Page 1 of 2 cracked gas compressor query posted in chemical process simulation. This can be due to leaking interstage seals or compressor freeradical polymer fouling on the compressor blades and diffuser typically the 2. Compressor wash oil new fracturing and drilling technologies are continuously increasing the shale gas capacity, offering both opportunities and challenges to the ethylene industry. The consequences of this fouling can be seen in reduced efficiency, increased vibrations, higher. This article describes the basic design and operation of these compressors. Compressor rotor failure due to fouling turbomachinery. The mechanical engineers who design the centrifugal compressors within ethylene plants are often disconnected from the process engineers who specify the pressure. This is a controllable loss, but the decision to wash fouled blades to gain energy efficiency or to stop vibration must be an informed.
Since hydrogen is consumed by the chemical reactions, a makeup compressor supplies additional hydrogen to the loop. The process of ethane gas cracking was the sole reason of compressor fouling. The cracked gas compressor cgc is the critical system in modern. The path to improved cracked gas compressor performance. Polymer deposits on compressor internals which increases frictional losses and alters flow pattern. Most ethanepropane crackers employ a fourstage cracked gas compressor, interstage coolers, knockout drums, acid gas removal system, dehydrators, and frontend hydrogenation systems. Actual compressor perform ance monitoring of deviation in design and actual efficiency. Fouling will reduce compressor efficiency, as it makes the wheels less smooth. Several attempts have been carried out to solve this process in ethylene plants, but reducing fouling and energy costs during naphtha cracking remains a. This fouling degrades the performance of the compressor, which reduces throughput or increases power consumption. This rising availability has the potential to reduce operational costs but goes hand in hand with fouling issues and an increased need for compressor wash oils. Organic fouling in process gas compressors pgc is an important issue that.
Dec 19, 2006 wet gas compressor fouling posted in industrial professionals. Olefins plant cracked gas compressor fouling tutorial aiche. During the production, coking can adversely affect the manufacturing performance, such that furnaces have to be decoked for some controlled time. A long awaited economical route from natural gas to chemical base feedstock. Several attempts have been carried out to solve this process in ethylene plants, but reducing fouling and energy costs during naphtha cracking remains a challenge. Cracked gas from the furnaces is compressed by the charge gas compressor. The naphtha cracking process experiences problems such as fouling in the cracked gas compressor, and the accumulation of coke on the furnace coils, which require the use of exhaustive energy resources and costs to maintain the process. Customer is doing wash oil at 2 percent rate continuously and wash water with batch mode only. Our experience in crack gas applications allows flexibility in engineering compressor and driver configurations. Gas compressor rerate and process solutions through. Wet gas compressor fouling industrial professionals. For example, in ethylene cracked gas compression, fouling results from the polymerization reactions intrinsic to the compression process. Olefins plant cracked gas compressors frequently foul, resulting in loss of efficiency that increases energy consumption, and may threaten operational reliability, and ultimately cause throughput limitations.
Gas turbine compressor blade fouling mechanisms pipeline. Fouling of compressor blades is an important mechanism leading to performance deterioration in gas turbines over time. The high potential for severe fouling leads to deterioration of plant performance with associated significant economic penalties in energy and productivity losses. The challenge an ethylene plants most critical pieces of equipment are its cracked gas compressor and turbine. Cracked gas compressor query chemical process simulation. In petrochemical compressors, the situation is much more complicated, as the foulants can be generated internally.
Train performance evaluation and monitoring by torque. Usually, the washing media is injected into the suction pipe line and return bend of each stage to wash the fouling. The inevitable compressor blade fouling by the crackedgas process leads to a blade imbalance that causes excess vibration and compressor trip. Cracking furnace system is the starting and the most critical sector of an ethylene plant where heavier components are cracked into lighter products, such as ethylene, propylene, and etc. I guess that this material is product of polymerization of olefins in wet gas stream. Wash oil optimum flow rate calculation in hysys simulator. Acrylonitrile the total benefit was a % reduction of energy consumption at the first stage of the cracked gas compressor. Compressor endusers and oems have gone a long way to cope with fouling and corrosion.
