Petroleum waste biodegradation with porous biomass support system (PBSS) on rotating biological contactor

A laboratory scale study was conducted to assess the feasibility of the new coupling of rotating biological contactor (RBC) plus porous biomass support system (PBSS) using polyurethane foam as porous support media to biodegrade petroleum refinery wastewater. Polyurethane foam was attached on disks of two four-stage laboratory scale cascade connected RBC units.The two RBC units were operated simultaneously at different but constant, flowrates giving hydraulic loading rates of 0.01, 0.02, 0.03, 0.04 m3/m2/d in two runs keeping the same rotational speed 10 r/min throughout. Organic loading was a less controllable factor in this study.For all of the hydraulic loadings, it was found that the removal efficiency of total chemical oxygen demand (TCOD) and oil were above 80 percent. Ammonia nitrogen and phenol removal were above 90 and 80 percent respectively. The maximum biomass concentration within polyurethane foam was about 30 g/m2 in the first stage for 0.03 m3/m2/d hydraulic loading.The results show that t     

Wastewater treatment with multilayer media of waste and natural indigenous materials

Wastewater treatment using waste materials (refuse concrete, waste paper and charcoal) and natural indigenous rocks (andesite, limestone, granite and nitrolite) in the form of multilayer media was investigated. The removal of suspended solids (SS), phosphate ion, nitrate ion, ammonium ion, toxic metals and chemical oxygen demand (COD) were evaluated for the multilayer wastewater treatment system. Effective removal of heavy metals such as cadmium, chromium, mercury and lead was demonstrated. SS and phosphate ion were removed with relatively high efficiency and the COD after treatment was lessened using certain combinations of media. The present wastewater treatment system is simple, convenient and low cost. Therefore, this method can be applied in small scale plants for wastewater treatment in local and nonexclusive areas.     

Traditional water bodies and ecosystem services: Empirical evidence from West Bengal,India

Traditional water harvesting systems are multi-functional in nature and provide a variety of ecosystem services that contribute to the overall wellbeing of local people. This study aims to identify and analyze the factors influencing the variations in the level of awareness across households residing around three selected traditional water bodies in the Indian state of West Bengal. Ordinary least square (OLS) regression models have been used to identify and analyze the determinants of household perception on ecosystem services from tank water bodies. Results show that while a majority of households have strong perceptions on the provisioning and cultural ecosystem services of the tanks, the household perceptions on regulating and supporting services of the tank is found to be relatively weak. Households belonging to lower caste and poor are likely to be more dependent on ecosystem services from tanks than upper caste and rich households, and hence they have better perceptions of provisioning ecosystem services. Households’ awareness about provisioning ecosystem services is negatively related to their level of education and wealth. It is observed that household awareness about regulating and supporting ecosystem services is positively associated with the level of education of the households, ownership of tube well and private tanks. While it is essential to consider household perception on all the ecosystem services for sustainable use and management of traditional water harvesting systems, incorporating the local norms, customs and preferences in policy design are critical for achieving effective conservation outcomes.     

Investigation on the effect of sintering temperature on kaolin hollow fibre membrane for dye filtration

Despite its extraordinary price, ceramic membrane can still be able to surpass polymeric membrane in the applications that require high temperature and pressure conditions, as well as harsh chemical environment. In order to alleviate the high cost of ceramic material that still becomes one of the major factors that contributes to the high production cost of ceramic membrane, various attempts have been made to use low cost ceramic materials as alternatives to well-known expensive ceramic materials such as alumina, silica, and zirconia in the fabrication of ceramic membrane. Thus, local Malaysian kaolin has been chosen as the ceramic material in this study for the preparation of kaolin hollow fibre membrane since it is inexpensive and naturally abundant in Malaysia. Due to the fact that the sintering process plays a prominent role in obtaining the desired morphology, properties, and performances of prepared ceramic membrane, the aim of this work was to study the effect of different sintering temperatures applied (ranging from 1200 to 1500 °C) in the preparation of kaolin hollow fibre membrane via dry/wet phase inversion-based spinning technique and sintering process. The morphology and properties of membrane were then characterised by SEM, AFM, FTIR, XRD, and three-point bending test, while the performances of membrane were investigated by conducting water permeation and Reactive Black 5 (RB5) dye rejection tests. From the experimental results obtained, the sintering temperature of 1400 °C could be selected as the optimum sintering temperature in preparing the kaolin hollow fibre membrane with the dense sponge-like structure of separation layer that resulted in the good mechanical strength of 70 MPa with the appreciable water permeation of 75 L/h m² bar and RB5 rejection of 68%.     

Characterization of titanium oxide optical band gap produced from leachate sludge treatment with titanium tetrachloride

Environmental Science and Pollution Research - This study investigated the coagulation performance of titanium tetrachloride (TiCl4) for leachate treatment and preparation of titanium oxide (TiO2)...     

Does foreign direct investments impair the ecological footprint? New evidence from the panel quantile regression

This study examines the impact of foreign direct investments on ecological footprint along with other explanatory variables of 92 countries from the year 2001 to 2016. Here, we applied the panel quantile regression model to meet the purpose of our study as it considers unobserved country heterogeneity, unlike other statistical methods. The study reveals that foreign direct investment has a positive relationship with the ecological footprint in each quantile except one, which proves the constancy of the pollution haven hypothesis. Moreover, we also tried to detect the impact of economic growth, manufacturing value-added, the percentage of world exports, and institutional quality on the ecological footprint in this study. The findings of this study also reveal that economic growth and manufacturing value-added are negatively associated with the ecological footprint. With respect to the percentage of world exports and institutional quality, we found a positive relationship with the ecological footprint. From the result of our study, different policy implications have been proposed for host countries and foreign investors on improving the economy through foreign direct investment with minimal ecological footprint.

     

Role of UPP pathway in amelioration of diabetes-associated complications

Environmental Science and Pollution Research - Type 2 diabetes (T2D) is one of the most widely spread metabolic disorder also called as “life style” disease. Due to the alarming number...     

Identification of structural breaks in the forest product markets: how sensitive are to changes in the Nordic region?

Forests play a fundamental role in the global carbon cycle and can be managed to mitigate greenhouse gas emissions and conserve or sequester carbon. Global policy and environmental changes can affect regional consumption of forest products, as well as inter-regional trade of forest goods and services. This study analyzes global and regional change impacts on the production, consumption and trade of forest products in two Nordic countries, Finland and Sweden. Annual data on removal and trade (1964–2012) for roundwood and sawnwood is used to identify structural breaks based on Chow tests. According to the analysis, the time period is divided into two periods: t1 (1964–1980) and t2 (1981–2012). In the first period, breaks occurred in 1975 and 1976 in the Finnish model and no break is found in the Swedish model. In the second period, we identify breaks in 1991 and 1992 for the Finnish model and in 2004, 2005 and 2006 for the Swedish model. Although our findings have broad empirical support, we do not identify any specific incident as a direct cause of the changes in the consumption and trade patterns of the two types of wood in these countries. The models and analysis presented here can serve as methodological tools for policymakers to better understand the effects of structural changes in the production of forest goods and services in the Nordic region and globally.