Search

The performance of limestone and anthracite coal were evaluated for the removal of pollutants from groundwater. The physical and chemical properties of two filter materials were characterised through X-Ray diffraction (XRD), X-Ray fluorescence (XRF), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD analysis showed that the main peaks of calcite (CaCO3) are the predominant phase of limestone, whereas quartz and graphite are the crystalline phase of anthracite coal. The presence of calcium oxide (CaO) as the major composition indicated that limestone demonstrates a good ability for cation exchange. FTIR spectrum analysis showed that the functional groups present on the limestone surface are mostly hydrophilic groups, and anthracite exhibits hydrophobic characteristic. Limestone has the potential to adsorb heavy metal pollutants, whereas anthracite has the capability to adsorb organic pollutants. Therefore, the two filter materials can be used as alternatives to remove pollutants in treating groundwater.

The current review aims at improving the understanding on the treatment frameworks related to poultry slaughterhouse wastewater (PSWW) treatment efficiency. Technologies used for nutrient and organ...

Clayey composite liners are appointed in modern landfills to isolate wastes from the environment and minimise the escape of contaminants that are affecting the groundwater and the subsoil. Enhanced compressibility and reduced permeability are considered favourable; however, the ameliorating liners are at risk of losing these properties and thus the ability to contain the contaminant due to changing pH and contaminant contents during the long course of service. This research investigated the change in the mechanical properties, namely, the compression index c c, permeability coefficient K and void ratio–effective stress curve e against log σ′ of bentonite clay treated with chemically modified sawdust contents and laced with various lead nitrate (Pb(NO3)2) concentrations. The optimum values were simultaneously achieved for c c and K, in the 10% sawdust of pH 10 design, with lead (Pb) concentration

Wastewater treatment is crucial to prevent environmental pollution [...]

This review of literature published in 2016 focuses on waste related to chemical and allied products. The topics covered include waste management, aerobic waste treatment, anaerobic waste treatment, air emission, biological waste treatment, groundwater remediation, water recycle, water analysis, water reuse, soil remediation, sorption, physicochemical treatment, ozonation, and fertilizer waste. Future topics include the pollution effect on the environment, especially, to the ecosystem and human as well as improved treatment processes to alleviate the detrimental effects.

Recycled paper mill effluent (RPME) contains high levels of organic and solid compounds, causing operational problems for anaerobic biological treatment. In this study, a unique modified anaerobic inclining-baffled reactor (MAI-BR) has been developed to treat RPME at various initial chemical oxygen demand (COD) concentrations (1000–4000 mg/L) and hydraulic retention times (HRTs) (3 and 1 day). The COD removal efficiency was decreased from 96 to 83% when the organic loading rate (OLR) was increased from 0.33 to 4 g/L day. Throughout the study, a maximum methane yield of 0.25 L CH4/g COD was obtained, while the pH fluctuated in the range of 5.8 to 7.8. The reactor performance was influenced by the development and distribution of the microbial communities. Based on the next-generation sequencing (NGS) analysis, the microbial community represented a variety of bacterial phyla with significant homology to Euryarchaeota (43.06%), Planctomycetes (24.68%), Proteobacteria (21.58%), Acidobacteria (4.12%), Chloroflexi (3.14%), Firmicutes (1.12%), Bacteroidetes (1.02%), and others (1.28%). The NGS analysis showed that the microbial community was dominated by Methanosaeta concilii and Candidatus Kuenenia stuttgartiensis. This can be supported by the presence of filamentous and spherical microbes of different sizes. Additionally, methanogenic and anaerobic ammonium oxidation (ANAMMOX) microorganisms coexisted in all compartments, and these contributed to the overall degradation of substances in the RPME.

Biodiesel has become a source of renewable energy that is in immense demand due to the rise in price of fuels and its utilization to produce various conventional assets. Biodiesel has gained wide attention as it emits less carbon monoxide and other pollutants, compared to that of fossil diesel. In this work, biodiesel was synthesized from waste frying oil (WFO) using a microwave-assisted transesterfication process under various operating conditions including microwave power, irradiation time, temperature, and catalyst dose. The Box–Behnken design was used to examine the biodiesel yield. Numerical optimization technique was used to obtain the maximum biodiesel production, which was found to be using a microwave power of 325 W, an irradiation time of 200 s, a temperature of 70°C, and a catalyst dose of 1 g/g. Using these conditions, a biodiesel production yield of 97% was achieved. Fuel properties of the synthetized biodiesel were compared with the ASTM D6751 biodiesel standards.

