Why pulp wastewater treatment is important

Hello, I'm Sohee Jeon, a manager at ARK. Continuing our series on lithium-ion batteries, today we'll be looking at the paper industry, which is in the midst of a global R&D battle to replace plastic with nanocellulose.

We'll start with information on wastewater treatment and end with the recycling of lignin and black liquor. We will continue the series with the following parts.

vol.1 > From paper and pulp wastewater treatment to nanocellulose and bio-aerosols
vol.2 > Domestic paper and pulp companies Hansol Paper and Murim P&P and overseas resource recycling cases (tentative)
vol.3 > Overseas research activities related to paper/pulp black liquor (tentative)
vol4. > Introduction of environmental facility construction companies and contractors related to paper wastewater in Korea (tentative)

---

‘종이1톤을 생산하는데 물100톤이 필요하다’ 라는 말을 들어보셨나요? A4로만 생각하시던 제지 및 펄프 제품은 우리 생활속에서 플라스틱만큼이나 아주 쉽게 만날 수 있습니다. 플라스틱은 일반적으로 ‘생분해성’의 기술까지 나왔지만 미세플라스틱의 환경영향학적, 생체에 미치는 영향은 아직 상대적으로 덜 알려졌고 나무가 주는 이미지에 비해 환경에 좋지 않다는 인식이 지배적입니다.

우리가 아는 제지-펄프 산업은 많은 양의 물과 열에너지를 사용하며, 폐열-폐액을 자원순환함에 있어 그 효율은 상당수준으로 올라와 있고 더 나아가 나무의 단단함을 유지시켜주는 리그닌과 제지펄프에 실제적으로 쓰일 셀룰로우스를 분리하는 과정에서 발생하는 흑액 또한 소각연료로 쓰며 분리된 리그닌 또한 전세계적으로 이를 자원재순환해 새로운 바이오연료를 생산하는 연구개발과 ‘나노셀룰로우스’를 얻으려는 기술을 연구중입니다. 때문에 나무는 아낌없이 버릴게 하나도 없는 친환경 그자체입니다.

Wastewater treatment in paper pulp is very important, but when it comes to resource recycling beyond wastewater treatment, nanocellulose technology is getting more attention than lignin and cellulose.

The global technology leaders in nanocellulose are Canada, Japan, Finland, and Norway, which are leading the way in manufacturing technology and research and development (R&D). Major companies include Kruger Inc. in Canada, Nippon Paper Group in Japan, Beauregard in Norway, and Fiberlean Technologies in the UK. Canada is a global leader in nanocellulose technology, and its use in a variety of applications is growing.

Korea is another country where Murimphy & P excels in technology.

Therefore, this series will start with paper and pulp wastewater treatment, but we will also share the environmental talk with you by providing insights into the resource recycling efforts of Korea's proud paper and pulp manufacturers and nanocellulose.

First, the domestic major paper and pulp companies are the white cardboard industry's Hansol Paper, Clean Country, Hanzhong PaperThe printing paper is manufactured by Hansol Paper, Forest Paper, MurimP&P and more.

It is also a highly technologically advanced and competitive industry with excellent performance of domestic companies that have become world-class luxury papers. It has become an important everyday consumer product with the growth of e-commerce, while being eco-friendly and contributing significantly to ESG management.

Since the COVID-19 pandemic, the rapid growth of contactless distribution has brought many changes to our society. In particular, the expansion of online shopping markets and delivery systems has dramatically changed the way consumers buy. In this environment, the demand for white paperboard has increased significantly. While the production of traditional printed paper has decreased globally due to the one-to-one digital machine replacement, the market for e-commerce paperboard used for parcel boxes and thermal paper has increased.

White paperboard is used as a high-end packaging material in various fields such as confectionery, pharmaceuticals, cosmetics, and more, enhancing the quality of products. In 2020, sales reached approximately KRW 189.5 billion, an increase of 6.71 TP3T year-on-year, followed by KRW 204.4 billion, an increase of 7.91 TP3T in 2021, and KRW 227.3 billion, an increase of 11.21 TP3T in 2022. This growth is attributed to consumers' desire for high-quality packaging.

Currently, whiteboard is gaining more emphasis as an alternative to plastic due to growing environmental concerns. The market outlook for the future is very positive and it is expected to become a sustainable packaging solution.

That's why it's important for everyday paper, paper and pulp consumers to pay attention to wastewater treatment.

Celluloseplays a critical role in the paper and pulp manufacturing process, and its utilization is expanding throughout the industry. An understanding of cellulose is essential for a deeper understanding of the paper and pulp industry. Below, we'll discuss the role and uses of cellulose in more detail.

The role of cellulose

1. Function as a principal component
   • Cellulose is a polymeric substance derived primarily from wood pulp and is a fundamental component of paper and pulp. As the main component of wood, cellulose directly affects the physical properties of paper and contributes to the production of high-quality paper. For example, the higher the content of cellulose, the stronger and better quality pulp is produced.
2. Structural contributions
   • Cellulose is a fiber-forming substance that forms the cellular structure that makes up pulp. This structure has a significant impact on the strength, durability, and texture of the final product, paper, which is why it's so important to handle cellulose properly in the papermaking process.
3. Chemical modifiability
   • Cellulose can be subjected to a variety of chemical reactions to create esters and ester derivatives with unique properties. These chemical modifications broaden the range of applications for cellulose, allowing it to be used in food packaging, as an excipient in pharmaceuticals, and more.

