Contaminants in amine gas treating by randy haws ccr technologies inc. Gas sweetening is the process for the removal of mainly acid gases h 2 s and co 2 and, in addition, the simultaneous removal of sulphur organic species rsh, cos, cs 2 from process gas. Thus, sour gas or acid gas must be treated to remove these toxic components. In order to achieve such speci cations, the raw gas must pass through a series of puri cation steps, which compose the socalled natural gas chain.
The basic flow scheme for an amine sweetening unit is shown in figure 1. Schlumberger designs and manufactures a variety of gas sweetening systems, including amine systems, to remove hydrogen sulfide h2s, carbon dioxide co2, mercaptans, and other contaminants from natural gas streams. Ngl2 adip unit for utility gas sweetening of umm said. The secondary objective is to select the amine which optimizes equipment size and minimizes plant operating costs. Natural gas containing high quantities of h2s and co2 is considered toxic. The sweet gas is removed overhead and the rich amine is drained and. Filters for the natural gas industry parker hannifin. The facility receives offshoreproduced gas with low water 15c and hydrocarbon dewpoints 5c, to be checked, and a. Video sample from amine sweetening, overview and explanation of principles, supported with onsite viewing and clear graphics. Gas sweetening is a critical procedure in gas processing facilities. Pdf gas sweetening process subhasish mitra academia. The shell claus off gas treating scot process catalytically converts the remaining sulphur dioxide in claus tail gas to hydrogen sulphide.
The acid gas removal unit equipment provided by air liquide consists of skid mounted packages and stand alone vessels to condition 170 mmscfd of natural gas using tsa adsorbents regenerated by a hot oil system and then to reduce the co. Typical process flow sheet for amine absorption unit prepared in 58. Pdf a technical report on gas sweetening system researchgate. The first commercial amine applications began in the 1920s. The lpg unit feed streams in a refinery are usually obtained from refinery units such as atmospheric crude distillation, plat former, hydro cracker, and other catalytic processing units. Removal of these acid gases is essential since their presence poses severe corrosion problem to the downstream process lines and. The engineer may not have control over some variables such as inlet gas flow rate and composition. The processes used for removal of acid gas are referred to as sour gas sweetening, amine gas sweetening. This stage is directed more to co2 removal since the bolivian natural gas contains no sulfur in. Selecting amines for sweetening units bryan research.
Rules of thumb in amine sweetening unit design and operation. First, co2 and h2s removal stage which is constructed to assure that co2 would not exceed 50 ppm in the natural gas feed. The sulphur removal process from natural gas is based on adsorption with activated carbon which can remove the last few milligrams of h2s with natural gas flow rates of over 500 000 nm 3 h. Natural gas processing encyclopedia of life support systems. Final selection is ultimately base d on process economics. Sulfinol entrainment in gas sweetening unit posted in refining, hydrocarbons, oil, and gas. An overview natural gas processing and the removal of various components from it tend to involve the most complex and expensive processes. Throughout the following pages the factors that influence sweetening technology selection will be addressed. The different gas sweetening processes to be applied depend on the quality and quantity of acid gas contaminants to be removed. Our expertise in sweetening processes includes multicomponent absorption of inorganic and organic sulphur species. As an illustration of design calculations for a sweetening unit.
Two key passages are the sweetening removal of h 2s and co 2 and the dehydration processes. I do not own this song, all credit and rights goes to the band and the writers. Crude oil sweetening and stabilization aong website. Natural gas is fed into a contactor tower where it contacts the amine. The treated gas exits the unit at a higher temperature than the feed gas. Acid gas loading in amine solutions for natural gas. Lpg is also produced in gas fractionation units charged by associated gas from oil reservoirs or gas from gas reservoirs. Each case must be considered on an individual basis due to a wide range of conditions and requirements for gas processing units. In a natural gas treatment facility, a process referred to as sweetening occurs in which amines are used to remove acid gas mainly hydrogen sulfide and carbon dioxide from inlet gas streams. Conventional merox for sweetening jet fuel or kerosene. Semilean solution enters the top of the bulk section of the bulk of the co2 removal takes place. It can increase pressure drop in the line and often leads to corrosion problems. Lng dehydrationdrying of natural gas absorption and refrigeration with hydrate inhibition is the most common dehydration process used to meet pipeline sales specifications.
Hydrogen sulfide h2s, carbon dioxide co2, mercaptans, and other contaminants are often found in natural gas streams. Moreover, the objective of each sweetening unit may. Simulation of gas treating plant in this work, a process simulator was used to predict the performance of an iranian gas sweetening plant with a sour gas feed containing 1. The mercaptan oxidation reaction takes place in an alkaline environment as the feedstock jet fuel or kerosene, mixed with compressed air, flows through a fixed bed of catalyst in a reactor vessel. Equipment design and cost estimation for small modular. In the transmission of natural gas further condensation of water is problematic. Effect of temperature on the solubility of h 2 s in 4. It is an essential step of sour gas processing for natural gas treatment, ngl recovery.