The increasing growth of the seafood processing industries considerably requires more industrial process activities and water consumption. It is estimated that approximately 10–40 m3 of wastewater is generated from those industries for processing one-tonne of raw materials. Due to limitations and regulations in natural resources utilization, a suitable and systematic wastewater treatment plant is very important to meet rigorous discharge standards. As a result of food waste biodegradability, the biological treatment and some extent of swim-bed technology, including a novel acryl-fibre (biofilm) material might be used effectively to meet the effluent discharge criteria. This chapter aims to develop understanding on current problems and production of the seafood wastewater regarding treatment efficiency and methods of treatment.

Anaerobic digestion is widely considered as an environmentally friendly technology for various organic waste including sewage sludge. Although the implementation of anaerobic digestion as an alternative treatment method for sewage sludge can be seen in many countries, its status in Malaysia is not clear. This study reviewed the current state of sewage sludge treatment in Malaysia and discussed the challenges to promote anaerobic digestion in sewage sludge treatment. Other than the common constraints faced, namely technical, political and economic, the characteristics of sewage sludge in Malaysia are considered to be a factor regarding feasibility. Anaerobic co-digestion is the simultaneous anaerobic digestion of two or more substrates which is a promising possible option to overcome the disadvantages of mono-digestion, and improve the economic viability due to higher methane production. There are a variety of biomasses as co-substrates in Malaysia. However, the anaerobic co-digestion of food waste and sewage sludge might be the most feasible method to overcome such constraints. Adding food waste as co-substrate is suggested as the possible approach to not only improve the process's performance but also help to handle the increasing volume of food waste in Malaysia. This study aims to highlight the potential as well as to provide a starting point for further studies regarding the treatment of sewage sludge using anaerobic digestion in Malaysia.

This work illustrates a comparative study on the applicability of the natural calcium oxide (CaO) prepared from waste eggshells and chemical CaO as basic heterogeneous catalyst in the transesterifi...

One of the main contributors to the waste generated in the Malaysian construction industry is housing projects. The construction waste has increased over years, creating environmental problems and profit loss to contractors. Limited data are available to date in Malaysia, especially in terms of sources, types and quantity. The aim of this study is to explore the causes and contributory factors that cause waste generation in selected housing project followed by quantification of common waste generated at sites. Site observation and interviews with labors and site management was conducted in determining the waste sources and waste management practices. Management and workers were the main causes of waste generated in this study.

Landfill leachate is a hazardous pollutant generated from a landfill site. Discharge of landfill leachate has caused a major contamination to the environment and detrimental to human health. This chapter introduces an alternative method to treat recalcitrant pollutant in leachate by using ozonation with catalyst. The production of hydroxyl radical in ozonation was not enough to oxidize complex molecular structure in the leachate. Theoretically, the addition of catalyst enhances the capacity of radical and accelerates the chemical reaction. The effectiveness of ozonation with Fenton (O3/Fenton), hydrogen peroxide (O3/H2O2), and zirconium tetrachloride (O3/ZrCl4) in removing pollutant such as chemical oxygen demand (COD), color, and improvement of biodegradability by using this process were also discussed in this chapter. Comparison in term of treatment cost and benefits of the application of chemical as catalyst are briefly elaborated at the end of this chapter.

Advanced oxidation processes (AOPs) have recently received attraction for treatment of different wastewaters. AOPs have an ability to oxidize a high quantity of refractory organic matters, traceable organic, or to increase wastewater biodegradability as a pre-treatment prior to an ensuing biological treatment. In this chapter, the fundamental mechanisms of different AOPs such as ozonation, hydrogen peroxide, UV, persulfate, and Fenton oxidation are summarized. The combination of different oxidation processes such as O3/H2O2, O3/UV, O3/Fenton+, O3/persulfate are evaluated. Several persulfate activation techniques are also summarized.

