Dosage Of Sodium Silicate Research Articles

Shear Strength Characteristics of Coastal Soil Treated with Sodium Silicate

In recent times, rapid developments near coastal areas are gaining attraction and attention from industry players. This necessitates further understanding of soil behavior found in these areas. Soil stabilization can further enhance the physical and engineering characteristics of soils used for development purposes. For this study, a series of laboratory tests were conducted to determine the potential of Sodium Silicate (TX-85), a liquid-type chemical soil stabilizer, to improve the properties of coastal soil obtained in Kota Kinabalu, Sabah. The soil samples were subjected to a series of laboratory tests, which includes the pH and Unconfined Compression Strength (UCS). The dosages of Sodium Silicate mixed with the soil were 4, 5, and 7% by soil sample weight, with curing intervals of 3 hours, 24 hours and 48 hours, respectively. The optimal dosage of Sodium Silicate observed in this study is 4%, at 48 hours curing period. This combination of stabilizer dosage and curing period produced the highest strength increment, where the UCS value increased by 90.3%, from 262.1 kPa to 498.8 kPa.

Study on the long-term performance of cement-sodium silicate grout and its impact on segment lining structure in synchronous backfill grouting of shield tunnels

Synchronous backfill grouting is an important procedure in the construction of shield tunneling. The effect of grouting directly influences the settlement of the stratum and the stress state of the segments structure. During the construction of shield tunnels in rock mass, problems such as cutterhead deadlocking, segments floating and crack, surface subsidence, etc. would occur due to the buoyancy from synchronous backfill grouting. The cement-sodium silicate grouting can solve the above mentioned problems effectively, but meanwhile, its durability cannot be guaranteed, thus so far it has hardly been adopted in synchronous backfill grouting of shield tunnels. In the present paper, the long-term performance of cement-sodium silicate grout and its impact on segment structure in the backfill synchronous grouting during shield tunneling are systematically studied through theoretical analysis, laboratory tests, micro-analysis and numerical calculation. An evaluation method for long-term performance of cement-sodium silicate grout based on the meso-structure is proposed. Distribution form of reaction products of cement and sodium silicate grout and its change rule with the dosage of sodium silicate in cement-sodium silicate grout is revealed through the observation of meso-structure. The reduction factor of mechanical properties of cement-sodium silicate grout after degradation of the reaction products of cement and sodium silicate solution is derived with the help of stochastic finite element numerical calculation. The results reveal that when the proportion of cement and sodium silicate solution is within a certain range, the amplifications of both the internal force and deformation of segment structure are very small, even if grouting layer loses effectiveness completely. The maximum crushing stresses on the grouting layer after degradation is less than the minimum residual compressive strength, which can meet the practical engineering needs and guarantee the safety of the tunnel. Therefore, cement-sodium silicate grout is suitable for synchronous grouting in shield tunneling.

A systematic study on polymer modified alkali-activated slag – Part I: Stability analysis of colloidal polymer dispersion in sodium water glass

Colloidal stability of polymer particles in activator is the pre-condition for the application of polymer dispersion in alkali activated materials (AAM). In this study, investigation of the stability of classical cement-stable polymers (styrene acrylate (SA) and ethylene-vinyl acetate (EVA)) in the presence of sodium silicate with different moduli at varied dosages and storing times was conducted through combined techniques including laser particle analysis and ultraviolet-visible spectrophotometry (UV–Vis). It is found that SA is significantly more stable than EVA dispersions. Dosage of sodium silicate and storing time are the main factors for loss of colloidal stability of the polymer particles. The highest colloidal stability of the latexes was observed with the lowest investigated modulus (M < 1.81). Sodium sulphate alone or a combination of sodium sulphate and hydroxide ions have no effect on the colloidal stability of polymer particles. However, in the presence of sodium silicate, sodium sulphate greatly decreases the colloidal stability.

Parameterization of SiO2 Nanoparticles Preparation Route and Evaluation of the Reaction Parameters Using Fuzzy Mathematics

In this work, SiO2 nanoparticles were prepared via hydrolysis method, chemical precipitation method and sol-gel method, respectively. And the effects of various experimental conditions on the unit output, yield, particle size and size distribution of SiO2 nanoparticles were studied and parameterized. Meanwhile, a set of evaluation systems were constructed with fuzzy mathematical analysis and modeling which the complex data can be evaluated systematically with concise and precise unity. The results indicate that Si and Na2SiO3 are suitable raw materials for the industrial production of 20 nm and 60 nm SiO2 nanoparticles and the maximum weighted average can reach the high level of 81.3 and 82.95, respectively. Also, SiO2 nanoparticles with 250 nm ought to be prepared using TEOS as the raw material, and its maximum weighted average is 85. Moreover, the results also show that the order of the effects of the factors in hydrolysis is the dosage of sodium silicate > the amount of silica powder > the reaction time. For the chemical precipitation method, the order is the pH value > the reaction time > the reaction concentration. For the sol-gel method, the order is the amount of ammonia water > TEOS consumption > the reaction time.

