Influence of undergraduates activities on the waste composition and generation rates in a residential University – case study

The increase of waste generation and its disposal is a major problem and challenge faced by the most of the countries today.The uncontrolled disposal of different types of waste into environment is a great threat for the future of all living beings in the world. Therefore, it is essential to pay more attention for the waste management and disposal to avoid the detrimental impact on the environment. For the development of a proper treatment or disposal systems for waste management for any organization or municipality, it is essential to have the information with respect to waste composition, generation rate and its variation with time of that organization. Therefore, in this study, it was attempted to evaluate the composition and the variation of waste generation rate in the hostels of the undergraduates of University of Ruhuna with their activities.The study was conducted in the premises and surroundings of the hostels of the undergraduates for a period of one year (September to August). The waste samples were collected from each and every hostel once in two months. The waste samples were separated into different components (such as foods, paper, plastics, etc), weighed and determined the percentages of different components.  The different types of waste generation rate per head were calculated based on the waste generation for the total study period. It was found that food remains, papers, plastics and polythene are the major components. The types of waste found in hostels of girls were less in numbers than that of boys. Leather, textiles, metals, etc could not be found in hostels of girls.Over ~95 % of waste found in girls’ hostels were food remains and boys generate food waste about ~71%. Per capita food waste generation by girls was ~ 207 g/day while it was ~23 g/day by boys. The generation of other types of waste was higher in hostels of boys than that of girls’ hostels. It appears that the amount of waste generation varied in different months basically due to examinations and other activities of the students. During examination periods, it seems that the undergraduates may change their food habits. Based on this study, it can be concluded that major component of waste found in undergraduate hostels was food wastes and the generation rate slightly varies with the activities of undergraduates. When designing of a waste management systems for higher education institutes where students reside, higher priority should be given for the management of food wast

Mitigation strategies of hydrogen sulphide emission in sewer networks - A review

Hydrogen sulphide (H2S) gas emission in sewer networks is associated with several problems including the release of dangerous odour to the atmosphere and sewer pipe corrosion. The release of odour can endanger public health and corrode sewer pipe walls. Sewer corrosion has the potential to cost water utilities millions of dollars to maintain and rehabilitate the affected sewer pipes. Some chemical mitigation strategies to control hydrogen sulphide emission have been introduced. These include but are not limited to the injection of oxygen, magnesium and sodium hydroxide, calcium nitrate and iron salts. The optimisation of the dosing rate and location of each chemical mitigation strategy is required to achieve maximum hydrogen sulphide gas removal efficiency along with cost effectiveness. In this review paper, the five most popular chemical mitigation strategies that were previously mentioned have been investigated and discussed. The article is broken down into three main discussions. Firstly the sewer transformation processes and factors affecting the hydrogen sulphide generation and emission are highlighted. Secondly, comparisons and differences between each selected chemical mitigation strategy as well as its application covered. Finally, the review of the chemical efficiency and cost is conducted by comparing two case studies in controlling the formation of dissolved sulphide. It was found that the injection of oxygen is the cheapest mitigation strategy of hydrogen sulphide gas generation in sewers, but least effective

Postharvest Losses, Food Safety and Value Chain of Fruit and Vegetables in Sri Lanka for the Fruit and Vegetables for Sustainable Healthy Diets Initiative

This report by FRESH initiative partner University of Sydney, with collaborator Industrial Technology Institute of Sri Lanka, is a characterization of the fruit and vegetable value chain in Sri Lanka. This report is a synthesis of a literature review on postharvest management, with special emphasis on loss assessments, research and innovation, of fresh fruits and vegetables; a literature review on food safety, with special emphasis on food microbiology, such as the testing of pesticide residues on fresh vegetables; and a series of target key stakeholder interviews. This report identifies evidence gaps and areas for intervention and collaboration with many actors along the fruit and vegetable value chain

Profiling of amino acids in traditional and improved rice (Oryza sativa L.) varieties of Sri Lanka and their health promoting aspects

Investigation made on the variation in amino acid compositions among selected traditional and newly improved rice varieties cultivated in Sri Lanka is presented. The free amino acid (FAA) composition including gamma-amino butyric acid (GABA) and protein bound total amino acids (TAAs) of eleven traditional and seven improved rice cultivars grown at Batalagoda across the two major cultivating seasons in the country were evaluated. Significant variations (p < 0.05) in GABA levels, individual and total amino acids in free and protein bound form were observed among the studied varieties. Both traditional and improved varieties reported comparable mean total FAAs and TAA levels. However, significantly higher levels of GABA, which has health promoting functional properties, were found in newly improved rice varieties in comparison to the traditional varieties. Significant impact of seasonal variation on total amino acid levels was observed in majority of the varieties with most of the varieties reporting higher amino acid levels when cultivated during the “Maha”, which is the major cultivation season in the country. The Behethheenati rice out of the traditional, while Bg 300 rice out of the newly improved, was found the most beneficial among the investigated varieties. The potential significant contribution obtainable with several local traditional and improved varieties in fulfilling the majority of the recommended essential amino acid nutrient requirement in the daily diet by the world health organization is highlighted

Problems in seawater industrial desalination processes and potential sustainable solutions: a review

Seawater desalination has significantly developed towards membrane technology than phase change process during last decade. Seawater reverse osmosis (SWRO) in general is the most familiar process due to higher water recovery and lower energy consumption compared to other available desalination processes. Despite major advancements in SWRO technology, desalination industry is still facing significant amount of practical issues. Therefore, the potentials and problems faced by current SWRO industries and essential study areas are discussed in this review for the benefit of desalination industry. It is important to consider all the following five components in SWRO process i.e. (1) intake (2) pre-treatment (3) high pressure pumping (4) membrane separation (performance of membranes and brine disposal) and (5) product quality. Development of higher corrosion resistant piping materials or coating materials, valves, and pumps is believed to be in higher research demand. Furthermore, brine management, that includes brine disposal and resource recovery need further attention. Pre-treatment sludge management and reduced cleaning in place flush volume will reduce the capital costs associated with evaporation ponds and the maintenance costs associated with disposal and transportation reducing the unit cost of water