In China, geosynthetics are widely used in civil engineering applications. This began on a trial basis in the 1980s and expanded in the 1990s, when more than 100 million square meters of material was used to remediate large-scale flooding in 1991. In 2002, the size of the geosynthetic market was estimated at 250 million square meters, of which 150 million square meters were nonwovens.
According to CNITA, the Asian nonwovens association, in 2003, 70,000 tons of geononwovens were used in civil engineering applications and 46,000 tons of nonwovens were used in the construction market.
In China, geononwovens include staple fiber needlepunch nonwovens and spunbond needlepunch nonwovens, which are used in water conservancy, highway, railway, construction, port of sea and air and military affairs. The growth rate of geononwovens is about 15%, exceeding the growth of China’s GDP. This has led more nonwovens makers to enter this industry, creating strong competition. Currently, only about 70% of the available capacity is being used.
In the past 20 years, the Chinese government has invested in its infrastructure on a large scale. Large highways, railways and water throughways have been built throughout the country in response to increased economic activity. Investments, both private and public, have stimulated the need for geononwovens in the market. Additionally, a series of design and application standards involve geononwovens. These standards help agencies more easily accept, produce and design construction products.
The Chinese can produce the machinery needed to make geononwovens as well as roll goods. In fact, most of the machines making nonwovens for this market were produced by Chinese manufactures. This is particularly the case with staple fiber needlepunch lines, which have not been imported into China for a long time. The first polyester spunbond line made by a Chinese company is set to come onstream this year.
PET Staple Fiber Needlepunch Geononwovens
In China, both staple fiber needlepunch and spunbond needlepunch are used widely in geononwovens. However, the use of staple fiber needlepunched nonwovens dominates the market with an estimated 80-90% share.
In fact, PET staple fibers, as long as they fit the right specifications, are strong enough for construction applications because they do not tear or puncture. The fiber channels in polyester staple fiber needlepunched nonwovens have a three-dimensional structure because the thickness is big and bulky. Also, its filter efficiency and drainage is good.
There are many manufacturers, both large and small, of staple fiber needlepunched nonwovens doing business in China. Many of them are concentrated in Changsu City, Jiangsu. Many of these companies produce machinery as well as nonwovens.
In China, staple fiber needlepunch nonwovens have been used in Three Gorge Cofferdam in Yangtse, in a retaining wall at an airport and in dumps, highways and railways. Jiangsu Yixin Nonwovens Factory is one of the most important suppliers of staple fiber needlepunch geononwovens in China. Besides needlepunch nonwovens, they also make geocomposite nonwovens with PE films.
The use of geononwovens is increasing rapidly in China.
Xueri Nonwoven Co. operates three German lines on which it makes needlepunch geononwovens and geocomposite nonwovens from PE, PVC and EVA. Product weights range from 100-1000 grams per square meter with a maximum width of 5.4 meters. The company sold 32.4 million square meters of the material between 1993 and 2000 and has already sold more than that since 2001.
The company has also sold 4.6 million square meters into highway applications, helping grow geononwovens’ share of this market from 5 to 43%.
Jiangsu Yunda New Material Co. is also an important geotextile supplier in China. The company produces not only geononwovens but also wovens, knit/nonwoven composites and film/fabric composites for construction markets.
PET Spunbond Geononwovens
In geononwovens, polyester-based spunbond nonwovens have an excellent mechanical performance. The tensile strength of these materials is nearly twice as good as staple fiber needlepunch nonwovens. And, its stretch performance and tear and puncture resistance are better than staple fiber needlepunch geononwovens, and the hydraulics performance is nearly equal to staple fiber nonwovens. However, the higher cost of machinery investment for this technology makes its price significantly higher than staple fiber nonwovens.
In China, the weight of polyester-based spunbond nonwovens is more than 100 gpsm and needlepunched nonwovens are also used in civil engineering and roof construction applications. Lightweight polyester-based spunbonds are used only for daily consumables.
In 2005, there were 240 spunbond lines in China. Twelve, or 7%, are polyester-based with a total capacity of 38,900 tons. The geotextile market consumes about 20,000 tons of the material per year.
Some new markets including termite resistance and road surface splitters are cropping up for special polyester-based spunbond nonwovens. Additionally, the market is using spunbond/film composites in a number of applications.
Jiangsu Yizheng Nonwoven Factory has sold 20 million square meters of polyester-based spunbond geononwovens. Half of this goes to the highway and railway markets. Another 30% is applied to water conservancy and 20% is used in garbage dumps.
Hunan Yiyang Nonwoven is is a specialized manufacturer of polyester spunbond with a capacity of 3500 tons per year. It also operates a polyester staple needlepunch nonwovens production line and a composite geomembrane production line. Reinforcements for roofing membranes and geononwovens are produced. Spunbond nonwovens have a 50% marketshare of the roofing membrane market in China. Products are also exported to Russia, Korea, Japan, the Philippines, Pakistan and more than 20 other countries and regions.
Lida is an important supplier of polyester spunbond for geononwovens in China. In 1995, the company began operating its first polyester spunbond line, which is 2.2 meters wide and soon after added a second, 4.4-meter line. The company has sold about 14.5 million square meters.
Spunbond for railway roadbed Singeing Spunbond for Anti-Split in highway road surface.
Both staple fiber geononwovens and spunbond nonwovens are laminated with film by nearly all of China’s major geononwovens producers. These composites are completed in a two step process and are not laminated online.
Hunan Xueri Co also produces staple fiber needlepunch geocomposite nonwovens, nonwovens/film and film/nonwovens/film. The maximum width is 4.5 meters.