scholarly journals A Low Cost of Burning Raw Material For PO43−-P And F− Solidification/Stabilization In Phosphogypsum

2021 ◽  
Author(s):  
Li Bing ◽  
Shu Jiancheng ◽  
Chen Mengjun ◽  
Zeng Xiangfei ◽  
Liu Renlong
Keyword(s):  
Economic Evaluation ◽  
Low Cost ◽  
Weight Ratio ◽  
Treatment Method ◽  
Raw Material ◽  
Soluble Phosphate ◽  
Leaching Test ◽  
Liquid Ratio ◽  
The Sustainable Development ◽  
Leaching Solution

Abstract Phosphogypsum (PG) contains a lot of soluble phosphate (PO4 3−-P) and fluorine ion (F−), which seriously has hindered the sustainable development of phosphorous chemical industry. In this study, a new burning raw material (BRM) was used for the stabilize of PO43−-P and F− in PG. The characteristics of PG and BRM, stabilize mechanism of PO43−-P and F−, leaching test and economic evaluation were investigated. The effect of PG and BRM weight ratio, solid to liquid ratio, reaction time and reaction temperature on the concentrations of PO43−-P and F− were studied. The results showed that the concentration of F− in PG leaching solution was 8.65 mg/L and the removal efficiency of PO43−-P was 99.78 %, as well as the pH of PG leaching solution was 8.12, when the weight ratio of PG and BRM was 100:2, and the solid to liquid ratio was 4:1, reacting for 24 h at the temperature of 30 ℃. PO43−-P and F− were mostly solidified as Ca5(PO4)3F, CaPO3(OH), Ca5(PO4)3(OH), Ca2P2O7·2H2O, CaSO4PO3(OH)·4H2O, CaF2, and CaFPO3·2H2O. Leaching test results indicated that the concentrations of PO4 3−-P, F− and heavy metals were less than the integrated wastewater discharge standard (GB8978-1996). Economic evaluation revealed that the cost of PG treatment was $ 0.88/ton. This study provides a new low cost and harmless treatment method for PG.

Under High Pressure: Spherical Glass Flotation and Instrument Housings in Deep Ocean Research

2009 ◽  
Vol 43 (5) ◽  
pp. 105-109 ◽  
Author(s):  
Steffen Pausch ◽  
Detlef Below ◽  
Kevin Hardy
Keyword(s):  
High Pressure ◽  
Low Cost ◽  
Weight Ratio ◽  
Deep Ocean ◽  
The Other ◽  
Raw Material ◽  
Advanced Manufacturing Technology ◽  
Advanced Manufacturing ◽  
High Quality ◽  
Glass Spheres

AbstractAll stationary and autonomous instrumentation for observational activities in ocean research have two things in common, they need pressure-resistant housings and buoyancy to bring instruments safely back to the surface. The use of glass spheres is attractive in many ways. Glass qualities such as the immense strength‐weight ratio, corrosion resistance, and low cost make glass spheres ideal for both flotation and instrument housings. On the other hand, glass is brittle and hence subject to damage from impact. The production of glass spheres therefore requires high-quality raw material, advanced manufacturing technology and expertise in processing. VITROVEX® spheres made of DURAN® borosilicate glass 3.3 are the only commercially available 17-inch glass spheres with operational ratings to full ocean trench depth. They provide a low-cost option for specialized flotation and instrument housings.

scholarly journals Ultrasonic enhanced water washing method for extracting sodium fluoride from spent pot lining

2021 ◽  
Vol 2079 (1) ◽  
pp. 012004
Author(s):  
Yongrong Qi ◽  
Yuan Gong ◽  
Haibin Wang ◽  
Li Peng ◽  
Liting Fan ◽  
...  
Keyword(s):  
Low Cost ◽  
Ultrasonic Waves ◽  
Raw Material ◽  
Process Conditions ◽  
Ultrasonic Power ◽  
Water Washing ◽  
Washing Process ◽  
Leaching Solution ◽  
Washing Method ◽  
Leaching Efficiency