Where to use

1. Paper products
   • Cellulose is used as the main ingredient in paper, cardboard, and card stock. These products are essential to our daily lives and are an important resource for the paper industry.
2. Textile Industry
   • Cellulose can also be converted into fibers like rayon, which is used in combination with natural fibers like cotton and linen. Rayon is an important fiber that has been around since the early 20th century and is used as an important textile product based on cellulose.
3. Unique new materials
   • 최근 몇 년 간 나노셀룰로오스와 같은 파생물질이 개발되며 자동차 내장재, 건축 자재, 화장품 등 다양한 산업에서 응용되고 있습니다. 나노셀룰로오스는 생분해 가능하며, 가벼우면서도 강도가 뛰어난 특징 때문에 ‘제2의 탄소섬유’로 불리기도 합니다.
4. New applications
   • Cellulose is gaining traction as an alternative to synthetic fibers and is seen as an important resource as consumer demand for more environmentally friendly products grows. It is also increasingly used in the medical, electronics, and packaging industries.

Wood > What lignin is discarded in the production of paper pulp?

Lignin, a discarded treasure, gets a colorful makeover ✨.

여러분, 나무의 단단함을 유지하는 비밀, 알고 계신가요? 바로 ‘리그닌’이라는 친구랍니다. 셀룰로오스와 함께 나무의 주성분을 이루는 리그닌은 나무에 단단한 뼈대를 제공하는 중요한 역할을 하죠.

Unfortunately, in order to make the paper we use, we need to remove the lignin, which is just the cellulose, to make the soft pulp that makes paper. So for a long time, lignin was simply treated as a waste material, because its complex structure made it difficult to utilize. And every year, huge amounts of lignin were being thrown away around the world.

But with the recent interest in lignin, we're seeing a remarkable transformation! What used to be a discarded material is now a treasure trove of new value. There's a lot of research being done on lignin to create a variety of products, and more and more of them are actually being commercialized.

So what can you make with lignin? Nylon raw materials and fuel industries such as vanillin and carbon monoxide.

#Lignin #Eco-friendly #Biomass #Sustainable Development #New Materials

Chemical Pulp

• Chemical pulp: Chemicals are used to separate wood chips into lignin and cellulose, and mainly allyl-based materials use sodium hydroxide and sodium sulfide to extract cellulose. Therefore, lignin separation generates lignin-containing wastewater and sulfide-containing wastewater as described above.

Types and features of mechanical pulses

1. Grinding Wood Pulp (Grinding Wood Pulp)
   • FeaturesThis method uses whole trees and crushes them under intense pressure. It is usually done at a temperature of 70 to 75 degrees Celsius, and yields a very high yield of about 98.51 TP3T. However, the paper quality can be poor due to the high lignin content.
   • Use: Mainly used for newsprint, low-grade magazines, toilet paper, and wallpaper. It is effective in increasing opacity and thickness, but has low durability.
2. Refiner Pulp
   • Features: A process of fiberizing using a machine called a refiner, where high shear forces are applied to crush the chips. The chips are physically processed, usually through a narrow gap between two rotating disks.
   • Efficiency: Often run in multiple stages to achieve the intended fiber length.
3. Pressure Grinding Wood Pulp (Pressure Grinding Wood Pulp)
   • FeaturesA method of punching using wood that has been cleaned after pressure is applied.
4. Thermal Grinding Wood Pulp (Thermal Grinding Wood Pulp)
   • FeaturesIt is a method of processing by heating with water and steam at around 80 degrees Celsius, which changes the physical properties of the pulp and allows for more effective fiberization.

Waste paper recycled pulp

Since it is made by recycling discarded waste paper and soaking it in water, it contains various foreign substances, printed ink, glue, metal stemplers, and harmful substances, and wastewater containing these substances is generated, and surfactants, hydrogen peroxide, formamidine, sodium silicate, etc. are used to separate them.

The types and main components of wastewater from paper and pulp mills are suspended solids, BOD organic matter, and black liquor.
It is important that the black liquid is incineration fuel and the white liquid is white liquid.

Categorize by nature

1. Black Liquor:
   • Definition: Black liquor, a mixture of chemicals, lignin, and other organic matter used in the pulping process, is the wastewater collected within the process. It typically has a high BOD (biochemical oxygen demand) and COD (chemical oxygen demand).
   • FeaturesBlack liquor can be hazardous to the environment and causes pollution problems if discharged without proper treatment. This black liquor is often recycled as a way to recover thermal energy.
2. Singer (Gray Water):
   • Definition: Water used in the pulp manufacturing process typically has low-grade water quality, containing organic matter, residual chemicals, etc.
   • FeaturesThis water has less impact on the environment, but still needs to be treated. If the water from pulp production is discharged outside of the process, it can cause water quality degradation.
3. Sludge:
   • Definition: Sludge, which remains as a sediment during pulp water treatment, is generated in the mechanical pulping process. It contains insoluble solids and contaminants.
   • FeaturesSludge must be disposed of as waste and can often cause environmental problems when dumped into the ocean or land. Efforts are being made to treat it and recycle it as a resource.

Other constituents in paper and pulp wastewater

Additional ingredients based on paper type: Calcium carbonate, starch, ink residue, dyes, etc.
For waste paper pulp : Printed ink, office stampers, etc.