In this study, three start-up techniques of modified anaerobic inclining-baffled reactor (MAI-BR) were performance to understand the effect of inoculum source and effluent recycle on the treatment of recycled paper mill effluent (RPME). Flocculant anaerobic sludge from a palm oil mill pond and digested anaerobic sludge from a sewage treatment plant were inoculated in the first and second start-up/phase1, respectively. Results show that high chemical oxygen demand (COD) removals of 93 and 88% were achieved in the first and second start-up/phase1, respectively. The amount of methane produced in the second start-up/phase1 within 15 d was doubled as compared to the amount produced in the first start-up, with a higher methane content of 79% (as compared to 62% in the first start-up). This result indicated that the inoculum source has a significant effect on the reactor performance. The results in the second start-up/phase2 also showed that COD removal and methane production increased up to 94% and 0.52...

Waste generated in construction sites has recently increased and has become an uncontrollable cause of environmental problems and profit loss to contractors. The lack of real data or research on such wastes is due to the lack of suitable policies regarding this issue. The actions of contractors are not controlled by rules on this issue. This situation leads to the lack of action or awareness on the side of the contractor. Concrete waste is also part of the waste generated in construction sites. We determine the concrete waste generated in construction stages and conduct multiple linear regression analysis of the amount of column waste generated. The methodology employed in this study involves site observations, interviews with site personnel, and sampling at housing construction sites. The estimation method is utilized for the sampling of concrete waste. Results show that the average percentage of column waste is 13.93% and that of slab waste is 0.34%. These percentage values are derived from the total order of the concrete. The difference is due to the sizes of structures and method of handling. The regression model obtained from the sample data on column waste resulted in an adjustedR2value of 0.895. Therefore, the model predicts approximately 89.5% of the factors involved in concrete waste generation.

As a developing country and one of the tropical tourism industry leaders, Malaysia is faced with environmental problems, such as the conversion of municipal solid waste landfill leachate into hazardous wastewater in mega cities. High concentrations of pollutants, toxic refractory component, and complex composition of landfill leachate have serious environmental impact. This study investigated a novel rapid treatment method to remove turbidity, suspended solid, color, and ammonia nitrogen. Bentonite augmented sequencing batch reactor with miscellaneous aeration (0.5–7.5 L/min) and contact time (1–3 h) is applied via response surface methodology in 13 runs. Results of this study show that in optimum circumstances, 93.63% of turbidity, 90.42% of total suspended solid, 76.33% of ammonia nitrogen (AN), and 45.96% color were removed in only three hours. Furthermore, natural bentonite is a cost effective adsorbent for landfill leachate treatment.

This paper reviews the related literature reported in 2019 about various types of wastewaters associated with chemical and allied products. The subjects comprise wastewaters produced from various activities in agricultural, chemical, dye, petrochemical, and pharmaceutical. PRACTITIONER POINTS: Bioflocculant chitosan was used for sludge dewatering and the treatment of water and wastewater, and polishing of sanitary landfill leachate. Alkaline lignin-based flocculants were used to achieve excellent color removal for paper mill sludge. Powdered activated coke was used to remove COD (chemical oxygen demand) from chemical industry wastewater effluents.

Landfill leachate generation is one of the main problems from sanitary landfill. Chemical oxygen demand (COD), ammoniacal nitrogen (NH3-N), and color are among the most problematic parameters in stabilized leachate. In this regard, dedicated treatment facilities are required before leachate can be discharged into the environment. The performance of the combined ozonation (O3) and zirconium tetrachloride (ZrCl4) to treat two types of stabilized leachate was investigated during this study. Leachate samples were collected from an anaerobic stabilized leachate (Alor Pongsu Landfill Site, APLS) and semi-aerobic stabilized leachate (Pulau Burung Landfill Site, PBLS). Zirconium tetrachloride dosage was determined as 1 g/1 g (COD/ZrCl4 ratio) and then added to the leachate samples with 60 min ozonation at natural leachate pH (8). COD, color, and NH3-N were removed from the APLS sample at 33%, 70%, and 53% rates, respectively, whereas 48%, 75%, and 69%, respectively, from the PBLS samples. Ozone consumption was also calculated with the highest value (3.81 Kg O3/ Kg COD) reported in PBLS, whereas the lowest value (2.32 Kg O3/ Kg COD) was reported in APLS. Biodegradability of (BOD5/COD) was investigated and improved from 0.07 to 0.08 for the APLS samples and 0.05 to 0.11 for the PBLS samples after leachate oxidation. Results showed that the performance of O3/ZrCl4 oxidation is more efficient in treating semi-aerobic stabilized leachate than anaerobic stabilized leachate Moreover, the combined method proved to be more efficient in remediating leachate compared with ozone and zirconium treatment alone.

