Phosphate rock: origin, importance, environmental impacts, and future roles

2016 ◽  
Vol 24 (4) ◽  
pp. 403-415 ◽  
Author(s):  
Abioye O. Fayiga ◽  
O.C. Nwoke
Keyword(s):  
Contaminated Soils ◽  
Phosphate Rock ◽  
Animal Feed ◽  
Technological Development ◽  
Direct Application ◽  
Environmental Implications ◽  
Hazardous Elements ◽  
Runoff Losses ◽  
Low Solubility

Phosphate rock (PR) is an important mineral resource with numerous uses and applications in agriculture and the environment. PR is used in the manufacture of detergents, animal feed, and phosphate (PO43–) fertilizers. Leaching or runoff losses from PR products like PO43– fertilizers, animal feeds, and detergents could cause eutrophication of surface waters enriched in PO43– by these losses. Although direct application of PR reduces pollution by acting as a slow-release fertilizer, its effectiveness is limited by several factors. The major limitation of PR in direct application is its low solubility, which reduces its availability for soil reactions or plant uptake. Strategies used to increase the effectiveness of directly applied PR are based on increasing acidity, as this increases PR solubility. The application of PR in agriculture may have adverse effects because it contains hazardous elements that could be transferred to the soil through the application of fertilizers, especially after long term use. Chemical analysis of PR obtained from top PR-producing countries, however, shows that hazardous elements contained therein are below tolerable limits for PO43– fertilizers. Studies have also reported that the radionuclides in PR do not pose any radiological risk. The presence of these elements in PR can be put to positive use if they are extracted before they are applied to farmlands. This makes PR a source of rare earth metals and radionuclides that could be used in technological development and as a future energy source. The affinity of PR for metals makes it a useful adsorbent for the removal of metals from aqueous solutions and an excellent material for metal immobilization in contaminated soils. PR is a very important finite resource but its applications have adverse environmental implications.

scholarly journals Carbon nanomaterials in clean and contaminated soils: environmental implications and applications

2014 ◽  
Vol 1 (1) ◽  
pp. 151-199
Author(s):  
M. J. Riding ◽  
F. L. Martin ◽  
K. C. Jones ◽  
K. T. Semple
Keyword(s):  
Organic Contaminants ◽  
Contaminated Soils ◽  
Carbon Nanomaterials ◽  
Environmental Implications ◽  
Long Term Stability ◽  
Surface Areas ◽  
Hydrophobic Nature ◽  
Highly Hydrophobic ◽  
Case Basis

Abstract. The exceptional sorptive ability of carbon nanomaterials (CNMs) for hydrophobic organic contaminants (HOCs) is driven by their characteristically large reactive surface areas and highly hydrophobic nature. Given these properties, it is possible for CNMs to impact on the persistence, mobility and bioavailability of contaminants within soils, either favourably through sorption and sequestration, hence reducing their bioavailability, or unfavourably through increasing contaminant dispersal. This review considers the complex and dynamic nature of both soil and CNM physicochemical properties to determine their fate and behaviour, together with their interaction with contaminants and the soil micro-flora. It is argued that assessment of CNMs within soil should be conducted on a case-by-case basis, and further work to assess the long-term stability of sorbed contaminants and the toxicity of CNMs is required before their sorptive abilities can be applied to remedy environmental issues.

scholarly journals Carbon nanomaterials in clean and contaminated soils: environmental implications and applications

SOIL ◽  
2015 ◽  
Vol 1 (1) ◽  
pp. 1-21 ◽  
Author(s):  
M. J. Riding ◽  
F. L. Martin ◽  
K. C. Jones ◽  
K. T. Semple
Keyword(s):  
Organic Contaminants ◽  
Contaminated Soils ◽  
Carbon Nanomaterials ◽  
Soil Microflora ◽  
Environmental Implications ◽  
Long Term Stability ◽  
Surface Areas ◽  
Hydrophobic Nature ◽  
Highly Hydrophobic

Abstract. The exceptional sorptive ability of carbon nanomaterials (CNMs) for hydrophobic organic contaminants (HOCs) is driven by their characteristically large reactive surface areas and highly hydrophobic nature. Given these properties, it is possible for CNMs to impact on the persistence, mobility and bioavailability of contaminants within soils, either favourably through sorption and sequestration, hence reducing their bioavailability, or unfavourably through increasing contaminant dispersal. This review considers the complex and dynamic nature of both soil and CNM physicochemical properties to determine their fate and behaviour, together with their interaction with contaminants and the soil microflora. It is argued that assessment of CNMs within soil should be conducted on a case-by-case basis and further work to assess the long-term stability and toxicity of sorbed contaminants, as well as the toxicity of CNMs themselves, is required before their sorptive abilities can be applied to remedy environmental issues.

Secular stagnation in the modern world

2018 ◽  
pp. 125-141 ◽  
Author(s):  
S. M. Drobyshevsky ◽  
P. V. Trunin ◽  
A. V. Bozhechkova
Keyword(s):  
Public Debt ◽  
Capital Accumulation ◽  
Technological Development ◽  
Japanese Economy ◽  
Modern World ◽  
Key Factors ◽  
Destruction Process ◽  
Secular Stagnation ◽  
The Impact

The paper studies the factors of secular stagnation. Key factors of long-term slowdown in economic growth include the slowdown of technological development, aging population, human capital accumulation limits, high public debt, creative destruction process violation etc. The authors analyze key theoretical aspects of long-term stagnation and study the impact of these factors on Japanies economy. The authors conclude that most of the factors have significant influence on the Japanese economy for recent decades, but they cannot explain all dynamics. For Russia, on the contrary, we do not see any grounds for considering the decline in the economy since 2013 as an episode of secular stagnation.

