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High quality in-situ compaction of municipal solid waste (MSW) is required to ensure landfill stability. However given the heterogeneous composition of MSW, it is important to assess the potential sensitivity of Dynamic cone penetrometers (DCP) and direct shear apparatus to changes in compaction effort, composition and aging effect and different specific work per blow of DCP on penetration resistance (DPI) and shear strength parameters of fresh and excavated Johannesburg landfill municipal solid waste. The results reveal that for average density range of 354kg/m3 to 722kg/m3 the mobilized penetration resistance, DPI was 15 - 40 mm/blow for DCP specific work per blow of 144 kJ/m2 and 10 - 33 mm/blow due to reduced work per blow of 92kJ/m2. The friction angle and cohesion of fresh waste and landfilled waste with fibrous content of 45% and 64% respectively are 19° and 12kPa for fresh waste and 21? and 31kPa for landfilled waste. 24 hours soaking of waste resulted in reduction in friction angle of fresh waste and cohesion of landfilled waste respectively. Controlling the ratio of sand, organics and fibrous content in recycling program is required to increase the stability of landfilled sites exposed to high tropical rainfall. [ABSTRACT FROM AUTHOR]

Composting is gaining popularity as a sustainable means for the recycling of organic waste, and this technique has positive implications for water quality protection, waste management, and sustainable farming. However, the nutrient content of compost, particularly compost made from municipal solid waste (MSW), is often not sufficient for use in large-scale agriculture. Therefore, the conservation of nitrogen in composting is a subject of current research interest. In this study, compostible MSW materials (yard trimmings and food scraps) were treated in pilot-scale batch reactors. Various process modifications and improvement techniques were tested in pilot-scale batches. The addition of shredded paper, strong acid, or acid-loaded bentonite clay to the batches all proved to be successful in increasing nitrogen concentrations by 25% to 125% compared to unmodified control batches. The collection of compost leachate also appears to be a viable technique to conserve nitrogen in MSW composting. [ABSTRACT FROM AUTHOR]

In this study a total of 183 soil samples, 5kg each, were collected from the University of Tripoli Agriculture Experiment Station. Triplicates of 26 treatment combinations consist of air dried seaweed (SW), partially decomposed municipal waste (MW) and sewage sludge (SS), each grounded to pass 0.5 cm sieve were prepared to get mixed application rate of 20 t/ha. Other triplicates of 35 treatment combinations were prepared similarly to get mixed rate of 40 t/ha. One hundred kg/ha of 12-24-12 mixed fertilizer was added to each treatment. All treatments were incubated in a controlled moisture (50% of FC) and temperature (25 ±2 °C) greenhouse compartment for four months. At the end of this period some chemical and microbiological analyses were conducted. Tomato (Rio Grande) seedlings were planted and let grow for four months during which care was taken of keeping moisture and temperature as indicated earlier whilst number of leaves and plant heights were recorded periodically each month. At the end of the experiment the above aerial portions of the plants were separated from the roots and put in separate punched paper envelopes and dried at 60 °C for two days. The dried weights were recorded. The results indicated that there was no tangible difference between the 20t/ha and the 40t/ha combination treatments. The combined dry weight (roots + aerial portions) ranged from 7.65- 19.73 g/pot with an average of 11.94 g/pot in the 20 t/ha experiment. With regard to the 40 t/ha experiment, the combined dry weight ranged from 1.67-19.83 g/pot with an average of 11.10 g/pot. In both experiments, the dry weights in seven different combination treatments were higher than the control treatment (soil alone). [ABSTRACT FROM AUTHOR]

Sustainable development and the Triple Bottom Line integrated sustainability concept focus on the choices between the imperatives of economic efficiency, social development and environmental sustainability. Effective waste management and reduction is a global concern as volumes of waste generation are increasing every year. Many countries, with developing countries being far worse off, face challenges in providing effective waste management practices within their countries due to the insufficient funds, lack of capacity, human expertise and waste management facilities and equipment. Corporate governance is being imposed by stakeholders and corporate social responsibility is indicated as being the most important socio-environmental demand being made on contemporary leaders. The influence of idealism and realism on, and the reasons for failure of, solid waste reduction projects in terms of sustainability is the foundation of the theories postulated in this research. It is the objective of this research to identify the motivational factors, with special reference to developing countries, of social capital, including management processes leadership and people management, that will augment solid waste reduction projects that are lethargic at starting, or deteriorating, to achieve sustainability. The criterion for the research sample is to obtain the opinions of environmental specialists in South Africa using a questionnaire. The technique employed is multivariate data analysis to identify the type of interdependent relationships, including cluster and multidimensional scaling analyses. Hypothesis testing, in this research, leads to the conclusion that additional motivational factors are needed to support the economic imperatives to make the process sustainable. 'Reality' is statistically significantly different to 'idealistic'. The inference is that for solid waste reduction projects to succeed leaders from government and the private sector are required, through the use of legislation and taking into consideration the value of waste, to instil economic incentives. According to this research, personal values and belief systems have little to contribute to the process of sustainability. The outcome of this research provides a strategy-benchmarking model that leaders can use to target and prioritise their efforts in respect of achieving success with waste projects. The contribution it makes to the knowledge base of the subject and responsible leadership is contained in its summation of the augmenting factors required, their relative importance, and the lessening of the complexity of approach to these projects. [ABSTRACT FROM AUTHOR]

