Temperature monitoring and measurement of the Claus thermal reactor in sulphur recovery units is one of the most challenging applications in the oil and gas industry. Recently, market interest in unpurged thermocouples has increased with the introduction of new unpurged thermocouple designs utilising alternative thermowell materials such as monocrystalline sapphire.
New state-of-the-art equipment has been installed in the thermal stage of one of Europe’s largest Claus SRU units. Substoichiometric firing and a furnace designed with CFD calculations and a modern compact boiler system design based on detailed heat engineering and FEM calculations were key to the success of the retrofit. P. Foith of CS Combustion Solutions reports on the retrofit and how the novel combination of a CS low pressure swirl burner, additional mixing using a VectorWall™ and a new waste heat boiler design achieved the desired results.
Are the three “T”s (temperature, turbulence, time) of Claus unit ammonia destruction still meaningful with improved understanding of the thermal reactor? CFD models appear to be adequate at higher temperatures, e.g. 1,200°C, but not at lower temperatures, e.g. 800°C and 1,000°C. A. Keller, on behalf of the Amine Best Practices Group, reviews how meaningful the rules of thumb for Claus unit ammonia destruction really are.
With the sulphur content of crude oil and natural gas on the increase and with the ever-tightening sulphur content in fuels, refiners and gas processors will require additional sulphur recovery capacity. At the same time, environmental regulatory agencies of many countries continue to promulgate more stringent standards for sulphur emissions from oil, gas and chemical processing facilities. Rameshni & Associates Technology and Engineering discusses options for compliance with new regulations on emissions regarding IMO 2020 compliance and report on the results and evaluation of three case studies. Worley Comprimo reports on the revamp of a sulphur complex built in the late 1980s at a refinery in East Asia with the aim to increase the capacity, improve the availability and reliability and make the unit environmental compliant.
Sulphur’s annual survey of recent, current and future sulphur recovery unit construction projects maps the developing shape of brimstone production from fuel and gas processing plants worldwide.
EcoMax™ tail gas catalysts offer a sustainable and cost effective choice for tail gas catalysts. They are made from spent hydroprocessing catalysts, which reduces the environmental and socioeconomic impacts of sourcing fresh cobalt and molybdenum and therefore supports operators’ sustainability goals. B. Visioli of Porocel (a part of Evonik) discusses the benefits of catalyst reuse from hydroprocessing for tail gas treating.
Storm Uri which blanketed the southern states of the US with snow, and led to widespread power outages in Texas, has had a major impact upon US Gulf Coast and Southern-Midwest refined products supply. Most Gulf Coast refineries were shut down or forced to operate at reduced rates. IHS Markit estimated that more than 5.2 million bbl/d of Gulf Coast capacity and 730,000 bbl/d in PADD 2 was impacted by the winter weather at its height, and close to 20% of lower 48 US natural gas production was shut-in in the first half of February. A drop in crude oil production of between 2.2 and 4 million bbl/d was estimated.
Failure investigations, equipment design and process upgrade projects for SRUs often overlook the impact of water quality. In this article E. Nasat o of Nasato Consulting and L. Huchler of MarTech Systems explore impacts of higher heat transfer rates, control of boiler and condenser water chemistry, conventional equipment design/configurations and monitoring program designs. SRU operators can improve the effectiveness of their failure investigations by implementing a broader, more holistic approach that assesses equipment design, process conditions, operating protocols and water quality issues.
A. Bhargav and A. Krishnan of Helium Consulting Pvt. Ltd discuss how it is possible to reduce SOx emissions within the existing system setup of an oil refinery or gas plant through detailed analysis, expedited corrective actions and the use of automated algorithms in real-time, by using a digital IIoT solution to monitor, control and optimise.
New approaches and novel processing schemes employing oxygen enrichment in sulphur recovery units have been developed and commercialised. In this feature Siirtec Nigi, Linde, Blasch, Fluor and RATE report on their latest developments.