Process Modifications For New Products Innovation

 

The history of paper making goes back thousands of years. This is because humans have a need to communicate and record their thoughts or ideas, thus encouraging creating media for that purpose. Starting from very simple media such as stones, bones, plant leaves, animal skins, to sheets of paper as we encounter today. Even the word paper which in English comes from the word papyrus, which is a type of reed plant that grows on the banks of rivers. The ancestors of the Egyptians found paper-like material from these papyrus, even for about 4000 years Egypt monopolized the production of these papyrus. This is mainly because papyrus only thrives on the periphery of the Nile in Egypt. The raw materials, production techniques and quality of the paper produced are constantly changing according to technological advances and available raw materials. The discovery of the first paper recorded in China around 100 AD and then spread to the Arabian peninsula. Meanwhile Arab Muslims in the eighth century AD brought their paper and manufacturing techniques to the Mediterranean region and by the end of the eighth century the paper had been produced in Baghdad, the capital of the Abbasid caliphate in central Iraq. This made the paper-making technique spread throughout his territory. It particularly spread to the Mediterranean region and replaced the papyrus and parchment (of sheepskin or goat's skin) that had dominated for millennia. Meanwhile, Christian Europe only began to learn to make paper in the twelfth century.

The unavailability of raw materials such as in China makes paper production in Arabia using used clothes that are not used, as well as the development of production techniques. Paper making at that time was very dependent on the supply of clean water. This is because only water was used to bleach the fibers before the discovery of chlorine in the eighteenth century, which was further sun dried to obtain white paper. This condition continued in mainland Europe so that production techniques and quality of paper improved. Even the invention of the printing press by Johann Gutenberg in 1436 made it easier to produce books faster and cheaper. This era also marked the acceleration of this new civilization because the culture of reading books had increased rapidly so that the need for paper also increased by itself. The use of chemicals for paper production began around 1800, namely wood that has been crushed and then "digested" with chemicals including the use of sulfates. Paper is able to give a boost from an oral culture to a written culture and the development of a number of notation systems such as language, mathematics, commercial transactions, architectural drafting, chemical formulas, which are the product of a number of inventions and the distribution of printed books. In short, the paper has marked the "new era of civilization" as we are experiencing today.

The production of pulp is basically releasing cellulose and hemicellulose fibers from lignin with certain chemicals. During the cellulose extraction process, the extractive material is also separated. The cellulose and hemicellulose fibers are also kept intact, thereby increasing the yield of the usable fibers. The fibers produced are naturally colored according to the type of raw material and must be bleached before they can be used for paper. In the bleaching process, efforts must be made in such a way so that the cellulose fibers are not damaged, including the use of selective chemicals for the bleaching agent. Cellulose is the main organic material in woody plants. When processed into paper, it can become a variety of paper products. After the cellulose fibers are separated or released from the binder, namely lignin, so that they become pulp, the pulp is then glued back to form paper with a certain adhesive. Softwood is the raw material that is mostly used for the production of this pulp because its cellulose fibers are longer (about 3–4 mm in length with a diameter of 25–30 micro). The low lignin content of hardwoods is used for the production of specialty paper where smoothness and softness are desired.

There are a number of processes and a variety of basic processes that can be used for the production of pulp from wood. The main processes used by the paper industry are kraft process (commonly known as sulfate process), thermochemical process, semi-chemical process and sulfite process. The kraft process is still the most popular and most widely used today or mainstream in the paper production process. The analogy, this is like the use of a limestone scrubber in the exhaust gas treatment of power plants, especially coal power plants, more details can be read here. The advantages of the kraft process compared to other processes are high cellulose yield and recovery liquor, so that the process becomes efficient or low production costs. The paper production process begins with the use of wood with a diameter of 8 cm up, then the wood is peeled off (debarking). The debarking process can be done mechanically or with high pressure water at 1400 psi perpendicular to the log.

Blu Karb Carbonisation

 Paper mills are always supported by extensive timber plantations as a source of raw materials, such as plantations or acacia forests. Timber less than 8 cm in diameter or in the range of 5-8 cm can be used for charcoal production. With proven carbonization technology and a semi-continuous process capacity of 3000 tons / year with charcoal quality exceeding European standards (fixed caron> 82%) can be achieved, for more details can be read here. Meanwhile, wood in the form of smaller branches can also be used for the production of briquettes or pellets. Briquettes are technically easier and cheaper to produce, read more details here. In this way, the wood wastes can be utilized optimally or even zero waste.

