Slurry electrolysis of ocean polymetallic nodule

The ocean poly-metallic nodule was leached by using slurry electrolysis process in HCl-NaCl medium.The leaching rates of Mn,Co,Cu and Ni in the ocean poly-metallic nodule are all above 97%.Meanwhile,the high purity of electrolytic MnO2 is also obtained as an anode product.The effects of electrolysis electric quantity,acidity,temperature,slurry density,grain size and iron ions concentration were studied.The results show that the ocean poly-metallic nodule can be treated economically in the slurry electrolysis process.

Detrital and authigenic(?) baddeleyite(ZrO_2) in ferromanganese nodules of Central Indian Ocean Basin

Occurrence of baddeleyite（ZrO_2） which is a rare mineral has been recorded in ferromanganese nodules of Central Indian Ocean Basin（CIOB）.The mineral occurs either as independent isolated sub-rounded to elliptical grains or in clusters forming fine subhedral crystals（〈3μm） within ferromanganese concretionary growth bands.The mode of occurrence,texturai features and chemistry of the mineral suggest detrital and possibly an authigenic origin for baddeleyite.For authigenic origin it is proposed that zirconium might have got released either from the terrigenous sediments or the altered seafloor rocks forming halogen complexes and subsequently it has re-precipitated in me form of baddeleyite within manganese nodules under oxic to sub-oxic conditions.

Implications of REE incorporation and host sediment influence on the origin and growth processes of ferromanganese nodules from Central Indian Ocean Basin

This study presents new major,trace and REE data for thirty-five ferromanganese nodules recovered from areas representing three different sediment types(siliceous,red clay and their transition zone)in the Central Indian Ocean Basin(CIOB)to address their genetic aspects,classification,growth rate,nature of host sediments and influence of REE in the processes of nodule formation.The nodules from CIOB are mostly either hydrogenetic(metals coming from oxygenated bottom water)and diagenetic(metals coming from suboxic sediment pore water)or a combination of both,depending on the source of supply of metal.However,a number of biogeochemical processes mediate this supply of metals which again changes from time to time,making the nodule growth process highly dynamic.This study suggests that at the initial stage of nodule growth,host sediments do not play much role in controlling the growth processes for which REEs can enter both Mn and Fe oxyhydroxide phases equally.Thus,the bottom water signature is imprinted in these early formed nodules irrespective of their host sediment substrate but with gradual growth and burial in the sediment,the main mode of metal enrichment becomes diagenetic through sediment pore water.This tends to increase the concentration of Mn,Ni and Cu over other elements which are retained in the sediment fraction.Among the REEs,Ce concentration of the nodules shows significant positive anomaly due to variation in redox potential and hence its magnitude can be used to get an idea about the metal enrichment procedure and the genetic type of the nodules.However,based on host sediment only,not much difference is found in the magnitude of Ce anomaly in these nodules.On the other hand,discrimination diagram,based on HFSE and REY chemistry,indicates that most of these nodules are of diagenetic origin under oxic condition with a trend towards hydrogenetic field.Further,the genetic type of the ferromanganese nodules from the CIOB are more effectively differentiated by a combination of their major and trace element concentrations rather than solely based on their REE or HFSE chemistry or host sediment substrate.

Mechanism and Modes of Microbial Minerogenesis of Polymetallic Nodules on the Ocean Floor

: This paper presents a quantitative analysis of the relations of the occurrence of polymetallic nodules with the geochemical actions of microbes in the seawater, pore water and sediments at the bottom of the eastern Pacific Ocean basin. Emphasis is laid on the relations of the activity intensity and biochemical transformation rate of aerobic bacteria (iron bacteria, Thiobacillus thioparus, halobacteria and manganese—oxidizing bacteria) and anaerobic bacteria (sulphate—reducing bacteria, denitrifying bacteria, Thiobacillus denitrificans) with mineralization. The experimental research on the migration and accumulation of ore-forming elements caused by microbial and chemical actions shows that the microbes have changed the conditions of oxidation and reduction in the system, and their effect on the element precipitation is much stronger than the chemical actions and accelerates the enrichment of Fe and Ma It demonstrates that the microbes can change the environment to promote the accumulation of ore-forming elements, thus leading to indirect mineralization.

