scholarly journals Compost leachate treatment using polyaluminium chloride and nanofiltration

2017 ◽  
Vol 15 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Marjana Simonič

AbstractLaboratory scale filtration tests utilizing leachate were conducted to investigate fouling and filtration performance of nanofiltration membranes. The work presented in this study is conducted on real samples rather than model water. Physico-chemical analyses showed that the leachate contained a lot of organic substances, exceeding 20000 mg/L O2 expressed as chemical oxygen demand. Proper pre-treatment method must be chosen in order to reduce fouling index. Coagulation pre-treatment using poly-aluminium chloride was chosen. Two thin film polysulfone membranes were used, purchased by Osmonic Desal. The focus of this research is to assess the influence of the particle size and zeta-potential of the colloidal fraction in leachate on nanofiltration performance. The isoelectric point of both membranes was 4.7 and 4.3, respectively. The fouled membranes were negatively charged over the pH range with isoelectric point shifting to the left (lower pH) indicating the foulant material mainly not charged. It was confirmed by its zeta-potential, measured at -2 mV.

2020 ◽  
pp. 204-220
Author(s):  
Zawawi Daud ◽  
Halizah Awang

In this chapter, the performance of combined treatment of municipal landfill leachate is reviewed. Although individual physico-chemical treatments are suitable for the removal of heavy metals and hydrolyzation of some organic compounds, a combination of two physico-chemical treatments or physico-chemical and biological is required for optimum treatment of stabilized landfill leachate. A combination of two physico-chemical treatments can give optimum results in removal of recalcitrant organic compounds from stabilized leachate, as reflected by a significant decrease of the COD values after treatment. On the other hand, a combination of physico-chemical and biological treatments is required to achieve effective removal of NH3-N and COD with a substantial amount of biodegradable organic matter. In many cases, physico-chemical treatments are suitable for pre-treatment of stabilized leachate. The objective of this paper is to highlight various types of integrated leachate treatments as it has been difficult to get optimum efficiency from single approached treatment.


2012 ◽  
Vol 66 (1) ◽  
pp. 217-223 ◽  
Author(s):  
Mouhamed el khames Saad ◽  
Younes Moussaoui ◽  
Asma Zaghbani ◽  
Imen Mosrati ◽  
Elimame Elaloui ◽  
...  

The present paper presents the main results of the biodegradation study of paper industry wastewater through physico-chemical treatment. Indeed, around 60% of chemical oxygen demand (COD) removal can be achieved by electroflocculation treatment. Furthermore, a removal efficiency of the COD of almost 91% has been obtained by biological treatment, with activated amount of sludge for 24 h of culture. Concerning the physico-chemical pre-treatment of the untreated, filtered and electroflocculated rejection effluents, it has been investigated through the degradation curve of COD studies.


2015 ◽  
Vol 802 ◽  
pp. 478-483 ◽  
Author(s):  
Mohd Faiz Muaz Ahmad Zamri ◽  
Mohd Suffian Yusoff ◽  
Hamidi Abdul Aziz ◽  
Mohd Anuar Kamaruddin

In this research, a physico-chemical treatment method of coagulation-flocculation process is implemented in treating partially stabilized leachate from Matang Landfill, Perak, Malaysia. Central composite design has been used to optimize the independent variables namely polyaluminum chloride (PAC) coagulant dosage (A), rapid mixing speed (B) and rapid mixing time (C). The experimental results were analyzed by using analysis of variance (ANOVA). The results revealed that the percentage of color and COD removal was found increased by increasing rapid mixing speed with optimum removal of 95 % and 56 % respectively. Besides, the R-squared values implied that 86.22 % and 97.34% of the total variation explained by the model equation. Furthermore, the model analysis revealed that rapid mixing speed were significant for removal of color and COD through single parameter (B) and interaction between parameter (AB) respectively. This finding proves the influence of mixing parameter in coagulation-flocculation process for leachate treatment.


Author(s):  
Zawawi Daud ◽  
Halizah Awang

In this chapter, the performance of combined treatment of municipal landfill leachate is reviewed. Although individual physico-chemical treatments are suitable for the removal of heavy metals and hydrolyzation of some organic compounds, a combination of two physico-chemical treatments or physico-chemical and biological is required for optimum treatment of stabilized landfill leachate. A combination of two physico-chemical treatments can give optimum results in removal of recalcitrant organic compounds from stabilized leachate, as reflected by a significant decrease of the COD values after treatment. On the other hand, a combination of physico-chemical and biological treatments is required to achieve effective removal of NH3-N and COD with a substantial amount of biodegradable organic matter. In many cases, physico-chemical treatments are suitable for pre-treatment of stabilized leachate. The objective of this paper is to highlight various types of integrated leachate treatments as it has been difficult to get optimum efficiency from single approached treatment.


