| Popis: |
Flax can be used in many industrial sectors like textile, linseed oil, flax seed oil, pulp and paper production and composite materials. However, the conventional growing of flax pollutes water via a process called retting. Retting is defined as microbial process to separate the fiber from the non-fiber stem tissues (woody part), and removal of non- cellulosic components, such are pectin, hemicelluloses, lignin, waxes and fats. Retting method plays an important role in producing a good quality of fibers, with high homogeneity and fineness. The process of retting flax produces a huge amount of wastewater, which is characterized with bad unpleasant smell, and high concentration of various types of organic and inorganic compounds what it causes water pollution. There are various types of retting, for an example dew- or water-retting, using chemical or enzymes, retting with ultrasound. The results of the influence of different retting methods on wastewater quality are presented. For this purpose, enzymatic retting, physical retting with ultrasound and chemical retting with sodium hydroxide were performed. The efficiency of the applied retting methods were determined by measuring the fiber fineness and tenacity and comparing with the same fiber properties after traditional retting. Also, the quality of wastewater after different retting methods were determined by measuring pH, conductivity, COD, BOD, suspended solids, color and turbidity. The use of ultrasound to extract fibers resulted in the best fiber properties and provides an environmentally friendly method with the best wastewater quality, which is nowadays enhanced to perform. Additionally, taking in account the economy of the process, fast enzymatic retting can be considered as well. |
