General Process Description

Pulp & Paper Manufacturing Agro-Pulping


The agro-wastes such as bagasse etc. are received from nearby area. The raw material contains pith, dust and fins etc. which are considered non-process elements. These are removed by dry-depithing or dry de-dusting before being fed into washing section. The pith so obtained from the dry depithing are fired in boiler as it has a good calorific value in washing section, The raw material is passed through pulper/ drum washer. The raw material is washed only with the available backwater from the process sections. Due to vigorous Agitation in the pulper, the other non-process elements are also removed. Some part of free water is carried along with the raw material which is then fed into aqua-separator. The aqua-separator helps in removing the excess water from raw material .

Chlorine Di-Oxide Preparation

The sodium chlorate (NaCLO3) is imported in safe HDPE bags. The sodium chlorate is allowed to react in two—stage reactor system with hydrogen peroxide in strong sulphuric acid solution to produce CLO2. The reaction by-products are oxygen & waste acid containing sodium bi-sulphate. The main advantages of this system are lower capital cost, chlorine free product, high yield of CLO2, reduced pollution load on mill effluent. .

Environment- Friendly Bleaching Process

CLO2 - Oxidative - CLO2 (D0 — OX — D1 STCIQGS) D0 Stage - Bleaching with Chlorine di-oxide OX - Oxidative bleaching. D1 Stage — Bleaching with chlorine di-oxide The unbleached pulp is subject to bleaching by Chlorine di-oxide - Oxidative bleaching with oxybleach — Chlorine Di-oxide (D0- OX- D1) sequence. The sequence is adopted so that the AOX levels are retained within the permissible limits. The chlorine (CLO2) is added in first stage to loosen the Lignin from the cellulose fiber. Oxidative bleaching is used in intermediate stage. The chlorine di-oxide is added in the 3rd stage of bleaching to achieve the desired brightness level of 85-86% ISO. The main advantages of adopting this bleaching sequence are — .

  • Reduction in BOD, COD & AOX in bleaching plant effluent by 30-35%. /li>
  • The oxidative bleaching selectivity removes residual lignin from the fiber and facilitates bleaching with less pollution load.
  • Gain in concentration of black liquor resulting better run ability of chemical recovery plant.
  • Improvement in pulp quality, i.e., gain in brightness, viscosity & strength properties.

Wood Pulping/ Broke Pulping -

The imported soft wood pulp and broke obtained from manufactured paper is subject to mixing & slushing with water in separate pulpers. The wood pulp/ broke street is then cleaned in vibrating screen to remove unwanted material contained in them. Then the pulp is passed through high density cleaners to remove dirt particles. The cleaned pulp is then mixed with the bleached agro-pulp in certain required proportion. .

Filler (GCC)

GCC is added to pulp which works as filler and improves properties of paper. GCC is available in powder form and it is mixed with water and the solution so obtained is processed through vibrating screens to remove the undesired particles from it. .

Paper Machine

The pulp is then pumped into machine chest and then to approach flow system containing of fan pump, centricleaner and pressure screen. The final clean pulp goes to paper machine head box which spreads the fiber uniformly across the synthetic forming fabric. From head box, the fiber passed over fourdrinier table where approx. 50% of total water is removed from the pulp. .

The pulp now is in sheet form and contains some amount of free water. The sheet is then pressed into series of presses to remove the free water from it. The paper sheet is then passed into series of steam heated driers so that the inherent moisture from paper fiber is removed. .


The use of environment-friendly techniques and eco-friendly products in pulp & paper manufacturing gives a whole new dimension to the industry. Today, as the population increases at rapid rate, the demand for paper increases too. To feed this demand, the forest based raw materials are becoming scarce. So the industry & research institutions are searching new products for preparation of Pulp & paper. Bindals Papers Mills Limited is one such industry that is using eco-friendly technology to manufacture the paper and has earned a good name in the market by producing quality paper using the agro-based raw materials. In present scenario Bindals has adopted a big effort to save earth and our rivers by adoption of ZLD technology in mill. Bindals is first mill globally to achieve such practices among agro based integrated pulp & paper mill. The management is eager to introduce new concepts in development of new products by using safe & sound technologies that also pose no danger to the environment & natural resources by keeping itself sustained in the market. Use of enzymes is one such approach in which the industry is keen to venture further to reduce the production cost and to develop clean & green products. .