New Process Scheme for Treatment and Reuse of Desalter Effluent

Diego Carrasco Torrecilla, Veolia Water Technologies Oil & Gas

Mouloud Hendou, Veolia Water Technologies Oil & Gas

Vilas S. Koleshwar, Saudi ARAMCO

➢ Traditional treatments for Desalter Effluent are generally difficult and

expensive:

➢ Traditional filtration methods do not work without exhaustive and expensive pre-

treatment.

➢ Poor effluent quality and clogging with media filtration

➢ Short membrane life, low flux, frequent cleaning and membrane failures of polymeric membranes

➢ High temperature, presence of toxic organics and frequent salinity variations

jeopardize biological treatments

➢ Requires cooling to protect membranes and/or biomass, then reheating

➢ RO Membrane particulate and organic fouling is a common problem

➢ Often, Desalter Effluent is reinjected or diluted with larger streams – when

available –, to minimize the negative effect on wastewater treatment plants.

➢ No current proven or reliable technology available for Reuse

➢ In response to the technical challenges faced by the industry, and underits innovation program, Veolia Water Technologies Oil and Gas (VWT O&G)has developed a novel process scheme for Desalter Effluent reuse.

➢ The process is based on removal of Oil, TSS, BTEX, PAH and otherdissolved organics from water, followed by high-temperature desalinationto decrease the TDS to the desired level.

➢ It allows 62-75% reduction in both wash water demands and wastewatergeneration, depending on Desalter Effluent quality.

➢ In collaboration with ARAMCO, this process has been pilot tested in 2016at Train 4, Khurais Central Processing Facility, KSA.

➢ The process operates at process temperature (typically from 55 to 75°C)

while meeting recycled wash water quality and process integrityrequirements.

DESALTER

Wash Water

Desalter Effluent

Desalted Oil

100% 100%

Oil + Water

Re-injection

Dilution & treatment in WWTP

➢ Typical Desalter Schematic without VWT O&G Reuse Plant:

DESALTER

Wash Water

High TDS Reject

Desalted OilOil + Water

100%VWT O&G Reuse Plant

62-75%

25-38%

20-28%

TSS & Oil Concentrate

5-10%(Optional partial recycle to phase

separators)

Evaporation

Re-injection

To WWTP

Oil Recovery / slops

Sludge Treatment

Recycle to Inlet

➢ Desalter Schematic with VWT O&G Reuse Plant:

➢ Pilot Plant details:

➢ 3.8 m3/h, 63-74% overall recovery

➢ 24 hours/day, 7 days/week operation

➢ Operating Temperature 55-65°C

➢ TiO2 & SiC, MF & UF tried

➢ Oil & Solids removal

StrippingMPRA

(Macro-Porous Resin Adsorption)

HTRO(High temperature Reverse Osmosis)

➢ TOC reduction

➢ RO protection

➢ H2S & BTEX removal

➢ 2 stage unit

CUF(Ceramic Ultra-Filtration)

➢ Dissolved Salts removal @ high temperature

90-95% rec. >99.9 % rec. >99.5 % rec. 70-80% rec.

CUF

CUF

➢ Different Veolia’s ceramic membranes tested:

➢ Different operational parameters tested depending on different Desalter Effluent Oil & TSS levels observed.➢ Filtration flux > 150 L/h/m2 (150 – 230 L/h/m2 range)

at 90 – 92,5% recovery

➢ Automatic CEB every 12 – 36 h (depending on operating flux)

➢ CIP every 7 – 20 days (depending on operating flux)

Membrane Type TiO2 UF SiC MF SiC UFFiltrate TSS range, ppm 1.6 - 11.2 2.1 – 6 1.7 - 4Filtrate Oil range, ppm 0.7 - 12 1 1 - 4Filtrate SDI range 0.8 - 3.0 N/A 0.3 - 0.6Filtrate Flux, LMH 48 - 143 200 152 - 228

MPRA

➢ Cycle 2: MPRA Saturation test-kit results

➢(1): (time between regenerations >> 1 month)

Bed Volumes COD Removal rate

2100 83%5500(1) 54%

HTRO➢ Gradual Recovery

increase tested, from 60-

70% to 75-80%

➢ Initially with fixed Pressure

control, then changed to

fixed flow control, due to

frequent TDS variations in

Feedwater.

Conclusions

➢Desalter effluent can be reused without need of cooling or dilution with other streams.

➢Target quality was reached and maintained well below target during the whole

duration of the pilot.

➢Overall hydraulic recovery target was met and gradually increased, and further

recovery increase opportunities have been identified for full-scale plants.

➢CUF and MPRA have proven to be a compact, robust and suitable pretreatment for

Desalter Effluent Reuse.

➢The process was stable and robust, able to treat Desalter Effluent which presented

continuous quality variations.

VWT O&G Associated Patents

➢ METHOD FOR TREATING INDUSTRIAL WATER BY PHYSICAL SEPARATION, RESIN

ADSORPTION AND REVERSE OSMOSIS, AND CORRESPONDING INSTALLATION

➢METHOD AND FACILITY FOR THE TREATMENT OF WATER FROM OIL AND GAS

INDUSTRIES, ESPECIALLY WATER PRODUCED FROM OIL AND/OR GAS FIELDS

➢METHOD AND FACILITY FOR TREATING HOT INDUSTRIAL WATER

VWT O&G Contact point

Ghassan Legrand Ph. +33 (0)1 40 83 65 53 ghassan.legrand@veolia.com