Effect Of Pumice Research Articles

Role of different natural materials in reducing nitrogen loss during industrial sludge composting: Modelling and optimization

In this study, the effects of pumice, expanded perlite, and expanded vermiculite on nitrogen loss were examined for industrial sludge composting using the Box-Behnken experimental design. The independent factors and their levels were selected as amendment type, amendment ratio, and aeration rate, and codded as x1, x2, and x3 at 3 levels (low, center, and high). The statistical significance of independent variables and their interactions were determined at 95% confidence limits by Analysis of Variance. The quadratic polynomial regression equation produced to predict the responses was solved and the optimum values of the variables were predicted by analyzing the three-dimensional response surfaces plots. The optimum conditions for minimum nitrogen loss by the regression model were as pumice of amendment type, 40% of amendment ratio, and 6 L/min of aeration rate. In this study, it was observed that time-consuming and laborious laboratory work can be minimized with the Box-Behnken experimental design.

Improvement of Shear Strength of Zeolite-Bentonite Liner Material under High Temperatures with Tincal and Pumice

Thermal changes (high temperature and thermal cycles) occur around energy structures, such as energy piles, nuclear waste repositories, etc. Sometimes these temperature changes affect the engineering properties of surrounding soils undesirably. Hence, there is a need for durable soils that can maintain their engineering properties unchanged under high temperature and thermal cycles for a long time. Tincal and pumice are used in the production of temperature-resistant and heat-insulated materials. Therefore, in the present study, 10% and 20% tincal and pumice additives were added to zeolite-bentonite mixtures and shear strength behavior of the mixtures was investigated under room and high temperatures (80°C). According to the results, the maximum shear stress values of zeolite- bentonite mixtures generally increased in the presence of tincal and pumice additives under high temperature. Both additives are effective for improvement, however; the effect of pumice can be more pronounced.

The Effects of Pumice on the Morphological Characteristics, Yield and Some Quality Parameters of Banana in Cultivation

Türkiye’de muz yetiştiriciliğinde üretim maliyetini arttıran en önemli unsurlardan birisi çiftlik gübresi kullanımıdır. Çiftlik gübresi fiyatının yüksek olması yanında, her zaman kalitede standartı yakalamak güçtür. Bu çalışmada, açıkta muz yetiştiriciliğinde pomza taşı kullanımının verim ve kaliteye etkileri incelenmiştir. Araştırmada çeşit olarak Dwarf Cavendish (AAA) çeşidi kullanılmış ve pomza taşının bitki başına 5 kg, 7.5 kg ve 10 kg dozları denenmiştir. Çalışmada, bitki morfolojik özellikleri (gövde çevresi, yaprak sayısı, gövde yüksekliği, hevenk sapı çevresi), meyve gelişme süresi, verim ve verim bileşenleri (tarak ve parmak sayısı, parmak ağırlığı, çevresi ve uzunluğu) ile bazı kalite kriterleri incelenmiştir. Araştırma bulguları, uygulamaların kontrole göre bitki morfolojik özelliklerinden sadece gövde yüksekliği ve hevenk sapı çevresini istatistiksel olarak etkilediğini, verim ve meyve kalite kriterlerinin hepsini olumlu yönde etkilediğini göstermiştir. Verim ile doğrudan ilişkili olan tarak sayısı, parmak sayısı, parmak ağırlığı ve hevenk ağırlığı pomza düzeyi arttıkça artış göstermiştir. Hektara verim kontrol uygulamasında 55.84 ton ve 10 kg pomza uygulamasında ise 62.93 ton olarak kaydedilmiştir. Ayrıca pomza uygulamalarının kontrol uygulamasına göre meyve gelişim süresini de kısalttığı tespit edilmiştir. Buna ilave olarak, pomza uygulamaları kalite kriterlerinden sakkaroz miktarını arttırdığı tespit edilmiştir. Araştırma sonucunda, açıkta muz yetiştiriciliği yapılan alanlarda pomza kullanımının verim ve kaliteyi kontrole göre arttırdığı belirlenmiştir. İncelenen tüm özellikler ve maliyet dikkate alındığında, açıkta muz yetiştiriciliğinde bitki başına 7.5 kg pomza uygulaması tavsiye edilmiştir.

