Milk Production Line

Contents

PAPER

LIST OF GRAPHIC DOCUMENT SHEETS

INTRODUCTION

1. OVERVIEW OF LITERARY SOURCES

1.1 Raw material for curd production

1.2 Main Equipment

1.2.1 Milk storage tanks (tanks)

1.2.2 Milk and dairy pumps

1.2.3 Cottage Cheese Maturation Baths

1.2.4 Pasteurizers

1.2.5 Cottage cheese compressors

2. DESCRIPTION OF CURD PRODUCTION TECHNOLOGY

2.1 Production technology contains the following stages

2.1.1 Acceptance

2.1.2 Cleaning and pasteurization

2.1.3 Cooling

2.1.4 Fermentation, fermentation, mixing

2.1.5 Pressing and cooling

2.1.6 Bottling, packing

2.1.7 Marking, storage

3. PROCESS CALCULATIONS

3.1 Calculation of material and heat flows

3.2 Hydraulic calculation

3.3 Material calculation

3.4. Strength calculations

3.4.1 Determination of design parameters of the apparatus

3.4.2 Calculation of housing shell

3.4.3 Calculation of shaft strength, stiffness and vibration resistance

4. SAFETY OF LIFE

4.1 Introduction

4.2 Process Analysis

4.3. Harmful and dangerous factors in the dairy shop

4.3.1 Harmful substances

4.3.2 Microclimate parameters

4.3.3 Ventilation

4.3.4 Noise

4.3.5 Illumination

4.3.6 Electrical safety

4.4 Fire safety

4.5. Emergencies

4.6. Conclusions under BJD

5. ENERGY SAVING

5.1. Problem setting

5.2. Analysis of the existing situation

5.3. Energy Conservation Activities

According to the table, we see that heat energy intensity decreases by 30%, but electricity consumption increases slightly

5.4 Additional Energy Conservation Activities

5.5 Conclusions on "Energy Saving" Section

6. PROJECT FEASIBILITY STUDY SECTION

6.1 Production Flow Chart Improvement

cottage cheese

6.2 Production capacity

6.3 Calculation of total amount of additional capital investments

6.4 Designing Labor and Wage Indicators

6.5 Calculation of design cost of products

6.5.1 Calculation of indicators of cost-effectiveness of investments (additional capital investments)

CONCLUSION

BIBLIOGRAPHIC LIST

Project Description

The topic of the diploma project: "Technological line for the production of cottage cheese."

The purpose of the work: modernization of the curd bath.

The calculation and explanatory note considers the basic hardware and technology diagram of the curd production line with a capacity of 5000 kg/hour for the initial raw material product.

Also, the main part of the explanatory note contains the main technical solutions taken at the design stage of the curd production line, the results of the material heat, hydraulic calculation of the plate-type pasteurizer and the structural calculation of the curd bath are given.

The process line feasibility study is given.

The annual profit will be 2915800 rubles, the payback period of additional capital investments is 0.7 years.

The area of ​ ​ possible application: the production of cottage cheese in the classic "open" way, the production of other products using similar technology.

The explanatory note contains: 88 p., 23 Table, 11 Fig., 32 bibliographic references.

Introduction

In this diploma project, the technological scheme for the production of cottage cheese was developed, the necessary equipment was selected, the pasteurization cooling plant of normalized pasteurized milk was calculated, as well as the design calculations of the curd bath.

The dairy industry is one of the most important branches of the agro-industrial complex for providing the population with food. It is a widely branched network of processing enterprises and includes the most important industries: whole dairy production, butter, cheese making, the production of canned condensed and dry dairy products, ice cream, the production of baby food, whole milk substitutes for young farm animals. Each sub-branch has its own specific features.

Based on the world experience, it is planned to bring the dairy processing industry to a qualitatively new level, which will ensure the resumption of production volumes, improvement of its quality, a significant increase in the assortment and depth of processing of raw materials. In order to solve the tasks, it is necessary to carry out technical modernization, as well as significantly increase the technological level of equipment that is used at small-capacity processing plants.

