Coals from different mines are feed in the Zirab plant without any control on weight percentage blending of them. Three major coal types of different ranks (Kiasar, Lavidj and Karmozd) were blended in various proporti...Coals from different mines are feed in the Zirab plant without any control on weight percentage blending of them. Three major coal types of different ranks (Kiasar, Lavidj and Karmozd) were blended in various proportions to find an optimum condition in flotation circuit in Alborz Markazi coal washing plant. Flotation tests were conducted for prepared blended coal samples to assess floatability of various coal samples. In this paper, mixture design as a statistical method was used to optimize coal blend to increase recovery and grade in Zirab coal washing plant. The statistical analysis showed that the weight percent blending of different coals and interaction between Lavidj and Karmozd regions coal had significant effects on the coal recovery. The optimum condition of 95% recovery and 12% ash content could be reached with 10%, 20%, and 70% blending portion of Kiasar, Lavidj and Karmozd regions coal, respectively.展开更多
Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has sho...Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in May 2010, to assess the effects of wheat straw(WS) and chicken manure(CM) biochars and compost with and without phosphorus(P) addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The CM and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases(P < 0.05) were no more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30%of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time.展开更多
文摘Coals from different mines are feed in the Zirab plant without any control on weight percentage blending of them. Three major coal types of different ranks (Kiasar, Lavidj and Karmozd) were blended in various proportions to find an optimum condition in flotation circuit in Alborz Markazi coal washing plant. Flotation tests were conducted for prepared blended coal samples to assess floatability of various coal samples. In this paper, mixture design as a statistical method was used to optimize coal blend to increase recovery and grade in Zirab coal washing plant. The statistical analysis showed that the weight percent blending of different coals and interaction between Lavidj and Karmozd regions coal had significant effects on the coal recovery. The optimum condition of 95% recovery and 12% ash content could be reached with 10%, 20%, and 70% blending portion of Kiasar, Lavidj and Karmozd regions coal, respectively.
基金supported by the Australian Centre for International Agricultural Research (ACIAR) Project (No.SMCN 2007/109)
文摘Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in May 2010, to assess the effects of wheat straw(WS) and chicken manure(CM) biochars and compost with and without phosphorus(P) addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The CM and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases(P < 0.05) were no more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30%of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time.
