Fauziah Shahul Hamid

Drivers of sustainable waste management in Asia

Drivers of sustainable waste management are defined as groups of related factors that influence the development (or lack thereof) of industry. There has been no attempt to reasonably list the drivers that influence sustainable waste management in Asia. In this review, four groups of drivers of sustainable waste management, specifically of Asia, are explained. The four groups of drivers consist of three human elements (human, economic and institutional) and the environment as a single driving group. Typically, the first three groups have been very influential, with the environment driver, noticeably, only considered when preceded by other groups of drivers. The interconnectedness of the drivers and neglect of the environment driver is discussed. It is concluded that while the essence of the four groups of drivers can be found all over Asia, each driving group must be investigated in a local context and all information combined to devise sustainable waste management policies or strategies.

VERMICOMPOSTING OF TWO TYPES OF COCONUT WASTES EMPLOYING EUDRILUS EUGENIAE: A COMPARATIVE STUDY

BackgroundWhile the increase in the number of coconut-based industries in Malaysia supports economic growth positively, it affects the environment negatively by generating large amounts of coconut wastes. This study has endeavored to assess the possibility of vermicomposting different types of coconut wastes and, in doing so, evaluated the potential of using the African nightcrawler (Eudrilus eugeniae) to decompose coconut wastes. The study was conducted over a 50-day duration using two different types of coconut wastes: coconut husk (CH) and spent coconut flakes (SCF). The nutrient content of the vermicompost at various stages of treatments was determined. Three different percentage ratios were used: {C1-W or B1-W (100% waste), C2-W or B2-W (70% waste  +  30% goat manure), and C3-W or B3-W (50% waste  +  50% goat manure)}. Twenty healthy adult E. eugeniae (each 0.02 to 0.03 kg) were introduced to each treatment.ResultsResults showed that the degradation process was very fast in the spent coconut flakes which needed only 16 days for complete decomposition, while that in the coconut husk needed 2 months. Available phosphorous (P) and total potassium (TK) values declined in CH. The available P and TK in C3-W (50% waste  +  50% goat manure) were less than the initial values by 26.6% and 53.69%, respectively. Moreover, P and TK values increased in SCF at the final stage as in B2-W (70% waste  +  30% goat manure) which was 69.3% more than the initial level. The weights of the worms were recorded throughout the experimental period.ConclusionsThe study showed that vermicomposting could be an efficient method to convert coconut wastes into a valuable by-product.

Removal of organic matter from stabilized landfill leachate using Coagulation-Flocculation-Fenton coupled with activated charcoal adsorption:

The treatment of stabilized landfill leachate (SLL) by conventional biological treatment is often inefficient due to the presence of bio-recalcitrant substances. In this study, the feasibility of coagulation-flocculation coupled with the Fenton reaction in the treatment of SLL was evaluated. The efficiency of the selected treatment methods was evaluated through total organic carbon (TOC) removal from SLL. With ferric chloride as the coagulant, coagulation-flocculation was found to achieve the highest TOC removal of 71% at pH 6. Then, the pretreated SLL was subjected to the Fenton reaction. Nearly 50% of TOC removal was achieved when the reaction was carried out at pH 3, H2O2:Fe2+ ratio of 20:1, H2O2 dosage of 240 mM and 1 h of reaction time. By coupling the coagulation-flocculation with the Fenton reaction, the removal of TOC, COD (chemical oxygen demand) and turbidity of SLL were 85%, 84% and 100%, respectively. The ecotoxicity study performed using zebrafish revealed that 96 h LC50 for raw SLL was 1.40% (v/v). After coagulation-flocculation, the LC50 of the pretreated SLL was increased to 25.44%. However, after the Fenton reaction, the LC50 of the treated SLL was found to decrease to 10.96% due to the presence of H2O2 residue. In this study, H2O2 residue was removed using powdered activated charcoal. This method increased the LC50 of treated effluent to 34.48% and the removal of TOC and COD was further increased to 90%. This finding demonstrated that the combination of the selected treatment methods can be an efficient treatment method for SLL.

