DAIRY PLANT DESIGN AND LAYOUT

Module 3. Planning and principle of dairy plant layout

Lesson 11
DAIRY BUILDING PLANNING

11.1 Introduction

The planning of dairy building is the main activities for establishment of dairy plant. Planning is the way of proceeding or scheme of arrangement for executing any work or project. Designing a dairy plant layout is a joint venture of Architects, Dairy Managers, Dairy Engineers and Administrators. It is necessary to consider all technical aspects and economical considerations. The ideas of several technocrats are sought and based on the suggestions of all concerned, actual building planning is worked out. The requirement of utilities such as water, refrigeration, steam, electricity etc. is carefully estimated while planning a dairy. The planning of dairy building depends on capacity, product mix, size of equipments, work space to be kept, future expansion requirement etc. There is no any blue print to be used for design of dairy building. It varies from plant to plant even though the capacity and product mix is the same.

11.2 Dairy Plant Layout

The main objective of dairy plant layout is to design the dairy plant to carry out all dairy processing operations. The knowledge of estimating the requirement of various equipments, location of equipments in different sections, space requirement for equipment and the general civil aspects of building construction. The engineer should have very clear and complete understanding of requirement and management policies. The management policies decide the future expansion requirement of a dairy plant. Management decision with respect to the addition of new of products is important to be considered at the stage of dairy plant layout. It also includes process schedule to be followed and requirement of different utilities.

A well designed layout must facilitate production operations, minimize material handling maintain flexibility of the operation for alteration and expansion, minimize investment in equipment, make economical use of floor area, promote effective utilization of the labour and provide for employee convenience and comfort.

It is up-most important to design optimum size of dairy building. Some enterpriser engages an architect to prepare the plant layout for an attractive design and consult dairy equipment manufacturers for ideas regarding latest machinery. However, involvement of dairy engineer in the layout is very vital to take care of all necessary requirements. It is advisable to make judicial use of land available and optimum cost in construction of building.

11.3 Important Factors for Planning of Dairy Building

The following are the basic factors which must be considered before planning the dairy building.

• Milk handling capacity and variation in milk handled every day.
• Method of milk collection and transportation
• Design of milk processing section.
• Method of milk packaging.
• Way of milk distribution to consumers
• Source of electric power supply, water supply and waste water disposal.
• Type of fuel for boiler.
• Provision for subsequent future expansion.
• Transportation facilities and conditions of road

The source of water throughout the year is very important in design of the plant. Water may be distributed by gravity system or hydro-flow system using G.I. pipelines. If power shut down is frequent, then provision should be made for standby availability of electric power. It may not be possible for large plant to have diesel electric power generator for total load of the plant. But partial requirement of electrical power generator facilities is necessary to carry out essential low power consuming operations. The method of effluent treatment system is to be considered at the design stage of the building and provision is made for disposal of treated water.

11.4 Planning of Dairy Processing Schedule

Process scheduling means arranging the flow of products through various operations in the plant in order to achieve maximum use equipment and labour, and the processing of the products is accomplished in the shortest possible time with minimum delays between processing of different products.

11.5 Operational Layouts

Operational layouts describe operations which take place in processing or manufacture of different products. All operations involved are represented diagrammatically in chronological way (sequence-wise flow diagram) which can be easily understood by a layman. Even operational layouts can be shown in pictorial views or three dimensional layouts. Such layouts would help to understand the sequence of operations to be followed for the manufacture of various products.

11.6 Principles of Dairy Layout

A dairy plan engineer should try to incorporate all the fundamental aspects listed below. This would help in performing dairy activities economically and efficiently.

1. The milk path should be as short as possible. This will minimize the cost of pipeline and cleaning time.

2. Reception and dispatch must be arranged in such a way that congestion of transport vehicles is avoided.

3. As general guidelines, a small dairy may have reception and dispatch on one dock but it is necessary to have them separate for large dairy plants.

4. Where space is available, single storey building is most suited. The plan may have a rectangular shape with roads on all sides.

5. Location of milk silo outside the building area may save space and construction cost. This is widely followed in almost all dairy plants.

6. As far as possible refrigeration and boiler section are kept little away on the side of the building on ground floor. Refrigeration machinery room should be near the process room and cold store to reduce the piping cost and pressure drop.

7. Laboratory should have easy approach to reception room and processing room.

8. Separate building block for administrative offices

11.7 Product Storage

There are two types of storage rooms required for dairy plants.

• Products stored at room temperature e.g. milk powder
• Products stored at lower temperature e.g. milk, butter, ice-cream, cheese etc.

The design of cold storages requires careful planning to store the product at lower temperature. Pasteurized milk is stored at 3-4 ⁰ C while ice-cream is stored at – 25 ⁰ C. Therefore, separate cold storages are required for different dairy products. The capacity of cold storage and cooling load calculations are necessary for the design of the cold storages. The frequency of dispatch and period of storage required are essentially required for design of the cold storages.

11.8 Selection of Equipment

The selection of equipments before the actual design of building is necessary to decide the space and input required for these equipments. Some equipments are very large which are required to be installed before the construction of walls of the building. The distance to be kept between the equipments is also important to decide the ease of opening the equipment for maintenance purpose. Specifications of each equipment is necessary to be decided at the time of planning of dairy building.