Addition Of Dolomite Research Articles

Fabrication and Properties of Adsorptive Ceramic Membrane Made from Kaolin with Addition of Dolomite for Removal of Metal Ions in a Multielement Aqueous System.

The exorbitant presence of heavy metals has emerged as one of the most serious ecological issues facing the world. The treatment processes currently employed are not effective for removing all of the contaminants completely. Therefore, it is necessary for better operational technology to be developed. Here, we fabricated effective and inexpensive kaolin-based ceramic membranes with the addition of dolomite using a simple dry compaction method. Moreover, we applied the obtained adsorptive membranes to the removal of lead, copper, zinc, and cadmium from aqueous solutions. The membranes prepared with dolomite addition (sintered at different temperatures) exhibited a high water flux between 246.78 and 1738.56 L/h·m2 at an extremely low operating pressure (0.03 MPa). Furthermore, the optimal membrane showed high removal efficiencies of 99.12, 99.82, 85.62, and 65.94% for Pb(II), Cu(II), Zn(II), and Cd(II), respectively. The utilization of dolomite enhanced the removal efficiency of the adsorptive membranes by around 32-54% in a multielement system. This work reveals that enhanced adsorptive membranes with high fluxes and strong removal abilities have great potential as a synergized system with practical applications in the removal of heavy-metal contaminants from wastewater in the future.

Exploring the Impact of Biochar‐Dolomite Application at Different Pyrolysis Temperatures on Acid Sulfate Soil Properties

ABSTRACTThe use of biochar as a soil amendment for acid soil, particularly acid sulfate soil, has garnered significant interest due to its capacity to improve soil properties, which is further accentuated when combined with dolomite. However, the extent to which the magnitude and direction of this effect vary with biochar produced at different pyrolysis temperatures remains uncertain. We conducted an incubation by mixing soil with dolomite and biochar types derived from Melastoma malabathricum (MMBC) and Dicranopteris linearis (DLBC) at three temperatures (300, 500, and 700°C). The incorporation of dolomite with both biochar types led to significant improvements in soil pH, available P, available Fe, exchangeable K, and exchangeable Ca compared to soil amended with dolomite only. These enhancements were likely attributed to the release of alkalinity, which further raised soil pH, as well as the direct dissolution of P, K, and Ca from the biochar. Moreover, the reduced Fe availability was likely due to the complexation of Fe onto surface functional groups of biochar. Furthermore, these improvements surpassed the effect of the initial feedstock and became increasingly pronounced with higher pyrolysis temperatures. However, an antagonistic effect of dolomite and biochar co‐incorporation was observed, particularly in the relative reduction of soil exchangeable Mg with both biochar types, and a decrease in the soil available N with MMBC produced at 300 and 500°C compared to dolomite addition alone, which could be due to the adsorption of Mg and N onto biochar surface. The results indicate that concurrent application of dolomite and biochar can change the acid sulfate soil properties to varying magnitudes and in different directions, largely regulated by the characteristics of biochar as well as the probable interplay with dolomite. Consequently, selecting the appropriate biochar that aligns with the desired soil properties is crucial in managing dolomite‐treated acid sulfate soil.

Enhanced syngas production from wood biomass by the catalytic packed bed of dolomite, limestone and olivine

Wood biomass was a promising renewable energy source that achieved carbon neutrality and alleviated the energy crisis. To enhance the conversion efficiency of wood to hydrogen, the catalytic combustion system of natural ores (dolomite, limestone and olivine) and wood chips was established. And the effects of the type, location, calcination temperature, content and diameter of catalysts were investigated on the temperature distribution and gas production. The results indicated that the combustion temperature of the hybrid bed was significantly increased with the catalyst addition. The dolomite and limestone particles promoted the hydrogen production, and the mole fractions of hydrogen were improved by 75% and 42%, respectively. When the dolomite was located above the wood layer, the hydrogen fraction was greatly higher than that of mixing with the wood. As the dolomite content increased, both of the hydrogen mole fraction and release time were enlarged obviously. Furthermore, the wood chips and dolomite particles with smaller diameters contributed to syngas production. And the hydrogen decreased with the increasing of air velocity when dolomite addition, which achieved the maximum of 11.2% at the velocity of 2 cm/s.