Abstract A large amount of spent pot lining (SPL) is produced by cryolite-alumina melting electrolysis process, and the fluoride content in the leaching solution is up to 6000 mg/L, which belongs to hazardous waste. If SPL is not handled effectively, it will cause great harm to the environment. Because the NaF rich in SPL is an important raw material for the synthesis of cryolite by carbonation, this paper uses SPL as the raw material to extract NaF. On the basis of exploring the process conditions of water washing leaching NaF, ultrasonic wave was introduced to enhance mass transfer and the effects of ultrasonic cavitation on water washing process was compared. The results show that ultrasonic waves can effectively shorten the time for water washing to reach equilibrium and further improve the efficiency of NaF leaching. Under the optimal process conditions determined by the experiment, when the ultrasonic power is 400 W, the time for washing to reach equilibrium is shortened from 50 min to 40 min, and the NaF leaching efficiency is increased from 67.25 % to 70.42 %. While improving the leaching efficiency, the water consumption is effectively reduced, and the purity of the recovered product NaF is 96.82 %. This research provides a technical reference for the harmless and low cost leaching of NaF from SPL in the aluminium electrolysis industry.

scholarly journals End-of-Life Alternatives of Glass Reinforced Polyester Boat Hulls Compared by LCA

2018 ◽  
Vol 27 (4) ◽  
pp. 096369351802700 ◽  
Author(s):  
Mehmet Önal ◽  
Gökdeniz Neşer
Keyword(s):  
End Of Life ◽  
Environmental Impacts ◽  
Raw Materials ◽  
Weight Ratio ◽  
Cost Effective ◽  
Raw Material ◽  
Photochemical Oxidation ◽  
Human Toxicity ◽  
Vacuum Infusion ◽  
Infusion Method

Glass reinforced polyester (GRP), as a thermoset polymer composites, dominates boat building industry with its several advantages such as high strength/weight ratio, cohesiveness, good resistance to environment. However, proper recovering and recycling of GRP boats is became a current environmental requirement that should be met by the related industry. In this study, to propose in a cost effective and environmentally friendly way, Life Cycle Assessment (LCA) has been carried out for six scenarios include two moulding methods (namely Hand Lay-up Method, HLM and Vacuum Infusion Method, VIM) and three End-of-Life (EoL) alternatives(namely Extruding, Incineration and Landfill) for a recreational boat's GRP hulls. A case study from raw materials purchasing phase to disposal/recycling stages has been established taking 11 m length GRP boat hull as the functional unit. Analysis show that in the production phase, the impacts are mainly due to the use of energy (electricity), transport and raw material manufacture. Largest differences between the methods considered (HLM and VIM) can be observed in the factors of marine aquatic ecotoxicity and eutrophication while the closest ones are abiotic depletion, ozon layer depletion and photochemical oxidation. The environmental impact of VIM is much higher than HLM due to its higher energy consumption while vacuum infusion method has lower risk than hand lay-up method in terms of occupational health by using less raw material (resin) in a closed mold. In the comparison of the three EoL techniques, the mechanical way of recycling (granule extruding) shows better environmental impacts except terrestrial ecotoxicity, photochemical oxidation and acidification. Among the EoL alternatives, landfill has the highest environmental impacts except ‘global warming potential’ and ‘human toxicity’ which are the highest in extrusion. The main cause of the impacts of landfill is the transportation needs between the EoL boats and the licenced landfill site. Although it has the higher impact on human toxicity, incineration is the second cleaner alternative of EoL techniques considered in this study. In fact that the similar trend has been observed both in production and EoL phases of the boat. It is obvious that using much more renewable energy mix and greener transportation alternative can reduce the overall impact of the all phases considerably.

scholarly journals Effects of Urbanization on Ecosystem Services in the Shandong Peninsula Urban Agglomeration, in China: The Case of Weifang City

Urban Science ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 54
Author(s):  
Yuejuan Yang ◽  
Hao Zhang ◽  
Xinquan Zhao ◽  
Zhizhang Chen ◽  
Aiguo Wang ◽  
...  
Keyword(s):  
Sustainable Development ◽  
Ecosystem Services ◽  
Remote Sensing Data ◽  
Population Data ◽  
Raw Material ◽  
Nutrient Cycle ◽  
The Sustainable Development ◽  
Impact Of Urbanization ◽  
Academy Of Sciences ◽  
The Impact