The co2 is removed from the process gas stream in twostage co2 absorber. Gas sweetening units risk assessment using hazop procedure. This implies that the treated gas water content will be higher than the feed gas water content. H2s form acidic gas ability to selectively no no yes b. Tea type of amine primary secondary tertiary troublesome components in produced natural gas solution strengthin water, include. Using proven amine technology and fulfilling the requirements of our clients, frames gas sweetening is a reliable and costeffective solution that increases the value of gas. Khurmal sour gas is considered a highly loaded acid gas with more than 50,000 ppm of h2s and more than 4 % of co2 and successfully treated the problem by using latest version of aspen hysys v. Before entering the absorber, the gas is passed inlet gas through an inlet separator where entrained droplets knockout or slugs of liquid are removed from the gas stream by impaction devices, figure 2. Gas sweetening is sometimes referred to as amine treating.
Modelling of natural gas sweetening and dehydration processes. Operators of integrated gasification combined cycle igcc units operating on. The absorber overhead gas enters ko drum, where any entrained solution is separated out. Process systems designs, manufactures and installs gas sweetening units either by adsorption with activated carbon or by absorption with amine solution.
Gas sweetening is a process that has to be executed to remove hydrogen sulphide h2s from gasses. Custom and standard amine gas sweetening systems remove co 2 and h 2 s, resulting in gas with gas suitable for transportation and use the amine plant can be installed as a standalone component or as a part of an integrated processing system. The separation of the hydrocarbons, known as ngl c2 plus is carried out next. Amine gas treating, also known as amine scrubbing, gas sweetening and acid gas removal, refers to a group of processes that use aqueous solutions of various alkylamines commonly referred to simply as amines to remove hydrogen sulfide h 2 s and carbon dioxide co 2 from gases. If h2s and co2 volumes are appreciable, this lowers the heating value of the sales gas. Tegi t i b ti tteg is most common in absorption systems meg is most common in glycol injection systems. Amine sweetening units have been used in gas processing for nearly 80 years to remove h2s and co2 from sour gas streams. Amine treating can be used in refineries, petrochemical plants, natural gas processing plants and other industries. Hydrogen sulphide is then stripped from the tail gas and reprocessed. Sour gas must be sweetened because h 2 s and co 2 have a corrosive effect on gas. The conventional merox process for the removal of mercaptans i.
Product definition frames amine systems efficiently sweeten gas by removing hydrogen sulfide, andor carbon dioxide. Sulfinol entrainment in gas sweetening unit refining. Should the feed gas be at high temperature, an inlet cooler using air or water would be required. If the composition of co2 exceeded that limit it would freeze in the liquefaction process pipelines. It is a common unit process used in refineries, and is also used in petrochemical plants, natural gas processing. Hi all, i have some operational problems in a gas treatment plant, and i am trying to figure out where should i look into in order to solve them. L l mea, l dea the slt circulation rate m3h q g the nat gas flow rate std m3h x a the required reduction in total acid gas fraction moles acid gas removedmole inlet gas. In that context, the sweetening unit plays a leading role due to the wide variety of technologies for. Amine treating, or sweetening, is the most widely used method of removing co2 and h2s. The process is referred to as sweetening and it processes gases so they no longer have the sour, foul odors of mercaptans and hydrogen sulphide.
Hazard evaluation of gas sweetening units natural gas is supplied to this plant. Natural gas sweetening process simulation and optimization. In the design of the process, the primary concern is that the sweetened gas meet the. In the design of the process, the primary concern is that the sweetened gas meet the required purity specifications with respect to h 2s and co 2. Acid gas loading in amine solutions is an important factor in operating a gas sweetening unit. Process design of gas treating units project standards and specifications page 2 of 29 rev.
Gas sweetening units, also known as amine treating units, are a processing unit that removes contaminants from gas, making it environmentally suitable for transportation and commercial use. Untreated natural gas containing carbon dioxide c0 2 and hydrogen sulfide h 2 s flows into the bottom of the amine contactor where it contacts countercurrent flowing aminewater from the top of the tower. The amine solution sweetens the natural gas by absorbing the c0 2 and h 2 s upon contact. All of the h2s and most of the water vapor, co2, and n2 must be removed first. To meet sales specifications and maintain efficient operations, natural gas goes through a sweetening process to remove contaminants. Opero energys amine units utilize both generic amine solutions and proprietaryformulated solvents to treat either gas or ngl streams to required levels. In the case of sweetening, the most common process technique. Gas treating age unit claus unit tgt unit acid gas injection. Sebastine2 1school of chemical and petroleum engineering, koya university, kurdistan regioniraq 2school of science and engineering, teesside university, uk abstract natural gas is the most important and. Co2 h2s and co2 absorbed acid gas loading, molemole the amines 0.
652 139 736 902 702 1146 164 695 313 184 1332 518 242 520 674 524 1260 803 310 1007 434 1465 709 739 77 1315 362 338 1346 186 456 208 1014 1116 648 568 460