Alkali-activated natural pozzolan/slag mortars: A parametric study

This study was devoted to assess the influence of binder' aluminosilicate precursor combination (natural pozzolan/slag combinations), activator combination (sodium silicate/sodium hydroxide combinations), sodium hydroxide concentration, and alkaline activator solution-to-binder ratio (S/B) on properties of alkali-activated natural pozzolan/slag mortars. The evaluated properties included flow, setting time, hydration heat, compressive strength, absorption, rapid chloride permeability, and drying shrinkage. The performance of alkali-activated natural pozzolan/slag mortars were also compared with the performance of Portland cement mortars. The results of this study revealed that in comparison with the Portland cement mortars, alkali-activated natural pozzolan/slag mortars generated significantly lower heat, thus offering a great benefit to mass concreting. Their hydration activity accelerated and setting time shortened with increases in sodium hydroxide concentration and dosage within the studied ranges, increases in slag portion of binder, and decreases in S/B. The compressive strengths of alkali-activated mortars were lower than those of the Portland cement mortars. It was shown, however, doable to produce alkali-activated natural pozzolan/slag mortars reaching the strength of portland cement mortars. The compressive strength improved with increases in sodium silicate dosage and reduction in S/B. Regarding compressive strength, the optimum binder combination and sodium hydroxide concentration were found to be interdependent of one another. While absorption of alkali-activated mortars was slightly higher than that of the portland cement mortars, their chloride penetration depths were significantly lower than those of the portland cement mortars. The chloride penetration depth reduced with decreases in natural pozzolan portion of binder, sodium silicate dosage, NaOH concentration, and solution-to-binder ratio. A similar trend was seen for the drying shrinkage as reduction of these variables also decreased the drying shrinkage. The drying shrinkage of the studied alkali-activated natural pozzolan/slag mortars was considerably higher than those of the portland cement mortars.

The long term engineering properties of cementless building block work containing large volume of wood ash and coal fly ash

The reuse of pulverised fuel ash (PFA) and high calcium wood ash (HCWA) offers a two folds solution towards addressing the waste management problem and reduce the carbon footprint of concrete material. In order to enable sizeable application of such recycling method to produce block work for the construction industry, a comprehensive framework of knowledge on the mechanical strength performance of the concrete product containing large volume of PFA and HCWA needs to be established. Hence, it is the primary aim of the study to report a comprehensive assessment on the mechanical strength performance of concrete block work produced with the sole use of PFA and HCWA as the primary binder phase. The PFA and HCWA binder phase with small dosage of sodium silicate was characterized in terms of its standard consistency and setting times. Besides, a thorough assessment on the mechanical strength of block work produced with PFA-HCWA binder was conducted. Mechanical strength assessment covers the compressive strength, flexural strength and velocity of ultrasonic pulse propagation through the material. Besides, the fourier transformed infrared (FTIR) assessment was also performed to characterize the aluminosilicate bonds of the primary binder phase. The increasing mass ratio of HCWA was found to raise the water demand of the HCWA-PFA binder paste. Besides, the HCWA:PFA combination ratio of 50:50 and 40:60 has been found to exhibit the optimal flexural and compressive strength performance. It has also been established that the block work produced using HCWA:PFA combination ratio between 30:70 up to 90:10 meets the California Concrete Masonry Technical Committee requirement as class N concrete block work unit.

Effect of sodium silicate on the reverse anionic flotation of a siliceous–phosphorus iron ore