Assessment of Natural Radioactivity Levels and Radiation Hazards in Agricultural and Virgin Soil in the State of Kedah, North of Malaysia

The activity concentrations of naturally occurring radionuclides 226Ra, 232Th, and 40K were determined in 30 agricultural and virgin soil samples randomly collected from Kedah, north of Malaysia, at a fertile soil depth of 0–30 cm. Gamma-ray spectrometry was applied using high-purity germanium (HPGe) gamma-ray detector and a PC-based MCA. The mean radioactivity concentrations of 226Ra, 232Th, and 40K were found to be 102.08 ± 3.96, 133.96 ± 2.92, and 325.87 ± 9.83 Bq kg−1, respectively, in agricultural soils and 65.24 ± 2.00, 83.39 ± 2.27, and 136.98 ± 9.76 Bq kg−1, respectively, in virgin soils. The radioactivity concentrations in agricultural soils are higher than those in virgin soils and compared with those reported in other countries. The mean values of radium equivalent activity (Raeq), absorbed dose rates D (nGy h−1), annual effective dose equivalent, and external hazard index (H ex) are 458.785 Bq kg−1, 141.62 nGy h−1, and 0.169 mSv y−1, respectively, in agricultural soils and 214.293 Bq kg−1, 87.47 nGy h−1, and 0.106 mSv y−1, respectively, in virgin soils, with average H ex of 0.525. Results were discussed and compared with those reported in similar studies and with internationally recommended values.

Disaster Waste Management Challenges

Disasters are brought about by various causes such as earthquakes, tsunamis, typhoons, volcanic eruptions, fire, terrorism, war, and negligence. Over the past decade, several major disasters have destroyed social infrastructure all over the world: the Sumatra–Andaman earthquake in 2004, Hurricane Katrina in 2005, the Great Sichuan Earthquake in 2008, and the earthquakes in New Zealand and Turkey in 2011. The Great East Japan disaster started with a magnitude 9.0 earthquake offshore from the Sanriku region on 11 March 2011, the most severe ever observed in Japan, with at least 100 000 buildings totally or partially destroyed. Similar to the devastation in Japan, significant damage was caused to the city of Christchurch and the central Canterbury region when New Zealand was impacted with 6.3 magnitude earthquake in February 2011. Having the building structures weakened with the February 2011 earthquakes, a series of aftershocks of 5.3 and 6.3 magnitudes in June 2011 resulted with huge damage, reportedly as the third costliest earthquake in the world history. Massive flooding in late July 2011 onwards was the worst flood experienced in Thailand in 50 years (http://en.wikipedia.org/wiki/2011_Thailand_floods). The damage is estimated to be more than US

Stabilized landfill leachate treatment by coagulation-flocculation coupled with UV-based sulfate radical oxidation process

45 billion, with a huge amount of debris generated. Depending on a disaster’s causes, the types of industry in the locality, the density of buildings, and other such factors, there are considerable differences in the quality and geographical extent of the environmental and waste collection/disposal problems that arise. Waste management issues include the availability of disposal capacity, availability of treatment, recycling and reuse options, transportation of waste materials, accessibility to waste management facilities, environmental hazards, financial implications, labour availability, and legal and ethical responsibilities. All these and more aspects need to be considered by those responsible for planning and conducting clean-up and waste management strategies. As for the categories of waste generated from disaster events, the applicable strategies vary greatly. In other words, there are big differences in the nature of the environmental impacts and the types of waste resulting from individual disasters, thus generalisation is difficult. The following is one of many conceivable classification schemes for the composition of disaster wastes from earthquakes and tsunamis: waste consumer electric appliances and electronics, and various household effects; waste wood, concrete rubble, tiles, etc.; plants, trees, and other natural items; large structures, etc.; deposits (silt, bottom sediment, etc.); wrecked vehicles and boats; hazardous wastes (asbestos, pesticides, polychlorinated biphenyls, radioactive material, etc.); evacuation centre waste; and infectious waste (human corpses and animal carcasses). The waste management strategies consider how wastes could be recycled so that valuable resources can be reused and scarce landfill space conserved. The 2004 tsunami in Sri Lanka reportedly produced approximately 0.6 million metric tons of waste. The disposals begun with open burning and were eventually stopped due to air pollution. Then, the practice changed to burying of waste in existing dumpsites, coral mining areas and even playgrounds. Thailand, on the other hand had to deal with more than 0.9 million metric tons of disaster waste during and after the 2004 tsunami event incurring a total cost of approximately US

Environmental Evaluation of Sanitary Landfills Establishment: Malaysian Case Studies