This study evaluated the performance of sequencing batch reactor (SBR) with and without the fibers of poultry slaughterhouse wastewater (PSWW). The fibers act as attachment materials to the suspended solids, which are considered as pollutant in PSWW. PSWW contains high-pollutant concentrations. Experiments were conducted using two 60 L laboratory SBR reactors at room temperature (25 °C) and pH 7±0.5. The removal percentage of SBR with and without the fibers was compared in terms of chemical oxygen demand and biological oxygen demand. The removal percentage of SBR with fibers showed higher overall performance, which was approximately 90%. Meanwhile, the removal of SBR without fibers achieved an average percentage of about 70%, which was slightly lower compared with SBR reactor with fibers.

At the ambient temperatures, the influence of operating conditions on persulfate (S2O8) oxidation of real textile wastewater was investigated for the removal of color, suspended solids (SS) and chemical oxygen demand (COD). The effects of oxidant dosage, initial solution pH and contact time were studied in a series of batch experiments using persulfate (PS) oxidant as sodium persulfate. Oxidant dose was defined by an oxidant/contaminant (PS/COD) molar ratio, varied from 1/1-10/1. Although parameter removals increased with the oxidant dose, especially for color and SS, a PS/COD molar ratio of 4/1 (6720mg/L) was adopted in a bid to use fewer chemicals. The pH was varied from 2-11, with pH of between 2 and 3 being the optimum. At 360minutes contact time, the removals of color, SS and COD were 84%; 71% and 32% respectively. Although relatively effective, especially for color removal, results show that the reactions might have been inhibited at ambient temperatures as shown by the particularly low removal of COD.

Three start-up techniques were investigated to evaluate the suitability of the bench-scale modified anaerobic inclining-baffled reactor (MAI-BR) for the treatment of recycled paper mill effluent (RPME) and to achieve an improved understanding of the inoculum to substrate ratio (ISR). The ISR ratios used were 3.53, 1.17, and 10.63 g volatile suspended solids (VSS)/g chemical oxygen demand (COD) for the first, second, and third start-ups, respectively. On a 30-d duration, the first start-up succeeded in removing 72% of the COD with an effluent pH of 6.2 and a methane production of 0.076 L/d. The second start-up was considered unfavorable after 16 d because of low methane production and effluent pH level. The third start-up with a 21-d duration was the best because of its 87% COD removal, 6.82 effluent pH, and 0.164 L/d methane production. The effluent volatile fatty acid (VFA)/alkalinity ratios were concurrently varied as 0.56, 0.45, and 0.034 for the first, second, and third start-ups, respectively...

This chapter describes the manufacturing processes, energy requirement, waste characterization, environmental impacts, pollution prevention and abatement, treatment technologies, costs, monitoring, global overview, and standard requirement of air emission and effluents discharge of the chlor-alkali industry. The caustics chain begins with sodium chloride (NaCl) and forms the basis for what is often referred to as the chlor-alkali industry. Major products of the chlor-alkali industry, include chlorine, sodium hydroxide, soda ash, sodium bicarbonate, potassium hydroxide, and potassium carbonate. In the diaphragm process, there are two compartments, which are anode and cathode separated by a permeable diaphragm, often made of asbestos fiber. Membrane cells are acknowledged as most efficient for chlor-alkali. The hydrogen gas from chlor-alkali cells is usually used for the production of hydrochloric acid or as a fuel to produce steam. The solution-mined brine or the solid salt dissolved in a salt dissolver is treated in a reactor with sodium carbonate and caustic soda to precipitate calcium carbonate and magnesium hydroxide.

Landfill leachate is a complex liquid that contains excessive concentrations of biodegradable and non-biodegradable products including organic matter, phenols, ammonia nitrogen, phosphate, heavy metals, and sulfide. If not properly treated and safely disposed, landfill leachate could be an impending source to surface and ground water contamination as it may percolate throughout soils and subsoils, causing adverse impacts to receiving waters. Lately, various types of treatment methods have been proposed to alleviate the risks of untreated leachate. However, some of the available techniques remain complicated, expensive and generally require definite adaptation during process. In this article, a review of literature reported from 2008 to 2012 on sustainable landfill leachate treatment technologies is discussed which includes biological and physical–chemical techniques, respectively.

