TRANSFORMING WATER TREATMENT
FOR A SUSTAINABLE FUTURE
RIMA PLANT
Petroleum Development Oman (PDO) is a leading oil exploration company in Oman delivering the majority of the country’s crude oil production and natural gas supply. PDO’s mission is to safely and sustainably manage oil and gas wastewater at low costs. In June 2020, PDO contracted with RWTP with a project using advanced wetland technology under a Design-Build-Own-Operate-Maintain (DBOOM) agreement. The project was initiated in June 2020 and operations began in July 2022. RWTP now operates a 40,000 m3/d wetland facility for 20 years, efficiently removing oil and biological contaminants.LOCATION
PROJECT LOCATION & SITE
The project site is located at 700 kms from Muscat and about 200 km from the nearest commercial airport at Duqm. The total plot area is 25.5 km².
25km²
Plot
1.3km²
for 3 tracks of wetlands for biological oil removal process
3km²
for evaporation
TECHNOLOGY
Cutting Edge Technology
Sustainable Technology LLC – SusTeco ME, the designer and consultant for this project, provided the technology. This comprehensive project includes diverse infrastructure, facilities, and environmental components designed to meet various operational needs and environmental considerations
Electricity and Pipeline Infrastructure:
- Configured in a Z-configuration with a flow computer.
- Housed in a 20’ container, equipped with an Uninterruptible Power Supply (UPS).
OPW Fiscal Metering Station:
- Configured in a Z-configuration with a flow computer.
- Housed in a 20’ container, equipped with an Uninterruptible Power Supply (UPS).
Main Electrical
Room:
- Housed in a 40’ container.
- Equipped with a transformer and two generators.
Camp
Facilities
- Offices, workshop, and accommodation for up to 40 employees.
- Laboratory, prayer room, gym, clinic, TV room, and mess hall.
Groundwater Monitoring:
- Installation of monitoring wells around the site by PDO.
Pipeline and Stilling Basin:
- A pipeline extending 1,300 meters from the metering skid to the Stilling Basin (SB).
- The SB is a High-Density Polyethylene (HDPE)-lined earth pond with a diameter of 144 meters and a height of 11 meters.
Oil Removal
Facilities:
- Incorporation of oil removal facilities and a temporary oil storage tank.
Overflow Wetland (OW):
- Comprises three tracks with four terraces.
- Covers a vast area of 1,300,000 square meters with a mineral sealing layer (MSL).
Area for
Evaporation (AE):
- Features an embankment dam.
- Spans a maximum area of 3,000,000 square meters.
PROCESS
PROCESS FLOW
Timely Construction
The construction phase, undertaken during the challenging COVID period, was completed in just two years, meeting the set timeline.
Massive Earthwork
Over 2.2 million cubic meters of soil were moved to establish the current plant,demonstrating a remarkable feat in engineering and logistics Maximum Capacity
The plant currently operates at its maximum capacity, achieving the expected performance standards right from the start.
Expansive Plot
The 25-square-kilometer plot is strategically designed to house the processing facility, site office, and worker accommodations, with ample space for future expansion.
Long-Term Commitment
The Operation and Maintenance period spans 20 years, up to 2042, ensuring sustained efficiency and environmental responsibility.
Performance-Driven Contract:
The contract is underpinned by performance-based KPIs, especially related to capacity-related criteria.
Innovative Treatment
The process relies on specific bacterias and micro-organisms to efficiently degrade the residual oil, reflecting an environmental friendly approach to water treatment. Cost-Efficient Design
The plant’s design prioritizes equipment and lagoon accessibility, resulting in reduced operational and maintenance costs.
- Dual flow-meter in Z-configuration for redundant and automatic/instantaneous control.
- Used for invoicing between PDO and RIMA with a proven accuracy of 0.2 % according to ISO/ICE 17025.
- Designed for potential extension to 60.000m3/d.
- Sampling point for raw water analysis.
- Fenced zone including control room, genset and MCC.
The SB has 2 main tasks, to dissipate the energy and reduce the flow velocity of the incoming OPW by a helical movement in a concentric path and by providing enough retention time (almost 2 days retention time) for the oil to float. As the water will flow along the concentric path with a reduced velocity, the oil will start separating. The retention duration will support the oil to rise and this will be extracted with help of the oil skimmers.
