Managing India’s waste key to energy, climate benefits

The emission of greenhouse gases from waste in India is estimated at 0.7 million tonnes of CO2 equivalent − roughly distributed equally between emission of methane from landfills and from wastewater. Maximising resource recovery from waste, both material and energy, along with proper disposal will not only ensure proper management but also reduce GHG emissions.

However, India has a long way to go when it comes to efficient waste management. Among urban waste streams, municipal solid waste (MSW), domestic sewage and e-waste require urgent attention as their current management is far from satisfactory. As per estimates by the Central Pollution Control Board, around 62 million tonnes of MSW is generated per year in India. Out of this, only about 68% waste is collected, and of that only about 28% gets treated.

The total wastewater generated from class-I cities and class-II towns in India is reported at 38,254 million litres per day (MLD) while the capacity of wastewater treatment is only 11,787 MLD. There is a large gap of 26,466 MLD between wastewater treatment and discharge in urban areas. Discharge of untreated sewage is one of the main causes of pollution of water bodies in the country and the focus of various river clean-up action programmes.

India also generates about 1.85 million tonnes of e-waste a year. Some 90% of the collected e-waste is processed by the informal sector and in the process not only harms the persons handling e-waste, but also pollutes air, soil and water at the e-waste processing sites.

The first and foremost challenge is to prepare a proper waste inventory to facilitate long-term planning. A uniform data collection format must be developed for cities and towns to start data collection in prescribed format, to be sent to CPCB for collation and analysis. A suitable data collection format should include information like daily waste generation, collection, waste processed and sent for recycling, and waste diverted from landfills. This information should flow from sanitary inspectors to higher officials through suitably designed Management Information Systems (MIS).

Another key challenge in MSW management is the inability of urban local bodies to get the waste segregated at source and processing the waste, as far as possible, close to the source of generation. Segregation of waste must be made mandatory at the household level and graded collection charges should be levied based on volume of waste generated. Higher charges should be levied from bulk waste generators and excess amount collected should be used to subsidise waste collection in slum areas.

Most large cities currently face challenges in managing their waste disposal sites. Over the years, these sites have become garbage mountains due to disposal of mixed waste. These sites keep generating landfill gas (LFG). The key constituent of LFG is methane, which is a GHG. In adverse conditions, the LFG causes fires in the dumpsites causing local air pollution and release of black carbon, which is a short-term climate pollutant. These sites need to be rehabilitated and redeveloped as scientific landfill sites.

One way to do that is landfill mining, which requires opening of the dumpsite and segregating different constituents of waste by grinding and sieving. The remaining biomaterial can be processed into compost. Recyclables can be sent for recycling and combustible but non-recyclable and non-biodegradable waste (such as rags, soiled leather, footwear, etc.) processed into refuse-derived fuel and sent to industries or cement kilns as alternate fuel and inerts can be used for construction applications.

To facilitate such dumpsite remediation and redevelopment, a national fund such as the superfund of the US Environmental Protection Agency for cleaning up of contaminated sites should be established.

Ensuring the sewage treatment infrastructure works efficiently to its capacity is a challenge in India. Generally, the staff for managing the STPs is not trained adequately to run the plant and troubleshoot day-to-day problems. This can be addressed by creating a special purpose vehicle (SPV) as done for Common Effluent Treatment Plants for industrial wastewater. Also, currently most STPs operate on aerobic treatment processes, hardly recovering water, nutrient or energy. The emphasis in sewage treatment will have to be on recovery of these resources so that if not the capital cost, at least O&M of these STPs can be fully or partially compensated. This will also address the problem of faecal sludge management at the STPs.

Typically, an e-waste processing unit in India recovers plastics, copper, aluminium and iron, which are sent for further refining and smelting. The e-waste recycling units in India are still not equipped to recover precious,
semi-precious metals (gold, silver, etc,) and rare earth metals, thereby losing high-value resources and affecting recycling viability.

As far as the economics of waste recycling is concerned, transportation costs greatly influence economic viability of product recovery. It is, therefore, crucial to look at the present capacity created for e-waste processing, with respect to their locations vis-à-vis hot spots for e-waste generation. It would also be useful to locate these units in a 250-km radius from the bulk e-waste collection points and upgrade them with technologies to recover semi-precious, precious and rare earth metals to ensure resource security.

Overhauling the approach to MSW management will mean that citizens will have to shell out user charges for segregated collection and processing of waste. As the charges will be graded, they will also promote waste reduction and conservation practices in the long run. The decentralised management of organic waste will ensure better quality compost and its uptake by farmers and address loss in soil carbon and its fertility.

Also, managing e-waste stream will impact registered but small-scale e-waste recyclers who do not provide economy of scale in recycling and hence would be inefficient. In the long run, it would help the country in recovering precious and semi-precious materials from e-waste, thus closing the loop as per the principles of the ‘circular economy’.

(The writer is Director, Environment & Waste Management, TERI, New Delhi)