Chemical characterization methods for biodegradable organic wastes with relevance for the composting process. Case study

The study aimed to develop some methods for the compositional characterization of biodegradable waste with relevance to the composting process at the laboratory level. For testing, four waste fractions were selected, such as waste-based on dehydrated sludge, waste from parks (leaves, branches), market waste (mixture of vegetable and fruit), and cardboard waste. For metals and phosphorus, several microwave digestion methods were applied. The ammonium nitrogen content (NH4-N) was determined using a number of extraction procedures (water, CaCl2, and KCl). Three certified reference materials were used for testing the validity of the results. Recovery percentages higher than 90% were obtained. The developed and validated methods are suitable for biodegradable waste characterization used in composting processes.

Properties of concrete containing microwaved sewage sludge ash

Urban population of Malaysia is stated as 72.8% of its total population, and growing every year. Due to this growing number of population, the sewage sludge waste produce every year has also gradually increased. Malaysia itself produces 3.2 million m3 of sewage sludge annually. Normally all of this waste is disposed by landfill. Furthermore, usual production of cement and sewage sludge ash consumes a lot of energy by using incineration process with a very high temperature. Thus, microwave heating method was an alternatives use in this research to reduce the consumption of energy and time used to heat the sewage sludge ash. This research was conducted to investigate the optimum performances of different percentage (0%, 5%, 10%, 15% and 20%) by weight of cement of the Microwaved Sewage Sludge Ash (MSSA) concrete with different curing regime, which was air and water curing. The characteristic of MSSA was tested by X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The mechanical properties of MSSA concrete was examined by Compressive Strength test, Flexural Strength test and Modulus of Elasticity test after 180 days of curing. The MSSA samples were also tested with water absorption test to evaluate the quality of concrete in term of porosity and permeability. Water curing sample with 5% of MSSA (W5) had the best in results compared to other specimens. The mechanical properties of W5 content in concrete shows the most optimum samples due to the densification of pozzolanic reaction and filler effect of MSSA. The curing effect with better result was water curing, as it got highest value of strength in compressive test, flexural test and modulus of elasticity test. As conclusion, based on the results, it is shown the positive impact on using the MSSA as additional material to the cement mixture to improve the quality of the concrete. Thus, this will reduce the disposal of sewage sludge waste on dumping site and improves the quality performances of the concrete.

Magnesite Ore Washing Facilities’ Wastewater Treatment and Recovered Water Reuse

Grecian Magnesite S.A., located in Gerakini, Chalkidiki, N. Greece, is a magnesite mining company, which produces and commercializes several Mg-based products. For production purposes, water is applied in large quantities for several uses. As a result, 5 × 106–7 × 106 m3 of wastewater, consisting mainly of muddy water, is produced from the magnesite ore washing facilities each year. In this study, the environmental impact of mining and industrial activities is examined, and the water management issues are addressed through its recovery. Water recovery reaches up to 96% (v/v), whereas the remaining sludge waste is safely deposited in tailings ponds.

Reducing Environment Pollution by Reusing of Alum Sludge Waste in Stone Mastic Asphalt Mixtures

Globally, a huge quantity of alum sludge waste is produced as a by-product material from drinking water treatment plants that utilize aluminum salts as an essential coagulate and is the most generally produced water treatment remaining sludge around the world, which causes a serious environmental problem. Direct discarding of this substance has ecological effects. Hence, it is important to reuse this alum sludge waste material in such a manner to diminish its detrimental impacts on the environment. This research investigates the possibility of reusing alum sludge waste as a partial replacement of cement filler in stone mastic asphalt (SMA) paving mixtures. For this investigation, the alum sludge was used as a filler material in SMA mixtures in two modes; dried alum sludge at 110°C and burned alum sludge at 700°C. Different percentages of alum sludge were used as a replacement by the total weight of mineral filler at 0, 20, 40, 60, 80, and 100%. The results showed that using alum sludge as a substitution of filler in SMA mixtures reduces the performance of the mixtures in terms of Marshall properties and tensile strength for both dried and burned alum sludge compared with a standard mix. However, the performance of the mixtures containing burned alum sludge gave a better performance than the mixtures containing dried alum sludge.

