A New Approach to Flowline Active Heating

Abstract

The industry drive to develop marginal fields, heavy oil, or increased oil-recovery options from new or existing fields requires that the design of system components be examined and questioned. Extended-reach (cold water) flowlines that transport unprocessed fluids from the wellbore through to a receiving or processing facility require effective insulation systems or an active heating system to assure the integrity of the fluids in the line. Additionally, to meet flow-assurance requirements, production chemistry is used at the inlet of a flowline to prevent the formation of hydrates and to manage paraffin wax or scale formation. The production chemicals are usually injected through chemical-transportation facilities in an electrical/hydraulic-control umbilical that is laid parallel to the flowline. Flowline active-heating systems and high-performance insulation systems add significantly to the capital cost of a project; additionally, the design and fabrication of control umbilicals that include multiple chemical-injection conduits increase the capital required to develop a field. This paper presents a new concept in flowline active-heating and chemical-injection systems that will reduce the capital cost of flowline and umbilical infrastructure while enabling significant flexibility in the application of production chemistry. The system challenges of existing flowline design, umbilical design, and the philosophies of field operational maintenance/pigging are reviewed.

Review of hydrate prevention methods for deepwater pipelines

“…The new concept configured so that the heating fluids exit the tube at a point in the pipeline and comingle with the produced products, and return to the host for processing/separation opposing traditionally heating outside circumference of the pipeline [24]. The concept comes in two modes; open circuit system and closed circuit system.…”