jute and environment



Jute & The Environment



The worldwide awareness on environment and health is likely to provide new opportunities on jute, due to its environment-friendly characteristics. Jute and kenaf have been employed for centuries as packaging materials. In recent times they are found to be a valuable aid to sound environmental management.

Jute, a natural fibre that can be used in many different areas, supplementing and/or replacing synthetics, has been receiving increasing attention from the industry. Their interests focus not only on the traditional uses of jute, but also on the production of other value-added products such as, pulp and paper, geotextiles, composites and home textiles etc.

Jute is an annually renewable energy source with a high biomass production per unit land area. It is biodegradable and its products can be easily disposed without causing environmental hazards. The roots of jute plants play a vital role in increasing the fertility of the soil. By rotating with other crops like rice and potatoes, jute acts as a barrier to pest and diseases for others crops and provides also a substantial amount of nutrients to other crops in the form of organic matter and micronutrients. Jute and kenaf have ecological adaptability, and can be grown on a range of soil types. They have a good tolerance to salinity, water stress and water logging. Agronomically, jute and kenaf have advantages as regards their resistance to climatic extremes, pests and diseases.

Jute plants have high carbon dioxide (CO2) assimilation rate and it clean the air by consuming large quantities of CO2, which is the main cause of the greenhouse effect. Theoretically, one hectare of jute plants can consume about 15 tons of CO2 from atmosphere and release about 11 tons of oxygen in the 100 days of the jute-growing season. Studies also show that the CO2 assimilation rate of jute is several times higher than that of trees. (Inagaki, 2000).

Jute is a fast-growing seasonal crop. It reaches a height of 1.5 to 4.5 meters in a period of 4 to 5 months. The average dry stem production of jute ranges from 20-40 ton per hectare, annually. This contrasts with the production of the fastest growing wood plant which needs at least 10 to 14 years from plantation to harvest, and produces only 8 to 12 ton per hectare annually. Because the biological efficiency of jute is much higher than that of wood plants, the use of jute instead of wood to make paper pulp will lower substantially the cost of production of pulp and paper and save forest resources. (Liu, 2000)

The defoliated jute leaves have fertilizer value and enriches the soil nutrients. Jute leaves are used as vegetables and have nutritional as well medicinal values jute sticks are used for fuel and shelter in jute growing rural areas. This has helped reduce the use of wood in these applications. For Instance, the total production of jute & kenaf fibre in the world is 3 million tons. This means that on an average 6 million tons of jute sticks are available to the rural people for use as firewood etc.

The production flow of jute agriculture involves: sowing, weeding/thinning, harvesting, defoliation, retting, fibre extraction, washing and drying. But only a small percentage of the farmers use seed treatment, fertilizers and herbicides/pesticides, which makes the processes before harvesting environmentally sound. Processes of jute retting, fibre extraction and washing have drawn some concerns regarding solid residue and gaseous emissions that arise from such processes. Complaints about the unpleasant smell during retting are quite common. However, the pollution of water by retting is transitory in nature, because in a warm climate the polluted water returns to its normal condition after 30-45 days. The temporary gaseous emissions and unpleasant smell do not involve any non-reversible hazard as compared to some other industries. The retting process is being improved using biotechnology. 

Jute products manufacturing process involve several stages such as batching, softening with batching oil, carding, drawing, spinning, weaving and finishing. The use of mineral batching oils is being replaced with for specific use like packaging of Cocoas and Coffee.

Jute contains cellulose like any other raw materials used for paper pulp. Experiments to convert jute fibre and whole jute plant into paper pulp have successfully produced good quality pulp and paper. The growing demand of pulp and paper worldwide on a continuous basis and increase of public awareness on environmental issues have created conditions to check depletion of forest resources through using jute/kenaf for producing pulp and paper. This increasing demand for paper has led to excessive deforestation in both developed and developing countries. The restoration of the forest resources is difficult because of the relatively long growing cycle of trees. This situation will increase the competitiveness of jute as a raw material for paper pulp and the paper industry.

Jute can be used for the production of good quality writing and other papers. Furthermore, using jute for pulp and paper has many advantages, like (i) using less chemicals than in wood pulping, like chlorine; (ii) consuming less energy than traditional wood pulp due to the low lignin content of jute; (iii) using treated wastewater from jute paper mills for irrigation, etc.

Jute fibre has the potential to compete with glass fibre, as reinforcing agents in plastics. Technologies exist that make it possible to incorporate jute fibre into polypropylene. The resulting jute composite granules can be used in thermoforming processing techniques, such as injection moulding and compression moulding. Products made from jute-reinforced composites have the advantage of low cost, low density, renewability and biodegradability. This composite can be used, in the packaging industry, i.e. the manufacturing of crates, boxes or cases used for storage and transportation of agricultural products; in the automobile industry, i.e. to replace glass fibre in car door panels; and as construction material.

Applications of jute-reinforced composites are expected to have a significant positive environmental impact. This contrasts with the situation existing at present, because the packaging industry is responsible for about one-third of the plastic consumption in developed countries, and accounts for the production of 20.8% of total solid waste and 3.7% of energy consumption.

Particleboard made from Bast fibre, core fibre or the mixture of both can find a wide application as substitute of wood. The availability of the technologies for producing particleboard and its high socio-economic value are solid arguments in favour of the future development of this product.

Jute geo-textile is another product with a potentially large-scale application. It can have several uses: soil erosion control, vegetation consolidation, agro-mulching materials, and road pavement construction.

Jute, for its versatility, rightfully deserves to be branded as the “fibre for the future”. It is the natural option for a cleaner and healthier the environment.