Kinetics of oxidative leaching of ocean polymetallic nodules in molten potassium hydroxide medium

The kinetics of oxidative leaching of ocean polymetallic nodules in molten potassium hydroxide medium was investigated in terms of the gas-flow rate, stirring rate, reaction time, reaction temperature and partial pressure of oxygen on the ratio of manganese conversion in ocean polymetallic nodules. The category of the rate controlling step was determined. The process of the liquid-phase oxidation reaction can be described by surface chemical reaction-controlled non-reaction shrinking core model(SCM), the apparent activation energy was achieved and the rate equation was put forward. From the equation, it can be concluded that the reaction rate mainly depends on the reaction temperature and the partial pressure of oxygen.

Abundance of total bacteria, ATP and manganese-oxidating bacteria in the sediments and manganese nodules of the Northwestern Pacific Ocean

In the seawater and sediments of the ocean, there exist huge quantities of bacteria whose living activities cause various chemical reaction processes. It is demonstrated that microorganisms play a fundamental role on chemical changes of the sediments and diageneses. Over the last twenty years, great interest has been increased about the role of deep-sea bacteria in the ferromanganese sedimentary process. Much work has been done on this aspect in the Atlantic Ocean, the Baltic Sea and the Pacific O-

西太平洋M2海盆区巨型底栖动物分布及其与结核赋存条件的关系研究

深海平原和海盆是地球上最大的生态系统,其部分区域海底沉积物上赋存有大量的多金属结核,结核不仅增加了海底栖息地复杂性和空间异质性,也为附着生物提供硬质基底,形成了特殊的深海底栖生态系统。本研究利用深海摄像技术获取的高清海底图像,分析了西太平洋北京先驱多金属结核合同区M2-B1区块巨型底栖动物生物多样性、群落结构及其对结核大小和覆盖率的响应。结果发现了9门25个类群巨型底栖动物,包括多孔动物门、棘皮动物门、节肢动物门、刺胞动物门、脊索动物门、环节动物门、苔藓动物门、软体动物门、原生动物门等,平均密度为0.19 ind./m^(2)。西太平洋巨型底栖动物主要类群与东太平洋克拉里昂-克利珀顿区(CC区)基本一致,平均密度略低于CC区。多金属结核的覆盖率和结核粒径大小是该区动物类群密度的主要环境驱动因素,巨型底栖动物密度整体与多金属结核覆盖率呈正相关关系,与结核粒径呈负相关关系;而不同动物门类密度与结核覆盖率和粒径的关系存在多种模式,多孔动物和棘皮动物密度随结核覆盖率增加而增加,刺胞动物和软体动物在结核覆盖率大于64%后随结核覆盖率增加而增加,棘皮动物和刺胞动物密度在粒径大于3.15 cm后保持稳定不变。本研究结果初步揭示了该区域巨型底栖动物分布格局及其驱动因素,将可为未来深海采矿环境影响评估提供重要的科学支撑。

Geochemical characteristics of sediments from the COMRA registered pioneer area (CRPA),equatorial northeastern Pacific Ocean

COMRA(China Ocean Mineral Resources Association) registered pioneer area (CRPA) is located in the western part of the area between the Clarion and Clipperton Fraction Zones (CCFZs). Based on distinctive color and bio-disturbing properties, two layers are recognized in the sediment columns from the CRPA: a pale brown layer (Unit A) on the top and a dark for layer (Unit B) in the lower part. Color division between them can be explained as a hiatus. As a resu1t, the two units are different to each other in chemical composition and sediment properties. It is found that contents of P2O5, MnO2, CaO, Na2O in sediments of older Unit B are higher, but SiO2 content is slightly lower. Based on correlation analysis, Mn and Fe in the sediments have different origins. The former is mainly precipitated in authigenic process, whilst the latter is closely related to terrigenous detritus. Therefore, the differences in chemical composition of the sediments are caused by different sedimentation settings.