Research on the Economic Organization Environmental Impact

2017 ◽  
Vol 68 (3) ◽  
pp. 599-601
Author(s):  
Dan Paul Stefanescu ◽  
Oana Roxana Chivu ◽  
Claudiu Babis ◽  
Augustin Semenescu ◽  
Alina Gligor
Keyword(s):  
Economic Activity ◽  
Economic Organization ◽  
Economic Activities ◽  
Environmental Implications ◽  
Minimal Impact ◽  
Wide Range ◽  
Material Environment ◽  
Negative Effect ◽  
Harmful Effects

Any economic activity carried out by an organization, can generate a wide range of environmental implications. Particularly important, must be considered the activities that have a significant negative effect on the environment, meaning those which pollute. Being known the harmful effects of pollution on the human health, the paper presents two models of utmost importance, one of the material environment-economy interactions balance and the other of the material flows between environmental factors and socio-economic activities. The study of these models enable specific conditions that must be satisfied for the economic processes friendly coexist to the environment for long term, meaning to have a minimal impact in that the residues resulting from the economic activity of the organization to be as less harmful to the environment.

scholarly journals Remediation of mercury-contaminated soils and sediments using biochar: a critical review

Biochar ◽  
2021 ◽  
Author(s):  
Qian Yang ◽  
Yongjie Wang ◽  
Huan Zhong
Keyword(s):  
Health Risks ◽  
Contaminated Soils ◽  
Functional Materials ◽  
Redox Conditions ◽  
Existing Problems ◽  
Soils And Sediments ◽  
Underlying Mechanisms ◽  
Biochar Amendment

AbstractThe transformation of mercury (Hg) into the more toxic and bioaccumulative form methylmercury (MeHg) in soils and sediments can lead to the biomagnification of MeHg through the food chain, which poses ecological and health risks. In the last decade, biochar application, an in situ remediation technique, has been shown to be effective in mitigating the risks from Hg in soils and sediments. However, uncertainties associated with biochar use and its underlying mechanisms remain. Here, we summarize recent studies on the effects and advantages of biochar amendment related to Hg biogeochemistry and its bioavailability in soils and sediments and systematically analyze the progress made in understanding the underlying mechanisms responsible for reductions in Hg bioaccumulation. The existing literature indicates (1) that biochar application decreases the mobility of inorganic Hg in soils and sediments and (2) that biochar can reduce the bioavailability of MeHg and its accumulation in crops but has a complex effect on net MeHg production. In this review, two main mechanisms, a direct mechanism (e.g., Hg-biochar binding) and an indirect mechanism (e.g., biochar-impacted sulfur cycling and thus Hg-soil binding), that explain the reduction in Hg bioavailability by biochar amendment based on the interactions among biochar, soil and Hg under redox conditions are highlighted. Furthermore, the existing problems with the use of biochar to treat Hg-contaminated soils and sediments, such as the appropriate dose and the long-term effectiveness of biochar, are discussed. Further research involving laboratory tests and field applications is necessary to obtain a mechanistic understanding of the role of biochar in reducing Hg bioavailability in diverse soil types under varying redox conditions and to develop completely green and sustainable biochar-based functional materials for mitigating Hg-related health risks.

scholarly journals Direct application of reactive phosphate rock on improving maize yield in tidal swampland

2021 ◽  
Vol 648 (1) ◽  
pp. 012175
Author(s):  
A F Siregar ◽  
Husnain ◽  
I W Suastika ◽  
N P S Ratmini ◽  
I A Sipahutar ◽  
...  
Keyword(s):  
Phosphate Rock ◽  
Maize Yield ◽  
Direct Application ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock

PROSPECTS FOR THE DEVELOPMENT OF THE INNOVATIVE MARKET OF CHEMICAL TECHNOLOGIES IN RUSSIA

2021 ◽  
Author(s):  
Natalia Nikolaeva ◽  
Nikita Grinev ◽  
Pavel Barabanov ◽  
Elena Kulyuasova ◽  
Nikolay Kulyuasov
Keyword(s):  
Russian Federation ◽  
Chemical Industry ◽  
Technological Development ◽  
Global Market ◽  
The State ◽  
Economic Relations ◽  
Industrial Enterprises ◽  
Chemical Complex ◽  
The Russian Federation

"The transition of Russia to sustainable economic growth is impossible without stimulating the use of the achievements of science and education, high technologies, promoting innovative activity as an essential premise for the development of social production and subjects of economic relations. For the state, the promotion of innovation is a priority in the economic policy sector, since it is the level of scientific and technological development that largely determines the long-term strategic advantages of the country, and the prospects for the development of the state largely dependent on the level of innovation development. For a long time, the Ministry of Economic Development of the Russian Federation has been implementing the Strategy for Innovative Development of the Russian Federation. It includes 20 key steps and is developed based on the provisions of the concept of long-term development of the Russian Federation. The main results should have been, firstly, an increase in spending on science and innovation, and secondly, an increase in the share of industrial enterprises that introduce innovations in production. It was assumed that their share will increase by 4-5 times by 2020, compared with 2010 year. Not everything has been achieved, and there is a lot to strive for. This study is devoted to the driver of scientific and technological progress - the chemical complex of Russia. The chemical complex plays a significant role in the implementation of the most important socio-economic programs of the country. The study is devoted to the consideration of the most important prospects and key alternatives for the development of the chemical industry related to different areas of innovation. Conclusions will be made on key technologies and products that can change the position of the chemical industry in the global market."

Sign in / Sign up

Export Citation Format

Share Document