Search results

In fire resistance tests (FRTs) of building materials, a crucial criterion to pass the test procedure is to avoid the leakage of the hot flue gases caused by gaps and cracks occurring due to the thermal exposure. The present study's aim is to calculate the deformation of a steel door, which is embedded within a wall made of bricks, and qualitatively determine the flue gas leakage.

A computational fluid dynamics/finite element method (CFD/FEM) coupling was introduced representing an intermediate approach between a one-way and a full two-way coupling methodology, leading to a simplified two-way coupling (STWC). In contrast to a full two way-coupling, the heat transfer through the steel door was simulated based on a one-way approach. Subsequently, the predicted temperatures at the door from the one-way simulation were used in the following CFD/FEM simulation, where the fluid flow inside and outside the furnace as well as the deformation of the door were calculated simultaneously.

The simulation showed large gaps and flue gas leakage above the door lock and at the upper edge of the door, which was in close accordance to the experiment. Furthermore, it was found that STWC predicted similar deformations compared to the one-way coupling.

Since two-way coupling approaches for fluid/structure interaction in fire research are computationally demanding, the number of studies is low. Only a few are dealing with the flue gas exit from rooms due to destruction of solid components. Thus, the present study is the first two-way approach dealing with flue gas leakage due to gap formation.

In a new build waste incinerator, the waste (refuse derived fuel) was burned on a discontinuous moving grate. Frequent furnace overpressure peaks occurred because of this firing method and as a result, flue gas and fly‐ash were pushed out of the boiler and into the building. During the plant start up period, a seal in a water‐feed pipeline broke, and a large amount of condensed steam was discharged into the boiler house. Shortly thereafter, very severe corrosion was noticed on the galvanised gangways, steel building components, the boiler aluminium sheeting and on processing lines. A theoretical study of the condensation of the flue gas indicated that sulphuric acid would condense before it reached the external aluminium sheeting and that under normal conditions, dry hydrochloric acid fumes would be removed by the boiler house ventilators. However, the steam leakage had caused the hydrochloric acid to be dissolved in the condensed water and that had resulted in the severe corrosion damage, which had become evident subsequently.

Reports on the research and development work carried out at Central Research Laboratories Ltd [CRL], concentrating on their physical and chemical sensing techniques and the manufacture of sensors based on silicon field effect transistors [FETs]. Describes the use of FETs in ion sensitive field effect transistors and gives their advantages over conventional ion selective electrodes, suggesting possible application areas might be in clinical blood analysis, soil sampling and water testing. Also looks at the use of FETs in gas sensitive field effect transistors, which have been used in chicken house atmosphere monitoring and for detecting hydrogen induced cracking in oil and gas pipelines. CRL has also been involved in the development of low cost electro‐chemical gas cells by new manufacturing techniques. Concludes with the range of sensor technologies that CRL has expertise in.

Corrosion failures due to condensing flue gases containing H₂O, SO₃, NO_x and HCl still occur more often than might be expected. The corrosion failures can be of several types: general corrosion, pitting attack and stress corrosion cracking (SCC). The chemistry of condensing gases is discussed, and some examples of corrosion in large‐scale installations are presented, including blast stoves for steel production, heat recovery steam generators, and waste incineration boilers. The use of thermal insulation inside boiler casings can result in nitrate SCC when the flue gas contains high concentrations of NO_x. Nitric acid from flue gas can react with carbon steel and insulation material forming ammonium nitrate and calcium nitrate. Both materials have hygroscopic properties and are very corrosive, even above the water dewpoint of the gases.

In Turkey, dependence on foreign countries for energy is a problem which upsets all economic balances. Turkey’s biggest fossil energy source is lignite coal. Therefore, energy conversion of lignite in thermal plants, causing minimum environmental effect is extremely important. The basic problem in terms of the combustion technology is to improve the combustion technology that can burn the low-qualified fuels that do not have standard fuel features (lignite, peat, schist). The most suitable technology today for the efficient and clean combustion of nonstandard low-qualified fuels is the combustion at fluidized-bed technology. In this study, CO₂ emission that occurs during the combustion of Orhaneli coal that is one of our native low-qualified lignite, has been investigated according to the experimental study.

For this combustion experiment, laboratory-scaled circulating fluidized-bed (CFB) process that exists at TÜBITAK-MAM Energy Institute which has been designed and used before has been used. The effect of excess-air coefficient, combustion type and bed temperature to the greenhouse gas formation and CO₂ emission has been investigated experimentally. In terms of flue gas emissions, it has been detected that the decrease of the amount of CO₂ that has occurred has no positive effects on combustion efficiency, water vapor, SO₂, NO_x, CO and other gases which occur during deficient combustion must be thought as a whole and each reaction affects each other similar to complex reactions.

