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

2021 ◽  
Vol 9 (2) ◽  
pp. 76-82
Author(s):  
Omar T. Mahmood

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.

2012 ◽  
Vol 6 (5) ◽  
pp. 184-197
Author(s):  
Ooi Chong Hoe ◽  
Siti Rozaimah Sheikh Abdullah ◽  
Noorhisham Tan Kofli ◽  
Mushrifah Idris

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Mohammad Saeed Pourtahmasb ◽  
Mohamed Rehan Karim

Recycled concrete aggregate (RCA) is considered as one of the largest wastes in the entire world which is produced by demolishing concrete structures such as buildings, bridges, and dams. It is the intention of scientists and researchers, as well as people in authority, to explore waste material recycling for environmental and economic advantages. The current paper presents an experimental research on the feasibility of reusing RCA in stone mastic asphalt (SMA) mixtures as a partial replacement of coarse and fine aggregates. The engineering properties of SMA mixtures containing RCA have been evaluated for different percentages of binders based on the Marshall mix design method. The outcomes were statistically analyzed using two-factor analysis of variance (ANOVA). Test results revealed that the performance of SMA mixtures is affected by RCA due to higher porosity and absorption of RCA in comparison with virgin granite aggregates. However, the engineering properties of SMA mixtures containing a particular amount of RCA showed the acceptable trends and could satisfy the standard requirements. Moreover, to achieve desirable performance characteristics, more caution should be made on properties of SMA mixtures containing RCA.


2016 ◽  
Vol 701 ◽  
pp. 138-142 ◽  
Author(s):  
Mohamat Yusuff Soleha ◽  
Keat Khim Ong ◽  
Wan Yunus Wan Md Zin ◽  
Ahmad Mansor ◽  
Fitrianto Anwar ◽  
...  

Use of alum as a coagulant in drinking water treatment process generates an alum sludge as a waste product. Since the amount of this sludge is huge, it is crucial for a water work management to properly handle and dispose of this sludge. Reuse of this alum sludge as a solid adsorbent is one of the proposed applications for this material but modification and characterization are needed to alter and identify its properties so that optimum benefits are obtained. This paper reports characterization of raw and thermally treated alum sludge. The raw alum sludge was collected from a local water treatment plant and heated at 300 °C and 800 °C for 7 hours using a furnace before characterization using scanning electron microscopy energy (SEM), thermogravimetric (TGA), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The results showed that surface morphology, thermal properties, microstructure, surface area and porosity of the sludge were affected by heating temperature whereby increase the heating temperature resulted in improved thermal stability of the sludge. The results also revealed that both raw and thermally treated alum sludge were mesoporous materials and mainly compose of quartz and kaolinite. It can be said that the sludge could be a good candidate as low cost adsorbent.


2021 ◽  
Vol 3 (2) ◽  
pp. 114-119
Author(s):  
Adina Pacala ◽  
◽  
Maria Laura Samonid ◽  
Bogdan Murariu ◽  

Aluminum salts are widely used across Romania in surface water treatment as coagulants. It is well-known that the efficiency of these coagulants has a complex dependency on the nature of the raw water, being affected by temperature, pH, and suspended solids. The objective of this case study was to compare the coagulation-flocculation efficiency process of raw water from the Bega River, at low temperature and turbidity, taking into account the use of alternative coagulating agents such as alum, poly aluminum chloride (PAC), and their mixing in 1:1 ratio. The raw water samples were treated using the "Jar Test" procedure, comparable with the current plant conditions at Timisoara Waterworks and taking into account possible operational improvements. For the mixture method applied in which was combined alum and PAC in 1:1 mixing ratio were achieved lower concentrations in aluminum residual, TOC, and turbidity.


2019 ◽  
Author(s):  
Wenfa Ng

Quality of produced water is usually the criterion for selecting between different desalination technologies for turning seawater into drinking water. However, contemporary trend in drinking water treatment sees a convergence between different technologies for the same water quality. Hence, how do different desalination technologies differentiate amongst each other? Awareness of climate change impact as well as price of produced water, energy use per unit of treated water is an oft-used criterion for assessing the effectiveness and efficiency of different desalination technologies. Specifically, comparing multi-effect flash evaporation and reverse osmosis, the latter enjoys a significant energy use advantage given the lack of the need for converting water into the vapor phase as in multi-effect flash evaporation. Thus, energy used in producing drinking water is significantly higher in multi-effect flash evaporation compared to the high pressure process of reverse osmosis. From the operation perspective, reverse osmosis also benefits from its ability to scale linearly in increasing water production capacity through addition of extra membrane modules, which is not the case for multi-effect flash evaporation where a new distillation column is required for significant increase in production capacity. Collectively, with the same quality of water produced by different desalination technologies, comparison between different technologies increasingly relies on the energy use per unit of produced water. Using this criterion, reverse osmosis membrane desalination has a significant advantage relative to multi-effect flash evaporation in energy cost, which translates to a lower price of produced water.


2012 ◽  
Vol 1380 ◽  
Author(s):  
F. Espejel-Ayala ◽  
R. M. Ramírez Z.

ABSTRACTThe present work describes a patent applied for registration at the IMPI (Instituto Mexicano de la Propiedad Industrial) of a production process of zeolite X using as raw materials alum sludges issued from drinking water treatment plants. Sludge sample was collected in a water drinking plant located northern Mexico City. The sample was dried and then physicochemical and microbiological analyses were carried out (metal content, main oxides content, mineralogical analysis, helminth eggs content, fecal coliforms). In accordance with its characterization, two main steps of the zeolites production process were performed: 1) alkaline fusion of alum sludge-NaOH mixture for increasing the dissolved precursor’s content and 2) alkaline hydrothermal treatment. Spherical particles of zeolite X were identified by SEM and XRD respectively. The best synthesized zeolite showed a CEC=2.11 meq/g, value being similar to the data reported for clinoptilolite (the most commonly zeolite used for water treatment in the removal of heavy metals). Thus, the synthesized zeolite X in this work can be used for the same purpose.


2019 ◽  
Author(s):  
Wenfa Ng

Quality of produced water is usually the criterion for selecting between different desalination technologies for turning seawater into drinking water. However, contemporary trend in drinking water treatment sees a convergence between different technologies for the same water quality. Hence, how do different desalination technologies differentiate amongst each other? Awareness of climate change impact as well as price of produced water, energy use per unit of treated water is an oft-used criterion for assessing the effectiveness and efficiency of different desalination technologies. Specifically, comparing multi-effect flash evaporation and reverse osmosis, the latter enjoys a significant energy use advantage given the lack of the need for converting water into the vapor phase as in multi-effect flash evaporation. Thus, energy used in producing drinking water is significantly higher in multi-effect flash evaporation compared to the high pressure process of reverse osmosis. From the operation perspective, reverse osmosis also benefits from its ability to scale linearly in increasing water production capacity through addition of extra membrane modules, which is not the case for multi-effect flash evaporation where a new distillation column is required for significant increase in production capacity. Collectively, with the same quality of water produced by different desalination technologies, comparison between different technologies increasingly relies on the energy use per unit of produced water. Using this criterion, reverse osmosis membrane desalination has a significant advantage relative to multi-effect flash evaporation in energy cost, which translates to a lower price of produced water.


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