Today, the state of the dairy industry is characterized by the functioning of enterprises that process from 3 to 500 tons of milk per shift.

Industrial milk processing is a complex complex of interconnected chemical, physicochemical, microbiological, biochemical, biotechnical, thermophysical and other specific technological processes.

In the production of cottage cheese, not all components of whole milk are used, unlike drinking milk and fermented milk products. One of the most important elements is milk fat and protein.

The Sosnovskoye enterprise was founded in 1987 and was designed to produce 15 tons of dairy products per day, currently the plant produces about 30 tons per day; The equipment necessary for the production of products is constantly updated and improved. The number of employees of the enterprise is about 140 people.

Cottage cheese is a fermented milk product, a type of cheese traditional for Eastern and Northern Europe, obtained by fermenting milk and then removing whey. It is officially customary to classify cottage cheese, developed in the traditional way, by its fat content. In accordance with GOST, according to physical and chemical indicators, cottage cheese should correspond to the following categories: defatted, low-fat (1.8%), classic (4.0% - 18.0%) and fatty (19% - 23%).

Overview of literary sources

The dairy industry is equipped with modern processing equipment. The rational use of technological equipment requires a deep knowledge of its features. At the same time, it is important to preserve as much as possible the nutritional and biological value of the components of the raw materials in the produced dairy products.

At the same time, technical refurbishment of enterprises is being carried out, new technological lines and certain types of equipment of different capacities, different levels of mechanization and automation are being installed.

Technological processes of dairy products production consist of separate technological operations, which are performed on different machines and apparatuses, which are assembled into technological lines.

At dairy enterprises, many typical technological operations - milk acceptance, cleaning, heat treatment - are carried out using the same type of technological equipment.

1.2 Main Equipment

Let us consider the structure and principle of operation of the main equipment of the curd production line, and give it a comparative characteristic with respect to similar technological equipment.

Description of curd production technology

2.1 Production technology contains the following stages

- milk acceptance;

- milk normalization to the required composition;

- cleaning and pasteurization of milk;

- cooling of milk to the fermentation temperature;

- introduction of starter and rennet enzyme into milk;

- Milk fermentation;

- clot cutting;

- serum separation;

- pressing and cooling of curd;

- packing;

- packing and storage of finished products.

2.1.1 Acceptance

Milk is taken from dairy farms, as well as from receiving points collecting milk from the individual sector located in the area of ​ ​ the plant, in accordance with existing requirements. Milk should be whole, fresh, received from healthy cows, which is confirmed by a certificate of veterinary and sanitary well-being on the dairy farms of suppliers, issued by a veterinary specialist for a period of not more than 1 month. Organoleptic indices, fat content, acidity, density, purity, temperature are determined in milk before shipment in car tanks to city dairy plants.

Milk quality indicators before shipment shall comply with the following requirements:

acidity, ° T 16-18 (for pasteurized not higher than 19 ° T);

density, g/cc. cm, not lower than 1.027 (or not lower than the density of milk produced in a given area);

purity, gr., not lower than II;

reductase sample, class, not lower than II;

sample for phosphatase - negative (in the case of delivery of pasteurized milk).

2.1.2 Cleaning and pasteurization

Heat treatment or pasteurization is the process of heating milk from 63 ° C to a temperature close to the boiling point.

This process was named after the famous French scientist Louis Pasteur (1822-1892), who first used this method to kill microorganisms in wine and beer.

The effect of pasteurization on microorganisms contained in milk depends on the temperature to which the milk is heated and the duration of holding at this temperature.

By pasteurization, microbes are destroyed without a noticeable change in the organoleptic properties of milk (taste, smell and consistency), tuberculosis, brucellous and other pathogenic bacteria are destroyed.

In usual combined milk 99% of bacteria only on condition of the good, reliable sterilization of the equipment, stock, ware used in the course of pasteurization perish. So, an additive to pasteurized milk of contaminated milk containing 1 billion bacteria (i.e. such an amount, which may remain undetected in the milk inventory), will increase the number of bacteria in milk to 1 million in 1 ml. These bacteria will actively multiply and will inevitably lead to spoilage of all milk.

