TerraChem offers the top and most comprehensive hydrocarbon decontamination package in the market today: A state of the art decontamination or chemical cleaning formulation, unmatched technical background and expertise, and very competitive pricing. Guaranteed!

TC-5000 is a proven new generation formulation that is highly effective for removing light and heavy-end hydrocarbons from the process units.

TerraChem offers highly experienced technical support for the pre-engineering and execution of the
decontamination / chemical cleaning projects in the oil-refining and petrochemical industries, and specialises in designing and executing Full-Unit Decontamination job scopes, where the entire unit can be decontaminated within a 30-hour period, on average. TerraChem will assist the client in designing the most efficient and cost-effective circulation loops to decontaminate either complete or partial refinery units, such as Crude and Vacuum, Coker, Thermal and Hydro-Crackers, FCCU, and others.

TerraChem also provides its clients with comprehensive written procedures and loop diagrams to ensure the job execution is carried out safely, timely, and effectively. All the decontamination procedures and circulation loops are designed with thorough input from the unit's operations and process engineering personnel. Hence, by the time of the project execution, TerraChem's decontamination experts ensure to have achieved seamless integration with the client's turnaround management and operations team.

TC-5000 is a new-generation hydrocarbon decontamination formulation that is environmentally safe, fully biodegradable, and compatible to all metallurgy. It is a blend of surface-active chemicals in a benign, highly effective solvent. The anionic and nonionic surfactants and the solvent in TC-5000 are exceptionally effective in removing heavy-end hydrocarbons such as vacuum residue and asphalt, as well as light end hydrocarbons such as benzene, from the process vessels in refineries and petrochemical plants.

Typical concentration of TC-5000 for a process application is 1% in water. This aqueous solution of TC-5000 is circulated in a closed loop through the plant process vessels and piping at 80º to 90ºC for 8 to 12 hours (wash cycle). In the wash cycle, TC-5000 forms a stable emulsion with the hydrocarbons present in the plant equipment and piping. At the end of the wash cycle, the emulsion is pumped out of the system, thus transporting the trapped hydrocarbons out of the system. The system is then rinsed with fresh water to displace the residual emulsion out of the system. At the end of the rinse cycle, and once adequate ventilation is provided, the decontaminated unit will have zero LEL, less than one ppm of benzene, and zero H2S.


Vacuum Bottoms Sample after
Water-Push and Steaming

Vacuum Bottoms Sample with
TC-5000 Oil-in-Water Emulsion

Vacuum Bottoms Sample
after TC-5000 Wash
Before the wash procedure is initiated, refinery personnel will complete the normal plant shutdown procedure. All equipment to be decontaminated will be pumped out and depressurized. Heavy circuits will be flushed with light oil at maximum velocities in order to bring down the pour point of the remaining heavy hydrocarbon below 90 degrees C. Following this step, all circuits will be pushed with water or steam to displace free hydrocarbons as best as possible.

Once most of the free oil is displaced and then drained (free oil must not exceed 20% of loop volume) the system is charged with water to normal operating levels and placed under self-sustained circulation. Steam injection is used to raise the temperature of the solution to 80 to 90 deg C.

The system is normally circulated for a period ranging between 8 to 12 hours. During the decontamination process, the equipment will be vented first to the flare system and afterwards to the atmosphere.

The temporary pumps used to circulate the water/chemical solution, if any, will be connected to the process equipment by means of temporary piping spools and high-pressure-and-temperature rated hoses.

The effluent generated during the decontamination process is typically pumped off to a holding tank, where the aqueous phase is then discharged to the plant waste water system and the oil is sent to the slop tank for re-processing.​​​​​​​
TC-5000 is a highly effective vapour phase decontamination product, as it has a high solvency value and in vapor phase it can access surfaces and deposits that cannot be contacted by liquid flow. Vapor Phase application is particularly effective on light end products and offers rapid decontamination with minimal effluent generation making it an increasingly popular methodology with our clients.

TC-5000 chemistry is educted into a steam source. The steam carries the TC-5000 chemistry throughout the process vessels. The solvent in the product partially vaporises, dissolving the hydrocarbons as it traverses the vessel. The surfactants in TC-5000 form an emulsion with the hydrocarbons and the condensed steam. This emulsion is then drained from the process vessels and the vessels are steamed again to remove the residual product, completing the decontamination cycle.

The specific mode of application, such as vapor phase or liquid circulation, or a combination of the two, is tailored during the site visit, where the exact scope of work and availability of resources is discussed in detail with the plant personnel.
Utilising years of exceptional refinery process experience, TerraChem are the leading specialists in full unit decontamination. Using a combination of liquid and vapour phase techniques, TerraChem are able to decontaminate the entire refinery unit from the battery limit to flare including all piping, exchangers, heaters, columns and vessels in parrallel ready to handover for maintenance and hot work.

Decontaminating the entire unit, as opposed to individual equipments or circuits, offers obvious safety advantages during maintenace alongside timesavings through minimising blinding and hydrojetting requirements. Furthermore, having cleaned all unit piping the fouling traditionally left in piping will not be drawn into the heat exchangers during startup where it would then provide a seed for fouling to develop on the exchangers. This offers improved operational efficiency on startup and prolonged running time until the next shutdown.

Full Unit Decontamination is a complex process in which TerraChem have exceptional experience having completed crude units, Delayed Cokers and FCC's including some of the worlds largest units. TerraChem will deploy a specialist engineer to integrate with the clients operations and T&I teams to plan the decon process in the finest detail to meet clients expectations in the shortest possible time. Please refer to our case studies for examples of this application.
With years of Refinery Process and Decontamination experience TerraChem are able to offer complete Project Management and Consulting Services to ensure the smooth running of your turnaround or indeed later process operations.

For Major Turnarounds and Shutdowns TerraChem can deploy a process specialist to integrate with the refinery operations and T&I teams to help plan the most effective and beneficial decontamination process. Drawing on years of international experience, expert advice can be provided not only on the decontamination process but also on the overall shutdown process to maximise safety and minimise the schedule.