Leachate is a major pollution source associated with municipal solid waste landfill. This study was carried out to evaluate the effectiveness of various techniques in treating mature landfill leachate generated from landfill in Malaysia, a tropical country. Treatment processes such as biological, ion exchange, coagulation–flocculation, adsorption, advanced oxidation processes (AOPs), and flotation were analyzed. The efficiency of each process was analyzed based on chemical oxygen demand (COD), color, and NH3-N percentage removals. Ion exchange treatment via cationic/anionic sequence achieved the best removal of color (96.8%), COD (87.9%), and NH3-N (93.8%) from leachate as compared with other treatment methods. Coagulation–flocculation and AOPs were successful for COD and color removals from leachate. However, both could not treat NH3-N effectively. Biological treatment could remove NH3-N (71%) effectively, but it was poor in terms of COD (29%) and color (22%) removals. Adsorption via a new carbon...

The characterization of landfill leachate has been well established. However, its biodegradation properties have not been well reported. Therefore, this research was undertaken to investigate the biodegradability of semi-aerobic sanitary landfill and the ratio of the biological oxygen demand (BOD) to chemical oxygen demand (COD) BOD5/COD, COD fraction on leachate from Pulau Burung landfill Site (PBLS). These parameters are important as they may provide appropriate and suitable treatment for this kind of leachate. In this research, leachate from two different ponds were studied i.e., the raw leachate from leachate collection pond and the leachate effluents of the treatment plant'. Five different measurement points were tested for each pond to understand the characterization for leachate. The soluble and particulate organic compound was separated by filtration using a 0.45μm pore size membrane filter. The results indicated that leachate in PBLS has low BOD5/COD ratio. The total COD (TCOD) ranged from 2040mg/L to 3160mg/L. The Biodegradable COD (BCOD), unbiodegradable COD (UBOD), soluble biodegradable (RBCOD), particlulate biodegradable (SBCOD), particulate inert (UPCOD), and soluble inert (USCOD) ranged from 53%-67%, 33%-47%, 38%-46%, 9%-25%, 12%-26%, and 18%-25%. This indicates, the leachate in Pulau Burung Landfill Site have different of COD fraction behavior compare with domestic wastewater. In which, leachate have low SBCOD, but relatively high in others COD fraction compare with domestic wastewater.

Rice straw can be used in the production of energy or organic fertilizer. However, one of the main problems in the transformation of rice straw is its low-biodegradability. This study reports a comparison on the effectiveness of the Sodium Hydroxide (NaOH) and Potassium Hydroxide (KOH) pre-treatment methods on the enhancement of rice straw solubilization to increase its biodegradability. Laboratory-scale experiments were carried out in reflux completely mixed reactors of 500 mL capacity. The Response Surface Method (RSM) was used to optimize experimental conditions. The respective optimum conditions determined from RSM for NaOH and KOH were as follows: concentration of 29.99 and 30 g/L, reaction time of 165.7 and 151.23 min, and temperature of 164.37 and 200°C. The actual and predicted results are clearly indicated that the solubility of rice straw is significantly increased under NaOH pretreatment in comparison with KOH. The actual results of solubility of rice straw under optimum conditions are compared well with the maximum predicted values.

The reduction of the duration of start-up and the improvement of process control are important factors in order to increase the competitiveness of anaerobic baffled reactor systems. In this paper, the start-up performance of modified anaerobic baffled reactor (MABR) in treating recycled paper mill (RPM) wastewater at batch and continuous phases was investigated. In batch phase, about 3.5 L (10 d HRT) of RPM wastewater were added daily to the reactor for 9 days, while 7 L/day (5 d HRT) was pumped into the reactor during the continuous phase. During batch and continuous phase, it was found that methane yield increased significantly from 0.003 to 0.09 L CH4/g COD day. During the whole start-up operation, the system demonstrated a remarkable performance of high COD removal efficiency (up to 71%) on day 30. Nevertheless, the pH was slightly decreased (from 7.3 to 6.2) during the period of phase 1 (batch) and phase 2 (continuous).

