Report on fisheries invertebrate survey of the Groove Beck,Thornsgill Beck,Troutbeck system

This is the Report on fisheries invertebrate survey of the Groove Beck, Thornsgill Beck and Troutbeck system produced by the Environment Agency North West in 1997. In 1996 the National Rivers Authority (NRA) report on the 1992 strategic stock assessment for the Upper Derwent catchment Jane Atkins recommended that should subsequent electrofishing show continued low densities, a survey of the invertebrate fauna should be undertaken to assess the food availability for salmonids, in order that lack of food could be ruled out as a contributory factor in their poor breeding success. Additionally the survey looked at the substrate to try to determine whether the bed type might actually be unsuitable for spawning, especially in view of the previously mentioned silt inputs.

Carp seed production during drought year 1987 under controlled hatchery system

The introduction of the controlled hatchery system "Model CIFE D-81" resulted in a production of 60 lakhs Indian major carp seed in the drought area of eastern Uttar Pradesh. The hatchery system provided optimum temperature, dissolved oxygen and pH for breeding and hatching and also removed the metabolites generated. The technology is simple and the success of the program attracts pisciculturists.

Optimization of flocculation process and continuous filtration for sea water primary treatment filtration to reduce SDI for entree to reverse osmosis system

Today , Providing drinking water and process water is one of the major problems in most countries ; the surface water often need to be treated to achieve necessary quality, and in this way, technological and also financial difficulties cause great restrictions in operating the treatment units. Although water supply by simple and cheap systems has been one of the important objectives in most scientific and research centers in the world, still a great percent of population in developing countries, especially in rural areas, don't benefit well quality water. One of the big and available sources for providing acceptable water is sea water. There are two ways to treat sea water first evaporation and second reverse osmosis system. Nowadays R.O system has been used for desalination because of low budget price and easily to operate and maintenance. The sea water should be pretreated before R.O plants, because there is some difficulties in raw sea water that can decrease yield point of membranes in R.O system. The subject of this research may be useful in this way, and we hope to be able to achieve complete success in design and construction of useful pretreatment systems for R.O plant. One of the most important units in the sea water pretreatment plant is filtration, the conventional method for filtration is pressurized sand filters, and the subject of this research is about new filtration which is called continuous back wash sand filtration (CBWSF). The CBWSF designed and tested in this research may be used more economically with less difficulty. It consists two main parts first shell body and second central part comprising of airlift pump, raw water feeding pipe, air supply hose, backwash chamber and sand washer as well as inlet and outlet connections. The CBWSF is a continuously operating filter, i.e. the filter does not have to be taken out of operation for backwashing or cleaning. Inlet water is fed through the sand bed while the sand bed is moving downwards. The water gets filtered while the sand becomes dirty. Simultaneously, the dirty sand is cleaned in the sand washer and the suspended solids are discharged in backwash water. We analyze the behavior of CBWSF in pretreatment of sea water instead of pressurized sand filter. There is one important factor which is not suitable for R.O membranes, it is bio-fouling. This factor is defined by Silt Density Index (SDI).measured by SDI. In this research has been focused on decreasing of SDI and NTU. Based on this goal, the prototype of pretreatment had been designed and manufactured to test. The system design was done mainly by using the design fundamentals of CBWSF. The automatic backwash sand filter can be used in small and also big water supply schemes. In big water treatment plants, the units of filters perform the filtration and backwash stages separately, and in small treatment plants, the unit is usually compacted to achieve less energy consumption. The analysis of the system showed that it may be used feasibly for water treating, especially for limited population. The construction is rapid, simple and economic, and its performance is high enough because no mobile mechanical part is used in it, so it may be proposed as an effective method to improve the water quality and consequently the hygiene level in the remote places of the country.