2003 ◽  
Vol 18 (2) ◽  
pp. 495-506 ◽  
Author(s):  
Alejandro Vertanessian ◽  
Andrew Allen ◽  
Merrilea J. Mayo

The evolution of agglomerate structure during drying of particles from suspension has been studied for a nanocrystalline Y2O3 (8% mol fraction)-stabilized ZrO2 powder. Agglomerates in drying and dried suspensions were examined at the smallest size scales (1 nm to 1 μm) using ultra-small angle x-ray scattering (USAXS) and at the largest size scales (100 nm to 10 μm) using scanning electron microscopy. The results were correlated with the degree of particle dissolution in each suspension (measured by flame absorption spectroscopy of the suspension filtrate) and the zeta potential of the particles in suspension prior to drying. Results show that large agglomerates readily form across a pH range from 2 to 9. The fact that Y+3 ion dissolution varies by over four orders of magnitude in this range leads to the conclusion that there is little direct correlation between the degree of Y dissolution and agglomeration in this system (Zr ion dissolution was below the detection limit at all pH values studied). The observation of large agglomerates well before the introduction of air-water interfaces into the drying mass likewise leads to the conclusion that capillary forces are not essential to agglomerate formation. Instead, agglomerates appear to form as a direct consequence of increasing suspension concentration. Zeta potential also plays a role. Specifically, there was a notable change in agglomerate morphology as the isoelectric point was approached, at approximately pH 8. Here USAXS shows the particles in suspension to have a layered interior structure, with small primary particles aggregated in sheets to form each blocky particle. This is in contrast to the more rounded agglomerates formed away from the isoelectric point, which appear to be composed of the same primary particles arranged in chainlike structures. USAXS of powders from the dried suspensions confirms that the structures seen after drying are the same as those present in suspension. The two structural morphologies are attributed to diffusion-limited (sheets) versus reaction-limited (chains) aggregation, respectively.


Author(s):  
Eva Schmitz ◽  
Eva Nordberg Karlsson ◽  
Patrick Adlercreutz

AbstractThe establishment of sustainable bioeconomies requires the utilization of new renewable biomaterials. One such material currently seen as a waste product is oat hulls. Oat hulls exhibit a great potential for the production of dietary fibres due to their exceptionally large hemicellulose content (35%). Their recalcitrant structure however requires a suitable pre-treatment method to access and process the hemicellulose. After a screening of various physical, chemical and physico-chemical pre-treatment methods, including autoclaving, ultrasonication, microwave-, deep eutectic solvents-, as well as alkaline treatments, a combined ultrasonication and alkali pre-treatment method was here found to be the most suitable. A factorial design resulted in optimized conditions of 10 min ultrasonication in water, followed by an incubation in 5 M NaOH at 80 ºC for 9 h yielding solubilisation of 72% of all hemicellulose in the hulls. The method was shown to efficiently break the ester bonds between ferulic acid and the hemicellulose main chain, contributing to its solubilisation. Graphic Abstract


2013 ◽  
Vol 11 (1) ◽  
pp. 46-56 ◽  
Author(s):  
Viktor Pauer ◽  
Edit Csefalvay ◽  
Peter Mizsey

AbstractThe soy bean process water that is a by-product of soy processing technology can be utilized with a hybrid separation system recommended and investigated in this work. The aims of the soy bean water processing are to i.) concentrate the valuable components of the soy process water and ii.) reuse its water content. Two hybrid separation systems are considered and investigated: ultrafiltration followed by nanofiltration and centrifugal separation followed by nanofiltration. These hybrid separation systems are new in the area of their current application. Experiments verify that centrifugal separation is a more appropriate pre-treatment method for the removal of suspended solids and for the preservation of the sucrose content of the soy bean process water than ultrafiltration. Total sucrose can be rejected by nanofiltration membrane forming a sugar-rich retentate that contains other valuable components, too. Both tested hybrid processes result in clear and reusable permeates with low chemical oxygen demand that can be recycled to the production process reducing its water consumption and improving its sustainability. The recommended new hybrid separation system, centrifugal separation followed by nanofiltration, proves to be successful in this area of the biochemical industry.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3136
Author(s):  
Marek Kosmulski ◽  
Edward Mączka