海底多金属结核水力式集矿系统产生的污泥浓度分析

研究了海底多金属结核水力式集矿系统在不同工况条件下产生的污泥浓度。结果表明,海底多金属结核水力式集矿系统中输送系统脱泥排放产生的污泥浓度远高于捕捉系统扰动底质淤泥产生的污泥浓度,是产生水体浑浊的主要原因之一。试验过程中污泥浓度变化曲线呈现先迅速上升后快速下降的变化趋势,随着捕捉系统水泵油压增大,污泥浓度增大;输送系统水泵油压对污泥浓度影响不明显。

基于高斯混合模型的太平洋深海盆地多金属结核成因分类

多金属结核类型成因分类是海底矿产资源关注的重要地质问题,诸多学者一直探索利用多金属结核地球化学特征进行多金属结核成因判别。近年来,随着大数据分析方法的应用,为探索利用机器学习技术进行多金属结核地球化学特征进行成因分类提供了很好的思路和方法。本文基于多年调查研究获取的太平洋多金属结核地球化学数据,利用高斯混合模型聚类分析技术,实现了太平洋深海盆地多金属结核成因分类,并对水成型结核进行了进一步判别分析,共划分出成岩型、混合型、水成Ⅰ型和水成Ⅱ型四类成因多金属结核,为太平洋深海找矿突破和资源评价提供重要依据。同时,不同成因类型结核空间预测结果显示,西北太平洋海域是水成Ⅰ型富钴多金属结核的主要分布区域之一,主要分布在马尔库斯—威克海山群、麦哲伦海山群北部、马绍尔海山群和中太平洋海山群西南部的山间盆地,以及附近的皮嘉费他海盆和中太平洋海盆西北部,是未来西太平洋富钴多金属结核资源找矿突破需要关注的关键海域。

两相淋滤实验在深海铁锰结核研究中的应用

两相淋滤实验能够分离深海铁锰结核的水生矿物相和残留矿物相组分,为研究深海铁锰结核成矿作用以及古海洋环境提供直接信息。为了探讨两相淋滤实验在不同成因类型铁锰结核成矿作用研究中与全岩样品分析结果的差异,本文选取了西太平洋海山区和东太平洋CC区6个站位的铁锰结核样品进行了全岩样品矿物学和元素地球化学分析,利用两相淋滤实验分别提取了铁锰结核样品的水生矿物相和残留矿物相组分,并进行了元素地球化学分析。结果表明,不同类型铁锰结核的两相淋滤实验中残留相质量占比为14.0%~17.6%,变化较小,残留矿物相组分中Nb、Rb、Ta、Ti、Zr等元素含量较高。水生矿物相组分中的Co、Ni、Cu、Zn、Sr、REY元素含量及其比值变化与全岩样品基本一致。水生矿物相与残留矿物相中Ti、Nb、Sr含量的比值与全岩样品的Mn Fe值呈较好的负相关关系,可作为研究铁锰结核成矿环境的指标参数。

Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

中国多金属结核开辟区沉积物地球化学特征

对中国多金属结核开辟区沉积物的详细研究表明 ,研究区内沉积物处于氧化至弱氧化环境 ,两种色调的沉积物在粒度分布特征以及化学组成上都存在着显著的差异 ,它们是不同沉积环境的反应 .不同色调之间的界面为一沉积间断面 .沉积物中的铁和锰具有不同的来源 ,铁可能以岩源碎屑为主 ,而锰则更可能是自生成因 .钙和镁以生物成因为主 .