Tillage Practices and Liming: Comparative Study of Soil Properties and Forage Corn Production

Tillage conservation practices (CA), traditional agriculture (TA), and liming influence soil properties and crop yield. However, it is essential to demonstrate which tillage and liming practices improve soil properties and forage corn yield. This study compared soil properties and forage corn production in two tillage systems with the addition of dolomite and lime, which formed four treatments. The tillage in the first three days surpassed the TA soil CO2 emission, with 64.8% more CO2 than in the CA soil, and the TA hydraulic conductivity and bulk density were more suitable than those in the CA soil. The CA soil had 233 earthworms m−2 more than in TA. The TA green forage corn yielded 6.45 t ha−1 more than in CA, with a higher P, Ca, and Mg foliar content than in CA, but in the CA, the foliar N and K were higher than in TA. The liming increased soil cations (except K), highlighting the lime on dolomite with—52% Al and + 4.85 t ha−1 of forage corn compared to the control. Soil CO2 emission was far lower in CA than in TA, with a slightly lower forage yield, and other soil properties were improved, meaning lower land preparation costs and time savings than in TA. Lime improved acidic soil faster than dolomite, generating higher forage yields.

Preparation of diatomite-based porous ceramics containing interlayer porous MgO by low-temperature sintering for integration of high strength and low thermal conductivity

In this work, hierarchical porous ceramics based on diatomite with both high strength and low thermal conductivity were prepared by low-temperature sintering using modified diatomite and dolomite as the main raw materials. In particular, dolomite served both as a pore-forming agent to produce CO2 gas and as a ceramic component to produce porous MgO in situ. The prepared porous ceramics exhibited a hierarchical pore structure, retaining 2–300 nm nano-pores of the diatomite itself while using dolomite decomposition to produce 1–10 µm macro-pores and porous MgO with inter-layer pore sizes of 50–300 nm. The main phases of porous ceramics were cristobalite phase, pyroxene phase, wollastonite phase and MgO phase with special structure. The effect of dolomite addition on the mechanical properties and thermal insulation of porous ceramics was investigated. It was found that the addition of 30% dolomite resulted in a porous ceramic with a porosity of 59.8% and the most favorable pore size distribution. At this time, the presence of wollastonite and pyroxene-like products in the porous ceramics contributed to the highest compressive and bending strengths of 29.66 MPa and 7.22 MPa, respectively. The lowest thermal conductivity of the porous ceramics reached 0.094 W·m−1K−1, which can be attributed to the synergistic effect of the hierarchical pores and the increasing interfacial thermal resistance. Overall, the prepared hierarchical porous ceramics exhibited great potential as an alternative material to ceramic fiber insulation in high-temperature kilns.

Manufacturing of Fired Clay Bricks for Internal Walls with Dolomite Residue as a Secondary Material

Alternative materials need to be mapped, characterized, and valued in order to reduce clay usage. A study was conducted on the utilization of waste dolomite material from a mirror manufacturing factory in the production of bricks where the factory disposes 2500 tons of dolomite waste annually. Dolomite residue was mixed with clay raw material in various mass ratios of 90/10, 87.5/12.5, 85/15, and 82.5/17.5 wt%, extruded with proper moisture content, dried at 110 °C, and fired at 1000 °C and 1100 °C. The addition of dolomite resulted in an efflorescence on the surface of the bricks while also providing thermal insulation advantages and higher fire resistance. The addition of dolomite allowed for an increase in firing temperature to 1100 °C, which was initially not possible due to the melting characteristics of the clay. Dolomite also decreased the density of the bricks, which is crucial in order to decrease the dead load in structures. The produced bricks are intended for internal wall applications because of the efflorescence on the surface of the bricks. Overall, the addition of dolomite improved thermal conductivity and density, and other characteristics also showed suitable results.

