APPLICATION
Hydrocarbon Leak Detection
Oil leaks are a common cause of plant failure. With condition monitoring any leaks can be addressed before any major damage to plant is caused.
Products
Oil leaks into water systems are one of the most common causes of equipment damage and unplanned downtime across marine, offshore and industrial operations. With continuous oil in water monitoring, hydrocarbon ingress can be detected as soon as it occurs, allowing operators to act before damage escalates or contaminated water is discharged.
Rivertrace oil in water monitors are used across a wide range of hydrocarbon leak detection applications, from heat exchanger tube failure detection in cooling water systems to hydrocarbon ingress monitoring in industrial process water circuits.
| Key thing to remember
Hydrocarbon leak detection in water systems relies on continuous online monitoring, not periodic grab sampling. A leak that develops between manual samples may go undetected for hours or days. Continuous oil in water monitoring provides real time detection and alarm, enabling operators to intervene immediately when hydrocarbon ingress occurs. |
What Is Hydrocarbon Leak Detection in Water Systems?
Hydrocarbon leak detection in water systems refers to the continuous monitoring of water circuits for the presence of oil, fuel or other hydrocarbon contaminants. An oil in water monitor is installed in the water circuit and measures the hydrocarbon concentration of the water in real time.
When hydrocarbons enter the water circuit through a leak or equipment failure, the oil in water monitor detects the increase in hydrocarbon concentration and activates an alarm. This alerts operators to the leak before significant contamination can occur, and where connected to process controls, can trigger an automatic response such as isolating the affected circuit or stopping a discharge.
The approach is fundamentally different from periodic grab sampling, which only provides a snapshot of water quality at the moment the sample is taken. Continuous monitoring ensures that any hydrocarbon ingress is detected in real time, regardless of when it occurs.
How Do Hydrocarbons Enter Water Systems?
Hydrocarbons can enter water systems through several different failure modes, each of which presents a different detection challenge:
Heat exchanger tube failures
Heat exchangers cool process fluids, lubricants, fuel and hydraulic oil by transferring heat through a tube wall to the cooling water on the other side. A cracked or corroded tube allows the hydrocarbon fluid to cross the barrier and contaminate the cooling water circuit. This is one of the most common sources of hydrocarbon ingress in marine engine rooms and industrial plants.
Mechanical seal and gasket failures
Rotating machinery including pumps, compressors and turbines uses mechanical seals to prevent oil from entering adjacent water circuits. Worn or failed seals allow lubrication oil, hydraulic oil or process fluid to leak into the water system. This type of leak often develops gradually, making early detection particularly important.
Pipe and fitting failures
Corrosion, erosion, vibration fatigue and mechanical damage can cause failures in pipework and fittings carrying hydrocarbons in proximity to water systems. Where hydrocarbon and water circuits share a common sump, bilge or drainage point, a pipe failure can introduce hydrocarbon contamination into the water stream.
Storage tank drainage
Water condensed during the storage of hydrocarbon fuels accumulates in the base of storage tanks over time. This water must be periodically drained, but the drainage water contains dissolved and dispersed hydrocarbons. Oil in water monitoring at the drainage point confirms that the hydrocarbon content is within acceptable limits before the water is discharged.
What Are the Consequences of Undetected Hydrocarbon Leaks in Water Systems?
If hydrocarbon ingress into a water system is not detected and addressed promptly, the consequences can be significant:
- Equipment damage — hydrocarbons in cooling water reduce heat exchange efficiency and can degrade seals, gaskets and other components in downstream equipment
- Boiler contamination — if contaminated cooling water enters a boiler feed water circuit, oil ingress can cause heat transfer surface fouling, tube overheating and boiler damage
- Environmental non-compliance — if contaminated water is discharged overboard or to a watercourse without detection, it may constitute a breach of environmental permit conditions or MARPOL requirements
- Unplanned shutdown — undetected hydrocarbon leaks can escalate from a minor seal failure to a major equipment problem, causing costly unplanned downtime
- Safety risk — in certain process environments, hydrocarbon contamination of water systems can create fire or explosion risk
| The cost of late detection
A heat exchanger tube failure that is detected immediately can be isolated and repaired with minimal disruption. The same failure left undetected for days can result in widespread contamination of the cooling water circuit, damage to downstream equipment and environmental enforcement action if contaminated water has been discharged. Continuous monitoring is the most cost effective form of protection. |
In Which Applications Is Hydrocarbon Leak Detection Used?
Oil in water monitoring for hydrocarbon leak detection is used across a wide range of water systems in marine, offshore and industrial environments. The table below summarises the most common applications.
| Application | Water system | How detection works |
| Heat exchanger leak detection | Cooling water circuit | Oil or process fluid crosses a failed tube wall into the cooling water; detected at the cooling water outlet |
| Lubrication oil leak detection | Engine cooling water or jacket water | Worn seals or cracked casings allow lube oil to enter the water circuit in engines, turbines and compressors |
| Fuel oil leak detection | Cooling water from fuel oil coolers | A failed fuel oil cooler tube introduces fuel oil into the cooling water circuit |
| Hydraulic oil leak detection | Process water or cooling water circuit | Hydraulic system failures introduce hydraulic fluid into water circuits in offshore and industrial plants |
| Hydrocarbon storage tank monitoring | Tank drainage water | Water condensed in hydrocarbon storage tanks accumulates hydrocarbon contamination that must be detected before drainage or discharge |
| Process water monitoring | Industrial process water systems | Hydrocarbon ingress from failed seals or heat exchangers is detected in process water before it reaches a discharge or reuse point |
Which Rivertrace Product Is Right for Hydrocarbon Leak Detection?