The pH-dependent surface charging of tellurium (IV) oxide has been studied. The isoelectric point (IEP) of tellurium (IV) oxide was determined by microelectrophoresis in various 1-1 electrolytes over a concentration range of 0.001–0.1 M. In all electrolytes studied and irrespective of their concentration the zeta potential of TeO2 was negative over the pH range 3–12. In other words the IEP of TeO2 is at pH below 3 (if any). TeO2 specifically adsorbs ionic surfactants, and their presence strongly affects the zeta potential. In contrast the effect of multivalent inorganic ions on the zeta potential of TeO2 is rather insignificant (no shift in the IEP). In this respect TeO2 is very different from metal oxides.


2015 ◽  
Vol 17 (3) ◽  
pp. 439-450 ◽  

<div> <p>Raw municipal landfill leachate is extremely polluted wastewater and it regards as one of the drawbacks of the sanitary landfill treatment method. If the untreated landfill leachate is discharged to the natural environment, a great problem for the environment can be created, particularly for the water resources. To assess fresh leachate; collection, analyzing for various parameters, and comparing with the standards are essential. Thus, this study was purposed to examine the characteristics of different landfill leachate samples collected from three tropical landfill sites. The results of the formed leachate at the anaerobic Kulim Sanitary Landfill, semi-aerobic Pulau Burung Landfill Site, and anaerobic Kuala Sepetang landfill leachate in the northern region of Malaysia have been analyzed for 27 parameters and compared. The studied parameters in the present study were&nbsp; phenols, zeta potential, oxidation-reduction potential (ORP), chemical oxygen demand (COD), biochemical oxygen demand (BOD<sub>5</sub>),&nbsp; heavy metals, nitrogen compounds, salinity, electrical conductivity etc. For checking the risks of the leachate on the environment, the obtained results were compared with the Malaysia Standards. In addition, the leachate treatment opportunities upon the characterization are highlighted in this study. The effectiveness of various applications in treating leachate collected from municipal landfill was presented and discussed. It could be concluded that the knowledge of leachate quality is particularly significant in choosing an appropriate treatment techniques</p> </div> <p>&nbsp;</p>


2017 ◽  
Vol 13 (33) ◽  
pp. 154 ◽  
Author(s):  
Zakariae Mejraoua ◽  
Nasser-Eddine Zine

Solid and urban waste produced by the municipality of Meknes amounts to more than 185.103 tons annually. Since 2002 they have been transported to a landfill controlled, wild of an area of 23 hectares on the outskirts of the Commune. This discharge is unfortunately devoid of a leachate treatment device (brownish liquid effluent, produced under the combined action of rainwater and fermentation of buried waste). This study aims to make a physico-chemical characterization and evaluate the states mineral and organic of this leachate. It should be noted that this physicochemical characterization is arbitrary because this discharge will soon be equipped with a waste disposal and recovery center (CEV) using Evalixm as a treatment method. Since 2014, the company '' SUEZ ''Environment began to put in place under control this discharge. For the realization of this characterization, we carried out a series of sampling leachate from June 2014 to June 2015. During this period, the physico-chemical analyzes carried out on these samples, revealed: - low levels of nitrates (NO3 - max = 18,1 mg / L) and phosphates (PO4 3- max = 0,38mg / L) - high levels of ammonium (NH4 + max = 54,13 mg / L) and nitrites (NO 2 - , max = 27,67mg / L). This mineral concentration is translated by a high electrical conductivity which has reached a maximum value of 7.35 10 3 μS / cm. Organic pollution estimated by the pollutant load is important; the values of the Calculated DCO from 1205 to 9207 mg O2 / L with an average of 4808 mg O2 / L, those of DBO are between 53 and 386 mg O2/ L for an average of 157 mg O2 / L. The values of the ratio DBO5 / DCO oscillate between 0.01 and 0.08 with an average of 0.04. This which testifies to the anaerobic character that prevails at the level of the discharge and a probable contamination of the water table. The hydrogen variant (pH) between 6,42 and 8,99 is an annual average of 8,42 which shows that the leachate produced by the landfill is basic. The pH value shows a stagnation (8.42 and 8.23) from one year to the next, reflecting its stability and aging


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