Textile And Garment Industry: Fight A "Resource Substitution" Protracted War

As long as human beings exist for a day, textile and clothing are indispensable livelihood industries.

Judging from the current structure of textile raw materials, cotton and

In fact, in recent years, the textile and chemical fiber industry has defined a "bright road" supporting the sustainable development of the industry -- biomass fiber and biochemical raw materials industry.

But because the industry itself is at its primary stage, it will take a short time to generate enormous economic and social benefits. Therefore, more extensive force participation is needed.

The two Forum on biomass fiber and biochemical raw materials held in China's Bio Industry Conference has sounded the charge for this industry.

In particular, how to achieve raw material substitution and process substitution within 30 years has been explored deeply and concretely.

The use of cellulose will also remove obstacles.

The ultimate goal of developing biomass fiber and biochemical raw materials is to achieve material substitution and process substitution.

At the same time, the traditional way to realize the differential development of textile chemical fiber products has come to an end. Biochemical technology will bring new breakthroughs in product differentiation.

For this reason, the "biomass" has been widely discussed in the forum recently.

The data is indeed tempting, but what is the feasible way to support these goals? The industry thinks that developing the raw material pattern of straw, bamboo, linen and other fast growing forest materials and rich viscose fiber and other regenerated cellulose fibers is the first consideration.

The 30 year roadmap shows that the regenerated cellulosic fiber industry has replaced 10% of raw materials (except raw materials such as short fiber and wood pulp) in 2020, reaching 20% in 2030 and 40% in 2040.

Cellulose is the most abundant polymer material in nature. It is not only a wide range of sources, but also a renewable resource.

According to scientists, the natural world produces hundreds of billions of tons of cellulose per year through photosynthesis.

However, only about 60 billion tons of cellulose are used by people.

The biggest obstacle in the application and development of cellulose is the high crystallinity of natural cellulose, and a large number of hydrogen bonds exist between molecules and molecules, which make them insoluble in most organic solvents.

Taking straw, straw and other crop straw fibers as an example, their fibers are short and uneven, with less fiber content and more heterozygous cells, with high ash content and large silicon content.

From the commonly used plant materials,

Although some progress has been made, the utilization technology of natural resources has yet to be developed.

To this end, the 30 year roadmap has introduced 10 technologies, namely, straw high efficiency and low energy consumption pretreatment technology, biological and French hemp comprehensive treatment technology, high efficiency and low cost cellulosic bacteria and enzyme production technology, ionic liquid new medium, high value product technology in cellulose production, lignin modification processing technology, lignin melt spinning technology, industrial enzyme and biocatalyst, marine biomass comprehensive utilization, biomass fiber high performance technology, biomass biomass full utilization technology integration and ecological industry chain establishment.

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Multipath trial instead of viscose method

On the one hand, the research of new technology is to make use of the more extensive natural resources. On the other hand, it is also to make the production process more efficient and clean, and reduce the harm to energy use and environment. That is to say, in the roadmap of 30 years, "biochemical process" is used to achieve "process substitution".

The initial planning for the 30 year road map will reach 5% in 2020, 17% in 2030 and 24% in 2040.

Since the invention of viscose process for regenerated cellulose fibers in the late nineteenth Century, more than 100 years have passed. New technologies for producing biomass fibers are emerging. However, viscose still occupies an unshakable leading position from the proportion of fiber production.

Although the viscose fiber industry has made great efforts in cleaner production and achieved obvious results, the black liquor produced during its pulping process can not completely eliminate environmental pollution.

In order to solve this problem thoroughly, the industry has become more and more brave and has been exploring new ways of environmental protection and efficiency for many years.

At present, there are ways to produce regenerated cellulosic fibers in a certain climate and environment. One is the new solvent method, that is, Lyocell (lysell), which represents Shanghai textile (Holdings) group, the Chinese Academy of textile science and Xinxiang chemical fiber, the two is the son liquid method, and the key is Shandong Hailong; the three is the recent low temperature dissolution method of water system, which is highly concerned by the industry, and is developed by the team led by Professor Zhang Lina of Wuhan University.

Cellulose fibers produced by solvent method have been studied in China for several years, but their progress is slow.

Even if the scale of industrialization has been formed, the economic benefit and technology maturity need more consideration.

The preparation of cellulose by solvent method is all about how to weaken the hydrogen bond between cellulose fractions.

Zhao Qingzhang, consultant of the Chinese Academy of textile science, explained in detail the difficulties of the solvent method: first, the technology has high demand for raw materials and no space for later adjustment; two, the dissolution process is short and the scope of dehydration is narrow and continuous; three, the spinning process must be dry spray wet spinning process, the spinning solution has very high viscosity; four, the NMMO itself has certain instability as solvent, and a series of safety measures need to be taken; five, solvent recovery should meet the requirements of high recovery rate and energy saving, and only when its recovery rate is greater than 99% can it have the economic value of industrial production.

At present, Lenzing is still the only company with large Lyocell fiber production capacity. In 2010, its capacity increased by 10 thousand tons to 140 thousand tons.

Using 7% sodium hydroxide (NaOH) /12% urea aqueous solution, the solvent can cool down to 12 degrees below zero, and can rapidly dissolve cellulose (its molecular weight is below 1.2 * 105). The dissolution time takes only 2 minutes to reach the fastest dissolution rate in the history of cellulose. This is the low temperature dissolution method developed by Professor Zhang Li Na of Wuhan University.

It is understood that the cost of this method is slightly lower than that of viscose method, and there is no special requirement for production equipment.

Zhang Lina has won the highest prize in the field of cellulose and renewable materials in the world.

At present, through the cooperation with related enterprises, the route has achieved preliminary industrialization test results.

Under the suggestion of the academician of the Chinese Academy of engineering, Zhang Lina's team is working with Tangshan Sanyou Xingda chemical fiber, and the future prospect is worth looking forward to.

Synthetic fibers change the traditional polyester image

In the biological family, biomass synthetic fiber has a large volume.

It not only inherits the advantages of traditional synthetic fibers, but also has biodegradable and comfortable properties because of its biological structure.

In the 30 year roadmap plan, the target of biomass synthetic fiber material substitution was 5% in 2020, 10% in 2030 and 20% in 2040; the target of process substitution was 5% in 2020, 10% in 2030 and 15% in 2030.

At present, biomass synthetic fiber mainly includes PTT, PLA, PHBV, PBS fiber and so on, that is, the new polyester fiber usually referred to.

In April this year, the appraisal of key technologies and industrialization achievements of PTT series fiber and high value-added fabric manufacturing was held in Jiangsu sunshine Limited by Share Ltd.

After years of development, PTT fibers and industrial applications are maturing.

At the same time, raw material PDO (1, 3- propylene glycol), which has long been restricting the development of PTT fiber industry, has made gratifying progress in production and production.

Such as Jiangsu Sheng Hong group not only owns 30 thousand tons / year specialized PTT spinning production line, but also builds PTT polymerization production line, and produces raw materials 1, 3- propylene glycol, forming a complete PTT industry chain, breaking foreign monopoly.