Abstract In the flotation system of Chador Malu iron processing plant (Iran), the apatite is floated with fatty acid based collectors. Sodium silicate is also used as iron oxides depressant. While the phosphorous content of the iron concentrate is reduced at an acceptable level (0.047% P), the silica content (3.5% SiO 2 ) is still higher than the required level. This study aimed to find an effective reagent combination to reduce the silica and phosphorous contents of iron concentrate. Batch flotation tests were carried out to investigate the influence of sodium silicate dosage, modulus and addition of Ca ++ ions, on the separation selectivity of phosphorous and siliceous gangue minerals from iron oxides. The feed sample, with 57.20% Fe, 6.42% SiO 2 and 0.748% P was mainly composed of haematite and magnetite and the main gangue minerals were apatite and quartz. The results of flotation tests showed that sodium silicate performed better as depressant of iron oxide, but had little effect on silica flotation in the apatite–iron oxide–silica flotation system. It was also found that by using sodium silicate of modulus of 2.5 at a concentration of 800 g/t, pH value of 10, and conditioning time of 10 min, an effective separation of apatite from iron oxides could be achieved, while the silica removal ( 2 ·2H 2 O), as a source for Ca ++ ions, to the sodium silicate solution enhanced the separation selectivity of quartz and apatite from the iron oxides. Applying a silicate–CaCl 2 ·2H 2 O mixture with Me/Si ratio of 0.4, resulted in a concentration with acceptable grades of Fe (67%), SiO 2 (1.5%), and P (0.034%). In this case, 93.6% of Fe was recovered while 75% of SiO 2 and 93.9% of P were also removed.

两性捕收剂用于四川清平磷矿的正反浮选试验

为了解决四川清平磷矿因含高倍半氧化物而难以富集的问题，采用两性捕收剂SB-116对四川清平磷矿进行了正反浮选试验研究。在原矿品位为22.06%，磨矿细度为−0.074 mm含量91.6%的条件下，采用正反浮选工艺即正浮选一粗联合反浮选一粗一扫中矿顺序返回，正浮选碳酸钠用量为7.0 kg/t，水玻璃用量为1.5 kg/t，捕收剂MXO-135用量为1.2 kg/t，浮选温度为22℃，反浮选为一次粗选一次扫选，粗选硫酸用量为15 kg/t，抑制剂LMX-1用量为0.6 kg/t，两性捕收剂SB-116用量为0.25 kg/t，扫选LMX-1用量为0.3 kg/t，可以得到精矿品位P2O529.81%，产率63.26%，回收率85.49%的选矿指标。 In order to solve the problem that Sichuan Qingping phosphate is difficult to concentrate because of containing high sesquioxide, the flotation tests were conducted with amphoteric collector SB- 116 used in direct-reverse flotation of Sichuan Qingping phosphate. On the condition of ore grade 22.06%, the grinding fineness −0.074 mm 91.6%, the direct-reverse flotation process that a combination of direct flotation with one roughing and reverse flotation with one roughing, one scavenging and middlings returning was conducted. In the direct flotation, the dosage of sodium carbonate was 7.0 kg/t; the dosage of sodium silicate was 1.5 kg/t; the dosage of collector MXO-135 was 1.2 kg/t and flotation temperature was 22˚C. The reverse flotation was one roughing and one scavenging with the dosage of sulfate 15 kg/t, the dosage of inhibitor LMX-1 0.6kg/t, the dosage of amphoteric collector SB-116 0.25 kg/t in roughing and the dosage of LMX-1 0.3 kg/t in scavenging. The beneficiation indexes of concentrate grade P2O5 29.81%, yield 63.26% and recovery rate 85.49% can be obtained.

The Effect of Selective Additives on the Rheological Behavior of Power Plant Ash Slurry

The rheological behavior of power plant ash samples collected from JSPL (M/s Jindal Steel & Power Limited, Raigarh), India, was carried out using a HAAKE rotational rheometer (Model: RheoStress 1, Thermo Fisher Scientific). The ash slurry indicated non-Newtonian behavior in the solids concentration range of 50–60% by mass. The rheological data were best fitted by Bingham plastic model in the studied ranges of concentrations and shear rates. Two selective additives, namely sodium silicate and Ghadi detergent, were applied in small quantities (0–0.6% of total solids) and their effects on rheological parameters were evaluated. It was indicated that the small dosage of sodium silicate substantially influenced the Bingham parameters of the ash slurry than the Ghadi detergent. The percentage reduction in Yield stress at a slurry concentration of 60% by weight were found to be 59.3% and 46.23% for sodium silicate and Ghadi detergent, respectively, at a maximum dosage of 0.6% additives. More importantly, the plastic viscosity reduced by 37.6% and 16.3%, respectively, with the same dosage of sodium silicate and Ghadi detergent at same slurry concentration.

Study on the early Hydration of Alkali-Activated Slag Cementing Materials

The early hydration of alkali-activator slag(AAS) cementing material is studied by changing the environment temperature, the proportion of slag and fly ash, water glass module, and dosage of sodium silicate. The results show that as the temperature raise, the hydration rate and hydration heat of the AAS cementing materials will remarkably accelerate. Joining coal ash in the pure slag cementing material can effectively slowdown its hydration reaction, and the hydration heat is also reduced.