As a consequence of measuring CO₂ emissions over 10 minute periods, CO₂ emissions are 12.43 percent average, CO₂ decreases at different air coefficient values; Often form undesirable side reactions such as CO, NOx with back and forth reactions.

The importance of aerodynamic structure of the system, and the losses and leakages forming in the system has been observed experimental and affected parameters are evaluated.

Outlines the various causes of chimney defects and considers the process of inspection and the remedial work which may be necessary to prevent problems recurring in the short to medium term. Explores damage caused by weather, fire and problems with linings, and offers solutions to problems caused by the fitting of gas appliances. Details the procedure of an inspection survey, discussing insulation and fitting a liner. Suggests a 48‐hour period following completion of work before a fire is lit.

The purpose of this study is to evaluate the efficiency of a Brazilian steelmaking company’s reheating process of the hot rolling mill.

The research method is a quantitative modeling. The main research techniques are data envelopment analysis, TOBIT regression and simulation supported by artificial neural networks. The model’s input and output variables consist of the average billet weight, number of billets processed in a batch, gas consumption, thermal efficiency, backlog and production yield within a specific period. The analysis spans 20 months.

The key findings include an average current efficiency of 81%, identification of influential variables (average billet weight, billet count and gas consumption) and simulated analysis. Among the simulated scenarios, the most promising achieved an average efficiency of 95% through increased equipment availability and billet size.

Additional favorable simulated scenarios entail the utilization of higher pre-reheating temperatures for cold billets, representing a large amount of savings in gas consumption and a reduction in CO2 emissions.

This study’s primary innovation lies in providing steelmaking practitioners with a systematic approach to evaluating and enhancing the efficiency of reheating processes.

The purpose of this paper is to identify and characterize a geological storage site at more than 800 m depth that is capable of storing large quantities of carbon dioxide (CO₂) in the Alberta Basin and is close to a large CO₂ supply.

Five criteria are used to select the site: total volume of the pore space of the formation for CO₂ (i.e. capacity); accessibility of the pore space in the storage site to CO₂ (i.e. permeability or injectivity); ability of the storage site to retain the CO₂ once the CO₂ has been injected (i.e. containment); protection of other resources from contamination; and cost of the whole process: capture of the CO₂, transport and storage (i.e. economics).

The Heartland Redwater Leduc Reef is identified as a site that has large capacity, good injectivity, and is an excellent trap. Contamination of the oil in the oil reservoir at the top of the reef (the third largest oil reservoir in Canada) is avoided by co‐optimizing CO₂ storage and oil production.

The Heartland Redwater Leduc Reef is ideally located at relatively shallow depth (1,000‐1,200 m), has a large amount of residual oil and is close to large CO₂ sources which make it one of the most economically attractive sites in the Western Canadian Sedimentary Basin.

The Heartland Redwater Leduc Reef Saline Aquifer CO₂ Capture and Geological Storage Project (HARP) is investigating the technical and economic feasibility of injecting significant volumes of CO₂ into the large water‐saturated portion of a huge Devonian reef that is capped by a comparatively small oil reservoir, nevertheless the third largest oil pool in Canada. The reef has a total areal extent of nearly 600 km³, is more than 1,000 m deep and is up to 275 m thick. Based on the high‐water injectivity in the reef, the potential exists to inject sustainably in excess of 1,000 tonnes of CO₂ per day per well in the aquifer portion of the reef. Preliminary storage capacity estimates for the aquifer are in the order of one gigatonne of CO₂. The Heartland Redwater Leduc Reef has the combination of a large oil reservoir sitting on top of a much larger local aquifer. This is a unique site for storage in Canada and could be a model for the rest of the world for carbon dioxide capture and storage.

A systems perspective of waste management allows an integrated approach not only to the five basic functional elements of waste management itself (generation, reduction, collection, recycling, disposal), but to the problems arising at the interfaces with the management of energy, nature conservation, environmental protection, economic factors like unemployment and productivity, etc. This monograph separately describes present practices and the problems to be solved in each of the functional areas of waste management and at the important interfaces. Strategies for more efficient control are then proposed from a systems perspective. Systematic and objective means of solving problems become possible leading to optimal management and a positive contribution to economic development, not least through resource conservation. India is the particular context within which waste generation and management are discussed. In considering waste disposal techniques, special attention is given to sewage and radioactive wastes.

Have you ever looked at a line of pylons marching across the countryside and wondered — how do they get the wires up there? If so, then you should see The Linesmen (b & w, 20 min). This tells of the men who are building the British 400,000 volt super‐grid system. Power like this needs a network of extra tough transmission lines — and extra tough men to build them. In this story, the route is across thirty‐four miles of swamps, bogs and hills in North Wales, to join the Trawsfynydd nuclear power station to the super‐grid.