There are three main types of engine combustion. All three types of engine combustion convert the chemical potential energy found in the fuel to mechanical kinetic energy. The combustion cycle and fuel type required to complete this task are what distinguish the three engine types from each other. Two-stroke cycle engines or two-cycle engines complete their combustion cycle in two piston strokes that are accomplished with one revolution of the crankshaft. The two strokes are the power and compression strokes. The two-stroke engine is unique because it does not control the release of exhaust or the admission of an air/fuel mixture into the cylinder with a traditional valve arrangement, one intake and one exhaust. As shown in Figure 1, the process of filling the cylinder with an air/fuel mixture and exhausting the burned gases occurs almost simultaneously near the end of the power stroke. As the piston moves downward during the power stroke, first the exhaust port is uncovered and then the intake port is uncovered.
Natural gas is the feedstock used in most of the world's production of methanol. Methanol is a primary liquid petrochemical made from renewable and nonrenewable fossil fuels containing carbon and hydrogen. Containing one carbon atom, methanol is the simplest alcohol. It is a colorless, tasteless liquid and is commonly known as "wood alcohol." Stranded gas can be monetized by producing chemical (or fuel grade) methanol and transporting it to the market.
Converting gas to liquids (GTL) through the Fischer-Tropsch (FT) route to monetize stranded gas has received increasing attention over the past few years. FT technology is a process that rearranges carbon and hydrogen molecules in a manner that produces a liquid, heavier hydrocarbon molecule. In general, GTL through the FT route refers to technology for the conversion of natural gas to liquid; however, GTL is a generic term applicable to any hydrocarbon feedstock. This page focuses on GTL processes based on natural gas feedstock. FT chemistry originated during the early 1920s from the pioneering work of Franz Fischer and Hans Tropsch at the Kaiser Wilhelm Inst.
Several techniques are available for minimizing sand production from wells. The choices range from simple changes in operating practices to expensive completions, such as sand consolidation or gravel packing. The sand control method selected depends on site-specific conditions, operating practices and economic considerations. This page introduces the available approaches to sand control. Maintenance and workover is a passive approach to sand control. This method basically involves tolerating the sand production and dealing with its effects, if and when necessary. Such an approach requires bailing, washing, and cleaning of surface facilities routinely to maintain well productivity. It can be successful in specific formations and operating environments.
There are two primary sources of gas: associated gas reserves and nonassociated gas reserves. The economic drivers for monetizing gas from these two basic sources are quite different and are likely to lead to different gas utilization routes. Hence, it is useful to understand the difference in economic characteristics of these two broad categories of gas sources. Nonassociated gas reserves are developed primarily to produce natural gas. There may or may not be condensate production together with the gas. Under these conditions, it is essential that there be a profitable market to which to deliver the gas. Associated gas is gas produced as a byproduct of the production of crude oil. Associated gas reserves are typically developed for the production of crude oil, which pays for the field development costs. The reserves typically produce at peak levels for a few years and then decline. Associated gas is generally regarded as an undesirable byproduct, which is either reinjected, flared, or vented. The need to produce oil and dispose of natural gas (as is the case with associated gas) requires unique approaches in the field-development plans. With increasing focus on sustainable development, flaring may cease to be an option. Some countries have already legislated against gas flaring. For example, current Nigerian policy requires all flaring to be eliminated by 2008. This policy is expected to eliminate the waste of a valuable resource for Nigeria and attendant negative impacts on the environment. Consequently, several key gas utilization projects have either been recently completed or are at various stages of implementation in Nigeria. Examples of such projects include the Obite Gas Plant, ChevronTexaco Escravos GTL project, West African gas pipeline project, and the Nigeria liquefied natural gas (LNG) project. Natural gas reserves are plentiful around the world, but many are too small or too remote from sizable population centers to be developed economically. Estimates of remote or stranded gas reserves range from 40 to 60% of the world's proven gas reserves.
Natural gas is of little value unless it can be brought from the wellhead to the customer, who may be several thousand kilometers from the source. Because natural gas is relatively low in energy content per unit volume, it is expensive to transport. The cost to transport energy in the form of gas is significantly greater than for oil. This is one of the key hurdles to the increased use of gas. The most popular way to move gas from the source to the consumer is through pipelines.
Natural gas is a key source of fertilizers in the form of ammonia and urea. Ammonia is the second largest chemical product produced in the world, behind sulfuric acid. The demand for ammonia is driven by the demand for fertilizers. Of the world's nitrogen demand, 85% is for fertilizer primarily derived from ammonia in the form of: Other uses of ammonia include fibers, resins, refrigeration, and pulp and paper industries. Ammonia can be produced from different hydrocarbon feedstocks such as natural gas, coal, and oil.
Excess anthropogenic CO2 emissions are a global environmental issue and a matter of concern for gas production in the Gulf of Thailand (GoT). The aim of this study is to develop a catalyst that can be used to convert CO2 obtained from a CO2 removal membrane by the cycloaddition reaction of CO2 to epoxides leading to industrially attractive cyclic carbonates. The results show that by using a suitable catalytic system, the reaction can be carried out in high yields under mild condition (Temperature range 25-120 °C and pressure range 4-9 barg). The conversion rate is 98 – 100% under optimized conditions.
Heavy crude oil production in world over is increasing gradually, resulting in higher atmospheric residue yield. Main product qualities such as high sulfur content, metals (Ni, V) & Conradson Carbon Residue (CCR) content in heavy crude & its distillation products pose challenges to refinery operation. Kuwait Integrated Petroleum Industries Company (KIPIC) has Al-Zour Refinery (ZOR) which is designed to process a wide range of crudes; 30 to 14 API such as Kuwait Export Crude (KEC), Kuwait Heavy Crude (KHC), Eocene and Lower Fars for supplying LSFO to power plants and marketing highquality products) for export as per international specifications. ZOR Complex has the world's largest Atmospheric Residue Desulfurization (ARD) units, which is the heart of Al-Zour Refinery. ZOR Project today is in advanced stage of Detailed Engineering, Procurement and Construction (EPC) phase. This paper addresses the features and challenges experienced during the design of residue hydro-treating facilities for heavy oil processing in ZOR and especially ARD with respect to environmental and economic considerations. The road map of this paper starts by apprising its preliminary studies (external agencies studies & licensor pilot test), and challenges in developing a responsive design changes in the project in line with strategy of crude production plan to meet the objective of processing different types of heavy crude in KUWAIT.