Integrated Paper Mill

Production process of papermaking from raw material (trees/wood handling) to paper product known as the integrated mill. The process can be batch or continuous form.

While the factory which processing wood into pulp alone or pulp into paper, process known as unintegrated mills.

Countries that have forest resources chose build an integrated mills because of the availability of raw materials and economic considerations. For a country that only has the technology, human resources and water, make a paper mill to facilitate the distribution and participate in paper markets.

The integrated paper mill overview:

Integrated Mills

The process of papermaking uses raw materials; water, energy (steam and power supply), chemicals and wood 
(1) Trees(that contain cellulose/fiber). (2) Boilers  produce steam for heating process or to drive turbines (3) that make power supply for motor and instrumentation devices. Harvesting woods comes to pulp mills as chips (4) or as logs (5) which are debarkered (6) and then send into a chipper. Chips (7) and chemicals conveyed into a Digester (8). After cooking with chemical and steam chips separated into fiber and lignin. Then the mixture is blown out of the pressurized digester into a blow tank (9). Washer (10) clean the mixture by removing the cooking chemicals and lignin, turning and lignin(black liquor) into pulp. The black liquor pumped into evaporator (11) which remove water. the concentrated black liquor is pumped into recovery boiler (12) Lime is added in the caustizier (13) from a lime kiln (14) and the chemicals are pumped to a clarifier (15) to allow the solids to settle. The naturally brown pulp is made white through a bleaching process (16) The pulp fibers are then prepared for the paper machine in refiners (17) Recovered paper (18)is often used for additional fiber. This fiber stock is pulped (19) and cleaned (20), (21) to ensure a uniform sheet of paper.

To make paper 1% stock consistency flows from the headbox (22) into a sheet former (23) a wire screen that drains some of the water into a wire pit (24). the formed sheet carried into press section (25) to remove more water. The paper presses over dryers (26) enclosed in a hood (27) Specialty papers get coated with liquid clay or chemicals in a coating machine (28), to improve the surface and printability of the paper. The calender (29)smoothes the paper then wound on a reel (30). The reel is either cut into smaller rolls on a slitter (31) or made into sheets of paper on a sheeter (32). The finished product then shipped to customers arround the world.