Performance of a powdered activated carbon [PAC] augmented activated sludge process treating semi- aerobic leachate

Semi-aerobic leachate is characterized by organic matter [COD, BOD] which is relatively low in concentration and difficult to biodegrade. In conventional treatment systems, the low biodegradability is attributed to partial stabilization of leachate at the landfill. Biological treatment of leachate in Malaysia is not well established and any important data for the treatment process is not available. The behavior of microbes is unknown for semi aerobic leachate. This research was conducted to establish some of the important data in the biological treatment of semi-aerobic leachate with and without the influence of powdered activated carbon [PAC]. For the present study, semi aerobic leachate was collected from Pulau Burung andfill Site [PBLS], Nibong Tebal, Penang, Malaysia. The experiment involved operating two 16 L laboratory-scale activated sludge reactors in parallel at room temperature and adjusted to pH of 6.5 +/- 0.5. One of the reactors was supplemented with powdered activated carbon [PAC] of 75-150 micro m size to observe its effect on leachate biodegradation. The results showed enhanced reactor performance due to PAC addition COD, NH[4]- N, NO[3]-N, TKN, BOD and colour removals was higher

Applying the heat integration in order to environmental pollutants minimization in distillation columns

Due to the close relationship between the energy and environmental problems, recovering technology and optimizing energy consumption have a major role in environment protection by minimization the atmospheric pollutants such as SO[x], CO[x], NO[x]. This minimization may decrease the greenhouse effect, and the ozone layer destruction. On the other hand, optimization of Energy consumption and its recovering may minimize the water and hot oil consumption at the heat exchangers [reboilers and condensers] in petroleum distillation columns, specially. The present research has been performed about the kerosene pre-fractionation unit of one of the country's oil refineries. This system includes two distillation columns with a simple arrangement. Considering that the distillation section consumes a great deal of energy in the chemical and petroleum industries, hence studying the ways in which we may decrease this consumption is of great importance. One of these retrofit solutions is the heat integration, which is going to be presented in this research with a different idea from the other previous methods. This method makes it possible to add a shell and tube heat exchanger for performing a part of condensation and evaporation operation which can decrease the heat duties of reboilers and one of the condensers. To this end, the distillation columns were studied in the process and then the proposed model of columns arrangement were simulated by heat integration with all input and output streams using the Aspen Plus software, version 11.1 and the Rad Frac model in this software. The result has showed itself as a save of 14.26%, 10.86% and 14.26% in energy, water and hot oil consumption, respectively. On the other hand this system will decrease emission of SO[2] and CO[2] to atmosphere, 28 kg/h and 837 kg/h, respectively