A common example is a multistage crackedgas compressor a threestage compressor on the process flow diagram may have as many as 12 compressor stages. The management of reactor resources has a over 240 of cumulative experience in onsite sulfiding services, hydroprocessing catalysts, and. Sulfiding services, reactor resources provides turnkey catalyst sulfiding services, including the supply and delivery of sulfur chemicals, rental of injection equipment, and speciallytrained technicians to set up and operate our pumps and analyzers. Fouling can occur in the machine itself, interstage coolers, knockout drums, or associated piping. In the early days, petrochemical companies frequently shutdown their units in order to clean out the foul and restore the efficiency. Agree this is more of a process technology related question. Adequate wash oil selection and antifoulant injection enables cracker extension of cracked gas compressor run lengths by reducing the amount of polymer fouling. Improve compressor reliability with advanced chemical. Both lp and hp sections are affected lp section to a lesser extent. Multistage centrifugal compressor fouling evaluation at high. There is data available in open literature for typical rates. It discusses the challenges specific to crackedgas and refrigeration compressors used in ethylene plants.
Dear all,what are the experiences in wet gas compressor fouling. There were occasions where the compressor impellers were cracked due to fatigue as identified by metallurgical analyses performed. For example, in ethylene manufacturing industry, cracked gas compressors used to be shutdown. Olefins plant cracked gas compressors frequently foul, resulting in loss of efficiency that increases energy consumption, and may threaten. Pivot cracked gas compressor fouling project digitized the performance curve of compressor applied correlation testing and association rule mining to gain insights from the data developed an algorithm to evaluate over 36 billion combinations of operating parameters developed a dashboard to show daily analyzed data using r shiny. Initial efficiency loss does not increase costs significantly if there is adequate turbine capacity. The cracked gas compressor treats the hydrocarboncontaining gases such as mixtures containing acetylene, and they induce the adherence of fouling on the compressor flow path. We had a 5 stage centrifugal, 50 kpa suction to about 4000 kpa discharge with interstage cooling. The cracked gas contains trace amounts of compounds that can polymerize within the gas stream and stick to the flow path in the compressor. March 2010 cracked gas compressors blade fouling also causes energy efficiency losses as great as 1%. Centrifugal compressors are used in ethylene plants for crackedgas compression and refrigeration services. From that point, the cracked gas went through a caustic scrubber to remove traces of co2 before it was dried we used mol sieves and started down the cold train and then the. Gas from the scrubber enters the inlet of the recycle compressor.
Overview of cracked gas compressor fouling theories and. Seal or impeller failure, excess vibration, shaft cracks. Maximizing steam turbinecompressor performance with precise. The control variables that can lead to blade fouling. Optimize and protect cracked gas compressors with smart. From the enduser perspective the fouling of axial compressor is a continuous problem. It is widely known that there is a potential for fouling in cracked gas compressors within ethylene plants. The fouling adversely affects compressor performance resulting in reduced plant throughput and increased power consumption. Secondly, also want to know if polytropic efficiency of compressor is alone good indicator of fouling as efficiency is a function of temp and pressure ratios and gas composition also. Initial efficiency loss does not increase costs significantly if there is adequate turbine.
Train performance evaluation and monitoring by torque meter. Although this simplified compressor has three process stages, it has four compressor stages. The degradation was slow initially but accelerated with time, and the compressor efficiency dropped from 65% new to 35% failure. Note the wash oil will ultimately end up in your pygas stream. Typical wash oil injection rates for the compressor will be function of compressor throughput, type of fouling expected based on gasliquidmixed feed cracking. We could supply any oil and gas field compressor with a very rich experience. A torquemonitoring system was recently installed on a cracked gas compressor train at qenos olefins in australia to determine the causes of a power limitation. Enhance cracked gas compressor reliability with novel antifoulant. Pdf on nov 4, 2018, visagaran visvalingam presenter and others published ethylene unit cracked gas compressor case studies on fouling find, read and cite all the research you need on researchgate. The torque meter is now being used to monitor turbine steam fouling issues and process related compressor fouling so that the corrective online washing can be activated as soon as issues arise.
Apr 04, 2019 550052 olefins plant cracked gas compressor fouling tutorial thursday, april 4, 2019. Figure 1 typical crack gas compressor mitsubishi in addition to downtime, there can also be production losses due to the crack gas compressor operating inefficiently over a long period of time. Cracked gas compressor challenges difficult to control steam during startup fouling of blades and related washing reduces throughput instrument drift creates potential for surge or wasted energy from rec ycling too much gas trip causes flaring and product loss excess vibration that can shut downtrip the compressor risk of surge from reducing. Gas crackers have generally had a higher fouling potential than liquid crackers due to the lack of aromatic gasoline formed in the cracking process. Optimize crackedgas compressors with smartautomation. Recently weve learned that many ac or heating systems are being diagnosed as unrepairable due to compressor failure or a cracked heat exchanger, but before you invest in a new air conditioning or heating system, its important to make sure you are making the right decision and that the problem. Ethylene unit cracked gas compressor case studies on fouling. The customer is experiencing severe fouling of a cracked gas compressor. A torquemonitoring system was recently installed on a crackedgas compressor train at qenos olefins in australia to determine the causes of a power limitation. Blade fouling also causes energy efficiency losses as great. Compressor strings can include two to four compressor bodies in addition to the specified driver. The failures on the centrifugal gas compressors were mainly associated with fouling and resonance.