 

After debarking the large wood, the wood was then reduced in size into chips. The wood chips are then put into a digester (pressure vessel) with a capacity of 1500-3600 cubic feet and added recovered cooking liquor. After the digestion process in the digester (pressure vessel) is complete, the pressure is lowered to 80 PSI and the contents are poured into the tank. Furthermore, the pulp is filtered and further processed as in the diagram above so that it becomes the final product in the form of paper.

Then what if the kraft process is reversed? In the kraft process what occurs is the cellulose fibers are separated from the lignin and kept intact or cellulose becomes the main product. When the process is reversed it means that lignin is separated from cellulose and kept intact or lignin becomes the main product. This means that the lignin produced from the kraft process is different from the lignin from the reverse process in quality, likewise the cellulose produced from the kraft process will also have different qualities from the reverse process. Why is it necessary to reverse the kraft process? What is the goal and is it profitable? Of course the main reason is to create new, more profitable businesses. This product diversification is projected to have better market and economic opportunities in the future than paper products. The products produced from this process are cellulose sugar and lignin from these trees.

Cellulose sugar comes from non-food biomass (eg wood and agricultural wastes). Biomass mainly consists of cellulosic carbohydrate polymers, hemicellulose, and aromatic polymers (lignin). Hemicellulose is a polymer consisting mostly of the five-carbon sugar C 5 H 10 O 5 (xylose) and cellulose is a polymer of C 6 H 12 O 6 (glucose) six-carbon sugar. Cellulose is the most common organic compound on Earth. About 33% of all plant matter is cellulose (the cellulose content of cotton is 90% and that of wood is 40-50%). Cellulose cannot be digested by humans, it can only be digested by animals that have the enzyme cellulose. Cellulose fibers are considered the structural building blocks of plants and are tightly bound to lignin, but biomass can be deconstructed using acid hydrolysis, enzymatic hydrolysis, organosolv dissolution, autohydrolysis or supercritical hydrolysis. 

 

 

Enzymatic Hidrolysis Process

When the C5 and C6 sugars are produced using enzymatic hydrolysis, the enzymes must be able to chew the cellulose easily and convert them into C5 and C6 sugars and then separate these sugars from lignin. So that the output that comes out of the process unit has two main streams, namely sugar and lignin. The molecular structure of the lignin produced is also closer to that of the tree than the lignin produced from the kraft process. The resulting lignin can also be used in resin production, there is even a great potential for the use of lignin and sugar to create feed additives in livestock.

The production of cellulose sugar at low cost and large capacity has also been carried out by companies based in the United States, Rentmatix and this is probably the only commercial player that uses supercritical hydrolysis technology as a cellulose sugar production line, namely with a production of 100,000 tons / year. This sugar can be produced from a variety of raw materials and can be converted into various biochemical products, biofuels, and polymers either through biological or chemical process routes. One of the applications of cellulose sugar is a bioplastic raw material. Plastic itself is a polymer product. The high level of environmental pollution due to plastic from petrochemicals encourages the use of renewable materials. The company has even made a partnership with the paper industry in Europe for the production of this cellulose sugar. According to the company Rentmatix, 1 million tonnes of cellulose sugar is said to be sufficient to make biodiapers for 24 million babies over 3 years or fly 100 Boeing 747 planes for 8 consecutive days or make 120 billion compostable plastic cups or run 1 million cars 2000 miles on bioethanol or paint for 14 million new homes. Renewable chemicals can also be produced using cellulose sugar as raw material. Currently, there are also many factories that produce bioethanol for liquid fuel by this process route, namely the C5 and C6 sugars which are produced and then fermented to produce ethanol, so it is commonly called the biomass to ethanol process.

 

Cellulose sugar is used as a renewable resource for the biochemical and biofuel industries and can be used to produce intermediates through the fermentation process. The availability of industrial sugar from renewable sources, in sufficient quantities and at favorable costs, allows the product to be cost-competitive compared to products based on fossil fuels. A 2012 study by Nexant predicts that in the future, it will be possible and economically potential to produce all types of sugar-based chemical products from biomass due to developments in cellulose processing.