Sand Cleaning & Disposal Systems

Sand Cleaning 3D

Overview

The Cyclotech Sand Receiving, Cleaning and Disposal Systems have been designed to provide an efficient, compact and robust solution to the post separation treatment function. The scope of this post separation function will largely depend on the method of solids disposal which in most cases is one of the following:

To Sea (overboard disposal);
To Reservoir (solids re-injection);
To Landfill (bag and transport, ship to shore, pipe to settling pit).

The main functions of a Cyclotech Sand Receiving, Cleaning and Disposal System are as follows:

RECEIVE: Receive raw oily sand from a production separator or other solids accumulator via a jetting sequence. All disposal options will require this function;
CLEAN: Remove hydrocarbons from the sand and the associated water. The requirements for this function will be most severe if the solids are to be disposed to sea;
DISCHARGE: Discharge clean sand in clean water. This function is straightforward for sea and reservoir disposal options but requires a bagging solution or alternate for landfill disposal.

Typical sand discharge specifications delivered by the Cyclotech Sand Cleaning systems are as follows:

Oil on Sand – <0.5% wt;
Oil on Water - <30 mg/l.

System Design

The main elements of the system are:

Cyclotech MC Series Desanding Hydrocyclones
The MC-25 (1”NB), the MC-50 (2”NB) and the MC-100 (4”NB) providing particle separation down to sizes ranging from 5 to 40 microns. Materials of construction are Composite Ceramics, Engineering Grade Alumina Ceramic or Reaction Bonded Silicon Carbide for ultimate wear resistance;
Integrated Conical Bottomed Solids Accumulator
To collect and process the sand. The accumulator can be sized to provide any solids hold up requirement and typically has a conical bottom to maximize solids removal efficiency;
Cyclotech SANDSCAPE ^® Solids Fluidisation and Conveyance
This Cyclotech SANDSCAPE^® is a proprietary technology designed to draw solids in a controlled concentration from the bottom of the accumulator and boost the pressure to allow the slurry to be routed back to the Desanding Hydrocyclone inlet. It is located external to the integrated Accumulator. Materials of construction are typically a carbon steel or a stainless steel outer housing with replaceable high wear resistance Reaction Bonded Silicon Carbide cartridge style internals.

Receiving Function

The first step is to transfer separated solids from any part of the process (e.g. separator jetting, Produced Water Desanding Hydrocyclone accumulators, Wellhead Desanding accumulators) to the sand receiving system accumulator. The solids are conveyed as a slurry and thus this is a conventional solid liquid separation.

Cleaning Function

The solids in the accumulator are then recirculated back through the Desanding Hydrocyclones using the Cyclotech SANDSCAPE^®.

To meet the oil on sand specification, the oil on sand is removed by:

Attrition forces between the sand and the inner cyclone wall generated by the high intensity shear fields of the MC Series Desanding Hydrocyclones;
Attrition between the sand and the SANDSCAPE^® internals generated by the high pressure, high velocity clean water motive fluid.

To meet the oil in water specification, the oil in the water is removed by:

Displacement of oily water with clean flush water as the re-circulation progresses. The oily water is removed from the system via the Desanding hydrocyclone overflow;
As the cleaning cycle progresses, the solids are re-circulated in increasingly cleaner water.

Samples can be taken during the re-circulation cleaning cycle to ensure the solids and associated water meet the required specs prior to disposal. Sand Samples Dirty Clean

Disposal Function

If the sand is to be disposed to sea or re-injected back into the reservoir, the SANDSCAPE^® will transfer the solids at a controlled concentration to either an overboard disposal caisson or a solids re-injection system.

If the sand is to be disposed to landfill, Cyclotech can offer the following disposal options:

Removable solids accumulator;
Transfer to skip – dewatered and discharge solids into a standard mud box or cuttings skip;
Solids bagging system – dewatered and discharge solids to a housing containing a 1m³(typical) permeable bag. These bags, once solids filled and drained of liquid, can be either transferred to, or emptied into, a skip or mud box.

Design Features

Cyclotech’s Sand Receiving, Cleaning & Disposal systems incorporate the following features which are of paramount importance to successful implementation:

The Desanding Hydrocyclones must be able to cope with the high solids concentrations in the feed from the jetted separator;
The system must be able to control the solids concentration in all slurry pipework;
The Desanding Hydrocyclones must be able to provide the required cut size to ensure no sand is returned to the process;
Suitable sand accumulator capacity is provided (if batch operation is used);
Optional – Deoiling system to process discharged oily water

Benefits

The benefits of Cyclotech's Sand Receiving, Cleaning & Disposal systems include:

No requirement for a slurry pump;
The SANDSCAPE^® controls and limits the sand concentration, irrespective of the amount of sand in the accumulator. This prevents blockage problems during the clean and discharge functions and maximizes plant availability;
Reduces oil in water as well as oil on sand to meet all discharge specifications;
No moving parts;
Simple, reliable, flexible and can be easily automated.

New-Build Systems

Cyclotech’s Sand Receiving, Cleaning & Disposal systems form an integral part of our Sand Management capability. They can be integrated with our proprietary SCARPA^® separator sand jetting systems to provide a robust and environmentally compliant sand management system. These systems can range from fully automated packaged systems to stand alone vessels. Standard pressure vessel designs are available at most design pressures and temperatures and to most common design codes such as PD5500, ASME VIII, AS 1210 or GOST-R. Materials of construction range from standard and low temperature carbon steels through to most stainless steels such as Duplex, 6Mo, Super Duplex, 625, 825 and other alloy steels.

Field Testing.

Cyclotech has a range of MC Series single liner test units (up to 300#), which can be used to determine the separation and cleaning performance of the differing MC Series models on live fluids. These test units are compact, require no utilities and come complete with all required valving, instrumentation and hosing. Cyclotech can also perform a full particle characterisation analysis of the existing Produced Water Treatment system as part of these performance trials. This includes particle size distributions, average solids concentrations and oil on solids analysis.

Leased Equipment

Cyclotech own a fleet of flexible, production scale (up to 20,000 bpd) skid mounted Sand Management packages available on long or short term lease contracts. The equipment is available globally but supported at a local level which allows Cyclotech to assist the customer in the design, integration, operation and manning of these temporary systems.

Please contact us if :

You are proposing to install a Sand Cleaning system;
You have problems with your sand-jetting system;
You have started to produced sand but have no topsides sand handling capability.

Available Resources

Sand Receiving & Cleaning Systems (English)

PDF - 1.37Mb

Brochures

Sand Receiving & Cleaning Systems (Chinese)

PDF - 1.6Mb

Brochures

MC Series Desanding Hydrocyclone

XLS - 180Kb

Product Enquiry Questionnaires