Experimental Studies on Continuous Electrocoagulation Treatment of Peat Water in Sarawak with Copper Electrodes

Abstract: Electrocoagulation is an electrochemical wastewater treatment method, which coagulates impurities particles and ions by using electrical current. In Sarawak, freshwater peat covers around 1.698 million hectares whereas the other 154,000 hectares are mangrove. Peat water is the water or moisture produced from these peatland or peat soil. Clean water availability in the rural coastal regions is limited due to the high financial cost of distribution of essential clean water resources to sparse population in the remote areas. Therefore, a cost-effective standalone electrocoagulation system for the treatment of peat water in Sarawak is one of the suggested solutions to this water supply problem. The main aim of this research is to develop a continuous electrocoagulation water treatment system by using copper electrodes to treat peat water in Sarawak. The peat water treated is targeted to achieve at least standard quality for domestic usage and the parameters studied to measure the optimal design of the treatment system are the turbidity, total suspended solids (TSS), total organic carbon (TOC), pH and chemical oxygen demand (COD) of the water treated. The experimental results meet the standard for Raw Water Quality and Drinking Water Quality with an optimum parameter of 20 electrodes, 0.7 cm inter electrodes spacing, current density of 5.99A/m2 and treatment time of 100 minutes. The total operating cost for the optimize parameters is RM 0.11 per litre of peat water. Overall, the treatment of peat water by using continuous electrocoagulation with copper electrodes is feasible. &nbsp

Experimental study of batch electrocoagulation treatment of peat water in Sarawak with aluminium electrodes

Peat water is commonly found in the coastal areas of Southern and Central Sarawak. About 39% of the rural communities in Sarawak are yet to receive clean water supply. As such the rural communities depend excessively rainwater and peat water for domestic usage. However, the usage of untreated peat water for domestic usage may cause harm to human health and well-being as it contains natural organic matters such as humic substances. Electrocoagulation is an environmentally friendly and simple process of water treatment. This research aims to develop a batch electrocoagulation process for treatment of peat water in Sarawak using Aluminium electrodes. The research includes the study on electrocoagulation for peat water treatment, design, and fabrication of batch electrocoagulation process using Aluminium, experimental study for optimum performances of the electrocoagulation, and economic analysis of the electrocoagulation system. Several parameters that affect the performances of the electrocoagulation system are studied such as the inter-electrode distance, number of electrodes, current density and treatment time. The performance of the system is evaluated based on the removal efficiency on turbidity, colour, Chemical Oxygen Demand (COD), Total Organic Content (TOC) and Total Suspended Solid (TSS). The system successfully removes 100% of colour, 93.35% of turbidity, 89.80% of COD, 88.22% of TOC, and 87.50% of TSS by using a current density of 25 A/m2 in 80 minutes and 8 Aluminium electrodes with inter electrode spacing of 2 cm. The final quality of treated peat water is determined to be suitable for domestic usage which falls under Class 1 water of the National Water Quality based on the parameters analyzed. The operating cost of 25 A/m2 current density for 80 minutes of treatment time by using 8 electrode plates is RM 4.32 per m3 of peat water

Development of solar power system for Sarawak peat water continuous electrocoagulation treatment process

Sarawak state government has established Sarawak Alternative Rural Water Supply (SAWAS) programme in order to serve as a purpose of providing safe and clean water to the rural communities not connected to municipal clean water supply. In the rural areas of Sarawak, particularly on the coastal region where municipal water supply is not available, the villagers are normally resorted to utilize rainwater and peat water for daily usage. Some of these rural areas are even not connected to electricity grid. Subsequently, one of the proposed methods to eradicate these problems in supplying clean water without electricity supply grid is to implement stand-alone water treatment system with solar power system. As such, the main aim of the study is to design a solar power system to support Sarawak peat water electrocoagulation treatment process. The study is divided into two stages. In the first stage, the study designs a solar power system to support the treatment process of peat water for both batch and continuous electrocoagulation systems. This includes designing and fabrication of a small-scale solar power system. The second stage of the study involved experimental studies on both batch and continuous electrocoagulation systems in order to study the effectiveness of solar power system to supply electricity for the electrocoagulation systems. Overall, the study has developed a solar power system for both batch and continuous electrocoagulation of peat water system. From the experiments conducted, the developed systems are capable to reduce 18.8% and 46.15% of peat water turbidity for batch and continuous electrocoagulation systems respectively. However, in order to meet a more stringent drinking water standards, some improvements on the designed systems are indispensable

