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Combustion in a furnace equipped with two HiTAC burner pairs, with a thermal power of 100kW(th) each, has been investigated experimentally and computationally. The objective of this study is (1) to observe differences in the performance of the furnace operating in two different firing modes, parallel and staggered, and (2) to explain these differences using detailed CFD simulations. Besides the permanent measurements of temperature, flow and pressure, in-furnace probe measurements of temperature, oxygen and emissions (NO and CO) have been performed. Experimental results show that the efficiency of the furnace was higher in parallel mode compared to staggered mode, 48% and 41% respectively. The values of CO emitted were equal for both firing modes. However, in parallel mode the NOx production was 39 ppm(v)@3%O-2, whereas in staggered mode 53 ppm(v)@3%O-2 NOx was produced. Considering both efficiency and emissions, parallel firing mode performs better than staggered mode. Next, CFD simulations of the furnace were performed in order to explain the observed differences. The simulations were validated with the in-furnace measurements. It was confirmed that the furnace firing in parallel mode achieved a higher efficiency. The radiative heat transfer was higher due to formation of a larger zone with gases with improved radiative properties. In addition, higher velocities along the cooling tubes, due to lower momentum destruction, led to higher convective heat transfer. Also, the lower production of NOx in parallel mode was reproduced by the simulations. This is due to the fact that in parallel mode the fuel jets are merging slower with the combustion air jet, leading to less intense combustion zones. Thus, lower peak temperatures and radical concentrations are achieved, and the NOx production via the thermal and N2O pathways was lower., QC 20110418

A new carbon capture and recycle (CCR) system based on multi-reforming of CH4 with CO2 is proposed in this study. The aim was to develop a novel method to remediate greenhouse gases (CO2) using a high temperature (over 1173 K) process of reforming CH4 and/or O2, and/or H2O without catalysts. Using this novel method, the reactants are individually preheated to over 1173 K using a ceramic honeycomb heat exchanger, and then these high temperature streams enter the reactor to start the reforming reactions. Both thermodynamic and experimental studies were carried out on this novel method. Thermodynamic equilibrium models were built for four types of reforming, including dry reforming, bi-reforming, auto-thermal reforming, and tri-reforming. Only dry reforming was experimentally tested. The feasibility of this novel technology was proven by simulated and experimental results. High temperatures significantly promoted the multi-reforming process while avoiding the problem of catalyst deactivation. The experimental results on the direct system also showed that potential improvements in the efficiency of the novel technology could be achieved by optimizing the reforming reactants. Therefore, a continuous system was proposed. Moreover, the power source for the application of CCR systems was also discussed., QC 20131025

Exploitation of olive kernel for bioenergy production, with respect to the green house gases (GHGs) mitigation, is the main aim of this work. In this study, olive kernels were used as a solid biofuel, and high temperature steam gasification (HTSG) was investigated, in the fixed bed unit at KTH Sweden, with regard to hydrogen maximization in the produced gasification gas. Experiments were carried out in a temperature range of 750-1050 degrees C, with steam as the gasifying agent. The behaviour of olive kernels, under residence times from 120 up to 960 s, has been studied. At 1050 degrees C, a medium to high calorific value gas was obtained (LHVgas = 13.62 MJ/Nm(3)). while an acquired H-2/CO molar ratio equal to four proved that olive kernel HTSG gasification could be an effective technology for a hydrogen-rich gas production (similar to 40%vv H-2 in the produced gasification gas at 1050 degrees C). The produced char contained 79%ww of fixed carbon, low chlorine and sulphur content, which enables it for further re-use for energetic purposes. Tar content in the produced gas at 750 degrees C was 124.07 g/Nm(3), while a 1050 degrees C at 79.64% reduction was observed and reached the value of 25.26 g/Nm(3)., QC 20100525

QC 20120110

Due to the increased manufacturing of new vehicles, older ones the so called end-of-life vehicle's (ELV) are being disposed more frequently. The EU ELV directive (entered into force 21/10/2000) sets targets and objectives that must be obeyed by the member states. Under this directive from 01/01/2006 for all ELV, the reuse and recovery rate should be min. 85% (by weight) and min. 80% (by weight) rate of recycling. From 01/01/2015 for all ELV, the reuse and recovery rate should be min. 95% (by weight) and min. 85% (by weight) rate of recycling. Because of the lack of a cost-effective technology to recycle this waste, it is mostly land filled, smaller amounts are incinerated. In this work, basing on the reviewing of the available technological methods, a new thermal treat system for ASR is proposed: Firstly, a microwave pyrolysis of ASR is used. During this pyrolysis process, metals will be successfully recycled, and also generate by-products such as pyrolysis gas, oil, and char. These by-products will be further reformed using high-temperature steam gasification to generate high-purity synthetic gas, which will be used for a small-scale electricity generation system. Energy and mass balance of the whole system will be done. The electricity generation efficiency will be assessed., QC 20141021

Car industry and also another producer consume spend huge amount of electric cables. After end of life equipment this is a source of nonferrous metals and electric cable shredders. This paper presents experiment study on high quality synthetic gas produce from plastic cables isolation shredders take advance of high temperature gasification. Experimental results of laboratory scale batch type gasification reactor are presented. Small amount of samples was inserted to process agent like mixture of oxygen (1% vol.) with nitrogen and just in to pure steam. Tests were repeated in different temperatures up to 1323K. Base on this experiments mass balance, composition and heating value of gas was calculate. Moreover tars composition was investigate. All the cases with gasification agents and different temperatures were repeated with different duration time and mass loss ratio were draw. High temperature of the process gives strong impact on hydrogen production and tar decomposition. Pure steam gasification significantly improves gas heating value and reduce tar amount in gas., QC 20141021