Nitrogen Injection Applications Emerge in the Rockies

Abstract

Nitrogen has recently emerged in the Rockies as an alternative to natural gas and carbon dioxiae. A number of fields, particularly in the overthrust, are using large volumes of nitrogen to increase the recovery of oil. The application of nitrogen in four Rocky Mountain nitrogen injection projects is described, giving r~servoir parameters, quantities of gas injected and some early predictions.In many gas injection projects an operator usually has a choice among alternative gases. After oetermining for each alternative the incremental barrels of oil recovered per thousand stanoard cuoic foot (MSCF) of gas injected and the rate of recovery, the operator should consider the following factors; the cost per MCF at delivery pressure at the field, the long term availability and reliability of supply, the physical and chemical properties, the incremental cost for corrosion and produced gas clean-up, and the impact of the Windfall Profits Tax.These factors are presented, discussed and compared for natural gas, nitrogen and carbon dioxide.

Cryogenic Fracturing of Wellbores Under True Triaxial-Confining Stresses: Experimental Investigation

“…Nitrogen is inert, and problems of clay swelling, clay migration, or oil and water emulsions are eliminated (Gottschling and Royce 1985). Cost is normally less than conventional hydraulic fracturing, and also cheaper than other gases (Clancy andGilchrist 1983, Gottschling andRoyce 1985).…”

Nitrogen Injection Experience to Development Gas and Gas Condensate Fields in Rocky Mountains

“…Prior to the 1970's when natural gas was inexpensive and plentiful and in-situ compatible with subsurface hydrocarbon fluid, natural gas obtained from produced or other sources was injected to maintain reservoir pressure or to affect high pressure miscible displacement in order to maximize hydrocarbon recovery and minimize retrograde liquid loss in volatile oil or gas condensate fields. Consideration of selection was discussed in literature (Clancy and Gilchrist 1983;Calvin and Vogel 1979). Nitrogen was chosen as a gas cap replacement gas for both technical and economic reasons as summarized below.…”

“…A number of fields ( Figure 1) such as Painter Reservoir Units (PRU), and Ryckman Creek in overthrust, Anschutz Ranch East (ARE), and Glasscock Hollow, used large amounts of nitrogen to increase hydrocarbon recovery as well as to maintain reservoir pressure. Some of the fields with reservoir characterizations had been presented in literature (Clancy and Gilchrist 1983). In these fields, gas condensate/volatile oil was initially produced driven by gas expansion, supplemented by solutiongas and some with aquifer.…”

Research on Mechanism of Enhancing Recovery of Heavy Oil With N2 Huff-n-Puff Assisted by Viscosity Reducer

“…N 2 huff-n-puff recovers oil by increasing power of heavy oil with inject N 2 . Compared to heavy oil thermal recovery, N 2 huff-n-puff is an effective heavy oil recovery method, which has low energy consumption and carbon emission (Clancy and Gilchrist, 1983;Hudgins et al, 1990;Zolghadr et al, 2013). Previous studies have found that N 2 reached low permeability channels during the first cycle of N 2 huffn-puff and formed foamy oil flow.…”

“…Foam has many excellent characteristics, such as blocking large channels firstly, water plugging, and oil defoaming. So foam was widely used in plugging water, profile control, and other aspects (Casteel and Djabbarah, 1985;Dalland and Hanssen, 1995;Hirasaki et al, 2005;Xu et al, 2012;Sun et al, 2016a;Li et al, 2019a;Li et al, 2019b). In order to solve the problems of poor mobility of heavy oil and serious gas channeling in N 2 huff-n-puff, a viscosity reduction agent was selected to assist N 2 huff-n-puff, which can not only reduce the viscosity of oil but also plug the larger channels.…”