摘要
本文收集了全国36个矿区67个磷矿标本和全国30个主要磷肥厂的磷肥样品,对其含镉量进行了分析和评价。67个磷矿含镉量范围为0.1—571mg kg^(-1)Cd,平均为15.3±74mg kg^(-1)。如果除去广西等四个贮量较小但含镉较高的矿区,其余矿区磷矿平均含镉为0.98mg kg^(-1) Cd。30个磷肥样品平均含镉0.60±0.63mg kg^(-1) Cd,变幅为0.1—2.93mg kg^(-1)。其中普钙平均为0.75±0.65mg kg^(-1) Cd,钙镁磷肥为0.11±0.03mg kg^(-1) Cd。热法磷肥在生产过程中含镉量因挥发而降低。根据我国磷肥通常用量和作物吸镉特点,认为长期施用国产磷肥,不至产生污染环境问题。
Total 67 rock phosphate samples collected from 36 phosphate deposits and 30 phosphate fertilizer samples from main phosphate plants of China were studied.The content of Cd in rock phosphates from different deposits varied from 0.1 to 571mg/kg, with an average value of 15.3±74mg/kg. The highist value was found in the rock phosphates from Guangxi Province, varying from 12.2 to 571mg/kg; while the lowest Cd content of the rock phosphates from Hubei Province varied from less than 1 to 2.10 mg/kg. Fortunately. all the phosphate deposits of high Cd content are of less importance in the phosphate fertilizer production of China. If not counting these minor important but high Cd content phophate rocks the average Cd content of phosphate rocks of China should be 0.98 mg/kg.The Cd content of phosphate fertilizers collected from 30 plants of China ranged from 0.1 to 2.93mg/kg, with an average of 0.60±0.63mg/kg. It is very interested that the Cd contents. of all the Ca-Mg phosphate fertilizer samples collected were quite low which are only 15% of those of superphosphates with an average Cl content of 0.11±0.03mg/kg. The lower Cd content as compared with superphosphate is due to Cd volatilization at high temperature during processing.The phosphate fertilizers consumed in China in 1989 amounted to 4.189 million tons of P_2O_5. Total amount of Cd brought into soil with phosphate fertilizer was about 16.8 tons Cd in that year. This was equivalent to about 0.3g per hectare of arable land.The maximum soil environmental capacity for Cd of differnet soil types was calculated. It ranged from 0.73kg Cd/ha (for acid upland soil) to 6.36kg Cd/ha (for calcareous paddy field). From these data it is believed that the problem of cadmium pollution due to long-continued application of phosphate fertilizer might not be expected.
出处
《土壤学报》
CAS
CSCD
北大核心
1992年第2期150-157,共8页
Acta Pedologica Sinica
关键词
磷肥
磷矿
镉
生态环境
Cadmium, phosphate fertilizers, Phosphate rock