Adsorption has been known as the most acceptable method for removal of refractory compounds in textile waste water treatment. Owing to its ability in terms of physical and chemical sorption, a wide range of precursors origin from natural resources, synthesized materials and agricultural wastes as the starting materials for adsorbents purpose have been tested via adsorption technique. Over the years, scientists have begun searching for a sustainable replacement of the conventional adsorbents due to expensiveness, poor mechanical properties and limited applications. Lately, focus has been paid on the potential of locally available materials, inexpensive, easier to obtain, good mechanical properties and high adsorption capacities that can be converted into adsorbent. The present article highlights recent developments of textile waste water treatment by adsorption process. A critical discussion with regard to textile waste water characteristics, textile operation and adsorption by various adsorbent were also included in this review.

Sequencing batch reactor (SBR) process uses for treatment of different types of wastewaters such as municipal wastewater, landfill leachate, dairy wastewater, slaughterhouse wastewater etc. Operation parameters of SBR technique are cycle time, aeration rate, volume of reactor, hydraulic retention time (HRT) and other parameters. In this work, operational parameters and removal efficiencies of pollutants for SBR method were studied. In addition, boundaries for operational parameters in SBR process were explained as well.

Among numerous techniques, electro-oxidation occupies a noticeable place in landfill leachate treatment. In recent years, electro-oxidation processes have been shown to be effective alternative for the removal of refractory organic compounds from stabilized landfill leachate. This paper aims to provide an overview about the effectiveness and mechanism of electro-oxidation processes employed for stabilized landfill leachate treatment. A review of the recent literature published on the electro-oxidation processes (i.e. electrochemical, electro-Fenton, photoelectro-Fenton, photoelectrochemical, and electrochemical peroxidation) performance and efficiency in stabilized leachate treatment are summarized and presented in this study. This study concluded that, although the high treatment cost caused by the energy consumption may limit electro-oxidation techniques, electro-oxidation processes are still a promising and effectual technology for the reduction of pollutants in stabilized landfill leachate.

Leachate is created while water penetrates through the waste in a landfill, carrying some forms of pollutants. The aims of this study were the review on physical-chemical methods for landfill leachate treatment. The physical-chemical ways for landfill leachate treatment like Chemical precipitation, Chemical Oxidation, Coagulation-Flocculation, Membrane filtration, Ion exchange, Adsorption and Electrochemical treatment are studied. Chemical precipitation is generally used as pre- treatment in order to remove high strength of ammonium nitrogen; fenton oxidation is one of these advanced oxidation processes with high efficiency and low capital costs; coagulation-flocculation has been used for the removal of non- biodegradable organic compounds and heavy metals from landfill leachate; nanofiltration (NF) is one of membrane filter and it has found a place in the removal of recalcitrant organic compounds and heavy metals from landfill leachate; adsorption is the most widely used technique for the removal of recalcitrant organic compounds from landfill leachate; the ion-exchange method offers a number of benefits containing the ability to handle shock loadings and operate over a wider range of temperatures. The landfill leachate properties, technical applicability and constraints, effluent discharge alternatives, cost-effectiveness, regulatory requirements and environmental impact are important factors to selection of the most suitable treatment technique for landfill leachate treatment. Key word: Adsorption method, Chemical Oxidation, Ion exchange, Leachate, Membrane filtration

One of an anaerobic stabilized landfill leachate in Malaysia underwent ozonation process. The sample rich in chemical oxygen demand (COD) was collected from Alor Pongsu Landfill Site, Perak (APLS). This site has been operating since year 2000. The leachate also contains other pollutants that exceeded the standard discharge limit for wastewater effluents. The effectiveness of ozone (O3) dosage, pH variation, and reaction time during ozonation was evaluated to measure the performance of O3 and determine the maximum operational conditions for this treatment. The maximum removal efficiency for COD was 50% at an ozone dosage of 31 g/m3, natural of pH 8.5, and reaction time of 60 min. The biodegradability ratio (BOD5/COD) improved from 0.08 to 0.23 after treatment with O3. The ozonation method has enhanced the biodegradability ratio and resulted high percentage removal of COD. This improvement showed that oxidation has a great potential to remediate recalcitrant pollutant wastes, such as landfill leachate.