Pasteurization is the easiest and cheapest way to disinfect milk.

Milk is also pasteurized in the production of all dairy products in order to protect them from subsequent undesirable processes that are caused by the vital activities of bacteria and especially E. coli, oily acid bacteria, etc.

In practice, three pasteurization regimes are applied:

during prolonged pasteurization, milk is heated to 63-65 ° C and kept at this temperature for 30 minutes;

Short-term pasteurization is carried out at 72-75 ° C with exposure for 15-20 s, which is carried out in a stream;

instant pasteurization - heating of milk to a temperature of 85-90 ° C without exposure.

The designed technology uses a method of instantaneous pasteurization.

The thermal effect on milk leads to some changes in its constituents. When heated from milk, the gases dissolved in it volatilize. Due to the removal of carbon dioxide, the acidity of milk decreases by 0.5-1 ° T.

At temperatures above 85 °, casein partially changes. But milk albumin is most affected: at 60-65 ° C, it begins to denature.

It is violated during pasteurization and salt composition of milk. Soluble phosphate salts are converted to insoluble salts. From the partial coagulation of proteins and the formation of insoluble salts on the surface of heating devices (pasteurizers), a sediment is deposited - milk stone (sugary).

Pasteurized milk is slower to coagulate with rennet. This is due to the precipitation of calcium salts. Addition of calcium chloride solution to such milk restores its ability to coagulate

2.1.3 Cooling

Pasteurized milk is cooled in the recovery section of the plate pasteurization cooling plant 5 to the fermentation temperature (in the warm season up to 28-30 ° C, in the cold season - up to 30-32 ° C) and sent to special baths 6 for fermentation. Starter for curd production is made on pure cultures of mesophilic lactic-acid streptococci and introduced into milk in amount from 1 to 5%.

2.1.4 Fermentation, fermentation, mixing

Starter for curd production is made on pure cultures of mesophilic lactic-acid streptococci and introduced into milk in amount from 1 to 5%. The duration of fermentation after leavening is 6-8 hours.

At accelerated method of fermentation 2.5% of starter prepared in starter 10 on mesophilic streptococcus cultures and 2.5% of thermophilic lactic-acid streptococcus are added to milk. The digestion temperature with the accelerated method increases in the warm season to 35 ° C, in the cold - to 38 ° C. The duration of milk digestion with the accelerated method is 4.0-4.5 hours, i.e., reduced by 2.0-3.5 hours, while the release of whey from the clot is more intense.

To improve the quality of curd, it is desirable to use a non-stop method for preparing starter on sterilized milk, which allows reducing the dose of starter application to 0.8-1.0% with guaranteed purity.

In a rennet-acid method of producing cottage cheese, after adding starter, a 40% solution of calcium chloride (at a rate of 400 g of anhydrous salt per 1 ton of milk) prepared on boiled and cooled to 40-45 ° C water is added. Calcium chloride restores the ability of pasteurized milk to form a dense, well-separating clot under the influence of rennet enzyme. Immediately after that rennet enzyme or pepsin is added to milk in the form of 1% solution at the rate of 1 g per 1 t of milk. Rennet enzyme is dissolved in boiled and cooled to 35 ° C water. Pepsin solution in order to increase its activity is prepared on acidic clarified serum 5-8 hours before use. To accelerate curd bath 6 turnover, milk is bored to acidity 32-35 ° T in tanks, and then pumped to curd baths and calcium chloride and enzyme are added.

The end of the ripening and the readiness of the clot are determined by its acidity (for fatty and bold cottage cheese it should be 58-60 ° T, for low-fat - 66-70 ° T) and visually - the clot should be dense, give smooth smooth edges on the fracture with the release of transparent greenish serum. Digestion under the acid method lasts 6-8 hours, rennet - 4-6 hours, using an active acid-forming starter - 3-4 hours.

To accelerate the release of serum, the finished clot is cut with special wire knives into cubes with a face size of 2 cm. With the acid method, the cut clot is heated to 36-38 ° C to intensify the release of serum and held for 15-20 minutes, after which it is removed. With rennic acid, the cut clot is left alone for 40-60 minutes without heating for intensive serum isolation.

