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The USA, China and India are the top three producers of municipal solid waste. The composition of solid wastes varies with income: low-to-middle-income population generates mainly organic wastes, whereas high-income population produces more waste paper, metals and glasses. Management of municipal solid waste includes recycling, incineration, waste-to-energy conversion, composting or landfilling. Landfilling for solid waste disposal is preferred in many municipalities globally. Landfill sites act as ecological reactors where wastes undergo physical, chemical and biological transformations. Hence, critical factors for sustainable landfilling are landfill liners, the thickness of the soil cover, leachate collection, landfill gas recovery and flaring facilities. Here, we review the impact of landfill conditions such as construction, geometry, weather, temperature, moisture, pH, biodegradable matter and hydrogeological parameters on the generation of landfill gases and leachate. Bioreactor landfills appear as the next-generation sanitary landfills, because they augment solid waste stabilization in a time-efficient manner, as a result of controlled recirculation of leachate and gases. We discuss volume reduction, resource recovery, valorization of dumped wastes, environmental protection and site reclamation toward urban development. We present the classifications and engineered iterations of landfills, operations, mechanisms and mining. [ABSTRACT FROM AUTHOR]

Paper industries using different raw materials such as hard wood, bamboo, baggase, rice-straw and waste papers and bleaching chemicals like chlorine, hypochlorite, chlorine dioxide, hydrogen peroxide, sulphite and oxygen were studied to estimate organic pollution load and Adsorbable Organic Halides (AOX) per ton of production. The hard wood based paper industries generate higher Chemical Oxygen Demand (COD) loads (105–182 kg t−1) and Biochemical Oxygen Demand (BOD) loads (32.0–72 kg t−1) compared to the agro and waste paper based industrial effluents. The bleaching sequences such as C–EP–H–H, C–E–H–H, C–E–Do–D1 and O–Do–EOP–D1 are adopted in the paper industries and the molecular elemental chlorine free bleaching sequence discharges low AOX in the effluent. The range of AOX concentration in the final effluent from the paper industries was 0.08–0.99 kg t−1 of production. Water consumption was in the range of 100–130 m3 t−1 of paper production for wood based industries and 30–50 m3 for the waste paper based industries. Paper machine effluents are partially recycled after treatment and pulp mill black liquor are subject to chemical recovery after evaporation to reduce the water consumption and the total pollution loads. Hypochlorite bleaching units of textile bleaching processes generate more AOX (17.2–18.3 mg l−1) and are consuming more water (45–80 l kg−1) whereas alkali peroxide bleaching hardly generates the AOX in the effluents and water consumption was also comparatively less (40 l kg−1 of yarn/cloth). [ABSTRACT FROM AUTHOR]

We analyse the results from a longitudinal natural field experiment that provides an environmental nudge by reinforcing positive environmental norms. Posters asking individuals to use less paper are pasted on printers (Times) and in office cubicles (Umendall) of two information technology firms around New Delhi, India. A third firm (India Mart) does not get the nudge and serves as our control. During the nudge period, employees of the firms that get the conservation message on average expend a significantly lower number of sheets per day as compared to the pre-nudge period, measured both in terms of paper used and paper wasted. Furthermore, after the nudge is removed, the per capita paper wastage for one of the firms that received it (Times) does not increase significantly over the next month and a half, whereas for the other firm (Umendall) it does but remains significantly lower than the per capita wastage in the pre-nudge period. In terms of total paper used, the nudged firms show a reduction in the number of sheets used several weeks after the nudge is removed. For the control firm, the wastage and usage of printer paper does not change significantly over the duration of the experiment. A robustness check with no nudge intervention done by computing per capita wastage and usage for the same dates exactly one year later does not show a reduction over the same time period and offers support for our conclusions. [ABSTRACT FROM AUTHOR]

A comprehensive case study of Mumbai (Bombay), India was undertaken to investigate the economic, social and environmental impact of international trade of waste paper for recycling purposes between industrialized and developing countries. Analysis of a Western approach vis-a-vis informal policy for waste paper recovery concludes that employment is maximum under informal policy measure and public response playsan important role in maintaining environmental quality. The study further shows that income inequality is more under informal policy, andwithout policy public cost will increase continuously in the future.The net present value of the informal policy is found to be higher than that for the formal policy. Econometric study on input substitution in the Indian paper industry suggests limited substitution possibilities between domestic and imported waste paper. Results from a static material balance flow model indicate that environmental impacts are less with increased trade and economically the paper sector in India benefits from free trade. Based upon the results of the study, somepolicy recommendations have been made that may enhance the efficiency of waste paper recycling in India. [ABSTRACT FROM AUTHOR]