The right product depends on the operating temperature and pressure of the water system, the type of hydrocarbon most likely to be present and the measurement range required.
| Product | Best fit application | Key capability |
| SMART 50M | Hydrocarbon leak detection in high temperature and high pressure water systems across marine and industrial applications | Versatile oil in water monitor designed for demanding temperature and pressure environments; detects hydrocarbon ingress in cooling water, process water and heat exchanger circuits |
| OCD Xtra | Hydrocarbon leak detection where calibration against specific oil or fuel types is required, or where a broader measurement range is needed | Measures oil accurately across 0 to 200ppm; factory calibrated on up to six oil types; adjustable onsite against laboratory analysis |
| OCD CW | Hydrocarbon leak detection in cooling water systems and lower pressure water circuits | Simple, robust oil in water monitor purpose designed for cooling water and process water applications; reliable measurement of hydrocarbon ingress from heat exchanger failures |
Where hydrocarbon leak detection is required specifically in a cooling water circuit, see the cooling water monitoring application page for more detail on the specific monitoring considerations for cooling water systems.
What Should You Consider When Specifying a Hydrocarbon Leak Detection Monitor?
Before selecting an oil in water monitor for a hydrocarbon leak detection application, confirm:
- What is the operating temperature and pressure of the water at the monitoring point?
- What type of hydrocarbon is most likely to enter the water system in the event of a leak?
- What concentration of hydrocarbon should trigger an alarm?
- Does the monitor need to interface with an isolation valve or process control system for automatic response?
- Is continuous online monitoring required, or is periodic verification sufficient for the application?
- Is the installation location in a classified hazardous area requiring ATEX or IECEx certification?
- What space and access constraints apply at the monitoring point?
- What calibration and maintenance access is available?
| Early detection is the key benefit
The value of oil in water monitoring for hydrocarbon leak detection lies in detection speed. A monitor that detects a leak within minutes of it occurring gives operators the opportunity to isolate the failed component before contamination spreads. The same leak detected by a weekly grab sample has already contaminated the water circuit for days, with all the associated equipment and environmental consequences. |
In Which Industries Is Hydrocarbon Leak Detection Monitoring Used?
Rivertrace hydrocarbon leak detection solutions are used across a range of industries where hydrocarbon and water systems operate in close proximity:
- Marine vessels including cargo ships, tankers, passenger vessels and naval vessels with engine room cooling systems and fuel oil coolers
- Offshore platforms and FPSOs with process cooling systems, gas compression cooling and hydraulic power unit cooling circuits
- Power generation plants where steam condenser tube failures can introduce turbine oil into the cooling water
- Chemical and petrochemical plants with process cooling systems where heat exchanger failures introduce process hydrocarbons into cooling water
- Refineries with crude oil and product cooler circuits where tube failures are a recognised contamination risk
- Hydrocarbon storage facilities where tank drainage water must be monitored before disposal
- Industrial compressor stations where lube oil contamination of cooling water is a known operational risk
Frequently Asked Questions
What is hydrocarbon leak detection in water systems?
Hydrocarbon leak detection in water systems is the continuous monitoring of water circuits for the presence of oil, fuel or other hydrocarbon contaminants introduced by equipment failures such as heat exchanger tube failures, seal failures or pipe failures. An oil in water monitor installed in the water circuit detects hydrocarbon ingress in real time and activates an alarm to enable immediate corrective action.
What causes hydrocarbons to enter cooling water systems?
The most common cause is a failed tube in a heat exchanger or cooler, which allows oil, lubricant, fuel or process fluid to cross the tube wall barrier into the cooling water. Other causes include worn mechanical seals in rotating machinery, pipe or fitting failures in hydrocarbon systems adjacent to water circuits, and corrosion or erosion damage to heat exchanger components.
Why is continuous monitoring better than periodic grab sampling for hydrocarbon leak detection?
A periodic grab sample only reflects the water quality at the moment the sample is taken. A hydrocarbon leak that develops between samples may go undetected for hours or days, during which time it can cause equipment damage, process disruption or environmental non-compliance. Continuous online monitoring detects any increase in hydrocarbon concentration immediately and activates an alarm in real time.
Which Rivertrace product is suitable for heat exchanger leak detection in a cooling water system?
The SMART 50M is suitable for high temperature and high pressure cooling water applications across marine and industrial installations. The OCD CW is a simpler, more compact option for lower pressure cooling water circuits. The OCD Xtra is suited to applications where the type of hydrocarbon varies or where calibration against a specific oil type is required.
Can a hydrocarbon leak detection monitor be connected to an automatic isolation valve?
Yes. Rivertrace oil in water monitors can interface with isolation valve controls via relay outputs, so that a confirmed high hydrocarbon alarm automatically closes a valve to isolate the affected water circuit or stop a discharge. This enables an automatic protective response before operators have physically responded to the alarm.