Malaysia is considered as a major palm oil producer in the world. Therefore, it is vital to utilize an environmentally friendly and inexpensive method to treat palm oil mill effluent (POME) in Malaysia. Nowadays, the use of microalgae to remove pollutants from POME has gained a lot of attention. The main objective of this research was to investigate the effect of POME as a nutrient on the microalgae growth and analyze the removal rate of pollution. In this study, a pure culture Chlamydomonas incerta was aseptically transferred to an Erlenmeyer flask containing POME. The effect of POME as a high nutritional substrate, different cultivation scales, carbon total nitrogen (C:TN) ratio, and the lipid productivity of microalgae C. incerta were assessed. C. incerta was grown at room temperature under continuous illumination with the intensity of ± 15 (μmol/m2/s) for 28 days, followed by the measurement of chemical oxygen demand (COD) reduction at different substrate concentrations. The results of this study demonstrated that organic carbon was removed by C. incerta for the ratio of 100:7, 100:13, and 100:31 respectively within the second day of cultivation. Fast growth of microalgae was observed in organic and inorganic substrates for adoption within the second day of experiment. The optimum achievement rate of nutrient removal with C. incerta was about 67.35% of COD for 250mg/L of POME concentrations in 28 days. The significance of this study is regarding the introduction of a new microalgae strain with a high ability to remove nutrients from POME, which can contribute to the effort in finding an efficient and economic technology for improving our environment
Oil and gas construction projects are complex and risky because of their dynamic environment. Furthermore, rising global energy demand has increased the need for trustworthy risk assessment models for such projects that can provide adequate and precise policy planning. Traditional risk assessments in oil and gas construction projects do not consider the interrelationships of factors in the best-fit models. The Decision Making Trial and Evaluation Laboratory (DEMATEL) and Analytic Network Processes (ANP), called the DEMATEL-ANP approach, have been applied to other research disciplines to address this shortcoming. This method is able to construct a structural relationship among the different influence factors to visualize complex correlations. Thus, the purpose of this study is to showcase the DEMTAL-ANP risk assessment model to assess the overall risk factors of OGC projects. This study thus identifies the crucial risk criteria of such projects. Data were collected in 2016 through interviews with experts active in OGC projects in Iran. DEMATEL in this situation is used to determine the interdependencies’ relative strengths among the risks. The ANP method is applied to assess the relative importance of the risk factors and to determine the best strategy for implementation of a risk management program. The results presented in this study are a novel adaptation of the risk assessment methodology to OGC projects that determines the important risk factors that directly affect the project success, which in turn helps in formulation of policies for ensuring reliable energy supply planning.
1 November 2014 in Renewable and Sustainable Energy Reviews