This paper describes the investigation of solidification and stabilization (S/S) process for the safe disposal of incinerated wastewater sludge produced from a textile industry in Penang, Malaysia. Physical and chemical properties of the samples were first characterized. Various ratios of ordinary Portland cement (OPC) as a binder were used to immobilize the metals. The leachability of metals in these cement-based waste materials was studied by standard toxicity characteristic leaching procedure (TCLP) and the mechanical strength was tested by a compressive strength test. TCLP results showed the ability of OPC to immobilize various metals such as Zn, Cu, Fe, Al, Ti, and K within the limits set by USEPA and Malaysia Environment Quality Act, 1974. However, the strength of the solidified matrixes was generally lower than the control specimens, ranging from 1-23 Mpa, which was well above the specified limit of 414 kPa for such matrices for their disposal in landfills.

The current study aimed to evaluate the performance of employing the solar photocatalyst of TiO2/Fenton/ZnO process to treat petroleum wastewater. The operating factors such as TiO2 dosage, ZnO dosage, Fenton-reagent concentration, and pH were evaluated to identify the optimum operational conditions of the treatment process. The obtained optimum conditions were a TiO2 dosage (0.5 g L−1), ZnO dosage (0.5 g L−1), Fenton ratios 100 (1 g L−1 H2O2/0.01 g L−1 Fe2+), and pH 7. The treatment efficiencies were significantly improved by adding of ZnO/Fenton with the solar photocatalyst of TiO2 process. The removal efficiencies increased from 18% to 88% for TOC and from 24% to 61% for COD at pH 7, therefore no need to adjust pH during this treatment. The treatment time was reduced up to 150% compared with the photocatalyst of TiO2 process. Using renewable solar energy and treating with minimum chemical input make this method to be a unique treatment process for petroleum wastewater.

Generally, the rainwater has low concentration of pollutants, whereby it is applicable for domestic water supply. Due to the low concentration of pollutants, further treatment such as adsorption is necessary to treat the harvested rainwater as an alternative source of drinking water supply. Therefore, this research has been carried out to determine the quality of rainwater from different types of locations, which are; rural residential area, urban residential area, agricultural area, industrial area, and open surface. The rainwater sampling was carried out from September 2014 to December 2015. The parameters that have been analysed during the sampling process are chemical oxygen demand (COD), turbidity, heavy metals, and Escherichia coli (E.coli). The sampling results show that the rainwater provides low concentration of contaminants. Thus, it has high potential to be used as alternative source of potable and non potable water supply with a suitable treatment. Due to that, an experimental work contained o...

Petroleum hydrocarbon waste is produced in worldwide refineries in significant amount. In Libya, approximately 10,000 tons of oil sludge is generated in oil refineries (hydrocarbon waste mixtures) annually. Insufficient treatment of those wastes can threaten the human health and safety as well as our environment. One of the major challenges faced by petroleum refineries is the safe disposal of oil sludge generated during the cleaning and refining process stages of crude storage facilities. This paper reviews the hydrocarbon sludge characteristics and conventional methods for remediation of oil hydrocarbon from sludge. This study intensively focuses on earlier literature to describe the recently selected innovation technology in oily hydrocarbon sludge bioremediation process. Conventional characterization parameters or measurable factors can be gathered in chemical, physical, and biological parameters: (1) Chemical parameters are consequently necessary in the case of utilization of topsoil environment when they become relevant to the presence of nutrients and toxic compounds; (2) Physical parameters provide general data on sludge process and hand ability; (3) Biological parameters provide data on microbial activity and organic matter presence, which will be used to evaluate the safety of the facilities. The objective of this research is to promote the bioremediating oil sludge feasibility from Marsa El Hariga Terminal and Refinery (Tobruk).

Anaerobically treated palm oil mill effluent (POME) used as an infant in the aerobic sequencing batch reactor (SBR). Three different treatments such as 15 g/L zeolite, municipal wastewater (MWW) and combining zeolite and municipal wastewater in comparing with the only aeration used in a lab scale batch study. Spectrophotometric analysis carried out for chemical oxygen demand (COD), ammonia nitrogen, total suspended solids, colour and total phosphorus as target characteristics of raw and treated POME. Zeolite and MWW augmented SBR contain POME + zeolite + MWW had significantly more performance compared with POME (blank) in all analyzed target factors. The results of this study indicate that MWW has significantly higher influence in decontamination of POME in comparing with zeolite. Combining zeolite and MWW in aerobic SBR could meet Malaysian environmental discharge for POME in 22 hours.

