Reducing Silica Levels in WTP PLTGU X Wastewater using Rice Husk Filter Membranes

This study aims to study how the effect of adding rice husk additives to the characteristics of ceramic membranes with various variations of membrane-forming component composition in terms of surface morphology and pore size of the membrane produced. This research is expected to be used by the community as an alternative treatment of river water into clean water. In this study, the variables studied were the composition of the membrane constituent namely clay, iron powder and rice husk as an additives. The ceramic membrane was designed in the form of a tube, made from a mixture of clay, iron powder and rice husk with a diameter of 5 cm, an outer diameter of 6 cm, a thickness of 1 cm and a length of 25 cm. Housing membrane was made of glass fiber with an outer diameter of 9 cm, an inner diameter of 8.5 cm and a length of 30 cm. Making ceramic membranes were from clay, iron powder and rice husk with a ratio of 87.5%, 2.5%, 10%, 77.5%, 2.5%, 20% and 77.5%, 2.5%, 15%. The river water was treated by flowing to the complete separation process. It was taken every 15 minutes, 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes. Every sampling, the permeate volume was determined. Permeat events were analyzed for chemical parameters in the form of iron (Fe), Manganese (Mn) and Zinc (Zn). Based on the SEM-EDS analysis on the ceramic membrane produced shows that the membrane was classified in the microfiltration membrane group with a random and asymmetrical pore size and structure. According to the BET analysis on ceramic membranes shows that the best ceramic membrane produced in this study is C ceramic membrane with a clay composition of 87.5%; 10% of rice husk; and 2.5% of iron powder with a pore size of 2.8 μm and a large surface area of ​​45.38 m2/g. The difference in pressure of 2 bars gives the best results in reducing levels of contaminant compounds contained in river water with a percentage of Fe reduction of 92.18%, Mn of 89.23%, and Zn of 99.80%.

Rapid development leads to a high demand and increased price for the basic construction materials like cement. This led the researchers to look for possible partial cement replacement by investigating the potential use of rice husk in making concrete hollow blocks. The researchers created concrete hollow blocks (CHB) at three different percentage of rice husk (RH) powder addition from 0%, 5%, and 10%. This study was intended to evaluate which works best in terms of compressive strength and density. The researchers created a total of 36 samples but only 12 were tested at ASTEC Materials Testing Corporation. Cost analysis, compression testing, and measuring of dimensions are the methods used to gather data. Results from the testing show that the mean compressive strength of the normal CHB (0%) is 76 psi compared to only 53 psi and 39 psi for CHB with 5% and 10% RH, respectively. The density of the normal CHB is 1.4319 g/cm3 while 1.2497 g/cm3 and 1.2822g/cm3 for CHB with 5% and 10% RH, respectively. In the cost analysis, the normal CHB costs ₱11.58 per piece, for CHB with 5% RH is ₱11.48, and for CHB with 10% RH is ₱11.37. Since the compressive strength of the normal CHB is greater than that of the CHB with pulverized rice husk, the researchers have concluded that a CHB unit is stronger and more resilient than a CHB with pulverized rice husk. Likewise, the mean density of the normal CHB is also greater than that of CHB with rice husk powder, it can be established that a CHB unit is more compact and rigid than the alternative. However, the addition of rice husk powder decreases the cost of CHB, therefore, CHB with RH is a more economical building material.

The usage of solid waste materials in the production of construction materials has received considerable attention across the world. Various types of bricks are used in construction. The most common are conventional bricks. Owing to the exploitation of large amount of natural resources in the manufacturing of conventional bricks, we provide an alternative solution for conventional bricks through this project. The present study investigates the feasibility of using rice husk powder, cow dung and egg shell powder in the manufacturing of fly ash bricks. Fly ash bricks of different compositions with rice husk, cow dung and egg shell powder were prepared in steel moulds. After casting, the brick samples were stored at 35 C and a relative humidity of 50% until the ages required for testing. The brick samples were checked for dimensions and visible defects. The effects of rice husk, cow dung and egg shell powder contents on the engineering properties of the solid bricks were also investigated. The test results showed that all brick samples exhibited good compressive strength. The compression strength ranged between. It is concluded that the manufactured bricks acquired sufficient strength and became more economical.

