Developments in Antiscalant Delivery Technology

Abstract

This paper discusses the causes of scale formation and the evolution of antiscalant chemical injection systems in geothermal wells with examples of antiscalant projects. It covers the benefits of antiscalants such as reduced maintenance costs; stinger design; and the evolution of pumping systems in New Zealand and overseas. Calcium carbonate and other chemicals often deposit in well linings where two-phase geothermal fluid is present. The scale rapidly forms a rock-like substance on the side of the well casing and reduces the well’s production capacity over time. The traditional solution to counteract this build-up was to “work over” the well with a drilling rig that reamed out the deposits in an attempt to improve the well’s production rate. MB Century has developed antiscalant injection systems for the last 25 years. The antiscalant systems have been proved to be practical and cost effective solutions to reduce the cost of major well maintenance and maintain production. This paper also reviews the various stinger designs used in geothermal antiscalant applications.