Experimental Investigation of Mechanical and Microstructural Properties of Concrete Containing Bentonite and Dolomite as a Partial Replacement of Cement

In this study, the effect of bentonite (BT) and dolomite (DT) on the mechanical and microstructural properties of concrete was evaluated on nine mixes. Cement was replaced with bentonite and dolomite by weight with varying mix ratios. The mixes are divided as M1 (Control mix), M2 (2.5% BT), M3 (2.5% DT), M4 (5% BT), M5 (5% DT), M6 (10% BT), M7 (10% DT), M8 (2.5% BT and 2.5% DT), and M9 (5% BT and 5% DT). Concrete specimens were subjected to mechanical and microstructural analysis tests. Mechanical test results show that the addition of bentonite (2.5%, 5%, and 10% ) leads to an increase in compressive strength (6.31%, 8.94%, and 13.15%) respectively. Similarly, the addition of 2.5% and 5% dolomite enhanced compressive strength by 10.52%, and 8.94% respectively, however, the addition of 10% dolomite reduced compressive strength by 6.8%. Replacement of cement with dolomite and bentonite individually also showed a small contribution to flexural and split tensile strength. Microstructural analysis shows that the addition of bentonite and dolomite filled the microstructure and refined the internal pores contributing to compressive strength. In addition, the replacement of cement with bentonite and dolomite enhanced the formation of CSH gel.

Portland cementitious coating with autogenerated oxide film and its anticorrosion behavior on magnesium alloy

A simple one-step anticorrosion Portland cement (PC)-based coating with an autogenerated oxide film on the surface of Mg alloy was successfully prepared in this study. The anticorrosion of coated Mg alloys was assessed by several electrochemical methods including open circuit potential, electrochemical impedance spectroscopy, and cyclic potentiodynamic polarization. The morphology and composition of PC-based coatings were characterized via scanning electron microscopy and X-ray diffraction. The composition of the autogenerated oxide film was analyzed via X-ray photoelectron spectroscopy. Results show that the PC-based coatings can significantly enhance the corrosion resistance of AZ41 Mg alloy due to the synergetic effect of PC-based coating and autogenerated oxide film. Particularly, the quality of oxide film plays a dominant role in determining anticorrosion of Mg alloy. Furthermore, the addition of metakaolin and dolomite enhances the resistance of PC-based coating and meanwhile, MoO42– ions from PC-based coating can adsorb in the oxide film, improving the quality of the oxide film.

Thermodynamic modelling of steelmaking slag to reduce refractory consumption during CONARC® process

ABSTRACT CONARC® steelmaking process which combines the basic oxygen and electric arc furnace steelmaking, requires precise operation and control of slag chemistry within an optimum range to reduce the refractory wear. The target slag should be MgO saturated, containing solid particles of magnesium wustite which ensures good foamy slag and causes less erosion of MgO-C refractory. In this present study, FactSage™ software was utilized to study and visualize the MgO saturation of slag through MgO-SiO2-FeO-CaO-Al2O3-MnO and CaO-SiO2-FeO-MgO-Al2O3-MnO systems. The ternary phase diagrams revealed, the slag was MgO-under saturated based on the current pattern of calcined lime and dolomite addition during the process. Based on the findings of this study, the addition pattern were altered to bring the slag regime within the MgO saturation level with good slag basicity. This change showed significant improvement in reducing the erosion rate of MgO-C lining in furnace and thereby reducing the specific gunning mass requirement.

