Drum Dryer Calculation - Drawings

Project Description

This course work was carried out in the discipline of construction materials technology. It considers the basic principles of the theory of heat and mass exchange, gives a technological scheme for the production of wood chip boards (chipboards), its detailed description. The equipment, namely the drum dryer, is calculated.

A graphic part consisting of a drum dryer diagram and a process diagram for the production of CPD is also performed.

Introduction

The final product in this course work is wood chip boards (chipboards). Currently, particle boards are the most popular material. The main advantages of CPD are low cost and ease of processing.

DSP is made from pressed coarse wood chips with addition of thermosetting synthetic resin as binding agent.

A feature of the production of particle boards is the use of carbamide-formaldehyde oligomers as binders, which have a significant raw material base and a relatively low cost compared to other condensation resins.

Particle boards based on a carbamide-formaldehyde binder are widely used in the production of furniture and for the internal skin of houses. Therefore, the focus is on carbamide-formaldehyde resins, the most common binder for chip boards.

For making particle boards that can be widely used in construction, it is most effective to use binders that give the plates increased water and weatherability. These include phenol-formaldehyde resins, which, despite known disadvantages (toxicity, long-term curing, higher cost), are used abroad for the production of particle boards of increased atmospheric resistance.

Purpose of plates. They produce general-purpose, for construction, special-purpose plates. General purpose plates are not subject to high requirements for water and bio-resistance. Features of general-purpose slabs (including for furniture production) are the average level of strength and water resistance, low toxicity and in most cases high surface quality.

Such slabs are designed for operation under conditions that exclude exposure to water, moisture, high temperature, etc., for example, inside heated rooms.

General-purpose slabs are usually used for the manufacture of piece and built-in furniture, for interior decoration, inside the building, etc. Such boards are preferably made on the basis of carbamide-formaldehyde resins without introducing special additives into the chip mass.

Construction slabs shall have high strength, water and bioavailability, and in some cases fire resistance, good heat and sound insulation properties, etc. Such boards are mainly made on the basis of phenol-formaldehyde resins and inorganic binders (Portland cement, caustic magnesite, etc.); and in some cases on the basis of carbamide-formaldehyde resins with the introduction of special additives (hydrophobizers and antiseptics) into the chip mass.

Special purpose slabs shall have special properties, for example, with regard to dimensions, density, strength in a certain direction, water, bio-, fire resistance, etc. Such plates are made according to special orders.

Scope. Today, CPD is the most common material for interior design, construction (roofs, partitions, even floors), especially in the production of furniture. The undeniable advantages of CPD are ease of processing and cost-effectiveness. CPD products have an attractive appearance, ease of use and much lower cost compared to similar wood-array products.

In its pure form, that is, without special coating, CPD is used only in construction. For use in furniture production, the DSP has a decorative coating of films, veneer, laminate (paper-layered plastic) and varnish.

Areas of CPD application:

Site Fencing Panels

Garden houses

Interior improved decoration of buildings and cottages built according to individual design (arches, suspended ceilings, partitions, wall decoration)

Sports grounds, auditoriums

Stands and structures of exhibition halls

Road signs, billboards and fences

Room doors, lining of large doors

Internal partitions, wall and ceiling panels, rough floors

Case and soft furniture

Furniture profile and furniture facades

Furniture for offices, hallways, computer and writing tables, school furniture

Osmoleniye

The production of ground chips occurs in continuous mixers, in which the binder is sprayed through a series of nozzles, each connected to a dosing pump. Ground chips with the help of a screw shaft advance to another zone, where they are mixed with blades. Example: SM7 mixer.

This is the most difficult and important step, since the manufacturing technology requires each chip to be coated with a binder. Non-ground chips do not glue together, and excessive resin on chips leads to overspending of the binder and poor quality of the boards. The binder is fed into the mixer as solutions. Their concentration in the stream of the outer layer 53 is 55%, the inner layer is slightly higher (60-61%).

Barabannaya_sushilka.dwg