四株黑曲霉对高磷铁矿脱磷的研究

研究了四株不同来源的黑曲霉对高磷铁矿的脱磷作用,结果表明,在NBRIP培养基中,四株黑曲霉都能有效脱除高磷铁矿中的磷,但脱磷效率存在一定的差异,脱磷率从高到低依次为WIT-4>WIT-3>WIT-2>WIT-1。分析了四株黑曲霉对高磷铁矿的脱磷机制,发现黑曲霉生长代谢产生有机酸使体系可滴定酸浓度增加及pH下降是其脱磷的主要原因。     

A Novel Approach to Bioleach Soluble Phosphorus from Rock Phosphate

A novel approach to bioleach soluble phosphorus from rock phosphate, involving the bio-oxidation of pyrite by adaptated Acidithiobacillus ferrooxidans (At. f) and the product of sulfuric acid to dissolve rock phosphate, has been proposed in this paper. The soluble phosphorus could be leached more effectively in the presence of pyrite by At. f than that leached directly by sulfuric acid. The optimal technological parameters are presented. The highest phosphorus leaching rate is 9.00% when the culture substrate is the mixture of FeSO4·7H2O and pyrite, the phosphorus leaching rate is 8.00% when the initial pH and culture time are 2.5 and 5 d, respectively. The optimal rock phosphate particle size is 0.05 mm for the leaching of phosphorus. The bigger the grains of pyrite, the lower the phosphorus leaching rate. The bacterium At. f should be appropriately adaptated, which makes it easier to bioleach soluble phosphorus from rock phosphate.     

Bioleaching of soluble phosphorus from rock phosphate containing pyrite with DES-induced Acidithiobacillus ferrooxidans

The effects of Acidithiobacillus ferrooxidans (At. f) mutated with diethyl sulfate (DES) as a mutagen on the bioleaching of soluble phosphorus (P) from rock phosphate (RP) were investigated. The results show that the oxidative activity of At. f is greatly improved by 1.0% (volume fraction) of DES. Correspondingly, the highest leaching rate of soluble P is also obtained to be 14.9% by the At. f mutated, which is 85.8% higher than that of the adapted At. f without mutation. In addition, the SEM images are significantly performed that the corrosion of RP residue surfaces leached by 1.0% DES-induced At.f is much worse than that of leached by the adapted At. f. All the above indicate that the leaching efficiency of soluble P from RP with pyrite can be greatly improved by using DES-induced At. f to a certain extent.     

风化壳淋积型稀土矿闭矿场铵盐淋出液脱氮研究进展

风化壳淋积型稀土矿是我国重要战略性矿产资源,以铵盐为浸取剂的稀土浸出 工艺导致大量氨氮残留 于闭矿场,易随水体迁移造成氨氮污染,对闭矿场铵盐淋洗液进行脱氮是修复稀土矿 山氨氮污染的有效方法。 综述 了物理化学脱氮方法及其原理,其中吹脱法、膜处理法、湿式氧化法和化学沉淀法适 用于较高浓度氨氮废水的预处 理,离子交换法和折点氯化法适用于较低浓度氨氮废水的处理,可采用不同物理化学 脱氮工艺组合的方法实现稀土 闭矿场淋出废水的脱氮处理,但物理化学方法普遍成本偏高,易造成二次污染。 介绍 了传统生物脱氮工艺,主要包括 三段活性污泥、A / O 与 A² / O、SBR 工艺及生物膜法,传统生物脱氮具有成本低 廉、环境友好等显著优点,但脱氮工艺 流程较复杂、脱氮效率偏低。 论述了短程硝化反硝化、厌氧氨氧化和同步硝化反硝 化等新型生物脱氮技术及其脱氮 原理,相较于传统生物脱氮,采用新型生物脱氮技术可缩短脱氮流程、节省药剂消耗 、提高脱氮效率,在风化壳淋积型 稀土闭矿场铵盐淋出液的脱氮处理上具有较为广阔的应用前景。 采用多种脱氮方法 联合并开发新型工艺是风化壳 淋积型稀土矿闭矿场脱氮的发展趋势。 总结了稀土闭矿场淋出液脱氮的方法及基本 原理,以期为风化壳淋积型稀土 矿闭矿场氨氮的绿色高效脱除提供一定技术指导和理论支撑。     