Adsorption of fatty acid on beta-cyclodextrin functionalized cellulose nanofiber

Fatty acids in wastewater contribute to high chemical oxygen demand. The use of cellulose nanofiber (CNF) to adsorb the fatty acids is limited by its strong internal hydrogen bonding. This study aims to functionalize CNF with β-cyclodextrin (β-CD) and elucidate the adsorption behaviour which is yet to be explored. β-CD functionalized CNF (CNF/β-CD) was achieved by crosslinking of β-CD and citric acid. Functionalization using 7% (w/v) β-CD and 8% (w/v) citric acid enhanced mechanical properties by increasing its thermal decomposition. CNF/β-CD was more efficient in removing palmitic acid, showcased by double adsorption capacity of CNF/β-CD (33.14% removal) compared to CNF (15.62% removal). CNF/β-CD maintained its adsorption performance after five cycles compared to CNF, which reduced significantly after two cycles. At 25 °C, the adsorption reached equilibrium after 60 min, following a pseudo-second-order kinetic model. The intraparticle diffusion model suggested chemical adsorption and intraparticle interaction as the controlling steps in the adsorption process. The maximum adsorption capacity was 8349.23 mg g−1 and 10485.38 mg g−1 according to the Sips and Langmuir isotherm model, respectively. The adsorption was described as monolayer and endothermic, and it involved both a physisorption and chemisorption process. This is the first study to describe the adsorption behaviour of palmitic acid onto CNF/β-CD

KINECTIC STUDY & STATISTICAL MODELLING OF SARAWAK PEAT WATER ELECTROCOAGULATION SYSTEM

Penduduk di kawasan pedalaman di Sarawak terpaksa menggunakan air gambut sebagai kegunaan harian kerana bekalan air tidak mencukupi. Penggunaan air gambut yang tidak dirawat boleh membawa kepada pelbagai penyakit air seperti cirit-birit, dan penyakit serius lain seperti kepialu dan disentri. Oleh itu, sistem rawatan air seperti sistem elektrokoagulasi dapat dibangunkan untuk meningkatkan mutu air gambut supaya dapat digunapakai oleh penduduk di pedalaman. Sistem elektrokoagulasi dipilih kerana tidak ada penggunaan koagulan kimia, hanya memerlukan peralatan yang dapat dioperasikan dengan mudah, dan kos yang efektif. Tujuan utama kajian ini adalah untuk membangunkan kajian kinetik dan model statistik untuk proses electrokoagulasi rawatan air gambut di Sarawak. Fokus kajian ini adalah kepada rawatan air gambut menggunakan sistem electrokoagulasi. Sistem electrokoagulasi direka mengikut beberapa kriteria iaitu teknologi untuk pembinaan dan bahan yang digunakan untuk membina sistem electrokoagulasi mudah diperoleh, pembuatan yang mudah serta kos rendah untuk pembinaan dan operasi. Untuk kajian ini, Response Surface Methodology dalam perisian Minitab dan Microsoft Excel digunakan untuk kajian kinetik, model statistik, dan pengoptimuman proses. Pengoptimuman proses dijalankan untuk meminimumkan penggunaan tenaga dan kekeruhan air gambut. Keadaan optimum bagi sistem elektrokoagulasi kelompok adalah 14.899 A/m2 dan 41.818 minit dan sistem elektrokoagulasi terus adalah pada 3.861 A/m2 dan 37.778 minit

Adsorption of Fatty Acid on Beta-Cyclodextrin Functionalized Cellulose Nanofiber

Fatty acids in wastewater contribute to high chemical oxygen demand. The use of cellulose nanofiber (CNF) to adsorb the fatty acids is limited by its strong internal hydrogen bonding. This study aims to functionalize CNF with β-cyclodextrin (β-CD) and elucidate the adsorption behaviour which is yet to be explored. β-CD functionalized CNF (CNF/β-CD) was achieved by crosslinking of β-CD and citric acid. Functionalization using 7% (w/v) β-CD and 8% (w/v) citric acid enhanced mechanical properties by increasing its thermal decomposition. CNF/β-CD was more efficient in removing palmitic acid, showcased by double adsorption capacity of CNF/β-CD (33.14% removal) compared to CNF (15.62% removal). CNF/β-CD maintained its adsorption performance after five cycles compared to CNF, which reduced significantly after two cycles. At 25 °C, the adsorption reached equilibrium after 60 min, following a pseudo-second-order kinetic model. The intraparticle diffusion model suggested chemical adsorption and intraparticle interaction as the controlling steps in the adsorption process. The maximum adsorption capacity was 8349.23 mg g−1 and 10485.38 mg g−1 according to the Sips and Langmuir isotherm model, respectively. The adsorption was described as monolayer and endothermic, and it involved both a physisorption and chemisorption process. This is the first study to describe the adsorption behaviour of palmitic acid onto CNF/β-CD