May 2020 | Case Study | Amine Plant
Employees: Over 11,000
Industry: Oil & Gas
Project Type: Amine Plant
Project Goal: Readying natural gas for pipeline quality with subsequent CO2 sequestration
Equipment Type: Regenerative Thermal Oxidizer
Gulf Coast Environmental Systems was tasked with find a pollution control solution for an Amine Plant, that would treat Carbon Dioxide (CO2) vent emissions.
This customer is one of the biggest energy infrastructure providers in North America. They own and operate over 100 terminals, and tens of thousands of miles of pipeline. These terminals and pipelines store and transport petroleum products, chemicals, and CO2, among other things. Their customer portfolio includes some of the world’s largest oil producers, shippers, and distribution companies. They are a leader in enhanced oil recovery projects in the US using CO2 collected underground and in their own Amine plants.
Gulf Coast Environmental Systems has provided a number of pollution control solutions for this energy company’s Amine plants over the years. Amine plants present a specific pollution control challenge with potential formation of SO2 with entering H2S, and other sulfuric compounds. Amine plants, like this one, remove CO2 and H2S from natural gas, using several alkanolamines, also referred to as amines. This process, also called gas sweetening or amine scrubbing, is a common process among refineries and natural gas processing plants.
After reviewing this customer’s conditions and requirements, GCES’ engineers determined that a 3-canister Regenerative Thermal Oxidizer was the best solution available. This unit was made of stainless steel and able to meet a 99% Destruction Removal Efficiency (DRE). This solution was designed to achieve a lower than maximum 90% heat recovery due to potential high VOC concentration by installing a blend of ceramic media. Using a natural gas fired burner to withstand an expected operating temperature of 1,500°F, the life of equipment in this solution is expected to be upwards of 25 years with proper care or maintenance.
The method of reduction of Volatile Organic Compounds in a Regenerative Thermal Oxidizer revolves around thermal oxidation. The chemical process of thermal oxidation is quite simple; the exhaust stream temperature is raised to a point that the chemical bonds that hold the volatile organic molecules together are broken. The VOCs in this process exhaust stream are converted to carbon dioxide, H2O, and thermal energy by the high temperature of the combustion chamber.
Through this process, the RTO converts the pollutants in the stream into carbon dioxide and water vapor, all while recovering thermal energy that could be used to reduce the cost of operating the equipment. The process in which this is accomplished is very similar to that of a two-canister RTO. The exhaust stream laden with VOCs, enters the heat exchange bed using a high-pressure fan system. Here, the stream passes directly through the media heating it in preparation for the combustion chamber. The combustion chamber then heats the stream further using burners to the optimal temperature for combustion to complete the oxidization process. After that, the clean stream is lead to the heat recovery chamber where it passes through the media bed, which cools the air and heats the media. The final step, which makes the 3-can regenerative thermal oxidizer more efficient, occurs in the final chamber, which traps any remaining VOCs in the “clean” stream, by purging the stream with clean air. The canisters operate under a “swing bed” absorption principle which is the principle of transfer through the beds using flow reversal. In the use of this principle with ceramic stoneware, the process is called regeneration. In the case of amine plants, the CO2 is collected and then further refined in other GCES deployed technologies to be used in enhanced oil recovery. Enhanced oil recovery is a method in which carbon dioxide is injected into the reservoir to remove oil that would not have been able to be recovered from the oilfield otherwise. EOR can increase oil extraction efficiency by as much as 40%.
Added Value in Captured Carbon Dioxide:
There are many uses for CO2 and many trading markets and tax incentives that encourage its use. The three most common sources of revenue for facilities capturing and liquifying carbon dioxide include:
- Solvent Recovery: Recovered carbon can be used in a number of manufacturing processes, including food and beverage, refrigerant, and fire protection.
- Carbon Trading: Carbon credits can be sold or traded between participating facilities. One ton of carbon equates to a single carbon credit, which is worth between $10 and $30 U.S. Dollars, depending on the market.
- Tax Incentives: Countries on nearly every continent are changing their regulations and attempting to incentivize industries to get on board with carbon emissions reduction.