatic transport line, picks up the powder and transfers it already cooled to the cyclone-unloader, which ends with a lock gate. The powder enters the hopper through the sluice gate, and the air released from the powder is transferred by a fan to the cyclone battery for re-cleaning. The powder accumulates in the hopper, which is fed to the automatic machine for filling and packaging dry dairy products in paper bags with a polyethylene liner. From the drying tower, the milk dispenser can be lifted by an electric hoist.

4. Completeness

The set of the drying unit includes:

Control and control panel;

Compressed air supply system;

Bunker;

Food delivery system;

Installation of a heater and fan;

Exhaust air extraction system;

Cooling system and transportation of the product;

Service area system;

Washing system;

Two milk sprayers;

Single-screw pumping unit;

Semi-automatic weight dispenser;

Plastic Film Welding Machine;

Sewing Machine;

Pulse-dynamic cleaning system;

Electric hoist;

5. Sanitary treatment of drying plant equipment

The drying line includes a drying chamber, cyclones, convective vibrating dryers, vibrating containers, bucket elevator, air ducts. The sanitary treatment of this equipment includes two stages: dry cleaning and wet treatment (washing) with alkaline solutions, followed by disinfection or sterilizing with hot air.

Dry cleaning of the sluice gates of the defect, the vortex gate, the suitable channel and the force is carried out as necessary. Dry cleaning of the drying equipment is carried out daily at the end of the work in the following sequence:

Remove the spray disc and use the drying brushes to manually remove the remaining dry powder from the walls of the equipment, while turning on the suction fan to completely remove the remaining powder.

Release the filters by shaking from the particles by shaking from the particles of milk powder, if the filter sleeves are very dirty and shaking does not give results, then they should be washed (the filters should be changed at least after 25 days or according to the instructions in the operating instructions.)

Clean the brushes from the particles of milk powder hopper, blinds, auger, the lower part of the turbine.

Wet cleaning of the drying equipment is carried out weekly with cleaning solutions after 250 hours of operation. Before washing, carry out preparatory work:

Remove the rotors in the lock and clean them manually (the rotors in the fluidized bed system are not dismantled);

Install the cleaning turbine in the drying chamber;

Mount the funnels;

Turn on the airlock engines;

Perform a general inspection of the installation check the tightness of the installation;

Disconnect the cooling and transport channel from the air conditioning section;

Connect the equipment to the washing plant (station)

Apply water through the throttle to the p chamber (17) for 5-7 minutes;

Rinse with water (30) for 10-15minutes;

Rinse with an alkaline solution by recirculating it at 60-65, for 30-40 minutes;

Rinse with water (30) for 10-15minutes;

Disinfect the inner surface by treating with hot water (95) for 10-15 minutes or treat with a disinfectant solution (30-40) for 7-10 minutes;

Dry the surface with hot air (90-100) for 1-2 hours.

Note

Cleaning according to the above designated points can be carried out each in relativity all the higher, i.e. repeated use of detergents is insignificant.

Clearing the line filed. Before cleaning, connect the return pipe together, located directly in front of the sprayers, the sensing emulsion passes through the feed pump of the bypass system, the double filter and the feed line to the cleaning tank, while the feed pump is running.

Pneumatic transport is subjected to dry cleaning and wet treatment after each drying:

Clean the surface of the pneumatic transport with water with a hydraulic gun until the dry product remains are removed as much as possible;

Wash the surface of the pneumatic transport with an alkaline cleaning solution for 20-30 minutes:

Rinse the surface of the pneumatic transport with water until the nitrile reaction of the rinse aid is obtained.

List of information sources used

Abolmasov G. F., et al. Examples and tasks for the course of technological equipment of dairy industry enterprises. (1966.)

Magazine "milk processing" No. 5,6,7/ 2009.

Industry catalog "Technological equipment for the dairy industry»

Catalog of installed drawings of technical equipment for the dairy industry. (1984.)

Passports, technical description and operating instructions of the technological process, equipment of the dairy industry.