Diploma project Refrigerating compartment calculation

Introduction

Cold is a fundamental criterion in the process of preserving the qualities, properties and appearance of any food product for the time it will take to realize it.

Refrigeration systems are used in the meat and dairy industry, in the production and processing of poultry and fish products, and in the storage, transportation and processing of fruit and vegetable products.

During storage, most foodstuffs are subject to undesirable changes due to deterioration of taste and nutritional value, and sometimes to their complete disrepair. The question of their preservation worried man from ancient times [1].

Changes in food products are also caused by biochemical processes controlled by enzymes, which are natural catalysts for chemical reactions.

The meat industry is one of the main branches of the national economy that provide the population with full-fledged food.

Currently, most meat products are stored and processed in large enterprises equipped with high-performance equipment, which ensures high quality of products. However, practice has shown that, despite the advantages of large industrial production, it is advisable in many cases to organize the processing of perishable livestock products in smaller and medium-sized enterprises located mainly in the depths of the raw material zone.

Such plants and workshops, the number of which is constantly growing, bring great benefits to the national economy, provided that the production of products is organized using advanced technologies and modern methods of controlling the entire technological process.

The design of modern enterprises for the storage and processing of livestock products is mainly carried out by specialized research institutes, but, nevertheless, the graduates of the Faculty of Technology should have the skills to select equipment taking into account not only its purpose and productivity, but also economy, compliance with environmental requirements.

The purpose of the discharge work is to develop a storage chamber for poultry meat with a capacity of 2500 tons.

The tasks of graduation work are to develop measures that contribute to improving the quality of products, to find ways to reduce quantitative and qualitative losses of products during storage.

1. Process Part

1.1 Characteristics of the modern state of the workshops on primary poultry re-work.

The domestic poultry processing industry currently has about 650 poultry processing enterprises and workshops with an average capacity of 1,100 tons per shift. Their technical equipment is based on conveyor lines with a capacity of 5003,000 heads per hour. More than 30% of the lines have been in operation for more than 10 years and need to be replaced. Labor productivity on domestic lines is 2 times lower than on the lines of a number of foreign firms. Complete lines are not issued.

Poultry slaughter and treatment takes place on in-line mechanized lines according to traditional technology and consists of well-known sequential operations, including semi-destruction and complete shredding, characterized by a high proportion of unclaimed waste, not used at all or used extremely irrationally.

During processing, poultry receives food, technical and fodder products. Food products include poultry meat in carcasses, intended for sale and industrial processing, processed by-products (liver, heart, muscle stomach), neck, head, leg; technical products - feather puff raw materials, fat from stomachs and glandular stomachs; to fodder - processing waste (blood, esophagus, zoba, gallbladders, trachea, spleen, ovaries, seeds, cuticles).

The yield of food products is determined by the processing technology. In natural and value terms, the yield of products is greater when processed with complete poultry rippling.

In a market economy, the poultry processing industry of Russia faces the tasks of intensifying the processing of poultry and poultry products, improving the quality and expanding the range of products, and technical re-equipment of enterprises.

1.2 Analysis of process organization in poultry primary processing shop

Primary poultry processing consists of the following sequential main operations: receiving, weighing, removing from cells and hanging the bird on the conveyor, electric damping with alternating current of industrial frequency or pulse current, slaughter and bleed, removal of the fly and tail feather, weakening the retention of the plumage in the poultry carcasses (spark and underpark with hot water), removal of plumage from poultry carcasses, semi-removal or rubbing of carcasses, washing of carcasses from inside and outside and drying of carcasses surface, moulding, cooling, sorting, marking, group weighing, packing carcasses and marking of boxes, sending carcasses to the refrigerator for storage or freezing.

Bird slaughter can be produced in various ways. In all cases, when choosing the method of slaughter, they are guided by safety considerations for the fighter, humanity, simplicity of the method, veterinary and sanitary requirements and the need to obtain full and benign poultry meat and other products. The degree of bleeding of the bird carcass is one of the most important factors affecting the quality of meat, therefore, first of all, when slaughtering a bird, this should be paid attention to.