Effect of Dolomite Addition on The Performance of Palm Oil Mill Fly Ash for Methylene Blue Adsorption

The use of palm oil mill fly ash (FA) as a low-cost adsorbent is one of the solutions for handling FA waste. In this study, the addition of dolomite is expected to improve the adsorbent performance. The aim of this study was to investigate the optimum FA-dolomite adsorbent composition and operating conditions for methylene blue adsorption. Different parameters were studied to optimize adsorption process such as the amount of dolomite, methylene blue flow rate, bed height and number of trays. FA-dolomite was converted into nano-adsorbent by sol-gel method which was coated on zeolite surface. Nano-adsorbents were characterized by XRF, FTIR, XRD and SEM. The adsorption capacity was tested by Spectrophotometer UV-Vis. XRF characterization showed that FA had the highest SiO2 content of 58.15%, while dolomite contained CaO of 52.72%. FTIR characterization detected the groups of Si-O-Si, Si-O-Al, Ca-O and Si-O. XRD characterization showed the average crystalline size of FA-dolomite 2% adsorbent was 28.56 nm and SEM characterization showed fine pores on the adsorbent surface. The highest adsorption efficiency obtained at FA-dolomite 2% was 97.364% and the lowest obtained at FA-dolomite 8% was 13.16% with a flow rate of 500 ml/h, adsorbent height of 9 cm and 3 trays. The greater the amount of dolomite added, the absorption efficiency decreases.

Efektivitas Pengapuran dalam Meningkatkan Pertumbuhan dan Produksi Tanaman Sorgum (Sorghum bicolor (L.) Moench) sebagai Hijauan Pakan Ternak


 Sorghum is a potential crop as feed forage. The objective of the research was to obtain optimum dose of liming to improve the growth and productivity of sorghum (Sorghum bicolor (L.) Moench) biomass as feed forage. A completely randomized design with 4 treatments and 4 replications were applied for the research. The treatments were doses of dolomite lime addition i.e., 1) SD0 (dolomite lime addition at a dose of 0 ton/ha) as a control, 2) SD1 (dolomite lime addition at a dose of 1 ton/ha), 3) SD2 (dolomite lime addition at a dose of 2 ton/ha), and 4) SD3 (dolomite lime addition at a dose of 3 ton/ha). The result shows that supplementation of dolomite lime at doses of 2‒3 tons ha-1 can increase soil pH after a week of incubation. The dolomite lime addition at a dose of 3 tons ha-1 significantly increases (P<0.05) the plant height (2 weeks after planting) and the number of leaves from a week after planting until the end of the research (10 weeks after planting). In addition, this dose of dolomite addition (3 tons/ha) can increase fresh biomass productivity as well as dry biomass compared to control (SD0). In conclusion, supplementation of dolomite lime at a dose of 3 tons ha-1 was effective to increase the pH value of soil, plant height, leaves number, as well as fresh and dry biomass of sorghum plant. In addition, this dose of dolomite lime produces better green color of sorghum plant leaf compared to without liming.
 
 Keywords: biomass production, dolomite lime, feed forage, Sorghum bicolor (L.) Moench

Effect of fresh bed materials on alkali release and thermogravimetric behavior during straw gasification

Alkali-associated problems are key issues for the efficient use of straw that is available as a major renewable energy resource worldwide. The effects of six bed materials commonly used in fluidized bed reactors on straw pyrolysis and char gasification were evaluated using online monitoring of alkali release and thermogravimetric analysis. Scanning electron microscopy with energy dispersive spectroscopy was used to determine the elemental composition of the char surface. In the straw pyrolysis stage, alkali release is reduced by the addition of dolomite and silica due to alkali adsorption on the bed materials, and enhanced by the addition of alumina because of its high sodium content. In the char gasification stage, silica, sea sand, olivine, and ilmenite reduce the char reactivity and alkali release, which is attributed to transfer of Si and Ti from the bed materials to the char and reaction with alkali to form stable and catalytically inactive compounds. Alumina also reduces the char conversion rate by transfer of Al to the char and formation of K-Al-Si and Ca-Al-Si compounds, while alkali release from the straw and alumina blend remains high due to the high Na content in alumina. Dolomite initially appears to increase the char gasification reactivity, but the results are affected by conversion of volatile matter that deposited on the dolomite in the straw pyrolysis stage. Dolomite also significantly increases the alkali release, which is attributed to Ca reactions with aluminosilicate compounds that allow potassium to remain in volatile form. Fresh bed materials are concluded to have significant effects on straw conversion depending on their chemical composition, and the results can contribute to the understanding required for efficient use of straw in commercial applications of biomass thermochemical conversion.

