Browse Prior Art Database

Predicting and Mitigating Hydrates in Deepwater Product

IP.com Disclosure Number: IPCOM000182701D
Publication Date: 2009-May-05
Document File: 47 page(s) / 2M

Publishing Venue

The IP.com Prior Art Database

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 9% of the total text.

Page 1 of 47

PREDICTING AND MITIGATING HYDRATES IN DEEPWATER PRODUCTION

Authors

Robert L. McKee
Chief Technology Engineer The M. W. Kellogg Company 601 Jefferson Avenue,
P. O. Box 4557
Houston, Texas 77210-4557

Hamid Neshan
Senior Processing Engineer The M.W. Kellogg Company 601 Jefferson Avenue
P. O. Box 4557
Houston, Texas 77210-4557

    To be presented at the International Hydrate Conference 20-24 June 1993
New Platz, New York

[This page contains 1 picture or other non-text object]

Page 2 of 47

PREDICTING AND MITIGATING HYDRATES IN DEEPWATER PRODUCTION

ABSTRACT

Hydrate formation is a potentially serious problem in any deep water production facility where the produced oil/gas/water could drop into the hydrate forming region. Hydrate formation can occur anywhere from the wellbore to the sales pipeline in multiphase production systems.

Prediction of hydrate formation depends on the accurate evaluation of the transient pressure temperature profiles of the system under different modes of operations.

A simplified model was used to evaluate the overall heat transfer coefficient of the wellbore to account for the complex and transient heat losses to the formation. By coupling the model with a reliable steady-state two-phase flow pressure drop correlation it was possible to predict the temperature profiles anywhere in the system formation. Using this technique it was possible to assess the effectiveness and practicality of different hydrate prevention or mitigation measures.

It is believed that the proposed procedure is a very useful and reliable tool to analyze any subsea multiphase production system regarding the problem of hydrate formation.

[This page contains 1 picture or other non-text object]

Page 3 of 47

PREDICTING AND MITIGATING HYDRATES IN DEEPWATER PRODUCTION

INTRODUCTION

The purpose of this study was to develop a basis for dealing with the threat of hydrate formation at all stages of production from well bore to sales pipeline for both a Tension Leg Platform (TLP) and a split Floating Production System (FPS). Each system consisted of 35 template wells and 5 satellite wells. The distance of the satellite wells from the production riser was about three miles. Figures 1-3 show the typical configuration of different production systems. For TLP wells the chokes could be installed at the surface, the Christmas tree, or at the template. For FPS the chokes could be installed at the Christmas tree or at the template.

Four types of producing wells were considered for each production system:

1. Gas wells producing 20 MMSCFD of gas.

2. Oil wells producing 2000 BBLS/D of oil.

3. Oil + Gas wells producing 20 MMSCFD gas and 2000 BBLS/D oil.

4. Oil + Gas + Water wells producing 20 MMSCFD gas plus 2000 BBLS/D oil and 200 BBLS/D water.

The production flow for all cases started at 7500 psia and 21 JOF at a depth of 13000 feet. Each case ended at...