2.1.5 Pressing and cooling

For further separation of serum, the clot is subjected to self-pressing and pressing. To do this, it is poured into brave or lavsan bags of 7-9 kg (70% of the capacity of the bag), they are tied and placed in several rows in a press trolley. Under the influence of its own mass, serum is released from the clot. Self-pressing takes place in the workshop at temperature not higher than 16 ° С and lasts for not less than 1 h. The end of self-compression is determined visually by the surface of the clot, which loses its gloss and becomes matte. Then cottage cheese is pressed under pressure until ready. In the process of pressing, the curd bags are shaken several times and transferred. To avoid acidity increase, pressing must be carried out in rooms with air temperature of 3-6 ° С, and upon its completion immediately direct curd for cooling to temperature not higher than 8 ° С

2.1.6 Bottling, packing

The finished product is packed on machines in small and large containers. Curd is packed into cardboard boxes with inserts made of parchment and polyethylene film. Cottage cheese is packed into a small package in the form of bars weighing 0.25; 0.5 and 1 kg wrapped in parchment or cellophane, as well as in cardboard boxes, bags, cups made of various polymeric materials .

2.1.7 Marking, storage

Cottage cheese is stored in cooling chambers for not more than 36 hours at chamber temperature not higher than 8 ° C and humidity 80-85 %.

Energy saving

5.1. Problem setting

Decree of the Government of the Russian Federation of December 19, 2012 No. 270 - Federal Law. "On energy conservation and on improving energy efficiency and on amending certain legislative acts of the Russian Federation," the goal was set to reduce the energy intensity of Russian economic sectors by transferring the Russian economy to an energy-saving development path due to the full use of energy-saving technologies and equipment, while reducing the negative impact on the environment of both fuel and energy facilities and energy-consuming industries.

This diploma project considers some energy-saving measures in relation to the production of cottage cheese.

5.2. Analysis of the existing situation

The main resources consumed during the maturation of cottage cheese are electricity and heating steam.

Previously, a curd bath VTN2.5 was used to make cottage cheese, in order to maintain a given temperature, hot water generated in a dairy boiler was used. This technology is quite energy intensive, thermal energy consumption is 386 Gcal

5.4 Additional Energy Conservation Activities

Additional measures are needed to improve energy efficiency.

Such measures include, for example, the use of alternative energy sources, capacitor plants, frequency-controlled electric drives, smooth starters with an energy saving function. For example, the installation of a smooth starter for curd pump equipment will save about 30% of the electricity consumed.

5.5 Conclusions on "Energy Saving" Section

Use of the proposed curd bath with mixing device is effective from the point of view of energy saving, as it allows to reduce specific energy consumption for curd production.

The annual volume of energy (thermal energy) savings will be 128.05 Gcal due to the new version, and 74653.15 rubles in cash form.

The annual volume of electricity consumption through the use of the new option will be 3285 kWh/year, and in cash form 7949.7 rubles.

The total energy savings, taking into account electricity costs, in monetary form will amount to 6,6685.45 rubles.

Project Feasibility Study Section

6.1 Production Flow Chart Improvement

cottage cheese

The project proposes an improvement of the technological scheme for the production of cottage cheese at the stage of its ripening. To do this, it is provided to replace the following equipment: cottage cheese maturation baths with more progressive ones with mixing devices. Implementation of measures will reduce the number of workers by 4 people, significantly improve working conditions, reduce heat consumption from 0.04 to 0.02 Gcal per 1 kg of cottage cheese.

6.2 Production capacity

The production capacity in the design version is increasing, the output in the design version will be 53.6 tons per year, and in the base version it will be 41.3 tons per year.

Conclusion

In this diploma project, a schematic diagram of the manufacture of cottage cheese was considered, and the modernization of the curd bath by installing a stirring device was also proposed. In this regard, the annual profit will be 2915800 rubles, the payback period of additional capital investments is 0.7 years.

The area of ​ ​ possible application: the production of cottage cheese in the classic "open" way, the production of other products using similar technology.