Physical and Mechanical Properties of Non-Stoichiometric Cordierite with Treated FGD Sludge Addition Sintered at 1250°C

The effects of addition treated FGD sludge in non-stoichiometric cordierite, by benefiting from its high mechanical strength and good thermal performance, can hold promise for more practical applications of non-stoichiometric cordierite. Treated FGD sludge waste from borosilicate glass industrial were used as a flux to reduce the sintering temperature of cordierite. Cordierite ceramics were prepared using silica (SiO2), alumina (Al2O3), talc, kaolin, magnesia (MgO) and treated FGD sludge via solid-state reaction method. The cordierite were prepared by adjusting the ratio of FGD sludge and magnesia in the cordierite composition, respectively. 4 composition of cordierite with 0%, 1.5%, 3.0% and 4.5% of FGD sludge were prepared to obtain the formation of α-cordierite that can be determine by X-ray diffraction (XRD) analysis. Porosity, density, shrinkage and flexural strength for each of cordierite composition were determined to obtain the best composition of treated FGD sludge required for sintering aids of cordierite. Only FGD 3.0% able to synthesis pure α-cordierite while FGD 1.5 % shows an improvement in both porosity and density. The increasing amount of treated FGD sludge lead to decreasing in mechanical strength of cordierite ceramic due to porous formation.

Phase Transformation and Microstructure Characterization of Ceramic Porcelain with Different Ratio of Treated Fgd Sludge/Feldspar

The porcelain formulation containing percentages of treated FGD sludge waste from 5% up to 15% in replacement of feldspar were prepared. The porcelain mixture formulation were mixed by high energy planatery mill at speed 300 rpm for 1 hours. The powder were compacted by using hydraulic press and sintered at temperature 1200 °C for 3 hours. The sintered samples were characterized using X-ray fluorescene (XRF), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and Thermogravimetry/Differential scanning calorimetry (TGA/DCS). The primary effect concerning the addition of treated FGD sludge was the change of intensity composition (gypsum and anhydrate) in porcelain formulation. The XRD analysis has shown that the main component in sludge waste were gypsum and anhydrate.

Investigation of the possibilities of dewatering sewage sludge by the method of electroosmosis in order to prevent land littering

Wastewater sludge from industrial enterprises is disposed of at disposal sites. This leads to a negative impact on the soil cover. The well-known methods of dehydration of moisture-containing materials have been studied. The chemical composition of sewage sludge was investigated. A technical solution for reducing the volume of wastewater sludge formation is considered on the example of cardboard and paper production. An electroosmotic installation is proposed. To study the process of sludge dewatering, a series of experiments was carried out on the installation with variable parameters of the voltage between the electrodes. A model of the particle velocity in the medium under study was presented. It has been proven that with the help of an electroosmotic device, up to 70% of moisture is effectively removed from the volume of waste sludge waste. This makes it possible to significantly reduce their volumes, reduce areas for possible or temporary placement and reduce the environmental load on the environment.

Characterisation Of FGD Sludge From One of Glass Industrial in Malaysia and Their Potential as Ceramic Mould

Flue Gas Desulfurization (FGD) is a waste incineration process used to eliminate sulfur dioxide (SO2) from flue gas power plants. Limestone/gypsum was injected into the plant to trap sulfur dioxide and change their chemical composition from calcium carbonate to calcium sulfate dehydrate, known as FGD sludge wet scrubber. Nowadays, it is necessary to overcome the environmental pollution caused by the massive production of FGD sludge waste through recycling. In this research, FGD sludge was characterised to reveal its chemical composition, crystalline phase, and FTIR spectra characteristics. FGD sludge recorded a moderate alkaline with a pH of 8.24. Based on the XRD result, FGD sludge was mainly composed of gypsum (CaSO4•2H2O) and anhydrite (CaSO4). XRF analysis also shows that FGD sludge was mainly composed of calcium oxide, sulfur trioxide, silica, and potassium oxide.

Study the Structure Characterization of Porcelain Formulation at Different Sludge Content

Porcelain formulation in the form of pellets have been studied by substituted fluxing materials with treated FGD sludge at different percentages. In this work, treated FGD sludge was added in percentages from 5% up to 15% uniaxially pressed at 11 MPa, dried and then sintered at temperature 1200 °C for 3 hours. Weight loss, volume shrinkage/expand, bulk density, densification, porosity and flexural strength were investigated on sintered samples. This demonstrated that the treated FGD sludge addition in porcelain formulation has influenced on the sintered samples. It was concluded that the treated FGD sludge waste could be used as a suitable raw material source for production of porous porcelain ceramic due to their organic and inorganic content.