India generates around 170,000 tonnes per day of municipal solid waste (MSW). Of this, 70-75 per cent of MSW generated in urban India is collected while only 20-28 per cent is scientifically processed, as per the Ministry of Environment, Forest and Climate Change. The MSW generation is expected to increase from 62 metric tonnes (mt) at present to 165 mt annually by 2031, and the land requirement for setting up landfills for the next 20 years could be as high as 66,000 hectares. Many resources such as petroleum, plastics, iron and steel, and copper, which are contributing to the GDP and the import bill, also have large shares in MSW generation in the country.
The major drivers of waste management have been government regulations, landmark decisions and programmes on environmental and social awareness. In 2000, the MSW rules were introduced. In 2016, various rules such as solid waste management rules, biomedical waste management rules and e-waste management rules were also introduced. In 2021, the draft regulations for extended producer responsibility were prepared and the Swachh Bharat Mission 2.0 and AMRUT 2.0 were launched.
In the past 30-40 years, there have been significant advances in water treatment technologies that produce potable water. The challenge in the coming years will be related to wastewater reuse. To accelerate India’s circular economy shift, the focus needs to be on substituting wasted resources, monetising the wasted capacity, increasing the span of waste life cycles and recovering the embedded values. The 11 focus areas identified by NITI Aayog to expedite the transition from a linear to a circular economy include municipal solid and liquid waste, electronic waste, and lithium-ion batteries.
MSW management
Gujarat International Finance Tec-City (GIFT City) has been included as a model city in the greenfield category in the Government of India’s Smart City Mission Statement and Guidelines for the development of 100 smart cities in India. Some of the unique technologies adopted by GIFT are utility tunnels, automatic waste collection systems, district cooling systems and potable water from any tap throughout the city. The advantages of an automated waste collection system include 24×7 accessibility to the user, a clean and attractive city, less noise and reduced air emissions due to reduced transport needs, and a better working environment for waste collectors.
Chhattisgarh and Kerala are the two states where all households in all wards have successfully adopted the practice of waste segregation. Amongst the union territories, Daman and Diu & Dadra & Nagar Haveli have achieved 100 per cent source segregation.
Waste-to-energy
Commercial and industrial waste is an important source for producing solid waste fuels such as refuse-derived fuel (RDF) and solid recovered fuel (SRF). It is an eco-friendly alternative to fossil fuels. Around 37 per cent of waste ends up as landfill, and waste treatment is a great investment for converting this waste into clean energy.
RDF is used for meeting electricity and heating requirements, while SRF has a higher calorific value and meets specific requirements. It is primarily used in cement kilns. About 1 tonne of RDF reduces carbon dioxide (CO2) emissions by around 700 kg and is up to 95 per cent efficient. The cement industry is thinking of ways to use SRF as it can provide significant savings on fossil fuels. Since cement production is responsible for 8 per cent of the world’s CO2 emissions, greener cement production is a necessity. SRF can replace 30 per cent of fossil fuels without major investments. It is the perfect replacement for fossil fuels as it has the same calorific value as coal and can be easily adapted to production. M&J Recycling is creating RDF in a two-step solution and converting non-recyclable materials to fuel. M&J Recycling ensures easy maintenance and homogeneous output quality with no downtime.
Asset management and remote monitoring
The Bhopal Smart City proposal envisages redevelopment-driven urban overhaul by unlocking suboptimally utilised land parcels while using internet of things (IoT) to drive citizen-centric innovations. Road sweeping machines have been dedicated to cater to a 200 km lane length covering the main roads of Bhopal. The smart multipurpose machines will help in the dry/wet cleaning of main roads. Bhopal Smart City Development Corporation Limited is implementing 12 solid waste transfer stations for MSW from various locations.
Various transfer station facilities have been provided including a weighing bridge, a boom barrier with radio frequency identification tags, manager rooms/guard rooms/toilets/water coolers and accessories, compactor machines, and hook loaders with capsules. In addition, 130 underground smart dustbins have been installed with a capacity of 3 cubic metres for the collection of MSW at 100 designated locations in Bhopal city. Smart dustbins alert officials when the bin reaches a certain threshold. The integrated command and control centre has achieved 90 per cent financial progress. Sensors have been installed. The physical infrastructure set-up has been completed while application integration is still in progress. After the operationalisation of transfer stations, the garbage being dumped a the dumping yard has been brought down to 500-600 tonnes from 800 tonnes. To reduce fuel consumption, all the vehicles are mapped to the transfer stations.
Treatment technologies and decentralised facilities
The treatment processes that are being practised at present are conventional treatment technologies for primary and secondary treatment. Secondary treatment includes biological conversion of dissolved organics to biomass, subsequent removal by sedimentation, suspended growth such as activated sludge process, and attached growth such as a trickling filter. After the sludge is produced, it is intended to be properly and safely disposed of. This can be done by sludge thickening and digestion. Sludge thickening is a technique of volume reduction and digestion reduces the volume of the thickened sludge. After digestion, there should be no cellular end products. Effluent treatment includes filtration, carbon adsorption, phosphorous removal and nitrogen removal. The disposal of effluents is done by dilution in the surface waste, the evaporation system, ocean disposal, groundwater recharge, etc.
Decentralised treatment technologies have several advantages. They allow collection, treatment and disposal within the same locality. They present the best option for the recycling and reuse of wastewater, and can also optimise the cost of construction and the time period. They are preferred where there is scope for recycling/ agricultural land use as well as in areas where the depth of excavation is restricted. The treated wastewater can be used in the potable water system, industrial water supply, etc.
The factors driving the desalination market in India include increasing population, industrialisation, scarcity of potable water and demand for freshwater.
The challenges related to wastewater still faced in India include lack of awareness, lack of public-private partnerships in wastewater management, imbalance in the amount of wastewater and treatment plants, etc. Some of the issues being faced by private players are the absence of a policy framework, rotation of key managers, etc. Further, decision-makers and financial institutions do not have complete knowledge of the water management sector.
Opportunities galore
The opportunities in seawater desalination include large coastal areas, raw water requirements of mega power plants, and water treatment plants. The key energy consumers in wastewater treatment plants include aeration bioreactors, intake pumps, turnover digesters, return sludge pumps, scrappers, sludge thickening, among others. The major cost components of a pump are energy consumption (32 per cent), followed by maintenance and repair (20 per cent) and initial cost (10 per cent). In order to enhance the energy efficiency in piping systems, the focus should be on the characteristics of the liquid being pumped, roughness and length of the piping, bends, joints, valves in the pipeline, among others.
Going forward, the key drivers for growth in the waste management sector will be the increased focus on net zero commitments and environmental, social and governance investments as well as the shift to a circular economy. Also, appropriate policy measures to create awareness about the demand for waste can drive the waste management activity more effectively.
Based on inputs from the “Waste Management in India” conference organised by India Infrastructure