Sand modification with a saponite clay suspension as a waste of the diamond mining industry

The results of the laboratory water permeability tests of a sand modified by a saponite clay fraction from the diamond mining industry waste are presented. The filtration of clay suspension through a landfill ground bed as a method of the additive enrichment is approved. The experimental apparatus consisted of the triaxial test chambers and semi-automatic devices for water and suspension supplying. The chambers excluded a sidewall leakage in the samples and provided required values of the vertical and horizontal stresses when measuring permeability. The samples of an alluvial fine sand and a sand mixed with 3 and 5 % a chalk and a dolomite were investigated. After preliminary saturation the rate of distilled water flow through the samples were determined at four values of hydraulic gradient. Then the filtration of a suspension containing up to 0.58-0.63 % clay particles was conducted. After that, the pore disks at the top of samples were washed by circulating water flow. At the last step of experiments the velocity of water flow was measured again at four values of hydraulic gradient. The experiments indicated that the modification of the sand by clogging the pores by the saponite clay fraction from a suspension flow is possible if a sand comprises the additives causing the aggregation of clay particles. The hydraulic conductivity of a sand with 3 % chalk decreased by 15-31 times, with 5 % - by 15-39 times at different values of relative compaction. The effect of a dolomite addition was not significant, the hydraulic conductivity decreased by a maximum of 14.3 times. To achieve the maximum depth of clogging, it is recommended to filtrate the suspension through a loose sand at a hydraulic gradient that provides a flow rate more than 3.5 m/day, after that, the sand layer should be compacted.

Catalysis/CO2 sorption enhanced pyrolysis-gasification of biomass for H2-rich gas production: Effects of activated carbon, NiO active component and calcined dolomite

This study aims to reveal the effects of activated carbon (AC), NiO active component and calcined dolomite addition on the H2-rich gas production from pyrolysis-gasification of biomass, the experiments were conducted on a two-staged fixed-bed reactor with sawdust (SD) as biomass feedstock. It was found that the H2-rich gas production was largely enhanced by AC catalyst due to its catalytic effect on volatiles gasification as well as its self-gasification during the process. Lower impregnation ratio of ZnCl2 or H3PO4 to biomass was preferable to the H2 production. H3PO4 activation char (PAC) might keep more active structures with higher AC yields compared with ZnCl2 activation char (ZAC). NiO would mainly enter into the micropores of AC, possibly covered some of the active sites on AC surface, thus caused the decrease in AC self-gasification, although certain catalytic effect of NiO on H2 production was also observed. Additional calcined dolomite introduction together with NiO/AC catalyst could further increase the H2 concentration and yield. A remarkable synergistic strengthening effect was found between NiO/PAC-SD catalyst and calcined dolomite, the maximum H2 concentration and yield of 62.54 vol% and 1343.52 mL/g biomass were achieved with the addition of NiO/PAC-SD-1 and calcined dolomite due to the combination of in situ CO2 sorption enhancing effect and NiO/PAC-SD-1 catalytic effect as well as the enhanced AC self-gasification. It is thus illustrated that the catalysis/sorption enhanced pyrolysis-gasification of biomass using NiO/AC catalyst and calcined dolomite is an effective way to produce a H2-rich gas and shows a good prospect in the carbon-constrained future.

Improvement of growth and yield of organic broccoli (Brassica oleracea var. Italica) by application of different organic materials combination

Pot experiment was conducted to evaluate the effect of organic materials combination on improvement of growth and yield of organic broccoli. There were 19 treatments in total consisted of four types organic materials that were azolla (A), vermicompost (V), cow dung (S), and chicken manure (F) applied in combination, blank control, and inorganic fertilizer as comparison standard. The experiment results showed that application of organic materials combination significantly increased the growth of plant, diameter head and yield of broccoli compared with untreated soil and inorganic fertilizer treatment. The addition of dolomite into the organic materials combination tended to decrease the growth and yield of broccoli than no addition of dolomite. However, the addition of chicken manure into the combination showed higher growth and yield of broccoli. The best combination of organic materials in raising the growth and yield of broccoli was azolla, and chicken manure (A+F).