Ecosystem services are the material basis of economic and social development, and play essential roles in the sustainable development of ecosystems. Urbanization can remarkably alter the provision of ecosystem services. Most studies in this area have focused on densely populated metropolises with poor ecological environments, while comparatively few studies have focused on cities with low ecological pressures. Therefore, to avoid continuing to engage in the repetitive pattern of destroying first and rehabilitating later, quantitative analyses of urbanization and ecosystem services should be carried out in representative cities. In this study, based on partial least squares-discriminant analysis, kernel density estimation, and correlation analysis, we quantitatively evaluated the impact of urbanization on ecosystem services in Weifang city. The Data Center for Resources and Environmental Sciences at the Chinese Academy of Sciences and the Institute of Geographic Sciences and Natural Resources Research provided remote sensing data on land use, the gross domestic production (GDP), population data, and ecosystem services. The results were as follows: (1) The variation in population, GDP, and built-up areas consistently increased throughout the study period, whereas the ecosystem service values (ESVs) decreased; (2) food production, raw material production, nutrient cycle maintenance, and soil conservation were decisive ecosystem services that led to vast reductions in ESVs during the process of urbanization; and (3) the negative correlation coefficient between built-up areas and ecosystem services was greater than that between the population or GDP and ecosystem services, which indicated that the impacts of population and economic urbanization on ecosystem services lagged behind the impact of land urbanization. This study provides references for fully recognizing the ecological effects of urbanization, and make suggestions regarding the application of ecosystem services in sustainable development.

scholarly journals The Productive Landscape in the Desert Margin for the Sustainable Development of Rural Settlements: An Innovative Greenbelt for Maranjab Desert in Iran

2021 ◽  
Vol 13 (4) ◽  
pp. 2077
Author(s):  
Mahnaz Sarlak ◽  
Laura Valeria Ferretti ◽  
Rita Biasi
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Low Cost ◽  
Agricultural Systems ◽  
Rural Settlements ◽  
Green Belt ◽  
The Sustainable Development ◽  
Research Questions ◽  
New Form ◽  
Low Levels

About two billion rural individuals depend on agricultural systems associated with a high amount of risk and low levels of yield in the drylands of Asia, Africa, and Latin America. Human activities, climate change and natural extreme events are the most important drivers of desertification. This phenomenon has occurred in many regions of Iran, particularly in the villages in the periphery of the central desert of Iran, and has made living in the oases so difficult that the number of abandoned villages is increasing every year. Land abandonment and land-use change increase the risk of desertification. This study aims to respond to the research questions: (i) does the planning of green infrastructures on the desert margin affect the distribution and balance of the population? (ii) how should the green belt be designed to have the greatest impact on counteracting desertification?, and (iii) does the design of productive landscape provide the solution? Through a wide-ranging and comprehensive approach, this study develops different scenarios for designing a new form of green belt in order to sustainably manage the issues of environmental protection, agricultural tradition preservation and desertification counteraction. This study proposes a new-traditional greenbelt including small low-cost and low-tech projects adapted to rural scale.

Characterization and A Preliminary Study of TiO2 Synthesis from Lampung Iron Sand

2020 ◽  
Vol 849 ◽  
pp. 113-118
Author(s):  
Yayat Iman Supriyatna ◽  
Slamet Sumardi ◽  
Widi Astuti ◽  
Athessia N. Nainggolan ◽  
Ajeng W. Ismail ◽  
...  
Keyword(s):  
Food Packaging ◽  
Xrd Analysis ◽  
Major Elements ◽  
Raw Material ◽  
Solid Residue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Leaching Solution ◽  
Ti Content

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.

scholarly journals Removal of Cadmium(II) from Water using Modified Citrus limettioides Peels: Thermodynamic and Isotherm Studies

2019 ◽  
Vol 32 (1) ◽  
pp. 73-78
Author(s):  
P. Janaki ◽  
R. Sudha ◽  
T.S. Sribharathi ◽  
P. Anitha ◽  
K. Poornima ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Low Cost ◽  
Raw Material ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Adsorption Method ◽  
Chemically Modified ◽  
Adsorption Performance ◽  
Monolayer Adsorption ◽  
Isotherm Equations

The adsorption performance of sulphuric acid treated low cost adsorbent synthesized by using Citrus limettioides peel as an effective raw material for the removal of cadmium(II) from water. The batch adsorption method was carried out to optimize some parameters like contact time, pH and adsorbent dose. The nonlinear isotherm equations were used to calculate the different isotherm constant of five isotherm models namely Freundlich, Langmuir, Dubinin-Radushkevich, Redlich-Peterson and Sips. The Langmuir monolayer adsorption capacity of chemically modified Citrus limettioides peel was found to be 287.60 mg g-1. The negative values of ΔGº and ΔHº showed that the adsorption process is spontaneous and exothermic.

