The indiscriminate discharge of solid wastes, particularly domestic and hospital sewage has become the prime source of water pollution in Bangladesh. Only half of generated wastes are disposed of in low lying areas or into the canals and rivers and rest of the solid wastes lie over strewn on roadsides, spilling around the bins, clogging the drains and consequently aggravating inundation during the rainy season. In this connection it may be mentioned that during the recent holy Eid ul Azha, in addition to other urban areas, only Dhaka city was burdened with unbearable load of more than 28000 tons of animal wastes in the wake of slaughtering around 4.75 lakh sacrifice animals .
Beginning from Eid noon till the day following the Eid (3-9-2017), almost 100% of the animal wastes of Dhaka city could be removed on account of the commendable service extended by 12000 cleaners who worked even on the EID day. (Source: The Asian Age 5-9-2017). Cleaning vehicles took 4686 trips to remove the animal wastes only of Dhaka city. The city had designated special spots (625 in Dhaka South and 549 in Dhaka North) to dump the wastes. (Source: The Bangladesh Observer 4--9-- 2017). But sadly, many were found totally irresponsible pertaining to the use of designated spots and forgetful of the valuable teaching of Islam 'cleanliness is next to godliness '
Wastes, commonly viewed as menace to public health inviting environmental pollution, is a bye product of growth-both industrial and agricultural including livestock. But these awful and detestable wastes can easily be turned into wealth by setting up waste to wealth enterprises. Among animal wastes use of cow dung or cattle manure is a popular and advantageous practice in the rural area to make the soil fertile enough. The composition of cow dung manure is basically digested grasses and grain.
Composited cow dung manure provides an excellent fuel to the growth of agriculture as well as garden plants. When cow dung is kept for 3-4 weeks for compositing, it then attains fertile efficiency and is fed to the plants and vegetables. According to a study conducted in Bangladesh by POBA (Paribesh Bachao Andolon) some 1.15 crore cattle were estimated to be slaughtered throughout the country during the Eid ul Azha. And from the Eid animal source there is a wide scope to produce some 4.15 lakh tons of organic fertilizer valued at taka 2075 crore (source: The Asian Age 1-9--2017). A recent Indian study reveals that in the urban area 40 % of solid wastes thrown away is paper wastes. The implication is that every 100 kg of wastes thrown away 40 kg of it is paper. In India the set up enterprises has the capacity to recycle 300 kg of wastes to produce 200 kg of paper.
Paper recycling implies the processes carried out to make waste paper for reuse. The prime sources of waste paper are paper mill wastes, pre consumption and post consumption discarded paper materials. The most glaring example of post consumption paper wastes are old magazines and old news papers. Other types of wastes are wrapping and packaging papers. Paper recycling activity can start from collecting wastes discharged by home, office, educational institutions and even from the 'drop of centers' and more importantly from commercial outlets that generate paper wastes. After a series of manufacturing processes for the reuse of paper wastes, the resultant paper sheets are trimmed, rolled and sent to different business floors.
A few examples of reuse of paper wastes are news paper, printing paper and wrapping paper. The study also reveals that paper recycling can be made approximately 7 times. Each time the paper is recycled its length decreases which impacts its strength. This economically sound and environment friendly technique helps to a large extent in cleansing the environment with minimum landfills. To conclude, in Bangladesh physical composition analysis of wastes shows that there is a mixture of different types of components with 74% of them being compostable. This absolutely high amount of organic content is indicative of bright prospect for organic wastes recycling through compositing.
Our existing infrastructure of waste management demonstrates that overall waste collection efficiency in different urban areas is estimated on average only 55% which is far from satisfactory. Huge amount of stinking heap of animal and other wastes polluting the local environment are not removed on regular basis. Ultimate disposal of urban solid wastes is done crudely in an open dumps, low lands or water bodies in an unhygienic manner. The increasing demand for land fill is also a big problem for the authority to find suitable spot for dumping wastes.
At current urban wastes generation rate (it is estimated to be per capita daily 0.41 kg according to a study in 2004) total land required per year to absorb the wastes will be 273 acres with a depth of 4 meters (assuming that 100% wastes collection efficiency is attained). Therefore, compositing can significantly reduce the landfill load in addition to earning revenue from the sale of compost. . In some parts of the world like European countries dumping of organic wastes in landfill was to be banned by 2010. To improve our situation there is an urgent need on the part of the Govt. to implement an effective solid wastes management policy.
The writer is a former General Manager,Credit Information Bureau, Bangladesh Bank