Process Flowchart

October 29, 2017 | Author: Marianne Salinas Meneses | Category: Pulp (Paper), Paper, Recycling, Biodegradable Materials, Industrial Processes
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TIPCO manufactures newsprint and printing / writing paper using 100% recycled paper as raw materials. About 80% of wastepaper requirements are imported from the United States of America, Europe, Hong Kong, Japan and Australia.  RAW MATERIALS DEPARTMENT Raw Materials Department processes imported and locally sourced recovered paper by sorting, conveying them into pulpers and converting them into fibrous, cellulose mass. Waste paper is collected from Waste Paper Banks and Commercial collections. When you deposit your used papers into a waste paper bank, you are sorting the paper into grades before the merchant collects it. This is why you can only put certain papers into a particular bank. Many offices have in place an office recycling scheme. Again the waste paper is usually segregated ready to be collected. The waste paper merchant collects the used paper which is then sorted by hand into different

grades. Paper not suitable for recycling is removed. The waste paper merchant will then bale the waste paper ready to be taken to the paper mill.  STOCK PREPARATION DEPARTMENT



PULPING AND SLUSHING

The stock preparation stage involves the preparation of fibrous raw materials which normally are secondary raw materials consisting of recycled corrugated cartons, paper and the like. These are fed into a hydra pulper and are repulped to achieve a 5-6% consistency of the mixture, after which it is further processed through a waste processing plant to clean, screen, and remove contaminants such as plastics, adhesives, sand, ink, etc. 

CLEANING

. Before printed paper, such as office waste and newspapers, can be recycled the ink needs to be removed, otherwise it will be dispersed into the pulp and a dull grey paper would result. There are two main processes for de-inking waste paper - these are known as washing and flotation. Washing The waste paper is placed into a pulper with large quantities of water and broken down into slurry. Contraries -such as staples - are removed using centrifugal screens. Most of the water containing the dispersed ink is drained through slots or screens that allow the dispersed ink particles through, without taking the pulp.

Flotation Again the waste is made into slurry and contaminants removed. Special surfactant chemicals are added which makes a sticky froth on the top of the pulp. Air bubbles are blown through the pulp and these carry the inks to the surface. As the bubbles reach the top a foam layer is formed that traps the ink. The foam must be removed before the bubbles break or the ink will go back into the pulp. Because the ink is removed from the flotation machine in a concentrated form, the flotation system does not require a large water treatment plant.



SCREENING

After cleaning the secondary feed stock, the fibre is passed through hot dispersion to dissolve uniformly the micro stickies and pitches that are not removed in the system creating a cleaner stock. 

THICKENING

It is then passed through a series of deflakers and disk refiners to develop the required strength properties of the paper. 

REFINING

The refined pulp is then metered and fed onto the paper machine. The blend of pulp and chemicals is then passed through a final screen wherein residual contaminants are further removed before being pumped into a pressurized headbox.

 SHEET FORMATION DEPARTMENT

The refined pulp is then spread uniformly across the width of the paper machine against a continuously moving wire. As the water from the material on the wire drains, a fibre mat is formed, thus, the formed sheet will eventually become the finished product.



PRESSING

The fibre mats are dried passing through a computer controlled mechanical press. The process controls and optimizes the moisture content of the sheet passing through the press section. The moisture content after passing through the press is reduced by up to 50%.



DRYING

The press sheet then passes through a series of steam heated cylinder dryers where the moisture content is further reduced to about 7%.



CALENDERING

As part of the drying process, the next step is calendering. This is done to achieve uniform caliper and glossy finish. It is through this process that the smoothness requirement is attained.

 WINDER DEPARTMENT 

REWINDING

The final stage in the paper-making process of liner board is rewinding. In this stage, the full width of the paper exiting the paper machine is cut and wound according to the consumer specifications/requirements.

The final product weighs from 0.85 – 1.5 MT per roll. The finished rolls are sampled, weighed, inspected and tested for various physical properties in the plant’s laboratory. If the finished product passes the required specifications, the rolls are transferred to the finished goods warehouse and scheduled for delivery.

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