For waste disposal there exist basically the options for landfilling, incineration, anaerobic digestion and at its early stages pyrolysis. All of them have a number of disadvantages which involve costly compromises: - Landfilling apart from being a big waste of resources is the source of uncontrolled methane emissions, and methane is a very powerful global warming gas. Accordingly landfilling of organic wastes has been banned already in many countries. - Incineration is certainly the least acceptable option for disposal of municipal solid waste. It has high investment costs which usually require high tipping fees, which many countries are not ready to spend - Anaerobic digestion has started to become accepted as a clean and environmentally acceptable alternative, but efficiency is low - Pyrolysis is still a new technology; it can accept a wide range of unsegregated input materials and offers high energy efficiency. However the generated synthesis gas always contains tar which sooner or later require costly maintenance of the CHP generator The German company Solventure has developed an alternative, the so called DLE technology, which avoids the mentioned disadvantages and has the potential to substitute all of the above listed technologies. What are the advantages of the DLE alternative: The unsegregated waste is dissolved in a salt solution at moderate process conditions of 200 °C, 6 bar and broken down into an energy-rich watery solution of organic salts. This slurry is gasified into a clean, tar-free synthesis gas (H2 + CO). The gas is subsequently converted in a CHP unit into electricity and heat. Toxic ingredients (halogens) are buffered into insoluble salts and eliminated together with the mineralic fraction (sand, glass etc.) as sediment. So a very simple emission-free process of only three stages with limited investment costs and high electricity output (and heat if a consumer is available). The process accepts all"soft" waste as input (organics + plastics) without any presorting, moisture is not an issue, no pre-drying is required. Costs of generated electricity including depreciation are in the order of 0,06 US$/kWh. Additional income is usually available from gate fees for the waste input and from sale of Carbon emission certificates (renewable energy!). The conversion of the input material into a liquid slurry at an early process stage allows easy automation. In liquid stage also chemical processes such as precipitation, buffering etc. are possible which allow separation of valuable chemicals which usually allow even higher revenues than just energy conversion. [ABSTRACT FROM AUTHOR]

For waste disposal there exist basically the options for landfilling, incineration, anaerobic digestion and at its early stages pyrolysis. All of them have a number of disadvantages which involve costly compromises: - Landfilling apart from being a big waste of resources is the source of uncontrolled methane emissions, and methane is a very powerful global warming gas. Accordingly landfilling of organic wastes has been banned already in many countries. - Incineration is certainly the least acceptable option for disposal of municipal solid waste. It has high investment costs which usually require high tipping fees, which many countries are not ready to spend - Anaerobic digestion has started to become accepted as a clean and environmentally acceptable alternative, but efficiency is low - Pyrolysis is still a new technology; it can accept a wide range of unsegregated input materials and offers high energy efficiency. However the generated synthesis gas always contains tar which sooner or later require costly maintenance of the CHP generator The German company Solventure has developed an alternative, the so called DLE technology, which avoids the mentioned disadvantages and has the potential to substitute all of the above listed technologies. What are the advantages of the DLE alternative: The unsegregated waste is dissolved in a salt solution at moderate process conditions of 200 °C, 6 bar and broken down into an energy-rich watery solution of organic salts. This slurry is gasified into a clean, tar-free synthesis gas (H2 + CO). The gas is subsequently converted in a CHP unit into electricity and heat. Toxic ingredients (halogens) are buffered into insoluble salts and eliminated together with the mineralic fraction (sand, glass etc.) as sediment. So a very simple emission-free process of only three stages with limited investment costs and high electricity output (and heat if a consumer is available). The process accepts all"soft" waste as input (organics + plastics) without any presorting, moisture is not an issue, no pre-drying is required. Costs of generated electricity including depreciation are in the order of 0,06 US$/kWh. Additional income is usually available from gate fees for the waste input and from sale of Carbon emission certificates (renewable energy!). The conversion of the input material into a liquid slurry at an early process stage allows easy automation. In liquid stage also chemical processes such as precipitation, buffering etc. are possible which allow separation of valuable chemicals which usually allow even higher revenues than just energy conversion. [ABSTRACT FROM AUTHOR]

Dumps of residential solid waste (RSW) has been visible in the districts of Mosul City long time before the 2003 war. Moreover, in some districts, residents and others take their solid waste to the banks of River Tigris, causing further pollution to this relatively large and fast flowing river. The Directorate of Mosul Municipality (DMM) is doing what it can to provide a sort of minimum collection, transfer, and disposal services to the city. When the funding for these services dries up, dumps of RSW (and other solid waste) become more visible. Having no reliable and detailed data on RSW generation for Mosul City and its districts to bite on, the DMM had to rely on the unrealistic RSW generation rate of one kilogram per capita a day (kg/capita/day) for planning and budgeting purposes. This mini-project attempts at bringing the 0MM closer to such data, using a sample survey. The estimated RSW generation rate at source for Mosul City, using the survey data, has been around 0.3kg/capita/day. With an estimated city population of 1.2 million or so, RSW generation would be some 400 tons a day. The study includes, among other things, RSW generation for each municipal section of Mosul City, and containers need for twelve of its districts. The author concludes the study with some recommendations. [ABSTRACT FROM AUTHOR]

As English local authorities develop strategies to deal with the growing volumes of municipal waste created in their districts, householder participation in recycling initiatives is becoming increasingly important Taking a social dilemma perspective, this paper adopts an individual (psychological) strategy as a means of enhancing kerbside recycling use in the London Borough of Havering. Three groups of householders received motivational messages on recycling performance with a different bias: critical, neutral or encouraging, whilst a further group acted as a control. Although differences in recycling behaviour prior to and following intervention were not statistically significant for any treatment group, average use of the scheme was found to decrease post-leaflet in all cases, but less so for those in the 'encouraging' message group, Responses to a questionnaire survey indicated that householder attitudes did not vary significantly between treatment groups. The study shows that an individual (psychological) approach alone is riot sufficient to enhance householder recycling behaviour in Havering over the short term. Future promotional strategies are suggested that combine both the individual arid the collective approach to motivate and encourage recycling participation. [ABSTRACT FROM AUTHOR]