Oil Water Separator
What is Oil Water Separator
An oil water separator (OWS) is a piece of equipment used to separate oil and water mixtures into their separate components. There are many different types of oil-water separator. Each has different oil separation capability and are used in different industries. Oil water separators are designed and selected after consideration of oil separation performance parameters and life cycle cost considerations. "Oil" can be taken to mean mineral, vegetable and animal oils, and the many different hydrocarbons.Oil water separators can be designed to treat a variety of contaminants in water including free floating oil, emulsified oil, dissolved oil and suspended solids. Not all oil separator types are capable of separating all contaminants.
Advantages of Oil Water Separator
Safeguarding equipment and machinery
One major benefit is equipment protection. Oil separators help safeguard equipment and machinery by removing oil contaminants from water. This extends the life of important assets and reduces maintenance expenses.
Driving cost efficiencies
Efficient oil separators lead to significant cost savings. They enable clean water discharge, meet environmental regulations, and reduce disposal and water treatment costs. Improved equipment efficiency also reduces downtime and increases productivity, which adds to overall cost efficiency.
Championing environmental preservation
The most significant benefit is environmental preservation. Oil separators are crucial for protecting aquatic ecosystems by stopping oil-contaminated water from entering natural habitats.
Reduce waste
Oil separators remove contaminants from wastewater, allowing it to be recycled or reused rather than wasted. This effectively reduces the risk of environmental contamination and helps to preserve natural resources, as well as reduce energy consumption.
Why Choose Us
Our Factory
In 2016,the company formally moved in to Renhe advanced manufacturing base in Yuhang District. The newly moved office area is spacious and bright with complete equipped facilities, which will greatly improve the office environment and work efficiency of all employees, create a good service environment for customers and enhance the company image.
Product Application
The products are widely used in electric power, shipbuilding, aerospace, electronics, metallurgy, machinery, automobile manufacturing, petroleum, chemical industry, textile, chemical fiber, light industry, paper-making, rubber, instrumentation, food, air separation, cigarette, medicine, biology, daily chemicals and other industries.
Production Market
We are sold well in more than 30 provinces and cities in China, and nearly 10000 users have played an active role in national key projects. The products have been exported to Pakistan in complete sets for many times West, Australia, Iran, India, Sudan, Indonesia, Vietnam, Saudi Arabia and other Southeast Asia, the Middle East, Central Asia and Africa.
Our Service
Strong and perfect after-sales service network, there are 9 customer service centers in major regions of China, each center has professional service engineers, a total of more than 50 people, quickly and timely solve problems in after-sales service, such as equipment start-up debugging and troubleshooting.
The Function Of Oily Water Separators
Delving deeper into operation
Oily water separators are a special type of oil separator designed very carefully to deal with complicated oil and water mixtures. They do more than just basic separation – they're good at capturing tiny oil droplets that regular methods can't handle.
Harnessing principles for separation
Oily water separators work based on basic science principles. Gravity, a natural force, helps separate oil and water because they have different densities. For instance, in air oil separators, centrifugal force separates oil from compressed air by creating surface tension.
There are also principles like coalescence and filtration at play. Coalescence means making small oil droplets come together into bigger ones so they're easier to remove. Filtration uses specially designed materials to catch these larger droplets effectively.
Ensuring cleaner water discharge
The main aim of oily water separators is to ensure that the water they release meets strict regulations. By effectively getting rid of even the tiniest bits of oil, these separators help create a cleaner, healthier environment. Whether in industries or marine use, oily water separators are crucial to responsible water management.
How Does an Oil Water Separator Work
Filtration stages
The oil containing condensate from a compressor flows under pressure into the separator. It moves through a first-stage filter, which is usually a pre-filter. A pressure relief vent typically helps reduce the pressure and avoid turbulence in the separator tank. This allows the gravitational separation of free oils.
First stage
First-stage filters typically consist of polypropylene fibers that adsorb the oil, but not the water. This means oil droplets will stick to the surface of the propylene fibers. Due to their oil-attracting characteristics, these are known as "oleophilic" fibers. This type of filtration media usually floats on the surface of the water. However, as it gets heavier, it adsorbs oil droplets, sinking deeper near the end of its service life.
The second and third stage
After the first-stage filtration, the condensate flows through the main filters. These include second-stage and sometimes third-stage filters. They often rely on activated carbon (or organoclay for stronger emulsions) to purify and "polish" the condensate. Essentially, depending on the type and size of the separator, condensate will undergo one or two consecutive stages of filtration with activated carbon/organoclay.
Last step
At the end of this process, the remaining oil residues in the condensate are collected. At an ambient temperature of 20℃ containing 1-2 g/m3 of oil after the first stage, there is around 2-3 mg/m3 of oil after separation.
The remaining water is sufficiently free from contaminants and can be safely discharged into the sewer system. The oil water separator has done its job. In the end, everybody benefits.
Construction of Oily Water Separator
Separator unit
This unit consists of catch plates which are inside a coarse separating compartment and an oil collecting chamber.
Here the oil has a density which is lower than that of the water, which makes the former rise into the oil collecting compartment and the rest of the non-flowing oil mixture settles down into a fine settling compartment after passing between the catch plates.
After a period of time, more oil will separate and collect in the oil collecting chamber. The oil content of water which passes through this unit is around 100 parts per million oil.
A control valve (pneumatic or electronic) releases the separated oil into the designated oil water separator sludge tank.