Effect of Dolomite Addition on the Structure and Properties of Multicomponent Amphibolite Glasses.

The structure and properties of the glass can be modified by introducing appropriate additives. Dolomite is one of the primary raw materials modifying the properties of glass, in which the essential component is calcium-magnesium double carbonate CaCO3∙MgCO3. The paper presents the research results on glasses obtained by smelting pure amphibolite and amphibolite modified with 10 and 20% dolomite additives. The raw material used was mined in the Poland region of Lower Silesia. The glass melting process was carried out in an electric furnace at 1450 °C for 2 h. The structure and properties of the glasses and crystallization products were determined by Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy—Energy Dispersive Spectroscopy (SEM-EDS). Viscosity and Vickers microhardness were also measured. It was found that the modification of amphibolite glass by adding dolomite affects the glasses’ properties and structure. The research results determined the effect of dolomite addition on the properties of alumino-silicate glasses in terms of the mineral fibre products used in the construction industry.

Intensification of the wastewater treatment process using magnesium-containing materials

An analysis was made of the use of magnesium-containing materials of natural and technogenic origin in complex systems for the purification of wastewater from mining enterprises from heavy metals. The transfer mechanisms of dissolved heavy metals into the precipitate and onto the surface of the sorbent have been theoretically studied. Magnesium-containing minerals in water partially undergo hydration, forming an association of complex molecules. The main purification mechanism is the formation of sparingly soluble metal hydroxides. The mechanisms of adsorption, co-precipitation, co-crystallization of impurities with products of hydration and hydrolysis of magnesium-containing minerals also work. Exploratory studies of the intensification of the wastewater treatment process using magnesium-containing materials have been carried out, which have shown that the residual concentration of almost all metals, with the exception of nickel and chromium, when using brucite at the same pH level is lower. The highest water purification efficiency is observed for zinc and lead ions. The addition of dolomite to brucite in an amount of less than 10% makes it possible to reduce the residual concentration of cadmium in water at 20-60 minutes of contact and other equal experimental conditions.

Properties of Boards Prepared from Mixture of Mineral Adducts with Bark and Cone of Calabrian Pine (Pinus brutia)

Olivine and dolomite addition with some formulations clearly retarded the water absorption change in both bark (Type 1 boards) and cone (Type 2 boards) based experimental panels. However, the lowest water absorption value of 15.20% was found in dolomite contain (40:60, dolomite-bark chip, w/w, %) sample which show approximately 169.6% lower than olivine contain sample at similar proportions. However, it is important to note that Type 1 boards show considerably lower water absorption than Type 2 boards at similar experimental conditions. The boards which produced with 10-, 20-, and 30% dolomite and 90-, 80-, 70% bark chips (XBI, XBII and XBIII) proportions, show higher thickness swelling (TS, %) than control (B0) while rest of show lower TS than control samples, regardless of type of mineral or experimental conditions. The highest TS improvement of -79.1% was found with sample of YBV which produced with equally (1:1, w/w) proportions olivine and pine cone chips in matrix. It is noticeable that dolomite addition to Type 1 boards are usually effects higher IB values than olivine added samples while the highest IB value of 0.72 MPa was found with sample of XBV. Moreover, only sample of XBII (20% dolomite and 80% pine bark chip in boards proportions, w/w) show higher MOR strength value (4.42 MPa) than control (B0: 3.63 MPa), regardless of mineral content. In Type 2 boards, all experimental panels that prepared with two different mineral addition at five loading levels show lower MOR values than control (C0: 6.59 Mpa). It is also realized that both Type 1 and 2 type experimental panels show lower elastic property (MOE) than control samples (B0: 1129.3 MPa: C0: 820.1).