In order to preserve the natural fine aggregates and proper waste resources recycling, rice husk and eggshell powders were used as filler materials in production of standard M30 grade mortar. Natural fine aggregate was replaced with rice husk powder (RHP) at 3%, 5%, 7%, 10%, 12%, and 15%, and with eggshell powder (EP) at 3%, 5%, and 7%, both at a constant water-to-cement ratio of 0.40. Compressive strength, split tensile strength, water absorption, pore distribution, and electrical resistivity of the mortar samples were investigated. Also, XRD, SEM, and EDS were performed to observe the samples’ chemical phases and microstructure. The results show that up to 15% RHP reduced the compressive strength by 20–35%, whereas the up to 7% EP obtained a similar (varies by 0–5%) result compared to the control sample at 28 days. Furthermore, the results suggest that sand replacement with RHP and EP had no impact on the water absorption and pore volume of mortars. Also, the samples made with up to 15% RHP and 7% EP improved the resistivity by up to 80% and 15%, respectively, providing better resistance to chloride ion migration. Based on the results, it is recommended to use the RHP and EP up to a level of 5% and 7%, respectively, in sustainable M30 grade mortar production.

Electron-beam-irradiated rice husk powder as reinforcing filler in natural rubber/high-density polyethylene (NR/HDPE) composites

This research examines the mechanical, morphological, and moisture assimilation of composite materials built up from sugarcane bagasse fiber (SBF), rice husk (RH), and wood powder (WP) filler. Regular threads are now regarded as eco-friendly materials because of their sustainability. This article’s goal is to choose between two polymer structures with fiber and matrix: case 1 has epoxy (50%) plus sugarcane bagasse fiber (30%–45%) and wooden powder (5%–20%); case 2 has epoxy (50%) plus sugarcane fiber (30%–45%) plus rice husk (5%–20%). The impact of the mechanical test is compared to obtaining the best fiber volume fraction (Vf), and the failure of cracked surfaces and interfacial bonding analysis is done using SEM as a consequence of matrix cracking, void content, and fiber pullout. In order to get the characterization of materials, Thermo-Gravimetric Analysis (TGA) and X-Ray Diffraction (XRD) analyses were also performed. However, Sugarcane Bagasse Fiber, a single fiber, combined with an epoxy composite matrix demonstrated a strength of 14 to 18 Mpa and 230 to 250 g of weight. Nevertheless, when SBF was combined with hybrid materials like Rice Husk and Wood Powder, it demonstrated superior strength, with an estimate of 16 to 20 Mpa and a weight of 220 to 240 g.

This study was carried out to investigate the comparative toxicity of seeds of Piper guineense Schum & Thonn, Capsicum annum L., diatomaceous earth, pirimiphos-methyl dust, rice husk (powder and ash) against Callosobruchus maculatus (F.) in stored cowpea seeds. Toxicity test was carried out by exposing five pairs each of freshly emerged beetles to the substrate materials at the rates of 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 g/20 g of grains. The experiment conducted at ambient temperature of 28 °C ± 2 °C and 75% ± 5% relative humidity was replicated three times and arranged in a completely randomized design. Adult mortality was observed for four days. The following phytochemicals were observed in the materials: alkaloids, saponins, tannin, flavonoid and glycosides. Results of the toxicity assay revealed that rice husk ash was the most toxic to adult C. maculatus with 100% mortality (p ≤ 0.05) within 72 h of exposure at a concentration of 0.1 g/20 g grains. Pirimiphos methyl gave a significantly high mortality of 76.67% at a concentration of 0.2 g/20 g of grains in cowpea after 72 h of application. The least efficacy was observed with rice husk powder evoking 3.33% at a dosage of 0.3 g/20 g in cowpea. The treated grains significantly reduced the oviposition and adult emergence of C. maculatus and were significantly different from the control in all the different dosages. Oviposition and adult emergence were lowest in rice husk ash with 8 eggs and 24.62% adult emergence in C. maculatus, at 0.5 g/20 g dosage. The percentage adult emergence in the untreated grains was significantly different (higher) (p ˃ 0.05) from the emergence in the treated cowpea grains across the dosages. At all levels of dosages, the powders and ash significantly reduced weight loss, damage and weevil perforation index caused by the beetle. Rice husk ash at 0.5 g dosage recorded the lowest weight loss, grain damage and weevil perforation index of 0.40%, 1.95% and 5.80%, respectively. The findings from this research showed that rice husk ash was most potent/toxic to C. maculatus and its use could be encouraged especially in small scale storage.