Study on Effects of Pumice in High Performance Light Weight Concrete by Replacing Coarse Aggregates

Pumice is a rock particle that was used in this experiment’s concrete, and light weight aggregate is a type of aggregate that is lighter than natural aggregate. The major purpose of the suggested methodology is to use optimization techniques to frame a mathematical model. Structural lightweight concrete is used extensively in the construction sector, particularly in high-rise buildings. Only lightweight aggregates can be used to make it. Pumice is a solid component and a highly porous rock light in nature that can be used as an alternative to coarse aggregate (CA) in concrete and Nano Silica an alternative for cement. This lightweight aggregate, on the other hand, has a higher density than other natural and artificial lightweight aggregates. As a result, the density of concrete made with this lightweight aggregate is relatively high, falling into the semi-lightweight concrete category. According to the latest analysis, to further at the density of an lightweight concrete with high strength, Pumice was partially replaced with a coarse aggregate. In this study, pumice was substituted for CA in percentages of 0%, 20% and 30% by quantity and Nano Silica replaced in 1-3% for different mixes to predict three output parameters such as compressive strength (Mpa), split tensile strength (Mpa), flexural strength (Mpa). The addition of pumice to CA concrete decreases density while also lowering all mechanical properties, according to test results. This is because pumice has a smooth surface texture and has a lower density than CA. On the other hand, lightweight concrete containing more than 20% pumice changes into structural lightweight concrete with excellent strength. Several studies demonstrated an overall gain in strength as well as weight loss. As a result, light-weight concrete is equal to heavy-weight concrete in terms of strength.

A comparative analysis on the effects of pumice, tuff and conventional aggregates on energy efficiency performance in new generation composite mortars

It is often stated that there is an energy efficiency gap between optimal energy use and actual energy use in the world. In the construction sector, various building materials are produced to optimize energy efficiency in buildings. Among these construction materials, cement mortars are widely used. Cement mortars are produced from various raw materials and aggregates. The aggregates, which are volcanic and porous property between these aggregates, have high insulation properties due to their porous structures. In this study, two different volcanic porous aggregates with suitable unit weight and pore structure for thermal insulation were used in cement mortar. At the end of the experimental study, the thermal behaviour of the cement mortars produced was investigated. According to the results of the research, it was determined that the cement mortar produced with pure pumice was the most suitable for the heat insulation between the tested aggregates.

The effect of pumice and clay composition in natural rubber-ethylene propylene diene monomer blends towards its curing characteristics and physic-mechanical properties

Since some adverse effects of using carbon black as petroleum-based filler in rubber compounding, mineral fillers may be a feasible alternative filler. This research studied the effect of the composition of pumice and clay as mineral filler in natural rubber (NR) and ethylene propylene diene monomer (EPDM) blending towards its curing characteristics and physical-mechanical properties. The effect of reinforced filled in EPDM-NR (70/30) phr blends was observed by varying 50, 70, and 90 phr of filler. While the filler was designed as the composition of pumice/clay (P/C): 20/80; 50/50; 80:20 (weight/weight). The rubber, fillers, and chemical were compounded based on ASTM D-3182. The results showed that the loading of P/C fillers in EPDM-NR blends increased scorch time and decreased cure rate index. It was found that the optimum number of filler could enhance density, modulus. Remarkably, the higher pumice composition caused the abrasion resistance and compression set improved significantly, whereas the overloading pumice and clay cause the physic-mechanical properties remained stable or evenly drop. FTIR spectra of the binary blends confirmed that the fine fillers dispersion was obtained due to some interaction bonding between silanol, aluminol of fillers with the EPDM-NR.

Tamaño de partícula de Pumita y Tezontle en el crecimiento de plantas de Ocimum Basilicum L.