The present invention relates to wash oil for use as an antifouling agent in gas compressors, in particular in cracked gas compressors, comprising at least one compound according to formulae ii wherein the moieties r 2 and r 3 are selected from a group comprising linear or branched c 1 c 20 alkyl, c 3 c 10 cycloalkyl and linear or branched c 1 c 10 alkyl substituted c 3 c 10. A sudden, and unexpected, expense can cause stress, and raise red flags for nearly all of us. The dominance of ethane as a cracking feedstock for ethylene. Wash oil should remove part of that fouling, but there is no way that you can calculate that effect. This key equipment performance susceptibility to fouling has been studied in this paper. Wet gas compressor fouling posted in industrial professionals. There are a lot of options available to the operator for monitoring, servicing and treating the cracked gas compressor. Gas turbine compressor blade fouling mechanisms fouling of compressor blades is an important mechanism leading to performance deterioration in gas turbines over time. Fouling imposes significant costs on petrochemical production.
The cracked gas compressor is one of the most critical piece of equipment in an ethylene plant and may be the limiting factor in ethylene plant performance optimization. Modeling and computation of fouling of a 36mw multistage. Fouling in a cracked gas compressor can negatively affect plant economics. I hv calculated wash oil and wash water requirement for cgc in ethylene plant. Cracked gas compressor fouling, which results from polymerization and saturated heavy hydrocarbons in olefins plant, remains one of the leading factors responsible for decreasing ethylene production revenues. In this session we will discuss the various options to help the unit engineer understand the benefits and limitations of each. The 108 ethylene plants polled in the survey, which are responsible for 62% of the worlds production, named compressor fouling as the second most frequent cause for compressor failure. This paper provides a comprehensive practical treatment of the causes, effects, and control of fouling. Jul 27, 2017 the air conditioning unit uses the compressor and refrigerant sometimes referred to as freon to remove the heat from the air. Yi xiang lim data science executive petronas linkedin. Fouling high gas recycle rates reduce energy waste and optimize antisurge valve use by leveraging re liable, realtime intelligence about asset health and your process. Process considerations for cracked gas compressor selection.
Development of anti fouling type coatings for centrifugal. Maximizing steam turbinecompressor performance with. Cracked gas stream being compressed contains diolefutic compounds. Wo2016083290a1 wash oil for use as an antifouling agent in. The compressor is basically a large electric pump that pressurizes the refrigerant gas, turning it back into a liquid. Improving ethylene charge gas compressor performance aiche. Effect of steam and carbon dioxide on naphtha cracking to. Our fcc unit employes turbine driven centrifugal compressor that suffers from severe build up of polymerization material on the rotor parts. Comptrene reduces inter cooling fouling in ethylene.
The effect of compressor fouling is a drop in airflow, pressure ratio, and compressor efficiency, resulting in a rematching of the gas turbine and compressor and a drop in power output and thermal efficiency. The key role of the addition of steam is the fractional elimination of the accumulated coke that leads to various issues within the reactor, such as the. This presentation covers ethylene unit cracked gas compressor case studies on fouling. The cracked gas compressor is a multisection centrifugal compressor, with 4 or 5 stages of compression required to bring the cracked gas pressure up to the desired value of approx. The gas from the final separator flows to a hydrogen sulfide h 2 s scrubber where liquid amines are used to remove the h 2 s from the recycle gas. Olefins plant cracker gas compressor fouling digital refining. The cracked gas compressor is usually driven by an extraction type steam turbine, using high pressure live steam and extracting steam to the plants medium. Optimize crackedgas compressors with smartautomation technology. Compressor wash oil impact on process gas compressor efficiency. I hv naphtha cracker wherein there is an issue of fouling. I hv naphtha cracker wherein there is an issue of fouling in cracked gas compressor and its intercoolers also.