WemcoTM Flotation Machine Designs

Lunch & LearnJuly 15, 2003

WEMCO Innovations

Introduction

• Cylindrical Depurator Design for Onshore and

Offshore Fixed Platforms and TLPs

• Dual Cell Depurator Design for Motion Application

Platforms

• Specific Recommendations for XXXXXX Platform

Cylindrical Depurator

• Design flow rates based on standard four minute

residence time

• Designs to meet Customer requirements – 2-5+ cells

• Various Seal Arrangements for Atmospheric to

Pressurized designs.

• No Fugitive Emissions

• Lower Power requirements than the conventional

Depurator

Cylindrical Depurator

1-Cell

Cylindrical Depurator

1-Cell

Cylindrical Depurator

1-Cell

Basic Performance ParametersTypical Removal Efficiency of 95%

Klempel Kinetic Equation:

E = ( 1 – [ ] x 100% )

k = Flotation Constant, Typically 1.2 for Depuratort = Flotation Cell Residence Time, 1.0 minutesn = Number of cells, 4 for Cylindrical Depurator

( 1 + k t )n

1

Cylindrical Depurator

Cylindrical Depurator

Cylindrical WEMCO Depurator Hydraulic Skimming

Skim Wing

Skim Door

Flow

Cylindrical Depurator

• No Internal Skimmer Assembly

• Skims by Fluid Motion

1-Cell

Cylindrical Depurator

Cylindrical Depurator PerformancePilot Test Data – 4-Cell Cylindrical DepuratorDate: Aug. 12, 2002

Location: Angola

Client: Confidential

Test # Test Date Sample time Rate,BPD

Chemical,Nalco 2069 A,

Retention time/per cell, sec.

Inlet oil, ppm

Outlet oil, ppm

Actual Efficiency, %

Projected Efficiency,%

1 30-Jul 8:06 12,200 66.39 103 11 89.3 96.62 10:40 12,379 65.48 109 2 98.1 96.53 14:50 12,720 63.78 69 6 91.3 96.34 31-Jul 15:14 12,930 62.6 74 14 91.9 96.15 15:56 10,900 74.3 92 2 97.8 97.36 1-Aug 6:20 12,710 63.72 57.2 5 91.2 96.27 10:10 12,670 63.93 85 3 96.4 96.38 10:40 11,860 68.23 76 2 97.4 96.89 2-Aug. 7:02 12,780 63.38 59 5 91.5 96.2

10 8:21 13,430 60.3 74 7 90.5 95.711 10:40 12,800 63.28 77 2 97.4 96.212 3-Aug. 6:27 12,610 64.23 146 11 92.5 94.513 11:00 12,770 63.4 44 3 93.2 96.214 4-Aug. 7:00 16,370 49.48 82 8 90.2 93.615 4:52 16,360 49.48 92 8 93.5 93.616 5-Aug. 6:38 16,450 49.24 37 4 89.2 93.517 10:46 16,850 48.07 99 2 97.9 93.218 6-Aug. 6:28 16,820 48.1 60 8 86.9 93.219 10:48 17,610 45.99 177 12 93.2 92.720 16:58 17,680 45.8 197 13 93.4 92.622 8-Aug. 6:18 17,810 45.48 49 5 89.8 92.423 9-Aug. 7:14 18,520 43.7 98 8 91.8 91.8

7-Aug. 6:48 17,760 45.67 27 9 66.7 92.5Note:

1 The pilot unit is rated for a flow of 13,500 BPD.2 The kinetic rate of 1.2 is used for evaluation.3 The number in red indicates the projected oil removal efficiency is greater than that of the actual number.

Cylindrical Depurator

1-Cell

Cylindrical Depurator

• Sizes from 5’ diameter to 10’ diameter

• Flows from 5,000 BWPD to 177,000 BWPD

• Prices typically less than Box Tank design

Dual-Cell Depurator

• Specifically designed for motion applications

• Two cells in series, central skimmings removal

• Shortened skimmings weir length

• Dual Controls for flotation compartment and

discharge box

• High pressure designs

Dual-Cell DepuratorBasic Performance ParametersTypical Removal Efficiency of 94-95%

Klempel Kinetic Equation:

E = ( 1 – [ ] x 100% )

k = Flotation Constant, Typically 1.2 for Depuratort = Flotation Cell Residence Time, 2.5-3 minutesn = Number of cells, 2 for Dual-Cell Depurator

( 1 + k t )n

1

Dual-Cell Depurator

Dual-Cell Depurator

WEMCO Dual-Cell Depurator Hydraulic Skimming

Skim Wing

Skim Door

Flow

Dual-Cell Depurator

Dual-Cell Depurator

1-Cell LT-3LT-5

LCV-3

LCV-5

Fro th Liquid Level

Liquid Level

Mechanism 1 Mechanism 2

LT-4

LCV-4

Dual-Cell Depurator

•Froth skimming occurs with centrally located trough that is the common baffle.•Secondary skimming occurs in discharge box through "ISF type" threaded pipe centrally located in cell.•Level control in the skim trough is controlled by LT-4 and LCV-4, either through the DCS or by pneumatic direct.•Level control in flotation region is controlled by LT-3 and LCV-3 through DCS.•Level control in discharge box is controlled by LT-5 and LCV-5 through DCS.•Design with two rotor mechanisms, draft tubes, and 2.0 - 3.0 minutes residence time per cell.•Water draft tube minimizes short-circuiting and rotor by-pass, improving efficiency and allowing maximum available capacity turn-down.

Dual-Cell Depurator

Dual-Cell Depurator

Dual-Cell Depurator

Platform XX Recommendations

•20,000 BWPD Design for Spar type Motion Application.

•Recommended Machine is Model 8-2C.

•Residence Time per Cell is 3.7 Minutes.

•Kinetic Removal Efficiency Calculated is 96.6%.

Model 8-2C Dual-Cell Depurator

Model 8-2C Dual-Cell Depurator

Model 8-2C Dual-Cell Depurator

Model 8-2C Dual-Cell Depurator

• Basic Machine – SA-516 Grade 70 Pressure Vessel on Saddles.• API RP 14C Compliant Nozzles for Instrumentation by Petreco or Others• Internally Lined with Carboline 1205 Glass Filled Epoxy.• Externally Coated with Carboline 3 part Offshore System.• Optional Upgrades:

- 316 SS Wetted Components- Skid, Drip Pan, Ladder, Platform(s), Handrails- Full Electrical