- organization of reception and pre-slaughter maintenance of poultry:

Method of delivery is selected according to data of techno-economic equipment of poultry plant construction or reconstruction. When designing typical poultry mills, the method of delivery is adopted, as a percentage of the daily capacity of the poultry primary processing workshop: 90 by road; by rail - 10.

Poultry acceptance from suppliers is carried out in a room isolated from other poultry production shops. The bird is taken according to the bill, living mass and species. The capacity of the reception shop corresponds to the daily production capacity of the poultry factory.

The sorted poultry in the receiving shop is weighed in groups and sent to the poultry overexposure shop for overexposure or sitting in accordance with the following schemes.

Reception of land poultry: admission (mainly by road) in boxes, cages - wind inspection and rejection of sick poultry - sorting healthy poultry by sex, age, strength - transplantation into mobile cells group weighing - sending for movement or sitting.

- silencing:

Electric silencing is intended for anaesthetizing live land agricultural poultry by exposing it to electric current using water as a contact medium. You can use a PPPE set for this operation. To supply current in this apparatus, a bath with water or weak brine is used. A post consisting of two channels is fixed on the bed of the apparatus. A carriage moves along the channels on the wheels using a screw gear and a steering wheel. A bath is fixed on it, in which the specified water level is maintained by the float regulator. The bath on both sides is enclosed with plastic shields and isolated from other structures. Current is supplied from electric cabinet to bath and guide mounted on conveyor bearing structures. Stunning occurs after the bird's heads enter the water bath, and the suspension contacts the guide. The stun voltage is controlled depending on the species of the bird in the range from 60 to 210 V. The productivity of the device (heads per 1 hour) is: when stunning the broilers 6000.

All devices using electricity for stunning must be reliably grounded and equipped with blocking devices that disconnect the device during inspections and repairs.

- external slaughter

To do this, take the external slaughter machine B2FTs2L6/4. It consists of post, drive, frame, guides, levers, disk knife, flywheel, guide and key. The rack is used for installation of assembly units and de-tales of the machine, adjustment of the machine by height and is a "pipe in pipe" structure. Height adjustment is performed through conical pair of gears and pair of "screw nut." The drive consists of an electric motor, which, through a cam clutch and a bearing assembly, transmits rotation to a disk knife. The frame is mounted on a post and is used to install guides that form a slot for orienting heads. Levers are necessary for braking the head. The disc knife serves to cut the carotid artery and the jarring vein of the bird .

After electric suppression, carcasses are fed by conveyor to external slaughter machine. The head at the neck level falls into the gap between the guides, after which the lever slows it down until the carotid artery and yoke vein are in the zone of a rotating disk knife. At the same time, the position of the head is oriented with the help of a guide. After opening the bright vein and carotid artery, carcasses enter the bleeding site. Machine capacity 6000 pcs/h.

-extrusion:

Slaughter and bleeding of all types of poultry on conveyors is carried out manually or using automatic machines. For manual slaughter, trays are used, the configuration and length of which correspond to the configuration and performance of the conveyor. The trays are installed under the chain conveyor. The length of the tray should ensure full blood collection, taking into account the duration of bleeding, equal to 1-2 minutes.

Tray 66M is used for slaughter and bleeding of chickens. It consists of a tubular frame on which removable side shields of the guard are installed.

- removal of hens tail unit:

Machine for removal of hens tail unit is mounted on welded frame, on which two rollers are installed. The rollers consist of a shaft and a rubber shell fixed on it, which has a cylindrical and conical parts. Screw thread is applied on cylindrical part and longitudinal thread is applied on conical part. The upper shaft occupies a horizontal position, and the lower shaft is inclined, so that the conical parts contact and the longitudinal cuts engage.

Rollers installed in rolling bearings are driven by electric motor through V-belt gear and bevel gear. In front of the rollers there are turns forming a slot through which the pen passes.