Main Features:
- Construction reinforced earth-dam.
- Inside surface sealing with 2mm HDPE Liner.
- Inlet arrangement is with PE pipe directly welded to the HDPE lining.
- Outlet structure RCC with Epoxy coating with GRE outlet pipe sealing .
- For protection Purpose the inner ramp is covered with interlock.
- Floating barrier and tangential incoming flow, allowing easier oil collection.
- Floating platform for operation of skimmers.
- Oil extraction in Stilling Basin by 4 pneumatic drum skimmers, with pneumatic oil pumps.
A storage facility is built for storing the skimmed oil from the SB. The storage tank has a storage capacity of 10 days approx 170m3.
Main Features:
- Bottom slab in RCC.
- Wall in concrete blocks with reinforcement and concrete filling.
- Sealing with 1.5 mm HDPE lining, outside fixed with galvanised CS ring.
- transfer by tanker back to PDO facility.
- Pumping station to send back to SB the potential residual water.
The SA is an important process step with the task to remove as much as possible from the dissolved H2S content of the OPW reaching the OW area.
Main Features:
- Designed as a water ramp with huge turbulence in order to strip-out the H2S.
- Sealed with HDPE and a PCC bed on top holding the vertical concrete blocks, creating the turbulence.
- Distribution between the 3 process streams with valve chamber.
The OW (Overflown Wetland) is divided into 3 tracks with 4 terraces each. After passing the SA the OPW reaches this region. The task of the OW is to remove the organic pollution like the hydro-carbons. The OPW is purified by the biological actions which consist of biodegradation by micro-organisms and bacterias.
Main Features:
Main Features:
- Designed as shallow ponds with a MSL (Mineral Sealing Layer).
- Embankments are sealed with HDPE lining.
- At the end of each terrace are effluent pipes installed, each fitted with a skimming ring.
- On its long way and slow movement through the water body of the terraces the treatment process takes place.
The task of the AE is simply the evaporation of the remaining water.
Main Features:
- Designed as earth pond localised by an earth dam (AE dam) on 3 sides and by the central hill on the other side.
- Total surface of ca 300 ha (3,163,810 m2).
- The AE is sealed with an environmentally friendly in-situ MSL (Mineral Sealing Layer).
- The AE dam is designed as an earth dam with technical sealing.
- 2 emergency overflow area paved with interlocks directly placed on the geotextile and fixed with PCC shoulder.
Task of sampling and analysis is to provide detailed insight of the plant treatment performance for optimising the degradation process by internal site laboratory complying with the international standards with a cross verification on a regular basis with a 3rd party laboratory.
OPERATION & MAINTENANCE
O&M BY VEOLIA
The Operation phase of this This 20-year Design-Build-Own-Operate-Maintain (DBOOM) contract commenced on 22 July 2022. The design emphasizes efficient equipment and lagoon accessibility to reduce O&M costs. VEOLIA, one of the shareholders, manages a range of critical O&M tasks, including handling oily water, proper oil removal, close monitoring of all water characteristics, and site preservation. The remote location requires a small, skilled team for multitasking. VEOLIA also commits to an “In-Country Value” initiative, engaging Omani universities in research projects, and ensures compliance with PDO contract commitments, VEOLIA standards, and value addition to PDO, the end customer.
HSE
Our Safety Performance during Construction Phase
NO
Fatality recorded
during execution
1.3 MILLION
LTI-free Manhours
1 MILLION
Kilometers driven without
a road traffic accident
TRAINING
Delivering intense HSE session Target
Zero LTI Standards applying Veolia & International HSE Standards
HSE AWARD
Our steadfast commitment to Health and Safety has been honored with a distinguished award. This recognition underscores our resolute dedication to maintaining safety as our utmost priority and serves as a testament to our ongoing efforts to elevate standards in ensuring the well-being of our workforce and the environment.
No Loss-Time Injury has been recorded since the start of the O&M Phase of the Contact and RWTP strives to maintain the highest standards of HSE