Effect of dietary supplementation or cessation of magnesium-based alkalizers on milk fat output in dairy cows under milk fat depression conditions

We aimed to evaluate the effects of dietary supplementation with magnesium oxide and calcium-magnesium dolomite on milk fat synthesis and milk fatty acid profile or persistency in milk fat synthesis after their cessation in dairy cows under milk fat depression conditions. Twenty-four multiparous dairy cows in early lactation (mean ± standard deviation; 112 ± 14 d in milk) were used in a randomized complete block design. Milk fat depression was induced in all cows for 10 d by feeding a diet containing 35.2% starch, 28.7% neutral detergent fiber, and 4.8% total fatty acid (dry matter). The experiment was conducted in 2 periods. During the Mg-supplementation period (d 1-20), cows were randomly assigned to (1) the milk fat depression diet used during the induction phase (control; n = 8), (2) the control diet plus 0.4% magnesium oxide (MG; n = 8), or (3) the control diet plus 0.8% calcium-magnesium dolomite (CMC; n = 8). Compared with the control group, feeding the magnesium-supplemented diets increased milk fat concentration and yield by 12% within 4 d. During the 20-d Mg-supplementation period, both the MG and CMC diets increased milk fat concentration and yield, as well as 3.5% fat-corrected milk and energy-corrected milk yield, without affecting dry matter intake, milk yield, and milk protein and lactose concentrations. In the Mg-cessation period (d 21-30), all cows received the control diet, which resulted in a greater milk fat concentration and yield in the cows that had already received the MG and CMC diets in the Mg-supplementation period. Whereas, milk fat concentration and yield remained high after discontinuation of the magnesium-containing alkalizer until d 27. The difference in milk fat synthesis was associated with lower trans-10 C18:1 (-22%) and higher trans-11 C18:1 (+12.5%) concentrations in milk during the Mg-supplementation period. Furthermore, it was evident that within 2 d of supplementation, the trans-10:trans-11 ratio was lower in MG and CMC cows compared with cows receiving the control. This suggested that the effect of magnesium-based alkalizers on milk fat synthesis was mediated via a shift in ruminal biohydrogenation of cis-9,cis-12 C18:2 in the rumen. In conclusion, abrupt addition of magnesium oxide and calcium-magnesium dolomite increased milk fat synthesis, which persisted for 7 d after cessation of magnesium-based alkalizers. A similar ability to recover milk fat synthesis and normal fatty acid biohydrogenation pathways was observed for magnesium oxide and calcium-magnesium dolomite.

Effect of Dolomite Addition on Fly Ash Based Ceramic Membrane to Reduce COD and BOD of Liquid Waste

Ceramic membrane technology plays an essential role in separation fields such as wastewater treatment. Fly ash as a membrane material has proven to be very effective for many separation processes, including water and air purification, as well as industrial and environmental resource recovery. This study aims to develop a microfiltration ceramic membrane based on fly ash with the addition of dolomite. The synthesized ceramic membranes were then characterized using XRD, SEM, and TGA. Ceramic membranes are used to reduce COD and BOD levels in tofu industrial wastewater. The results showed that the value of membrane porosity tends to increase with the addition of dolomite 0% (D0) to 30% (D30). The increase in the porosity value in the membrane was followed by a decrease in the average pore size, namely 1.6994 m at D0 and 1.1730 m at D30. The membrane with 30% dolomite composition has the best mechanical properties with a compressive strength of 35.29 MPa and superior thermal resistance. This is very beneficial for the use of membranes in the long term. Meanwhile, the membrane filtration ability and the ability of the membrane to reduce COD and BOD levels of waste increased with the addition of dolomite from 0% to 30%. However, the decrease in COD and BOD was smaller in the membrane with 45% dolomite. D30 membrane can reduce COD 80% and BOD up to 71.44%. D30 membrane is the most effective fly ash and dolomite composition in forming pores on the membrane with the best COD and BOD reduction performance.