| With the rapid development of society and technology, the environment problem is mounting. As a result, it is important for us to recycle the precious metals from the mineral wealth and the rubbish arised by the industrial production and human life. Potato pulp is a kind of byproduct in the process of potato starch production, Potato pulp is not only much nourishment in various functional substance, but also contains higher value of exploitation and use. However,Potato pulp has been seldom made use of to advantage. For example it is usually used for Fodder and Fertilizer. And, the seirous environmental pollution is caused by rotten potato pulp due to hard store and transport and to dehydration. In order to solve the problem of exploitation and utilization of potato pulp, sodium hexametaphosphate (SHMP) as a chelating agent used to extract soluble dietary fiber (SDF) from potato pulp in this study. Moreover, the composition and properties of SDF are discussed comprehensively and systematically to broaden the application field and enhance its auxiliary value. In addition , the technology of centrifugal reelect and directly cyanogenation was applied to recycle and utilize the associated gold and silver in the copper deposit to raise the utilization rate of precious metal and reduce the resources waste.In the present essays, firstly, based on the summary of the structure and properties of the SDF, we make an introduce advance for extracting the SDF from the SHMP. Secondly, the method extracting the SDF from the SHMP was studied by the chelation used the sodium hexametaphosphate (SHMP) as a chelating agent. Moreover, through orthogonal experiments and single factor and experiments analysis of variance, we fixed the optimal conditions for extracting the SDF. The extraction percent of SDF was achieved58%.Thirdly, the surface topography and composition of SDF were analyzed by IR, SEM, Analysis of Elements and biochemical reaction. Meanwhile, the water-solubility, expansibility, retention ability and ion-exchange ability of SDF were investigated.The soluble dietary fiber in Potato pulp exhibited good solubility in water (56.15%), the high expansibility (8.56 mL/g) and water-holding capacity (7.72 g/g) reached the highest under pH = 7 and 37 ?C. Fourth, We reelected raw ore whichthrough 200 mesh occupied 60% by using 12 inches Nielsen MD3 centrifugal heavy separator and 12 inches domestic centrifugal heavy separator. It was found that the production efficiency and stability of domestic centrifugal heavy separator was favorable, therefore, it can be used in industrial production. The optimum conditions were determined by means of single factor experiment. The details as below, 800 rpm of centrifugal force, 20 L/min of recoil hydraulic and 120 min of accumulation time uninterruptedly run 60 h. The amount of obtained gold concentrate is 150 kg. The average gold grade is 671 g/t. The recovery is 52.21% and enrichment ratio is 583 in concentrate.Fifth, the high content of associated silver was extracting from the Copper Concentrate by cyanogenation Leaching Procedure. In order to raise the utilization rate of NaCN, we control the instantaneous speed of NaCN dropill by dropping. The results showed that the leaching rate of silver was more than 70% with the 48 hours of reaction time and the consumption of NaCN greater than 20 kg/t. Key words: Potato Pulp, soluble dietary fiber, centrifugal re-election, Copper concentration, Gold extraction, Silver extraction.
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