30 billion. Construction and demolition debris generated during and after the earthquake and tsunami in 2004 that hit Banda Aceh, Indonesia, required use of more than 725 000 m3 of land for disposal. In these and other areas, such as in Japan, lack of sufficient close-by land area suitable for debris disposal presents substantial challenges. Yet, benefiting lessons can be learnt from these events. A report released by the Japanese government estimated that the Great East Japan Earthquake generated approximately 28 million metric tons of disaster waste, which is equal to the total solid waste generated in one year by the local population (http:// www.recwet.t.u-tokyo.ac.jp/kurisu/gs11s/report2.html). The amount is likely to exceed 44 million metric tons if tsunami sediment deposits are included. The contamination of the waste with radioactive emissions complicated the waste collection and disposal. Although some have criticised the slow response to disaster debris collection and disposal, it is apparent that clean-up following an earthquake and tsunami presents even greater challenges than those faced by crews responding to an earthquake alone, such as the Great Hanshin Earthquake situation. Although the damage from the Great Hanshin Earthquake was huge, the collapsed houses, buildings, and other structures remained essentially in their original places; thus the efforts of each property owner can be marshalled to help deal with his own clean-up and debris removal. On the contrary, in the Great East Japan Earthquake, it was only in rare cases that private property remained at its original location. Thus, it has been difficult if not impossible to even contact the rightful owners of debris let alone enlist their help in the cleanup. Additionally, Tohoku region has fewer established disposal sites compared to that of Kobe region where the largest disposal site in Japan was located. A week after the Great East Japan Earthquake, the Japan Society of Material Cycles and Waste Management (JSMCWM), Disaster waste management challenges 434630WMR

Evolution of solid waste management in Malaysia: impacts and implications of the solid waste bill, 2007

In this work, the feasibility of coagulation-flocculation coupled with UV-based sulfate radical oxidation process (UV/SRAOP) in the removal of chemical oxygen demand (COD) of stabilized landfill leachate (SLL) was evaluated. For coagulation-flocculation, ferric chloride (FeCl3) was used as the coagulant. The effect of initial pH of SLL and COD:FeCl3 ratio on the COD removal was evaluated. The result revealed that COD:FeCl3 ratio of 1:1.3 effectively removed 76.9% of COD at pH 6. The pre-treated SLL was then subjected to UV/SRAOP treatment. For UV/SRAOP, the sulfate radical (SR) was generated using UV-activated persulfate (UV/PS) and peroxymonosulfate (UV/PMS). The dosage of oxidant and reaction time were found to be the main parameters that influence the efficiency of COD removal. On the other hand, the effect of initial pH (3-7) and the type of oxidant (PS and PMS) was found to have no significant influence on COD removal efficiency. At optimum conditions, approximately 90.9 and 91.5% of COD was successfully removed by coagulation-flocculation coupled with UV/PS and UV/PMS system, respectively. Ecotoxicity study using zebrafish showed a reduction in toxicity of SLL from 10.1 to 1.74 toxicity unit (TU) after coagulation-flocculation. The TU remained unchanged after UV/PS treatment but slightly increased to 1.80 after UV/PMS treatment due to the presence of residual sulfate ion in the treated effluent. In general, it can be concluded that coagulation-flocculation coupled with UV/SRAOP could be a potential water treatment method for SLL treatment.

Immobilization of Pb, Cd and Zn in a contaminated soil using eggshell and banana stem amendments: metal leachability and a sequential extraction study

Poor management of dump-sites creates significant risks to environment and human health. Thus, sanitary landfills are required to be more effective to minimize the impacts of waste disposal. This research assesses the environmental economic evaluation focused on the economically efficiency of Malaysian sanitary landfills. Two landfills were selected based on their different operation. Landfill A incurred RM 128 million (USD 41.8 million) as the total cost within 20 operational period. Thus, it is estimated that the cost may be covered within 15 operational years. On the other hand, the total costs for Landfill B are estimated at RM 198 million (USD 64.8 million) with RM 245 million (USD 80.2 million) are expected to be obtained as profit within eight operational years. Landfill B has high initial costs of design and construction. However, the costs are covered within the first five years. This is because Landfill B introduces a new green technology namely landfill-gas power generator. This indicates that, Landfill B has stronger market competition ability as compared to Landfill A. It can be concluded that the implementation of green technology namely landfill gas harvesting system has higher impact to improve the economic value of a landfill thus making it more economical and environmentally sustainable.