Recycling of aluminum chips by hot extrusion is a metal forming technique, which requires considerably less energy than conventional recycling by remelting. The aluminum chips sorted by alloy type were first chemically washed in a mid-alkaline bath and then completely dried in an industrial furnace, compacted to billets, heated up to extrusion temperature and directly extruded into finished products without remelting. This method utilizes not only significantly less energy compared to conventional recycling by remelting but also prevents the material loss that is typical in remelting of fine aluminum scrap in the form of chips.The main aim of this research was to investigate hot extrusion of aluminum chips including principles of operation, process technology and equipment, and to develop this process further by solving the encountered problems to allow its application in industry. First the effect of extrusion process parameters on the microstructure and mechanical properties of the profiles recycled from chips was investigated. It was shown that the extrusion parameters like extrusion ratio, die design and the billet temperature predominantly define the properties of the recycled profiles. The mechanism of chip welding during aluminum extrusion was investigated using the analysis of the microstructural evolution. Based on the analytical solutions for the problem of longitudinal seam weld formation, a new approach was developed to analyze the welding of the aluminum chips. The boundary conditions for sound chip welding can be defined using the proposed analytical approach as well as with the help of simulations using the finite element method (FEM). A welding-quality-index (WQI) is introduced to define the chip welding quality under given process conditions, which can be used to quantitatively evaluate the success of recycling aluminum chips by hot extrusion. An innovative process design utilizing a closing cap and a new punch design was developed to eliminate the formation of air blisters during hot extrusion of chips.
Wetlands are vital water bodies, as crucial in a natural ecosystem as kidney in a human body. Apart from being highly productive as the habitat of birds, fishes and a variety of other aquatic life forms-micro-organisms. Wetlands provide other ecosystem services from maintaining the natural balance and for sustaining human livelihoods. Overall wetlands all over the country are exhibiting varying degrees of environmental degradation caused by encroachments, Eutrophication, siltation, urbanization and anthropogenic activities. There is also a misconception that wetlands are only wastelands. As a result, many precious wetlands have been converted to other uses all over in the world. Highly adaptable solutions must be found to permit development activities, including tourism,subsistence agriculture, and conservation of wildlife to be each given a fair share' of the one biome the wetland. This book provides an overview of the wetland study including flora, avifauna, management and restoration measures. It contains methodology of avifaunal survey, water quality analysis and WQI. It should be especially useful to those who are working in the field of wetland and environment conservation.
Water quality indices (WQI) were introduced aiming at giving a single value to the water quality of a source, thus reducing great amount of parameters into a simpler expression . In this book, an attempt has been made to devise a methodology to analyse various water quality parameters and then integrate them with WQI and Geographic Information System (GIS) for an effective interpretation of the quality status of groundwater by taking Delhi as a case study. Physical and chemical analysis of groundwater of Delhi was conducted and results interpreted using WQI and finally translated in sensitivity maps using GIS. The book delves in understanding water quality assessment and should be useful for anyone interested in groundwater quality issues from general public and students to policy makers.
The research presents water quality analysis of Bhadravathi in Karnataka State, India. Fourteen physico-chemical and biological parameters were considered for the analysis. The raster maps created using GIS are used to represent the spatial distribution of the parameters for both pre and post-monsoon seasons. Using physico-chemical parameters, Water Quality Index (WQI) was determined. The WQI shows 11% of the surface water samples fall under very good category during pre-monsoon and 78% in post-monsoon. The water sample at New Bridge site shows sign of pollution throughout year with WQI in the range 50-100 and hence unfit for use. In groundwater samples, 20% of samples in the pre-monsoon and 50% samples during post-monsoon fall under good quality. 50% of water samples during pre-monsoon and 60% of samples during post-monsoon fall under good category and water sample at Haladamma temple are found unfit. Further, QUAL2K model predicted the DO and BOD values considerably well along the Bhadra River from Lakkavalli to Bhadravathi Town. However, the Streeter Phelp s model estimated higher DO as compared to QUAL2K model. This is due to provision of outfall effect in Streeter Phelp s model.
The Book 'Waste Water Irrigation' is an out-come of researches of about 5 years. Waste water is a great problem in developing countries like India. The waste water in India is generated through a variety of sources and its proper disposal is not an easy task. On the other hand lots of groundwater is wasted for irrigation, particularly for vegetables, which are mostly grown in the sub-urban area. Due to enormous pumping of water by the urban population in addition to the run off loss through vegetable irrigation, the water table occasionally falls abruptly in urban area, particularly during summers. In addition solanaceous vegetables are the most prominent food stuff, which is used round the year. Therefore, series of experiments were conducted through irrigating solanaceous vegetables by sewage. WQI of the sewage water and its suitability was also studied. The yield and nutrient analysis of the harvest was explored and compared to that of the crop irrigated by normal water. Satisfactory results were obtained. The book is supposed to be useful to all, involved in the researches of environment, may be from the discipline of Botany, Zoology, Geography, Biochemistry, Engineering etc.