Status of Hazardous Waste Recycling By R. K. Garg
Introduction Wastes are generated in all Human Activities viz. Domestic & Commercial (Municipal Waste) Health Services (Biomedical Waste) Industries (Toxic & Hazardous Waste) e-waste Agricultural Waste Construction & Demolition Waste However, the quantity and nature of these wastes are vastly different.
Introduction Wastes are generated during the process of manufacture of products as well as after the product utility is over. Manufacture Product Waste Wastes, if not managed properly can have an adverse impact on the environment and the health of people.
Hazardous Waste Hazardous wastes are of greater concern since they contain toxic, flammable, explosive or corrosive constituents. Recognizing the highly adverse impact of hazardous waste on the environment and the health of the people the Ministry of Environment and Forests (MoEF), framed rules entitled Hazardous Wastes (Management and Handling) Rules as early as 1989 under the Environment Protection Act 1986. Subsequently for other wastes also rules have been made. These rules were amended from time to time. In September 2008, new rules entitled Hazardous and other Wastes (Management, Handling and Trans-boundary Movement) Rules came into force in place of the earlier rules. In April 2016, these rules have also been superseded and new rules have been notified.
Definition Hazardous waste means any waste which by reason of its physical, chemical, biological, reactive, toxic, flammable, explosive or corrosive characteristics causes danger or is likely to cause danger to health or environment whether alone or when in contact with other wastes or substances and shall include: Wastes specified in Schedule I Wastes specified in Schedule I Wastes having constituents specified in Schedule II in concentration equal to or more than the limits indicated in that schedule in Class A and B and characteristics as specified in this schedule. Wastes specified in Schedule III (Part A) in respect of Import or Export of wastes, or wastes not specified in Part A but exhibit characteristics specified in Part C of this Schedule.
Schedule-I Lists processes / industries (38 no s) which generally produce hazardous wastes ex. Petrochemicals, Petroleum refining, Reprocessing of used/waste oil, Metallurgical industries including surface treatment operations, Asbestos containing processes, Fertilizers, Processes involving Chemicals and Solvents, Paints, Drugs & Pharmaceuticals, Pesticides, Pulp & Paper, Used Electronics, Leather, Air and Water treatment processes etc. It may be noted that high volume low effect wastes such as Fly ash, phospho-gypsum, red mud (from alumina refineries), slags from pyrometallurgical operations, mine tailings and ore beneficiation rejects are excluded from the category of hazardous wastes. Separate guidelines on the management of these wastes are to be issued by Central Pollution Control Board (CPCB).
Schedule-II This schedule provides the concentration of the hazardous constituent in the waste above which the waste will be considered as hazardous. The concentration in Class A is the leachate concentration(in mg/l) determined by the Toxicity Characteristic Leaching Procedure(TCLP) or soluble threshold limit concentration(stlc) These procedures are included in the manual for characterization and analysis of hazardous waste published by CPCB. For constituents in Class B, the total concentration(in mg/kg) is the limit above which the waste will be considered as hazardous. For other constituents, characteristics given as per Class C shall be applicable.
Schedule-III Schedule III is divided into Parts A & B/D (based on the Basel convention (Annexure VIII & IX) and procedure for Import & Export (only for the purpose of recycling/reprocessing/reuse) has been indicated for each of the wastes. Part C lists the characteristics for identifying the hazardous nature of the waste. No hazardous waste can be imported for disposal.
Hierarchy of Waste Management Reduce waste by change of process/ technology Reuse, Recycle, Reprocess Dispose of in any of the following ways: Physico-chemical treatment Biological treatment Incineration Containment in secured landfill
Recycling of waste has to be explored as the first option since many wastes contain valuable resource or can be used as supplementary source of energy in certain industries as such or after some pre-processing. Also, there is saving of space otherwise required for disposal. Other environmental benefits of recycling include lower energy consumption in recovering of the resource as compared to the natural source like minerals and lower environmental pollution.
Recycling / Reprocessing / Reuse of Hazardous Waste Commonly recyclable wastes and actually being recycled are listed in Schedule IV of the Rules. Earlier, facilities for such recycling were required to be registered with CPCB/SPCB. Now, they need only authorisation from SPCB. Guidelines/Standard operating procedures for such recycling have been prepared by CPCB and need to be followed by the recyclers. For other wastes also, guidelines will be prepared by MoEF and CC or CPCB from time to time. Where guidelines are not available, recycling or utilization of the waste will need the approval of CPCB after carrying out trial run.
Present Status of Hazardous Waste 1) Generation: Management Presently there are more than 40,000 industrial units in the country producing hazardous waste of the order of 7.9 Million Tons/annum (as per authorisation) About 3.98 Million Tons is recyclable 3.32 Million Tons land fillable 0.60 Million Tons is incinerable.
Present Status of Hazardous Waste Management 2) Recycling/Reprocessing: More than 1,000 recycling/reprocessing units have been registered for recycling of wastes like used lead acid battery scrap and other lead and non-ferrous metal(cu, Ni, Zn, Co, V etc.) scrap, process residues, waste oils and used lubricating oils. Registration has also been given for e-waste recycling as well to a number of units in various states
Technologies employed for recycling 1. Metal Wastes Melting in case of scrap where the metal is in the elemental form Chemical leaching where the waste is in oxidised form or in very low concentration 2. Used Oil The process involves dehydration, vacuum distillation and decolourisation 3. Organic Waste Can be used as supplementary fuel in cement industries 4. Electronic Waste Involves dismantling, crushing, physical separation of glass, metals(iron, copper and aluminum) and plastics and recovery of precious metals
Technologies employed for recycling In respect of high volume and low effect industrial wastes, the status is as follows: Fly ash substantial amount is being used in cement plants Slags are also used in cement plants and some for construction Phospho-gypsum Cement Plants and Panel Boards and some in agriculture Red mud presently there appears to be no utilisation
Conclusion From the above it can be seen that the recycling of hazardous and other waste has made some progress However, there is scope for further development on utilisation of other wastes which, by default, are presently going for landfill. One such example is salts generated in the pharmaceutical industry Utilisation/recycling of waste has to be made a national mission like Swacch Bharat, Make in India for conservation of resources and for protection of the environment and health of the people.