Waste Control in Downstream Industry
B P Singhal
Head of Projects & Purchase
India Glycols Ltd

Industrial growth & rapid urbanization resulted in increase in waste generation. India faces major environmental challenges associated with waste generation and inadequate waste collection, transport, treatment and disposal. Current systems in India cannot cope with the volumes of waste generated by an increasing urban population, industrial growth, and these impacts on the environment and public health. The challenges and barriers are significant, but so are the opportunities.

What is waste - Any residues which causes potential hazard to human or environment either alone or when in contact with other wastes and which therefore cannot be handled, store, transported, treated or disposed -off without specific precautions. Waste can be Industrial, Municipal and can be further broadly classified as hazardous & nonhazardous.

Sources
  • Inorganic & organic chemicals
  • Petroleum refineries
  • Iron & steel
  • Non Ferrous Metals
  • Leather tanning
  • Metal finishing
  • Distilleries
  • Coal mining
Objective

1. Waste minimization by source reduction, recycling & waste exchange.
2. Detoxification & neutralization of wastem by treatment
3. Destruction of combustible waste by incineration
4. Solidification of sludge and ash from step 2&3 above
5. Disposal of residues in landfills

Treatment Methods
  • Physical treatment - Separation, screening, sedimentation, centrifugation, RO
  • Chemical treatment -Neutralization, precipitation, oxidation & reduction
  • Biological treatment -Use of microorganisms for degradation
Hazardous Industrial Waste

Hazardous wastes, which may be in solid, liquid or gaseous form, may cause danger to health or environment, either alone or when in contact with other wastes. Various agencies have defined hazardous wastes in different ways and as such, there is no uniformly accepted international definition so far. It is presumed that about 10 to 15 per cent of wastes produced by industries are hazardous and the generation of hazardous wastes is increasing at the rate of 2 to 5 percent per year

Hazardous industrial wastes in India can be categorized as :
  • Hazardous wastes generated from various industries.
  • Hazardous industrial wastes imported into India from Western Countries for reprocessing and recycling.

Use of Hazardous Wastes as Alternate Fuels

In India, about 4.43 million tons of hazardous wastes are generated annually , out of which 71,833 tons are incinerable (as per the reports of SPCBs submitted to the Supreme Court of India). There is a need to explore the possibility of using such wastes by other industries.

Incineration

Incineration serves the dual purpose of reduction of both the toxicity and the volume of the waste, which is an important consideration when the disposal of wastes is finally destined for landfills. Most of the process wastes from chemical unit operations can very well be treated in properly designed incinerators.

Hazardous wastes (secured) landfill

Hazardous waste landfill site is designed scientifically to have an impervious stratum at bottom to stop leachates percolation, and thus to avoid soil and water pollution/contamination in the vicinity of the landfill site. HDPE lining is used in making the landfill impervious. There are arrangements made for collection and treatment of leachates from the hazardous wastes.

Non-Hazardous Industrial Waste

Non-hazardous or ordinary industrial waste is generated by industrial or commercial activities, but is similar to household waste by its nature and composition. It is not toxic, presents no hazard and thus requires no special treatment.

Treatment options for Non-hazardous Industrial Waste

Nonhazardous industrial wastes being diversified in their chemical nature, physical texture and moisture content and calorific values etc. demand distinct treatment options which are broadly classified in the table below.

Limiting factors
  • High cost of installation
  • Wrong selection of technology
  • High Opex cost resulting in closure or intermittent running of these plants.
  • Many a time, Technology provider suggest some technology to end user without going in the chemistry of waste/discharge (Solid, liquid , gas) and provide low capex system which finally result in nonperforming asset to a company.
  • High operating & maintenance cost
  • ROI nil, so management approval for such installation capex take time and only approved under compulsion of statutory requirement.
  • It can be part of CSR - this is way of giving to society and to nature.
The key to efficient waste management is to "ensure proper feed input to the process resulting in simpler treatable effluent "and segregation of waste at source and to ensure that the waste goes through different streams of recycling and resource recovery

Conclusion

Government/nominated Govt. authorities to educate, guide on technology selection & shall provide solution for treatment of industrial waste as different industry has different characteristic waste. Tax benefits and financial aid to be extended to Technology & Plant Supplier including end user for installing waste management systems/pollution control equipment’s which need heavy investments. Medium & small scale industries are finding it's difficult to invest on getting technology & installing these waste recovery or waste treatment plants. Taxes /GST/ import duties to be made Zero and financial aid for such plants to reduce cost burden. There are many ongoing policies to support waste management but are not effective or promoters not aware, Government to support by means of providing financial support for such technologies which results in developing indigenous technology under MAKE IN INDIA - dream project of our Prime Minister and also create employment. Our generations to come, can see a better & greener earth.