synthesis gas plant producing bioliquids integrated to pulp and paper

How to make excercise books

The production process begins by conveying an endless ribbon of paper via unwinding unit into a printing and ruling machine. The paper is lined there, if necessary, according to the use (as writing or as an arithmetic book). Then the endless ribbon is cut into sheet layers by means of a rotary cross cutter, according to the width of the envisaged book. These sheet layers are counted and stacked.

How to make egg tray from waste paper

This post  is one in a series of posts on paper like how to make re-pulped paper, paper from straw and small scale paper.

Raw Materials

To make egg trays from waste paper, the following materials are required. Waste paper, caustic soda and other fibrous materials are the main raw materials. 

The waste paper is beaten with a stick and any dust and other undesired materials are   removed. Then the  waste paper is cut in to pieces using a cutting machine which can be  operated either manually or electrically. 

The cut pieces are transferred to a beater and water is added and then the beater is set in 

Toilet paper production process

Broadly speaking, there are two methods for processing waste paper, namely, continuous and batch systems. The batch process is recommended for this plant for the daily production capacity of the mill is very small.

The manufacturing process begins when waste paper is moved up to the sorting yard above the digester by elevator. The sorted waste paper is fed into the global digester. Simultaneously with the feeding, sodium sulphite, soda ash, etc. are sprinkled thoroughly over the waste paper. After stuffing of the digester has been completed, the gut for the digester is tightly closed. Steam is blown into the digester as it is rotated. 

The next step is the charging of the material into the blow poacher. Circulation is performed

Paper tubes, spools and drums making process

Paper tubes or cones, spools and drums are widely used as packages, shipping containers and component parts. These products are commonly used in the textile factories for winding threads and yarns as well as to form rolls of woven cloth or fabric (which in the later case the paper tubes are usually called bobbins). Also paper tubes are needed in plastic factories that produce poly films, sheets and woven fabrics. Paper factories as well require paper tubes for winding products such as toilet tissues and related items.

Kraft paper reel is unwounded and punched out into fan shape for paper cones and rectangular shape for paper tubes. After beveling and

Small scale Paper Making Process

The process of making paper is based on the fact that wet cellulose fibers bind together when dried under restraint. The processing of paper usually involves the initial separation of the cellulose fibers to form a wet pulp, some form of treatment, such as beating and refining, while in the pulped state, to enhance the quality of the final product, then forming of the sheet paper by hand molding or by paper making machine, and drying.

Some further processing is often carried out before or during drying to acquire the desired finish.

Flow sheet of pulp and paper making process

Raw Materials

Sources of fiber include straw from wheat, barley or rice, bagasse, maize stalks, bamboo, cotton cuttings, lint and fluff, rags (from cotton material), hemp and sisal from old ropes and jute. chemicals required are NaOH, Chlorine and CaO.

The stages involved in transforming raw materials

Re-pulped paper production process

Re-pulped paper is suitable for drawing paper, permanent document paper, filter papers, pads, file covers, duplicating papers, tissue papers, etc. The paper has high tensile bursting, tearing and double fold strength as compared to mill made paper and it does not turn to brittle due to aging. Re-pulped paper has good texture for drawing and writing.

Production of re-pulped paper involves these main steps;

1. Preliminary Treatment

This stage requires cutting of the cotton rags into small bits with power operated rag choppers. In the case of agro fibers, the material, after chopping, is cooked in a small open digester with low percentage of alkali.

2. Beating

Next, the cut and dusted rags are beaten to pulp stock in small power operated Hollander beater, with or without bleaching. Then the material is washed by means of a washer drum followed by further beating. Addition of natural fillers /loadings and dyeing and sitting chemicals as required for the end product is also accomplished during beating.

3. Sheet Formation, Peeling and Drying

Sheet formation is carried out by draining water from a dilute fiber mix through a fine screen and both dry the mat thus formed by dewatering with rollers. Then drying on heated rolls and smoothing with calendars is conducted. The calendared papers is hand sorted, edges trimmed with the help of power operated cutting machine and packed in suitable packets.

The alternative technology of producing re pulped paper is producing coated paper.