Optimization Study on Flotation Conditions of Complex and Refractory Lead Oxide Ores

The optimization condition of flotation reagents of complex and refractory lead oxide ores from Yunnan was studied in this paper. Based on the research on the properties of the material, the grinding fineness and reagent dosages were investigated and a technological flowsheet consisting of one roughing flotation, two scavenging flotation and two concentrate flotation was adopted. The optimum parameters of flotation experiment were determined as grinding fineness of 85%, dosage of sodium silicate at 800 g/t, dosage of Na2S at 1200 g/t and dosage of isoamyl xanthate at 600 g/t. Under such a condition, a lead recovery of 76.55% with a concentrate grade of 58.67% was obtained, which effectively improved utilization of lead resource.

Influence of sodium silicate modulus on iron ore flotation with sodium oleate

This paper presents the influence of sodium silicate modulus on iron ore flotation with sodium oleate collector. Bench flotation tests were performed at pH7 with actual iron ore from Quadrilátero Ferrífero, Brazil, with 42.8% Fe and 37.2% SiO2. Iron recovery averaged above 90% and the Fe contents in the concentrate were above 55%. The highest values of Fe grade and lowest of SiO2 were obtained with low levels of pulp density and sodium silicate dosage and with high level of sodium oleate. Increase of sodium silicate modulus had a small influence on response variables.

Roughing Conditions Research to Recover a Nickel Ore

The ore from Jingping contains 0.634% nickel, 0.329% copper, 0.047% cobalt, 30.18% SiO2and 19.72% MgO. In order to obtain satisfying beneficiation results, a lot of tests were taken out before, and this article main focus on roughing flotation conditions. Finally find that when the sodium carbonate dosage is 2000g/t, carboxy-methyl cellulose (CMC) dosage is 200g/t, sodium silicate dosage is 100g/t, the combinational effect can depressing the gangue minerals as well as the slime. The final concentration contains 3.03% nickel, 2.01% copper and 2.40% cobalt, the recovery of the nickel, copper and cobalt is 73.03%, 92.58%, 77.62% respectively.

Research of the Complex Copper Slag Flotation Experiment

A kind of complex Copper slag has been studied. The run-of-mine grade of copper was 0.93%. Through the research of the flotation separation test, the optimal grinding fineness (-0.074mm) was about to 75%. The optimum kind and dosage of collector was 150 g/t Y89. The dosage of sodium silicate which was the Slime dispersing agent was 1000g/t. The dosage of sodium carbonate was 800g/t.

Effect of sodium silicate on the solubility of zinc oxide of the Na2O–ZnO–H2O equilibrium system

Abstract There is a competitive reaction of zinc and silica in the alkali leaching process of zinc oxide ore, leading to low zinc leaching rate. To increase leaching rate of zinc, the effect of sodium silicate on the solubility of zinc oxide of the Na 2 O–ZnO–SiO 2 –H 2 O equilibrium system is studied by adding Na 2 SiO 3 and ZnO to NaOH solution. Results show that zinc oxide equilibrium concentration increases with temperature from 25 to 75 °C at the same molar ratio of Na 2 O to SiO 2 . The equilibrium concentration of zinc oxide initially increases and then declines with the increasing concentration of Na 2 O. This leads to the maximum ZnO concentration, which increases with temperature but decreases with the increasing dosage of sodium silicate. The precipitate of disodium zinc silicate (Na 2 (ZnSiO 4 )) generates due to the reaction of silicate SiO 3 2 − and Zn(OH) 4 2 − in the solution of Na 2 O–ZnO–H 2 O equilibrium system. High zinc leaching rate can be obtained when the Na 2 O concentration is lower than the values indicated by the “peak” points at higher molar ratios of Na 2 O to SiO 2 and temperatures.

The Experimental Research on the Sedimentation Performance of one Molybdenum Ore Flotation Tailings

This paper adopts sedimentation experiment to study the sedimentation process of one molybdenum ore flotation tailings and to investigate the effects of lime and sodium silicate on sedimentation performance of tailings. Through the experiment on sedimentation speed and compressive layer density, it reveals the sedimentation performance rules of these tailings. Meanwhile, it explores the effects of lime and sodium silicate on sedimentation dry beach of tailings. The research shows that: lime could effectively ameliorate the non-easy sedimentation caused by sodium silicate; when the dosage of sodium silicate is 300～800g/t, the sedimentation performance can reach the best reasonable pH value 9-10. Besides, the study also indicates that both sodium silicate and lime are unfavorable to form sedimentation dry beach by tailings of concentrating mill.