大洋多金属结核开采研究进展与现状

大洋多金属结核研究分为 4个阶段 :科学探索、大规模研究、技术储备和商业开采。介绍了OMI、OMA和OMCO等国际财团对大洋多金属结核进行的试采活动 ,以及国外对深海采矿系统关键部件或子系统如结核集矿机、扬矿子系统等的研究开发情况。

太平洋多金属结核中铁锰矿物分析及成因研究

铁锰矿物是大详多金属结核的重要组成，了解不同类型结核中主要铁锰矿物种类、形态、分布特点和结晶程度等，不仅有助于对锰矿物乃至多金属结核成因的研究，而且对选矿冶炼和资源的综合利用也具有现实意义．本文通过透射电子显微镜等多种手段综合分析与鉴定，指出多金属结核中主要铁锰矿物有钙锰矿、水羟锰矿、水钠锰矿、方锰矿、锰铁矿和针铁矿等．结晶程度普遍较差，钙锰矿结晶相对好于其他矿物，并在粗糙型结核中含量高，外层至核心含量稳定，变化小．水羟锰矿广为分布，但结晶差．铁矿物含量东区低于西区，结核外壳铁含量高于内核．锰矿物分布在叠层石柱体和纹层内，呈束状、纤维状和树枝状，与建造多金属结核的超微生物菌丝体形态一致．粗糙型结核是选冶的主要对象．

大洋采矿输送软管动力特性的数值研究

在大量勘探数据的基础上 ,对中国东太平洋 7.5万 km2矿区采矿环境进行研究 ,得出集矿机是否安全行驶 ,直接关系着大洋采矿的成败。影响集矿机行驶的因素很多 ,其中输送软管是重要因素之一。通过理论分析计算和小型模拟实验相结合的研究方法 ,进行了软管与集矿机受力分析与仿真计算研究 ,开发了相应的应用软件。总结了大洋采矿系统中输送软管动态特性数值研究的最新研究成果 ,对我国大洋多金属结核矿产资源的开发 。

中太平洋海山多金属结壳的成矿特征

根据我国大洋多金属结壳的调查资料并结合其他相关的研究结果 ,对中太平洋海山区多金属结壳的类型、产状、成分、结构、分布等成矿特征进行了初步的研究 .结果表明 ,中太平洋海山区富钴结壳广泛发育 ,但成矿特征较大地受地形、水深、基岩类型等成矿环境因素的影响与制约 .

大洋多金属结核熔炼合金锈蚀工艺的研究

研究了大洋多金属结核熔炼合金锈蚀浸出分离除铁工艺。采用能明显加快锈蚀反应速度的高效添加剂，在最佳工艺条件下，于浓度为４５ｇ／Ｌ．的稀盐酸介质中，鼓空气锈蚀－０．１８０ｍｍ合金粉末７ｈ，反应完全，有价金属Ｃｕ，Ｃｏ，Ｎｉ浸出率分别达９８．３３％，９７．８６％，９９．４６％，锈蚀液中铁为痕量，实现一步彻底分离。

镍生产工艺研究进展

介绍了降低生产成本、提高镍来源的镍生产新工艺的原理和概况,包括生物浸出、海洋多金属结核的利用、选择性还原法以及从废弃原料中回收金属等,分析了各种方法的机理及特点。

新型还原剂与海洋锰结核还原浸出的研究

采用一种还原剂BR与锰结核发生反应 ,再用硫酸浸取有价金属离子。研究了锰结核与还原剂之配料比、还原剂的细度对还原效果的影响 ,考察了还原过程中温度和物相的变化 ;并探讨出合适的浸出液pH值 ,浸取温度 ,浸取时间等浸取条件。结果表明锰结核与还原剂配料比为 4∶1,还原剂的细度为 -0 .12 5mm ,浸出液pH值为 2 .2 ,无外热浸出 3 5min ,锰、铜、钴、镍的浸出率分别达到 98.2 0 %、99.88%、99.91%、99.95 %、铁的浸出率为 18.2 3 %。