There are few reports about the effect of pumice in the production of basil (Ocimum basilicum L.), an economically significant plant. The size of pumice particles can influence basil production. The objective of this study was to compare the growth and production of basil plants cultivated using pumice and tezontle particles of various sizes. Pumice (jal) and tezontle were mined in Xalisco, Nayarit. Five particle sizes per material were used —size 0 = 0.1≥ ≤12 (material without particle separation); size 1 = 7.5 ≥ ≤12; size 2 = 5.0≥ <7.5; size 3 = 3.0≥ <5.0; size 4 = 0.8≥ <3.0; size 5 = 0.1≥ <0.8— and their physical properties were determined. The basil was transplanted into pots which had been filled with particles of each size. The following variables from the above-ground part of the plants were evaluated: plant height, stem diameter, and leaves, stem, inflorescence, and total dry mass; root variables were also evaluated. Size-4 particles recorded the highest values for height, stem diameter, and total dry biomass; this result was attributed to physical properties. The highest value was obtained for every variable aboveground when pumice substrate was used.

The effect of pumice as aggregate on the mechanical and thermal properties of foam concrete

Pumice is a porous rock, which is formed as a result of volcanic activity and does not include any crystal water. Its porous structure makes it lightweight and provides advantage for heat and sound isolation. Foam concrete is a type of lightweight concrete. Foam concrete is obtained by adding the foam obtained from the agent to the mixture of cement, water, and aggregate. Foam concrete is an environmentally friendly structure and insulation material which provides light, heat, and impact sound insulation that can be used in place of the building elements used in the interior-exterior walls and floors of all buildings. Because of the lack of coarse aggregate in the foam concrete mix, it has some structural problems and this limits its usage area. In this study, four different types of pumice aggregates and stone powder were used to overcome the structural problems of foam. The cement dosages (250 kg/m3), aggregate amounts (250 kg/m3), fresh concrete densities and w/c ratio (0.45) were kept constant in all foamed concrete mixtures. Then, physical, mechanical, and thermal conductivity properties of the resulting foam concretes were investigated. When the findings were evaluated, the most suitable type of lightweight aggregates for use in foam concrete have been determined in terms of compressive strength and thermal conductivity properties. In all aggregate groups, Nevsehir Pumice has the highest compressive strength while Karaman Pumice has the lowest thermal conductivity. However, when both properties were evaluated together, it was determined that the most favorable lightweight aggregate was Nevsehir Pumice.

Retracted: Durability Characteristics of Self-Compacting Concrete Incorporating Pumice and Metakaolin

AbstractIn this study, the effects of pumice and metakaolin (MK) on the durability and microstructural properties of self-compacting concrete (SCC) are investigated. A total of 10 mixtures includin...

The effect of pumice on reduction of cadmium uptake by spinach irrigated with wastewater

Increasing demand for irrigation water and scarcity of fresh water has caused significant increase in the reuse of urban and industrial wastewater throughout the world. Heavy metals in wastewaters are the main factors in the contamination of water and soil. The objective of this study was to evaluate the effect of application of pumice as soil amendment on the uptake of Cd by spinach (Spinach oleracea L.) under irrigation with wastewater (containing 10mg/L Cd). The experiment was conducted as a completely randomized design in a greenhouse with 3 replications in the research station of Isfahan University of Technology. Different levels of pumice (0, 4% and 8% w/w soil) were added to the soil. Results indicated that the addition of 4% and 8% of pumice in soil, decreased 30.19% and 46.17% Cd uptake in plants, respectively. The transfer factor into roots and shoots of spinach were significantly reduced (p<0.05) in pumice treatments compared to the control. The percentage of DTPA extractable Cd in soils amended with pumice significantly decreased (p<0.05) and this resulted in lower Cd accumulation in plants. Irrigation with wastewater containing Cd decreased the yield in comparison to irrigation with freshwater. So, it seems that pumice, as a cost-effective adsorbent, poses potential for immobilization and reduction of phytoavailability of Cd in polluted soils.