Recent strategies for enhancing the performance and lifespan of low-cost ceramic membranes in water filtration and treatment processes: A review

Fabrication of low cost, green silica based ceramic hollow fibre membrane prepared from waste rice husk for water filtration application

Rice is an essential plant that brings high economic value to Viet Nam. In addition to the main product, rice agriculture produces a significant amount of by-products each year. This waste is known as rice husk. The amount of rice husks discharged each year is estimated to be over 9 million tons. They are usually processed by burning. Another amount is released into the environment. These treatments are potentially harmful to the environment and bring low economic efficiency. Therefore, many ways of treatment were suggested and considered. In this study, rice husk was used to synthesize phenolic resin. The rice husk was ground to powder less than 500μm. The husk powder, phenol, and sulfuric acid were mixed with different ratios. The mixtures were heated to 150℃ and soaked for 180 minutes. The efficiency of the reaction was evaluated through the remaining amount of rice husk. The C13 Nuclear Magnetic Resonance Spectroscopy (C13 - NMR) and Fourier Transform Infrared Spectroscopy (FTIR) were used to determine the structure and functional groups of the resin. A number average molecular weight (Mn) and a weight average molecular weight (Mw) were defined by using Gel Permeation Chromatography (GPC). The results show that phenolic resin was synthesized successfully from rice husk. The optimal ratio between phenol and rice husk powder is 2:1 with a 5% sulfuric acid additive. The efficiency of the reaction is determined at 90.34%. The results of structure prediction by FTIR and C13 - NMR show that the molecular formula of the formed resin is (CH2 - C6H4 - OH)n. It has the weight average molecular weight value of 11709 and the number average molecular weight of 7782. The synthesized phenolic resin can be applied as a binder or as one kind of heat-resistant plastic.

The current available wood-plastic materials used for selective laser sintering (SLS) investment casting are often poor in fluidity in molten state, which is not easy to flow out the shell mold. This led to a large amount of residual ash in mold after heating and lowered the quality of the sintered parts. In this article, the Co-Polyamide (Co-PA Hotmelt adhesive) and rice husk powders (RH) were proposed as the feedstock of the rice husk (RH)/CO-PA composite (RHPA) for SLS. CO-PA with good fluidity was used as the matrix and RH powder as the additive materials. This paper aims to optimize the SLS processing parameters and determine the optimal ratio of RHPA parts manufactured by SLS. Through this work, an orthogonal experimental method of five factors and four levels was used to determine the optimum SLS parameters for the RHPA SLS test. The scan spacing, scan speed, laser power, layer thickness, and preheating temperature are chosen as main SLS affecting factors of this study. The synthesis weighted scoring methods were used to conclude the optimal combination of SLS parameters of RHPA i.e., scan spacing = 0.15mm, scan speed = 2m/s, laser power =16W, layer thickness = 0.25 mm and the preheating temperature = 74°C. Moreover, the influence of RH content on the mechanical properties, dimensional accuracy, and the residual ash content of RHPA parts was determined. When the ratio of RH powder on RHPA is 10 wt %, the bending strength of the sintered parts will reach 2 MPa. Besides, the residual ash content of RHPA parts after heating step was lower (1.1881%) and the tolerance level is CT5. Thus, the dimensional accuracy in X, Y, and Z directions of 10 wt % RHPA SLS parts is 99.79%, 98.71%, and 97.9%, respectively; and the surface of casting was smooth and clear details.

Silicon carbide (SiC) is a mineral with good technical properties and high economic value. However, the synthesis of SiC is expensive because it is synthesized at a high-temperature environment (above 1500oC). The synthesis of SiC from biomass can significantly reduce the synthesis temperature. One commonly used biomass material for synthesizing SiC is rice husk. However, the ability to synthesize SiC depends on the shape of the rice husk. The influence of the morphology of rice husk on the ability to synthesize SiC was studied in this study. Experimental results showed that the original rice husk would give better SiC formation capacity than the rice husk powder. The amount of SiC formed using the original rice husk when impregnated by sodium silicate solution and pyrolysis at 1200oC is 18.3% (wt%.). With rice husk powder, it is 15.12% (wt%.). The results of analysis of the mineral composition, functional groups, and morphologies by X-ray diffraction (XRD), Fourier Infrared Transform Method (FT-IR), and Scanning Electron Microscopy (SEM) found that the polymorphy of SiC is α-SiC and β-SiC. These minerals are the basis for SiC from rice husks, which can be applied as wear-resistant materials.

