Value

Xodus has combined Flow Assurance with data analytics and workflow automation to deliver far deeper insights than traditionally possible. A North Sea client with little visibility of the risk for wax deposition in their wells gained valuable understanding of the sensitivity of wax deposition to uncertain parameters. The results mitigated the need for evaluation of expensive design alternatives for the completions and trees. 

Description  

Xodus is an industry leader in wax modelling. The range of sensitivities required to understand the risk of wax deposition is often large and the simulation durations can be on the order of weeks or months. Simulations employing multiple OLGA modules makes things more computationally intensive and therefore traditional engineering will focus only on edge of envelope scenarios to define the potential risks. Xodus uses workflow automation techniques and data analytics to run and analyse multiple OLGA cases in a fraction of the time compared to traditional approaches. This allows a much broader range of parameter sensitivities to be simulated and a better understanding of risk to be evaluated.  

Problem 

A North Sea client requested a study be performed to understand the risk of wax deposition in the production tubing of new wells. The wells were expected to be low temperature wells, and as such there was a concern of high deposition rates. This had a cost impact on the tree and completion design and procurement. Such concerns included tubing size and the requirement for insulation on the completion, which would have had a significant additional cost per well. The wells were gas lifted and modelling required OLGA’s FEMtherm module in addition to the OLGA Wax module to ensure the heat transfer effects of counter-current flow were captured to provide accurate thermal predictions.   

Solution 

• Define the range of parameter sensitivities for the wax analysis. This included a range of n-paraffin solubilities, wax diffusion coefficients, oil rate, GOR, WGR, gas lift rate, and wellhead pressure. 
• Utilise Xodus workflow automation tools to simulate over 700 combinations of input parameters and extract the key wax deposition outputs parameters. 

• Visualise the impact of the input parameters on the output parameters – in this case, the impact of oil rate, diffusion coefficient and wax solubility on the maximum wax thickness and total content in the tubing. 
• Produce an interactive visualisation that allows client interaction with the results to obtain an in-depth understanding of the parameter sensitivities.  

Benefit  

Benefits for the client  

• Unprecedented range of analysis; 

• Interactive results; 
• Better understanding of risk; 
• Cost saving on well completion and tree design.  

Benefits for Xodus  

• Demonstration of workflow automation; 

• Successful implementation of OLGA Wax and FEMtherm modules; 
• Challenging project with successful delivery of results.