Effect of Pumice and Sand on the Sustainability of Granular Iron Beds for the Aqueous Removal of CuII, NiII, and ZnII

AbstractCurrent knowledge of the basic principles underlying the design of Fe0 beds is weak. The volumetric expansive nature of iron corrosion was identified as the major factor determining the sustainability of Fe0 beds. This work attempts to systematically verify developed concepts. Pumice and sand were admixed to 200 g of Fe0 in column studies (50:50 volumetric proportion). Reference systems containing 100% of each material have been also investigated. The mean grain size of the used materials (in mm) were 0.28 (sand), 0.30 (pumice), and 0.50 (Fe0). The five studied systems were characterized (i) by the time dependent evolution of their hydraulic conductivity (permeability) and (ii) for their efficiency for aqueous removal of CuII, NiII, and ZnII (about 0.3 mM of each). Results showed unequivocally that (i) quantitative contaminant removal was coupled to the presence of Fe0, (ii) additive admixture lengthened the service life of Fe0 beds, and (iii) pumice was the best admixing agent for sustaining permeability while the Fe0/sand column was the most efficient for contaminant removal. The evolution of the permeability was well‐fitted by the approach that the inflowing solution contained dissolved O2. The achieved results are regarded as starting point for a systematic research to optimize/support Fe0 filter design.

The effects of pumice aggregate/cement ratios on the low-strength concrete properties

Lightweight concretes can be produced by using processed natural material, processed by-product or unprocessed porous materials, depending upon the requirements of density and strength levels. The present study covers the use of pumice lightweight aggregate (PLA) to produce the lightweight concrete (LWC) for use in construction of load-bearing or non-load bearing elements. In this study, pumice aggregate lightweight concrete (PALWC) blocks were produced with different sizes of 8–16 mm as coarse pumice aggregate (CPA), of 4–8 mm as medium pumice aggregate (MPA) and 0–4 mm as fine pumice aggregate (FPA). According to the preliminary trial batch results, the optimum grade of aggregates was determined as 25% FPA, 25% MPA and 50% CPA by weight for the mixture compositions. The pumice aggregates were obtained from a pumice quarry in Isparta region, Turkey. To analyse the effects of CPA, MPA and FPA/cement ratios on the non-structural concrete engineering properties, the range of different pumice aggregate/cement (A/C) ratios of 6:1, 8:1, 10:1, 15:1, 20:1, 25:1 and 30:1 by weight and cement contents of 180, 137, 110, 72, 52, 40 and 32 kg/m 3 were used to make PALWC mixture testing samples with a slump of from 2 to 4 cm. The properties of PALWC with the range of different pumice aggregate/cement ratios were evaluated by conducting comprehensive series of tests on workability, compressive strength, elasticity modulus, bulk density, wetting expansion, drying shrinkage, water absorption and thermal conductivity. Experimental test results showed the PALWC up to 25:1 A/C ratios has sufficient strength and adequate density to be accepted as load-bearing block applications. Further, higher than 25:1 A/C ratio has sufficient strength, adequate density and the thermal conductivity to be accepted as non-load bearing infill blocks for insulation purposes. PALWC showed the design flexibility and substantial cost savings by providing less dead load due to its lower density values. The properties, which increase in value and indicate the increasing quality with lower A/C ratios (high cement contents), are compressive strength, modulus of elasticity and density. Properties, which decrease in value, with higher A/C ratios are water absorption, wetting expansion, drying shrinkage and thermal conductivity. It was experienced that lowering the A/C ratios increases strength quality of PALWC. But, increase of the A/C ratio increases the thermal insulation property. Basically, the research showed that non-structural lightweight concrete can be produced by the use of fine, medium and coarse pumice aggregates mixes without using any additions or admixtures.

Effect of pumice and fly ash incorporation on high temperature resistance of cement based mortars

The effects of high temperature on the mechanical properties of cement based mortars containing pumice and fly ash were investigated in this research. Four different mortar mixtures with varying amounts of fly ash were exposed to high temperatures of 300, 600, and 900 °C for 3 h. The residual strength of these specimens was determined after cooling by water soaking or by air cooling. Also, microstructure formations were investigated by X-ray and SEM analyses.Test results showed that the pumice mortar incorporating 60% fly ash revealed the best performance particularly at 900 °C. This mixture did not show any loss in compressive strength at all test temperatures when cooled in air. The superior performance of 60% FA mortar may be attributed to the strong aggregate–cement paste interfacial transition zone (ITZ) and ceramic bond formation at 900 °C. However, all mortar specimens showed severe losses in terms of flexural strength. Furthermore, specimens cooled in water showed greater strength loss than the air cooled specimens. Nevertheless, the developed pumice, fly ash and cement based mortars seemed to be a promising material in preventing high temperature hazards.