This study investigates the treatability of composite adsorbent made from waste materials and minerals which is widely available in Malaysia. The composite adsorbent was prepared based on wet attrition method which focuses on the determination of optimum dosage of each of raw materials amount by conventional design of experiment work. Zeolite, activated carbon, rice husk and limestone were ground to obtained particle size of 150 µm. 45.94% zeolite, 15.31% limestone, 4.38% activated carbon, 4.38% rice husk carbon and 30% of ordinary Portland cement (OPC). The mixture was mixed together under pre-determined mixing time. About 60% (by weight) of water was added and the mixture paste was allowed to harden for 24 hours and then submersed in water for three days for curing. Batch experimental study was performed on synthetic dissolving a known amount of solid crystal phenol with distilled water into the volumetric flasks. From the batch experimental study, it was revealed that the optimum shaking speed for remo...

Palm oil mill effluent (POME) is the largest wastewater in Malaysia. Of the 60 million tons of POME produced annually, 2.4–3 million tons are total solids. Turbidity is caused by suspended solids, and 75% of total suspended solids are organic matter. Coagulation and flocculation are popular treatments for turbidity removal. Traditional commercial treatments do not meet discharge standards. This study evaluated natural zeolite and municipal wastewater (MWW)-augmented sequencing batch reactor as a microbiological digestion method for the decontamination of POME in response surface methodology. Aeration, contact time, and MWW/POME ratio were selected as response factors for turbidity removal. Results indicated that turbidity removal varied from 96.7% (MWW/POME ratio=50 %, aeration flow=0.5 L/min, and contact time=12) to 99.31% (MWW/POME ratio=80%, aeration flow 4L/min, and contact time 12 h). This study is the first to present MWW augmentation as a suitable microorganism supplier for turbidity biodegradation in high-strength agroindustrial wastewater.

This book provides in-depth coverage of environmental pollution sources, waste characteristics, control technologies, management strategies, facility innovations, process alternatives, costs, case histories, effluent standards, and future trends in waste treatment processes. It delineates methodologies, technologies, and the regional and global effects of important pollution control practices. It focuses on toxic heavy metals in the environment, various heavy metal decontamination technologies, brownfield restoration, and industrial, agricultural, and radioactive waste management. It discusses the importance of metals such as lead, chromium, cadmium, zinc, copper, nickel, iron, and mercury.

Ozonation, combined with the Fenton process (O(3)/H(2)O(2)/Fe(2+)), was used to treat matured landfill leachate. The effectiveness of the Fenton molar ratio, Fenton concentration, pH variance, and reaction time were evaluated under optimum operational conditions. The optimum removal values of chemical oxygen demand (COD), color, and NH(3)-N were found to be 65%, 98%, and 12%, respectively, for 90 min of ozonation using a Fenton molar ratio of 1 at a Fenton concentration of 0.05 mol L(-1) (1700 mg/L) H(2)O(2) and 0.05 mol L(-1) (2800 mg/L) Fe(2+) at pH 7. The maximum removal of NH(3)-N was 19% at 150 min. The ozone consumption for COD removal was 0.63 kg O(3)/kg COD. To evaluate the effectiveness, the results obtained in the treatment of stabilized leachate were compared with those obtained from other treatment processes, such as ozone alone, Fenton reaction alone, as well as combined Fenton and ozone. The combined method (i.e., O(3)/H(2)O(2)/Fe(2+)) achieved higher removal efficiencies for COD, color, and NH(3)-N compared with other studied applications.

Inorganic and organic pollutants continue to pose major problems in receiving water bodies. To overcome such problems, a new composite adsorbent material combining excellent properties of activated carbon, zeolite, and low cost adsorbents, that is, limestone and rice husk ash, was fabricated. The study also determined the capability of the new composite media to remove contaminants from semiaerobic stabilized landfill leachate. The process of identifying the optimum composition of the new adsorbent was carried out using batch technique. Further, isotherm study and regeneration of the media were investigated. Results indicated that there was favorable adsorption by both Langmuir and Freundlich isotherms. However, Langmuir isotherms were slightly better fitted for ammonia, chemical oxygen demand (COD), and color removal in terms of regression coefficients (R2). According to the Langmuir model, adsorption capacity of ammonia, COD, color, and iron reached 37.59 mg/g, 22.99 mg/g, 43.67 Pt-Co/g, and 0....