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C02 Removal
Treatment of the feed gas for removal of carbon dioxide is accomplished with an amine system having a circulation rate of approximately 12.5 m3/hr (55 gpm). The MDEA solvent proposed for this process is INEOS/Gas Spec CS-1160, 50.0 wt% aqueous solution, which is a proprietary activated MDEA solution.
Feed gas enters the gas treating unit at approximately 75 barg and initially flows to 21-V-0101, the Inlet Gas Filter/Separator. The purpose of this vessel is to remove any small liquids and solids entrained in the feed gas. Normally no liquids are present. If any liquid is collected inside this vessel, it is sent to the Slop Drum. The gas then enters the Amine Contactor. Amine solution flowing down through the tower removes CO2 in the feed gas to a concentration of less than 50 ppmv before the gas flows to the dehydration unit. The lean gas leaves the Amine Contactor and flows through 21-E-OI05, the Contactor Outlet Cooler, where the water¬saturated gas is cooled against cooling water to reduce the temperature of the gas going to the dehydration unit. This helps reduce the size ofthe dehydration unit considerably.
CO2-rich amine solution leaves the bottom of21-T-OIOI and flashes into 21-V-OI02, the Amine Flash Drum, at 3.4 barg. The CO2-rich vapor from the flash drum is released to the vent/flare header. The rich amine from 21-V-OI02 is heated in 21-E-OI01, the RichlLean Exchanger, before being fed to the top of the Amine Stripper, 21-T-0102. The RichlLean Exchanger economizes the heating duty and reduces the demand on 21¬E-OI04, the Amine Reboiler.
The Amine Stripper operates at roughly 0.69 barg and employs a water-cooled overhead reflux system. Overhead vapor from 21-T-0102 flows through 21-E-0 102, the Stripper Reflux Condenser, where it partially condenses while being cooled. The two-phase mixture then flows into 21-V-OI03, the Stripper Reflux Drum, where the vapor and liquid phases separate. Vapor from 21-V-OI03 containing CO2 and a hydrocarbon trace are continuously vented to the atmosphere. The Stripper Reflux Pumps, 21-P-0 103A/B, provide reflux for the stripper.
Heating of the amine solution in the Amine Reboiler, 21-E-OI04, generates the stripping vapor in the Amine Stripper. The reboiler heat is provided by steam generated in 21-E-0 106, the Steam Boiler. The Steam Boiler is a closed loop unit producing low pressure steam dedicated solely to providing heat to 21-E-0104. In this way, high skin temperatures which can result from high temperature heating media are avoided. High skin temperatures in the reboiler can cause severe amine degradation. A heating medium is used to produce steam in 21-E-OI06, using heat from the Waste Heat Recovery Unit.
Lean amine from the bottom of the Stripper flows to 21-V-OI04, the Lean Amine Surge Drum, which provides liquid surge volume and allows for reduced volume in the bottom of 21-T-0102. From 21-V-0104, the lean amine is cooled in the RichlLean Exchanger. The lean amine is then pumped by the Amine Booster Pumps, 21-P-OI02A/B, through the Amine Cooler, 21-E-OI03, where it is cooled further by exchange with cooling water and partially filtered in 21-U-OIOllOI02 before being pumped to the top of the Amine Contactor by 21-P-0101AlB, the Amine Circulation Pumps.
去除原气里的二氧化碳这个处理是由胺系统amine system完成的，该系统循环率接近12.5 m3/h(55 gpm)。该项目加工建议乙醇胺MDEA溶剂为INEOS/Gas Spec CS-1160,50 wt%水溶液， 恰好地激活MDEA溶液。
原气进入气体处理装置压力大约为75 barg，最初流进进气滤器/分离器21-V-0101。此分离器的用途是去除原料气里夹带的小晶体和固体。通常不会出现小晶体。如果此分离器搜集到任何小晶体，小晶体被送至污水油罐。随后原料气进入胺接触器Amine Contactor。胺溶液流经该塔去除原料气中的CO2，原料气流至脱水装置之前，浓度需小于50ppmv。贫气离开胺接触器流经21-E-0105，接触器出口冷却器Contactor Outlet Cooler,水饱和气在冷却器中被冷却水冷却减温之后进入脱水装置。以上过程相当程度上减少了脱水装置的规模。
富含CO2的胺溶液离开21-T-0101底部，快速进入21-V-0102，胺闪蒸罐Amine Flash Drum，压力值为3.4barg。来自闪蒸罐的富含CO2的蒸发气体被释放至放空/火炬联箱vent/flare header。而来自21-V-0102的富气在被送至胺气提器Amine Stripper顶部之前，会进入21-E-0101中被加热，贫/富气交换器。贫/富气交换器为21-E-0104胺再沸器Amine Reboiler节省了加热量和减少了热需求。
胺气提器Amine Stripper大致运行压力为0.69 barg并且采用了一个水冷塔顶回流系统water-cooled overhead reflux system。来自21-T-0102塔顶蒸发气流经21-E-0102胺气提器回流冷凝器Stripper Reflux Condenser，部分气体在此浓缩和冷却。随后双相混合气体流进21-V-0103，胺气提器回流罐stripper Reflux Drum，回流罐的用途是把蒸发和液态双相分离。来自21-V-0103饱含CO2和烃持续排放进大气。胺气提器回流泵21-P-0103A/B为胺气提器提供回流。
在胺再沸器里21-E-0104加热胺溶液，在胺气提器里产生气提蒸汽stripping vapor。再沸器里的热量是是由蒸汽锅炉Steam Boiler产生的蒸汽提供的。该蒸汽锅炉为闭合环里装置产出低压蒸汽，只供热给21-E-0104。由此，可避免因高温加热煤质引起的外壳高温high skin temperatures。再沸器外壳高温可导致严重的胺降级。在21-E0106里有一个加热媒介凭借来自废热恢复装置Waste Heat Recovery Unit里热能产生蒸汽。
来自胺气提器底部的贫胺液流入21-V-0104，贫胺液缓冲罐Lean Amine Surge Drum，缓冲罐为21-T-0102底部提供液体缓冲量并允许减少量。从21-V-0104，贫胺在贫富胺液换热器里被冷却。贫胺液由胺增压泵21-P-0102A/B抽送，流经胺冷却器21-E-0103，在冷却器里经过与冷却水的热交换进一步冷却，部分贫胺液由胺循环泵21-P-0101A/B抽送至胺接触器顶部之前，在21-U-0101/0102被过滤。
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发表于 2013-5-28 19:44
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