Feasibility of cereal straw for industrial utilization in Minnesota

2000 ◽  
Vol 15 (1) ◽  
pp. 2-8 ◽  
Author(s):  
N.C. Wagner ◽  
S. Ramaswamy ◽  
U. Tschirner
Keyword(s):  
Animal Feed ◽  
Raw Materials ◽  
Low Cost ◽  
Economic Feasibility ◽  
Raw Material ◽  
Cereal Straw ◽  
Industrial Utilization ◽  
Industrial Use ◽  
On Farm ◽  
And Storage

AbstractA pre-economic feasibility study was undertaken to determine the potential of cereal straw for industrial utilization in Minnesota. Specifically, utilizing straw for pulp and paper manufacture was of interest. The availability of cereal straw fiber supplies at various locations across the state of Minnesota, along with pre-processing issues such as transportation, harvesting, handling, and storage, are discussed and priced. The greatest economic advantage of straw for industrial use appears to be the low cost of the raw material compared to traditional raw materials. This also provides an excellent opportunity for additional income for farmers. The methodology and information provided here should be helpful in evaluating the feasibility of utilizing straw for other industrial purposes in other parts of the world. However, in some Third World countries, long-standing on-farm, traditional uses of cereal straws for fuel, fiber, and animal feed may limit their availability for industrial utilization.

Advances in absorbents and techniques used in wet and dry FGD: a critical review

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lokesh Kumar ◽  
Susanta Kumar Jana
Keyword(s):  
Power Plants ◽  
Low Cost ◽  
Fine Particulate Matter ◽  
Packed Column ◽  
Toxic Substance ◽  
Cost Effective ◽  
Solid Wastes ◽  
Raw Material ◽  
Process Industries ◽  
Slurry Bubble Columns

Abstract Sulfur dioxide is considered as an extremely harmful and toxic substance among the air pollutants emitted from the lignite- and other high-sulfur-coal based power plants, old tires processing units, smelters, and many other process industries. Various types of absorbents and desulfurization technologies have been developed and adopted by the industries to reduce the emission rate of SO2 gas. The present paper focuses on the ongoing advances in the development of varieties of regenerative and non-regenerative absorbents viz., Ca-based, Mg-based, Fe-based, Na-based, N2-based, and others along with various FGD technology, viz., wet, dry or semi-dry processes. Additionally, different types of contactors viz., packed column, jet column, spray tower, and slurry bubble columns along with their significant operational and design features have also been discussed. In the existing or newly installed limestone-based FGD plants, an increasing trend of the utilization of newly developed technologies such as limestone forced oxidation (LSFO) and magnesium-enhanced lime (MEL) are being used at an increasing rate. However, the development of low-cost sorbents, particularly suitable solid wastes, for the abatement of SO2 emission needs to be explored sincerely. Many such wastes cause air pollution by way of entrainment of fine particulate matter (PM), groundwater contamination by its leaching, or brings damage to crops due to its spreading onto the cultivation land. One such pollutant is marble waste and in this work, this has been suggested as a suitable substitute to limestone and cost-effective sorbent for the desulfurization of flue gases. The product of this process being sellable in the market or may be used as a raw material in several industries, it can also prove to be an important route of recycling and reuse of one of the air and water-polluting solid wastes.

Removal of Phosphate Species from Solution by Adsorption onto Red and Grey Ceramic Clay Used as Adsorbent

2014 ◽  
Vol 675-677 ◽  
pp. 434-439
Author(s):  
Yi Liang Yao ◽  
Chang Yu Lu ◽  
Wie Sheng Guan ◽  
Hai Gang Gou ◽  
Wei Huang
Keyword(s):  
Waste Water ◽  
Low Cost ◽  
Phosphate Removal ◽  
Liquid Ratio ◽  
Phosphate Species ◽  
Water Problems ◽  
And Control ◽  
Water Eutrophication ◽  
Clay Materials ◽  
Ceramic Clay

Waste water is becoming more and more around us and phosphates exit everywhere in waste water. Eutrophication, the most common phenomenon caused by phosphate, can lead to water problems. Therefore, searching suitable materials to remove and control phosphate in waste water is of great significance. In this reach project, the method of adsorption was chosen to remove phosphate and two kinds of ceramic clay materials which were low cost and easily available as adsorbent for adsorption were used for phosphate removal. According to the removal efficiency of phosphate removal, temperature, solid to liquid ratio, the original concentration of phosphate and experiment time were studied in the experiments.

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