Multiple Stage Hydraulic Jet Pump Presented to ALRDC Presented by: Alex Hageman (Accelerated Production Services, Inc.) May 15th, 2013 Background Information Single hydraulic jet pumps are well known and documented for oil & gas production. Power fluid is pumped down to the nozzle and at the nozzle exit converts high pressure low velocity fluid to low pressure high velocity fluid. In the mixing chamber the production fluid is drawn to the low pressure area and mixes with the power fluid. Mixed fluid enters the diffuser where the low pressure high velocity fluid expands and converts the fluid to high pressure low velocity to lift to surface. 2 Single Stage Limitations The production fluid pressure (Pump Intake Pressure) of the fluid must be high enough compared to the power fluid, or the jet pump will cavitate. Cavitation occurs when the local static pressure in a fluid reaches a level below the vapor pressure of the liquid at the actual temperature. The vaporization itself does not cause the damage - the damage happens when the vapor almost immediately collapses after evaporation when the velocity is decreased and pressure increased. This limits the amount the well can be drawn down by jet pumps without damaging the pump components. Hydraulic jet pumps cannot produce low bottom hole pressure wells due to possible damage to jet pump components (due to cavitation) thus requiring repair and down time. 3 Goals and Objectives Want to maintain the ability to retrieve the pump hydraulically without wire line or work over rig. Prefer to use hydraulic jet pumps over piston pumps because they are inherently lower cost initially and repairs can be done in the field. Develop a system that would reduce the required PIP to expand the application window for the hydraulic jet pump and minimize cavitation damage. Operate at very low pressures for gas well de-liquification. – Operate at lower pressures to draw down wells and increase productivity. – 4 Known means to address cavitation Small throat and nozzle (T&N) combinations can operate with low intake pressures with damage but cannot pump from deep wellbores. Large T&N combinations can pump from deep well bores but require relatively high pump intake pressures to operate properly. 5 Multiple Stage Jet Pump Concept The multi stage jet pump uses a smaller T&N combination in the first stage to “boost” or “charge” the second larger T&N stage in order to produce the fluid out of the wellbore. This could allow a jet pump to be used in lower BHP wells for oil production or gas well de-liquification. We also have the option to use an orifice plate in the jet pump to reduce the power fluid pressure at the first stage. This would also theoretically help to reduce cavitation in the first stage of the pump. 6 Testing Focal Points Efficiency (Ep) Hydraulic Horse Power (HHP) Injection Pressure (Pn) Pumping Intake Pressure (Ps) Suction Flow Rate (Qs) 7 Test Results (5.10-5.11) In some instances the two stage was able to outperform the single stage in draw down and efficiency. Inflow rate, injection pressure and discharge pressure remained constant. – Inflow 90 BPD, Injection Pressure 290 psi, Discharge Pressure 100 psi • Single Stage – 72 psi PIP, 6.5% EFF and 1 HHP • Two Stage – 4.8 psi PIP, 10% EFF and 2 HHP – Inflow 120 BPD, Injection Pressure ~290 psi, Discharge Pressure 100 psi • Single Stage – 72 psi PIP, 8% EFF, 1 HHP • Two Stage – 16 psi PIP, 13% EFF, 1 HHP 5.10 – Single Stage 5.11 – Two Stage 8 Test Results (5.12-5.13) Some instances, at the higher Inflow rates the single outperformed but at the lower inflow rates the two stage started to improve the draw down and efficiency. Inflow rate, injection pressure and discharge pressure remained constant. – Inflow 160 BPD, Injection Pressure ~560 psi, Discharge Pressure 100 psi • Single Stage – 60 psi PIP, 3.3% EFF and 4 HHP • Two Stage – 75 psi PIP, 1.4% EFF and 7 HHP – Inflow 100 BPD, Injection Pressure ~550 psi, Discharge Pressure 100 psi • Single Stage – 55 psi PIP, 2.5% EFF, 4 HHP • Two Stage – 32 psi PIP, 2.5% EFF, 6.4 HHP – Inflow 40 BPD, Injection Pressure ~540 psi, Discharge Pressure 100 psi • Single Stage – 48 psi PIP, 1.1% EFF, 4 HHP • Two Stage – 1 psi PIP, 1.4% EFF, 6 HHP 5.12 – Single Stage Test 5.13 – Two Stage Test 9 Test Results (5.16-5.17) Leaving the inflow rate and pressure constant the two stage pump was able to use less HP and was more efficient to operate the set conditions. – Inflow 200 BPD, PIP ~30 psi, Discharge Pressure 100 psi • Single Stage – 9 HHP, 3% EFF, Inj Press 850 psi • Two Stage – 7 HHP, 4.6% EFF, Inj Press 500 psi – Inflow 150 BPD, PIP ~15 psi, Discharge Pressure 100 psi • Single Stage – 9.5 HHP, 2.6% EFF, Inj Press 875 psi • Two Stage – 7 HHP, 4% EFF, Inj Press 500 psi – Inflow 100 BPD, PIP ~5 psi, Discharge Pressure 100 psi • Single Stage – 12 HHP, 1.4% EFF, Inj Press 1000 psi • Two Stage – 7 HHP, 3% EFF, Inj Press 500 psi 5.16 – Two Stage Test 5.17 – Single Stage Test 10 Testing Comments Test were done in a controlled setting with lower pressures relative to normal down hole jet pump. This is why the efficiencies were lower than normal jet pump efficiency. We don’t want people leaving here believing jet pumps are 1% efficient. That’s not representative. But we do believe the comparisons of improvement are relative to given wellbore conditions. Jet pumps operate with better stability at higher pressures. Testing results were very diverse with some two stage pumps showing no improvement over the single stage. 11 Conclusion The tests prove the two stage jet pump can lower the pump intake pressure further than the single stage jet pump because it uses a smaller stage to create the lower pressure area. Multiple tests showed the two stage jet pump was more efficient and consumed less horse power while creating a lower pump intake pressure. In the some of the tests, the two stage jet pump did consume more horsepower and was slightly less efficient than the single stage jet pump but had a lower pump intake pressure. (We assume for gas well de-liquification, trading horsepower or efficiency for operational performance is acceptable because the power required is low anyway.) In summary the two stage jet pump can outperform the single stage in drawdown, efficiency, and horsepower if sized correctly. More tests need to be done at more normal or typical down hole operating conditions to fully understand how the two stage pump will perform. 12 Next Steps We believe the next logical step would be to conduct tests under actual well conditions Gas well de-liquification would be appropriate to understand low PIP capabilities without issues with other potential problems such as frac sand, paraffin, etc. – Oil wells where deviation is an issue for rod pumps but wells where paraffin is not an issue would also be worth investigating. – Determine if the orifice plate is needed to reduce the first stage power fluid pressure. – We would like to be able to gather empirical data with the tests to test the sizing program. – 13 Thank you for you time. Questions?