Rice husk (RH) has high content of silica. In this study, the extraction of silica from rice husk while maintaining the organics was carried out by warm water pre-treatment followed by alkaline hydrolysis. RH powder was treated with water at 50oC and 100oC prior to treatment with 1 M of sodium hydroxide (NaOH) aqueous solution at 50oC. The filtrate from the alkaline hydrolysis was then further reacted with 1 M of hydrochloric acid (HCl) for silica extraction. The samples obtained after each stage of the treatments were carefully characterized and their chemical compositions were determined. The morphology of the untreated and treated RH powder was analyzed by Scanning Electron Microscopy (SEM). Estimation on the silica content was made by Energy Dispersive X-ray (EDX). The functional group present in untreated and treated RH were determined by Fourier Transform Infrared Spectroscopy (FTIR). The percentage of silica extracted from ΔH2O/NaOH-RH filtrate was higher (18.9%) than from H2O/NaOH-RH filtrate (12.6%). FTIR spectroscopy data indicated the disappearance of siloxane group when RH was treated with hot water and warm water followed by alkaline hydrolysis. The selected extraction method has successfully recovered silica at high yield but at the same time maintaining the organic compounds in the rice husk.

Chromium is released into water bodies through metallurgical operations, metal finishing, steel alloy and chrome plating. Various techniques for removal of hexavalent chromium from aqueous medium such as ion exchange, coagulation, membrane filtration, electro dialysis are available. The mutagenic and carcinogenic properties of hexavalent Chromium required the need of remedial measures using rice husk and maize stem powder to avoid high cost involved in traditional methods. Agriculture bye products and wastes have been exploited for remediation of Cr (VI) in order to know the feasibility of biosorption. Carboxylic acid group, hydroxyl group, lignin and carbohydrate present in rice husk and maize stem increase the adsorption potential for Cr (VI). 2 ppm initial concentration of Cr (VI) is treated with 1 gm rice husk up to 1 hour, 2 hours and 3 hours and 2 gm and 3 gm rice husk up to 1 hour decreased the concentration up to a minimum of 0.13 ppm while in case of maize stem powder the equilibrium concentration was 0.247 ppm at pH 7.00. A Langmuir adsorption isotherm has been tested from available data. Adsorptive removal of Cr (VI) follows first order kinetics.

Large quantities of produced water are generated in oil and gas fields all over the world: the production of one barrel of crude oil generates three barrels of produced water and the water/oil ratio increases drastically over the life of the fields. It is a by-product of petroleum production and needs to be managed efficiently. Produced Water Re-Injection (PWRI) is frequently the selected option over the disposal option for environmental considerations. However due to the combined presence of suspended solids and oil-in-water emulsion, the efficiency of topside filtration and therefore the well injectivity is often problematic. Membrane filtration is considered as a very attractive treatment process that may allow PWRI even in difficult reservoirs without loss of injectivity. An industrial-scale water treatment pilot has been installed in an oil terminal to test the performance of ceramic ultrafiltration membranes. The purposes of the tests were to evaluate the performance of various types of membranes in terms of material, pore size and geometry, the impact of chemical additives and to establish effective cleaning procedures. Nine months of tests allowed TOTAL and VEOLIA Water to determine the parameters required for the design of an industrial full field ceramic ultrafiltration membrane unit. The ultrafiltered produced water was also used to feed a dedicated core pilot to test the injectivity of this treated water into different types of reservoir rocks. This paper presents the results of these two pilots; it provides new information for the Exploration and Production (E&P) industry on the key parameters to design a ceramic ultrafiltration membrane system for produced water, the main operational constraints and the sustainability of the injectivity. Introduction To increase the recovery rate of oil reserves, water injection is usually used during oil production. If most of the injected water comes from sea water treatment, Production Water Re-Injection (PWRI) may be implemented. To optimize production water treatment for re-injection and to reduce oil content in rejected effluents, an offshore compatible technology is needed. As a modular, compact and economical solution, ceramic membrane filtration was tested on site (oil field terminal) as a package in a collaboration between Total and VEOLIA Water. Figure 1 below shows some pictures of the ceramic membrane pilot installed in a container.