The machine is served by one worker who fills the feathers in the wedge gap between the rollers, then they are moved by screw cutting to the conical part of the rollers, from where they are removed. The shields protect the bird from getting into the rollers.

Machine capacity up to 500 carcasses in 1 h, roller speed 5 s1, drive motor power 1 kW.

-Poultry carcass park:

Bird carcasses of all species are boiled by immersion in hot water. In addition, waterfowl carcasses can be treated in chambers with a steam-air mixture at a temperature of 80... 85 ° C. By immersion in hot water, a complete spark is carried out (when the entire surface of the carcass is treated) or a sub-spark (when the heads, necks, ends of the wings in which the feather is held most firmly are additionally treated).

In the spar chambers, intensive streams of hot water are directed to the carcasses, which must move against the direction of growth and adjoining the plumage skin. This achieves the complete immersion of carcasses in water and the loosening of the feather cover, which intensifies heat exchange. Water flows are created by axial pumps.

We use a two-section apparatus with pumps in side pockets, which consists of a middle section, to which a foam extinguisher is attached on the front side, and on the opposite side a rotary section. Body of sections of rectangular shape, welded, reinforced with frame from angles. In the side walls of the body, windows are made on which pockets are fixed, which pass in the upper part into a bell located along the entire section. The bell is closed by a cover from above, and on the inner side there is a slot through which water is supplied under pressure to the inner body. Axial three-blade propeller water pump is installed in pocket. Pump impeller is attached on shaft rotating in spherical, radial and thrust bearings. Pump is driven by motor through V-belt drive. Two pumps are installed on each section. The water in the apparatus is heated by hot steam. To warm up the water before the start of operation, three ejectors are included, and the temperature is maintained with one or two. Temperature controller provides temperature deviation within 0.5 ° С .

- removal of plumage from poultry carcasses:

To remove the plumage from the carcasses of the bird, machines of various designs have been created using roller, plate and drill tools. The variety of machines is caused by the difference in the forces of holding the plumage in a bird of the same species and by the even greater difference - in birds of different species. The removal of plumage is one of the most time-consuming technological operations of slaughter and primary processing of poultry. In manual processing, it takes up to 80% of labor costs. Modern machines, connected in a single technological flow with preliminary heat treatment, completely exclude manual labor.

The design of machines and the configuration of technological flows depend on the type of poultry being processed and on the capacity of the flows. Domestic lines were created for processing in 1 hour: 500, 1000, 2000 and 3000 chickens, chickens and broilers.

1.3 Poultry Meat Storage

In the poultry processing industry, refrigeration equipment is used for cooling, freezing, storing poultry meat, cold supply of technological equipment and conditioning of technological premises.

Refrigeration and storage of poultry meat and poultry products should ensure the rapid removal of natural heat and subsequent storage of products with guarantees of quality and safety for human health.

Cooling

For production of semi-finished products and longer storage in unfrozen form poultry meat is pre-cooled. Under industrial conditions, the bird is cooled in air or water, and a combined cooling method is also used.

Main cooling methods:

-combined;

- submersible;

-hydroaerosol-evaporation (air-drop).

Freezing (freezing)

For subsequent long-term storage, poultry meat must be frozen. In freezing processes, low-temperature refrigeration equipment is used. The faster the freezing process proceeds, the higher the quality of the product, its storage resistance, and less drying.

The main freezing methods are:

- air;

-contact;

- submersible;

Poultry meat and semi-finished products are stored in medium and low-temperature chambers, depending on the thermal state and technological requirements for the process of meat supplied for storage.

Refrigerators. Storage of chilled and frozen poultry meat.

Defrosting

The process of defrosting poultry carcasses and poultry products in camerachdefrosters, tunnels equipped with air conditioners or calorifers and a system of air channels was most widespread.

Industrial air conditioning

Industrial conditioning is designed to maintain optimal temperatures during processing of chicken in a poultry farm, cooling of expedition premises and transport corridors, maintaining the necessary climate in incubators and production shops. The following types of conditioning are distinguished:

- comfort conditioning;

-comfort-technological conditioning;

-technological conditioning;