微生物分解中低品位磷矿的研究实践

综述了解磷微生物的种类及其解磷机理,归纳了近5年来利用解磷微生物分解中低品位磷矿的研究实践,并对解磷微生物在其他矿石中的应用研究进行了简单阐述。     

Bio-decomposition of rock phosphate containing pyrites by Acidithiobacillus ferrooxidans

Leaching soluble phosphorus from rock phosphate containing pyrites by Acidithiobacillusferrooxidans （A. f.） is feasible, and the reaction mechanism is as follows. Pyrites are oxidized by A. f. to produce H2SO4 and FeSO4; the rock phosphate is decomposed by H2SO4, forming soluble phosphorus compounds; and Fe^2＋ from FeSO4 is oxidized to Fe%3＋, providing energy for the growth ofA. f.. In this process, as H2SO4 is produced in the reaction, an acidic condition in the culture medium is formed, which benefits the growth ofA. f. and aids both continuous oxidation of pyrites and leaching of soluble phosphorus from rock phosphate. The fraction of phosphorous leached can reach the largest in the presence of 1.0 g/L Fe^3＋, 200 mg/L Mg^2＋ and 400 mg/L NH^4＋. The optimal technological parameters on the fraction of phosphorous leached are as follows： the volume fraction of inocula ofA. f., the mass ratio of pyrites to rock phosphate and the pH value are in ranges of 5%-25%, 3：1- 5：1 and 1.8- 2.2, respectively.     

用条件平差法求附合导线任一边的方位角中误差

以条件平差原理为基础,推导了求附合导线平差后的任一边方位角的中误差公式,传统的方法中,首先把方位角条件作为第一组条件式进行平差,然后利用第一组改正后的方位角改化二个坐标条件方程式即第二组条件式,最后解出附合导线平差后任一边方位角的权倒数,从而求出附合导线平差后任一边方位角的中误差;计算过程相当烦琐。与传统分组平差相比,本文采用的方法更简单,使学生更容易理解。     

风化壳淋积型稀土矿闭矿场铵盐淋出液化学沉淀脱氮

铵盐浸取风化壳淋积型稀土矿后残留大量铵盐,对稀土矿闭矿场淋出液进行脱氮处理是解决氨氮污染的有效手段。采用化学沉淀法脱除稀土矿闭矿场淋出液中氨氮,研究了沉淀条件对氨氮去除率的影响,利用响应面法优化沉淀工艺参数,通过溶液化学计算、XRD与SEM等分析化学沉淀脱氮过程及机理。结果表明：在pH=7.0、n(N)/n(P)=1.0/1.1、25℃、反应时间240 s的条件下,氨氮去除率可达86.87%;响应曲面拟合结果表明,各因素对氨氮去除率的影响次序为：NaOH的用量(pH)>n(N)/n(P)>反应时间,优化条件下氨氮去除率高达98.02%,化学沉淀后淋出液氨氮浓度<15 mg/L,达到国家排放标准;沉淀产物主要为MgNH₄PO₄·6H₂O及少量MgHPO₄·3H₂O、Mg(OH)₂和Mg₃(PO₄)₂固体,呈表面粗糙的空心棒状结构。     

微波诱变氧化亚铁硫杆菌浸出磷矿粉中可溶性磷

采用微波辐照对氧化亚铁硫杆菌进行诱变,并利用诱变菌在黄铁矿存在条件下从磷矿粉中浸出可溶性磷.结果表明:800 W微波辐照功率条件下(处理4 min),氧化亚铁硫杆菌浸磷的效果较佳,磷的浸出率达12.25%,比原菌提高了52.74%.通过微波诱变可提高氧化亚铁硫杆菌的氧化活性和产酸量,从而增强磷矿粉中可溶性磷的浸出效果.     

高校化工特色生物技术专业实验室建设的探索与实践

根据我国高等学校生物技术专业特点,结合工科化工院校化工学科优势,在构建化工特色生物技术专业实验课程体系;加大实验室建设资金投入,高质量建设化工特色生物技术专业实验室;优化创新生物与化工融合的实验内容,大幅度提高实验教学质量;强化实验室科学管理,促进实验室运转顺畅、有序、高效等方面,进行了化工特色生物技术专业实验室建设的探索与实践,为我国高等学校生物技术专业实验室建设提供参考。