Optimization of process parameters for producing graphite concentrate using response surface methodology

The optimization of process parameters for the production of a graphite concentrate was developed using response surface methodology (RSM). The relationship between the responses, i.e. total carbon grade and recovery, and four process parameters, i.e. kerosene dosage, sodium silicate dosage, agitation speed and scrubbing time were presented as empirical model equations for graphite concentration. The model equations were then optimized using the quadratic programming method to maximize total carbon grade and recovery within the experimental range studied. The optimum conditions were found to be 680 g/t kerosene, 500 g/t sodium silicate, 1500 rpm agitation speed and 75 min scrubbing time to achieve the maximum total carbon grade. The model prediction of 94.9% total carbon grade at these optimum conditions is higher than any value obtained in the experiments conducted. Similarly, the conditions for maximum total carbon recovery were found to be 807 g/t kerosene, 162 g/t sodium silicate, 987 rpm agitation speed and 36 min scrubbing time. The model prediction of 96.4% total carbon recovery at these optimum conditions is also higher than any value obtained in the experiments conducted. This study indicates that the response surface methodology was useful in improving the production of graphite concentrate.

Desempenho físico-mecânico de minipainéis de terra crua tratada com aditivos químicos

O presente trabalho teve como objetivo pesquisar o efeito da incorporação ao solo de estabilizantes químicos (cal e cimento) associados ao silicato de sódio. Os tijolos foram moldados e assentados na forma de minipainéis que tiveram suas características físico-mecânicas determinadas em laboratório e seu comportamento tecnicamente avaliado por meio de métodos destrutivos e não-destrutivos (método acústico do ultra-som). Foram pesquisados um solo arenoso e outro siltoso. Os teores de cimento e cal adicionados foram de 6% e 10% em relação à massa seca do solo, e o teor de silicato de sódio foi de 4% em relação à massa seca de solo-cimento ou solo-cal. Os tijolos foram prensados e colocados em câmara úmida por 7; 28; 56 e 91 dias. Aos 28; 56 e 91 dias, os minipainéis foram submetidos ao ensaio de ultra-som para a obtenção do módulo de elasticidade dinâmico, seguido do ensaio de compressão simples. Os melhores resultados, em termos de resistência à compressão simples, capacidade de absorção de água e propriedades elásticas (módulo dinâmico), foram obtidos pelo solo arenoso adicionado de 10% de aglomerante associado ao silicato de sódio. De forma geral, os resultados sugerem uso promissor do silicato de sódio para a melhoria das propriedades físico-mecânicas relacionadas à resistência e à durabilidade de tijolos de terra crua.

Eficiência da estabilização do solo e qualidade de tijolos prensados de terra crua tratada com aditivos químicos, avaliadas pela combinação de testes destrutivos e não-destrutivos

A qualidade de tijolos prensados de terra crua tratada quimicamente é influenciada basicamente pelo tipo de solo, adições químicas e período de cura. O presente trabalho teve como objetivo estudar a combinação de métodos destrutivos e não-destrutivos associados à análise estatística, para a avaliação da qualidade e da eficiência da estabilização de tijolos prensados de terra crua tratada com cimento, cal e silicato de sódio. Os teores de cimento e cal foram 0; 6 e 10%, e a dose de silicato de sódio foi de 4% em relação ao peso seco da mistura solo-aditivo. Após a sua moldagem, os tijolos foram submetidos à cura durante os períodos de 7; 28; 56 e 91 dias. As propriedades físico-mecânicas dos tijolos foram determinadas por meio de testes destrutivos, tais como a resistência à compressão simples e a absorção de água, e não-destrutivos por meio do ensaio acústico do ultra-som. Adotou-se o parâmetro "resistência anisotrópica" para simplificar as interpretações estatísticas. A adição química que conferiu a melhor qualidade técnica aos tijolos, foi a de 10% de cimento. O parâmetro resistência anisotrópica mostrou-se promissor com vistas à avaliação da qualidade técnica dos tijolos.

J. Mater. Science Letters

This paper presents the influence of sodium silicate modulus on iron ore flotation with sodium oleate collector. Bench flotation tests were performed at pH 7 with actual iron ore from Quadrilátero Ferrífero, Brazil, with 42.8% Fe and 37.2% SiO2. Iron recovery averaged above 90% and the Fe contents in the concentrate were above 55%. The highest values of Fe grade and lowest of SiO2 were obtained with low levels of pulp density and sodium silicate dosage and with high level of sodium oleate. Increase of sodium silicate modulus had a small influence on response variables.