Updated: Jan 29, 2021
Bamboo is a natural fiber obtained from Bamboo plants. This fiber comes under the class of grass fiber (natural-grass-bamboo). India is the second-largest producer of bamboo after china. Bamboo fiber is stated as the green, natural, and eco-friendly type of textile-fiber of 21st century as this fiber degrades naturally in soil by sunlight and micro-organisms, this decomposition/ degradation process will not cause any pollution.
According to FSI, about 8.96 million hectors of Indian forest land is covered with bamboo plants, i.e., 12.8% of total forest land. The annual bamboo production of India is approximately 3.23 million tons.
Extraction of Bamboo fiber:
There are two major ways of extracting bamboo fibers from bamboo plants.
Mechanical Method: There is various forms extraction of bamboo fibers mechanically, like Steam explosion, Crushing, Grinding, Rolling mill and Retting.
Steam explosion: This process consumes little amount of energy to produce pulp. Fiber is dried for 2 hours at 120oc, so that lignin content from the fiber removed completely. Then bamboo is placed in an autoclave for 60min at 175oc and at 0.7-0.8 MPa, then raise the steam for 5min and for 9 more times, repeat this process until cell walls of bamboo were fractured. As the cell walls get cracked the fiber becomes smooth and contains low shear resistance. To remove the ash from the cells it should be washed in the hot water at 90-95oc and then dry it for 24 hrs. at 105oc. Crushing: In this process, the first bamboo is cut into small pieces with the help of roller crusher. To extract the fibers from this cut pieces, it is placed in pin-roller. Then fibers are boiled for 10 hrs. at 90oc, this is done to reduce fat. Then dry the fibers in the rotary dryer, and then in a dehydrator. In this process, only staple fibers are produced.
Grinding: In this process, the first bamboo is cut into small pieces without node, then soak in water for 24 hrs. later these soaked strips are cut into small pieces with the help of a knife. Wider pieces are sent to extruder and longer pieces are cut into small bamboo pieces. These cut pieces are ground in a high-speed blender for 30 min to obtain short bamboo fibers. Later fibers are separated based on length by use of various instruments. Finally, these extracted fibers are dried in an oven for 72 hrs. at 105oc. Rolling mill:
In this process bamboo is cut into pieces of 1mm thickness, then these pieces are soaked in water for 1hr, then they are passed through rolling mill under low pressure and speed. After rolling these fibers are soaked in water for 30 min, and then fibers are separated by using a razor blade. These obtained fibers are dried in sunlight for almost 2 weeks. Then length rage of fibers produced through this process is 220-270mm. Retting: In this process, bamboo is peeled longitudinally along with node. These stripes are soaked in water for 3 days. Wet stripes are beaten, then scraped with a sharp edge knife and combed. Chemical method: In chemical extraction method there are two ways 1. Chemical retting. 2. Alkali or Acid retting.
Chemical retting: In this method, bamboo is cut into thin pieces in a longitudinal direction with a slicer, these pieces are manually placed in Zn(NO3)2 solution of 1%, 2%, and 3% concentrations, this solution is of 1:20 M:L, at 40oc for 116 hrs. at pH-7 in a BOD incubator. Then for 1 hr., they are boiled in hot water.
Alkali or Acid retting: in this process bamboo pieces are heated with 1N NaOH solution in a stainless steel container at 70oc for 5 hrs. then these pieces are pressed using a press machine and by use of steel nail, fibers will separate. Wash the fibers with water then dry in an oven.
Bamboo processing through enzymes:
Application of bamboo fibers:
Used in bed linen
Bathrobes, bath mats, towels
Apron, Oven gloves, apparels etc.
Merits of bamboo fiber:
Soft and silky to touch
High absorbency material
Odor absorption properties.