Coated paper has a thin layer of material such as china clay applied to one or both sides in order to create a surface more suitable for high-resolution halftone screens that have the highest optical density in the printed image. Coating requires additional machinery investment. Thus, this option is not recommended since the envisaged plant can sell its output to producers of tissue paper, pads etc .

Straw pulp and yellow board making process

The manufacture of yellow board has two major stages. The first stage is pulp making and the second is paper or board making. The detail of the production process is presented below.

Business plan of Straw pulp

Stage I: Pulp Making

1. Pretreatment of Straw and Cooking

A. Pretreatment of Straw: The wheat straw, which has been collected and stored, is cut to a suitable uniform length by a cutter, and it is sent to the duster via a belt conveyor. The dusted straw is carried to the next process on another conveyor.

B. Cooking: The straw stored in a chip bin is put in a digester at the rate of about 2.5 tons of dry straw at a time. When the above operation is over, a fixed amount of lime solution is added, after which digestion continues for several hours (6-8 h/cycle) with steam under a pressure of 4-6 kg/cm². The cooked material is blown into a blow pit, and waste liquid is washed away by a beater placed in the lower part of the pit.

2. Stock Preparation

The raw material made available from the above operation is fed into a dilution box with a pump. Fresh water is added to the box to provide consistency to suit the following beating process. Nodes and sheaves are eliminated by the inclined screen to drop the stock into the next beater, in which it is treated for an appropriate number of hours so as to make it suitable for paper machining, as well as to provide a good quality for the finished paper. Stock which has been subjected to the beater process is stored in the beater chest, out of which it is sent into the head box by the pump. The stock goes out of the above equipment into the selective screen, where is dusted, for transfer to the distributing box and head box.

3. Chemical Preparation

This is an independent section, in which the lime for digestion is dissolved to the stipulated concentration and stored. The process so far described constitutes the first half of the paper making process, namely the section for the manufacturing of raw materials.

Stage II: Paper Making

1. Paper machine- Wire, Press and Dryer Part

A. Wire Part: One or several cylinder moulds rotate in each vat. The stock which has been fed is scooped up by the rotating cylinder mould machine for formation of sheet. When cylinders go out of the stock liquid, the surfaces of the cylinders are covered with wet paper which constitutes fabrique. The number of cylinders is decided according to the thickness of paper to be made.

B. Press part: The bottom felts, which rotate endlessly, pass the crests of the cylinders one by one to pick up the paper layer formed there. After passage of the second press roll, felt and paper are separated, with felt resuming its advance to the cylinder after water has been squeezed out of the felt by the squeeze roll, and paper proceeding towards the next dryer part.

C. Dryer part: The paper which comes out of the final press roll has both smoothed by the smoother. It is dried when it comes into contact with the surfaces of the fourteen paper dryers (cylindrical, with steam inside), one after another. Canvass or dry felt is employed to insure good contact with cylinders.

2. Calendar

The calendar comprises for chilled rolls, the surfaces of which are hardened. Paper gains glaze as it passes between the rolls through the slip action of heat and pressure.

3. Cutter

Paper is finally cut into the required size by the cutter, thereby ending the continuous paper making process. When paper is specially required in a smaller size, it is cut by a guillotine cutter which is provided separately.

The alternative technological option refers to the use of manual labor in the drying process. In this method a blotter sheet is used to collect the water instead of canvass or dry felt. Then, the paper is hanged in open space and is left for a while until the moisture level is reduced to a level less than 6 percent. Although this option has the advantage of lower cost when compared to steam-heated dryer discussed earlier, it is not recommended for a scale and quality of production envisaged by the proposed plant.

Production of Paper from straw

The basic process of making paper from straw involves two stages: The first stage is the breaking up of wheat straw in water to form a pulp (i.e. a suspension of fibers). In this stage the wheat straw is first cut and then cooked. This is followed by some form of treatment, such as beating and refining, to enhance the quality of the final product. Before paper making is conducted, stock and chemical preparation is made. The second stage represents the formation of sheet paper. This involves formation of sheet in the mould, pressing and drying often under pressure. Finally paper is cut into the required size by the cutter machine.

The alternative production technology makes use of a process that involves the use of manual labor in the washing, pulping and the formation of sheet in the mould. Although this approach requires lower investment, it is used in a less standard and low volume production and hence is not suitable for the quality product proposed by the envisaged plant.