Sharif Digital Repository

According to the World Bank, nearly 154 billion cubic meters of gas is flared in the world every year. Iran is known as the third gas flaring country by burning about 11.4 bcm (approximately 8% of the total amount). Flared gas is a rich gas and has a high heating value. Therefore flaring it equals to waste of a valuable source of energy. In addition, serious concerns about its environmental effects due to emission of considerable amounts of CO2, SOx, NOx and other pollutants, makes it necessary to find a solution to reduce gas flaring. There are several ways for flared gas utilization including electricity generation, injecting into oil wells for enhanced oil recovery, gas processing and... 

Different methods can be used to produce reduction gas. One example is using coal. But today there’s a tendency to use natural gas. One way of transforming natural gas to reduction gas is to burn it with gases produced by combustion, such as or vapor; usually a catalyst is used in this method. Another method is burning natural gas directly with oxygen or air. The recent method is of benefit especially in Iran, because of available natural gas resources and avoiding catalyst problems. Designing a burner for this purpose is an important step in reaching this goal. In this project such a burner is designed and manufactured. The burner manufactured in this project burns natural gas with... 

The need for planning for the management and recovery of flare gases is an important issue in the energy sector of the country. On a day, about 46 million cubic meters of gas in Iran is burning in the torch, which in addition to the destruction of non-renewable energies, contributes to environmental pollution and emissions of greenhouse gases. Gas burning is one of the few pollutant activities that is due to short-term economic revenues, system design weaknesses, and lack of management in the operation process, with no service provided or value added. Iran is ranked third in the world according to satellite data among the countries that are burning flares. Accordingly, by burning 17/7... 

Ethylene process is one of the most complex systems in petrochemical industries.The first section of the ethylene plant is the cracking furnace.The radiant section of predicted olefin furnaces is symmetrical with respect to a plane through the center line of the furnace and at an angle of 90° with the side walls. There are a total of 24 vertical radiant coils located centrally in the firebox wherein, bottom andside wall burners supply the heat necessary. Each four coils known as a ZONE so, as a result there are six zones, called zone A through F. Failures(rapture, creep, material degradation) rate on the coils decreases from zone A to zone F (A, B, C, D, E and F) respectively.From... 

By combustion, waste toxic, flammable and corrosive materials are changed to less inviromental problems by combustion. It also creats environmental problems (the most serios problem is caused by burning gases), as well as economic resources are wasted. So several ways was investigated to reduce combustion gases. Mini-methanol plant is one of varios possible ways that can convert these gases in to methanol. So methanol plant was simulated and then pinch analysis was performed on the simulated plant. Performing of pinch analysis caused 94.5 percent and 25 percent reduction in amaunt of hot and cold utility respectively. Before and after pinch analysis, the exergy analysis was performed on... 

In recent decade, pollution reduction is one of challenges in front of engineers. Nowadays accurate prediction of temperature and harmful Pollutants is vital, this leads to various models for turbulent combustion to predict combustion-generated pollutants. One of the most widely used models for simulating turbulent combustion is Flamelet because of separating the chemical reactions and the turbulent flow field. The unsteady state assumption of Flamelet model is capable of reasonably predict complicated phenomenon such as slow chemical reaction and radiation. The purpose of this study is to calculate combustion-generated emissions by Flamelet model and reduce these emissions by engineering... 

The main application of flares is to protect facilities, staff, and surrounding area. Nevertheless, the flares flue gas contains environmental hazardous compounds like nitrogen oxides, sulfur oxides, and greenhouse gases like carbon dioxide and carbon monoxide. These compounds may spread in environment with unburned hydrocarbons. Due to the contamination risk and energy loss in flaring system, optimization and system enhancement is of vital importance. Flare gas recovery unit consist of equipment like multi-phase separator, Liquid Seal Drum, and compressor. The compressor is the most important part of this unit. Due to the process requirements and the probability of two-phase feed entering... 

The Increasing trend of gas flaring over oil fields and gas process systems in Iran not only causes several environmental problems, but makes the economical resources useless as well. Considering the high amount of flaring and old facilities, one of the best solutions is the recovery of the flare gas in Iran. It seems that collecting the flare gas is not possible in different sectors. Therefore, using a plant for converting flare gas to other products must be logical. In this project, the feasibility study of converting flare gas to other products is studied. For this reason, a methanol plant is simulated; whose input feed is the content of flare gas of the South of Iran (Marun and Siri).... 

Inappropriate performance of the air-cooled condensers in the process industry will make the flow out of the air cooler not fully condensate and its pressure is greater than the design value. This will lead to product loss and safety issues. In this study, factors affecting the performance of air cooler and various solutions to solve these problems have been identified. As a case study, the first distillation tower of the Ali Siana Petrochemical Complex, which disrupts its function in some months of the year, has been investigated. Aspen Hysys process simulation software simulates the naphtha splitter unit and the Aspen Exchangers Design & Rating software simulates the air cooled condesor... 

Incereasing trend of energy consumtion and limited sources of conventional energy carriers causes an increase of carrier’s price and as a result nowdays more attention is focused on unconventional energy carriers. One of these unconventional carries is flare gas, which has a high potentioal for recovery.There are different methods for flare recovery and electricity generation is one of the most economic solutions for flare gas. The purpose of this project is technical and economical investigation of electricity generation using flare gas and to study impact of important parameters on economy of design. Reciprocationg engin, gas turbine and steam turbine are chosen for investigation. Capital... 

In the current study, the dispersion of four major air pollutants, sulphur dioxide, nitrogen oxide, carbon monoxide, and particulate matter from gas flares of an oil field, in Iran, was investigated for year 2011 by application of a conventional steady state Gaussian dispersion model, AERMOD. Two scenarios were applied in modeling, first application of flare parameters based on technologies that exist and the other one using new technologies in flares such as steam assisted with better combustion efficiency. Due to the complexity of meteorological parameters in modeling area, CALPUFF model was used in this study. CALPUFF which is a more advanced model that considers the effect of... 

Using of physical safety devices such as pressure safety valves, are the most conventional methods to protect vessels against overpressure but operation of these devices have many negative effect on environment also they waste significant amount of valuable hydrocarbon materials. Relying on conventional safety devices needs a flare net to send excess gas to torch and in many cases essential equipments for flare net is so expensive and their maintenance are difficult thus reducing the size of flare net for a chemical plant is beneficial.
Application of new alternative device (HIPPS) is very helpful to reduce flaring load and releasing pollutant materials such as SOx and NOx. The main... 

The HIPS is a safety integrity system that is designed to provide overpressure protection that is at least equivalent in reliability to a mechanical relief device. In this study, the performance evaluation of HIPS in Assaluyeh gas Refiner is studied.In the first stage, over pressure analysis is compiled using dynamic simulation and API RP 520 and the recommended HPPS design procedure is presented. Also, The High Integrity Protection Systems (HIPS) further reduced the relief load and even eliminated the relief from the stabilizer tower for the scenarios tested.In this project, following a detailed study of the commissioning process and its criticalities, Hazop is selected as the most suitable... 

Overpressure protection and flare loading network are critical challenges faced by the Oil & Gas and chemical industries. Whether they are new facilities or aging ones, integrity management of overpressure and flaring systems remain significant throughout the life of the planet. One of the most important ways for protection of over pressure and depressurizing to flare header through pressure safety valve is implementation of safety instrument system (SIS). Application of safety instrumented systems for the process industries causes significant reduction of flaring load and loss prevention of valuable materials through increase protection layer availability and over pressure risk reduction....