The heater may be incorporated into this unit for smooth flow and separation of oil and water.
A heater may be incorporated in this unit either in the middle or sometimes in the bottom part of the unit (depending upon the area of operation and capacity of the separator equipment) for smooth flow and separation of oil and water.
The first stage helps in removing some physical impurities to achieve fine filtration in the later stage.
The filter unit
This is a separate unit whose input comes from the discharge of the first unit.
This unit consists of three stages – filter stage, coalescer stage and collecting chamber.
The impurities and particles are separated by the filter and are settled at the bottom for removal.
In the second stage, the coalescer induces a coalescence process in which oil droplets are joined to increase their size by breaking down the surface tension between oil droplets in the mixture.
These large oil molecules rise above the mixture in the collecting chamber and are removed when required.
The output from this unit should be less than 15 ppm to fulfil legal discharge criteria.
If the oil content in water is more than 15 ppm, then maintenance work such as filter cleaning or renewal of filters is to be done as required.
Oil content monitor and control unit
This unit functions together in two parts – monitoring and controlling.
The ppm of oil is continuously monitored by Oil Content Monitor (OCM); if the ppm is high, it will give an alarm and feed data to the control unit.
The control unit continuously monitors the output signal of oil water separator, and if an alarm arises, it will not allow the oily water to go overboard by operating a 3-way solenoid valve.
There usually are three solenoid valves commanded by the control unit. These are located in the first unit oil collecting chamber, second unit oil collecting chamber and one on the discharge side of the oily water separator, which is a 3-way valve.
The 3-way valve inlet is from the oil water separator discharge, where one outlet is overboard and the second outlet is to the oil water separator sludge tank.
When oil water separator gives an alarm, the 3-way valve discharges the oily mixture in the sludge tank.
Treatment of stormwater
Treatment of stormwater helps the environment by retaining stormwater and slowly releasing it so as not to contribute to excess runoff and erosion, and by removing suspended solids from the water.
Treatment of food industry wastewater
Wastewater is one of the byproducts of the food industry, and this water contains oil, grease, and other suspended solids that must be removed so as not to clog up the municipal wastewater system.
Treatment of industrial wastewater
Industrial wastewater treatment is another application in which oil water separators are needed. An example would be bulk petroleum storage and handling, and industrial activity that generates large quantities of oily wastewater. Whether it's for everyday use or cleanup of water in contaminated sites, can meet your industrial wastewater treatment needs.
Choosing the right oil water separator can seem daunting. Just as not all applications are alike, not all separators are made alike.
A crucial distinction to make is the one between oil water separators, interceptors and traps. Not all products marketed as separators actually live up to the name. Many are only interceptors or traps. These may seem to be solid choices, but because they only contain baffles or weirs, they will trap surface oil but won't actually separate any oil that has mixed with water below the surface. What may have seemed to be a good deal turns out to be an overpriced and ineffective product that can lead to discharges in excess of the legal hydrocarbon discharge limits.
Enhanced Coalescing Oil Water Separators are true oil water separators. Our media is capable of removing essentially all free and dispersed non-emulsified oils to an effluent concentration of less than 5 ppm. Our proprietary design incorporates patented revolutionary non-plugging polypropylene coalescing plates that meet the more stringent European Union Standard. This requires a discharge limit of less than 5 ppm of oil and grease from an influent concentration of 2,000 ppm. If required, we can provide analysis, which indicates that, at the calculated overflow rate, the separator will be provided with the required square feet of projected plate separation area to achieve the specified performance under laminar flow.
Maintenance on separators is simple. There are no requirements for electricity, and our coalescing media can be cleaned with a standard hose or pressure washer. A manual side port is included in all of our above ground units to enable users to easily extract separated oil from within the unit. Solids can be easily drained from bottom ports.
Why Would You Choose an Above Ground Oil Water Separator Vs. A Below Ground Oil Water Separator
In many cases, a below ground oil water separator is the best option due to space restrictions and layout. You can use gravity to drain into a below ground system and then into the sanitary sewer system so there is no need for pumps and controls. In other cases, a below ground system has been previously specified and it is not possible to change the specifications.
Some of the issues involved with a below ground system are that they are often forgotten after installation – one of those “out of sight, out of mind” matters. That is fine if there is only oily water going through the system. Troubles start when sediment and solids are introduced into the oil water separator. As the solids build up within the separator, the efficiency decreases. If the solids and oil are not removed from the separator, it will eventually fill up to the point that the separator will not separate the oil, but just pass the oil through with the water. Periodic maintenance on below ground separators, which includes pumping out the oil and sludge, is critical to their efficient long-term operation.
Finally, due to poor maintenance or bad soil conditions, if an underground system leaks, the potential clean-up costs can be very expensive! While most underground tanks are double walled, very few underground piping systems are, which is another source of potential leaks into the ground water. The longer the system remains underground, the more potential for leaks and the larger the potential liability.
Oil Water Separator Maintenance
An oil water separator needs to be properly and regularly maintained to stay in good working order. When these devices are not drained and cleaned out religiously, oils and other debris will stop them up and make them useless. This can cause the levels of oil in the released water to go beyond the effluency limits indicated.
Models of oil water separators that sit above the ground are somewhat easier to keep clean since everything is easy to get to. This is because there are no tight spaces and plates can be easily taken out, cleaned and replaced. All above-ground types can be maintained from the ground level. Also, solid waste can easily be removed via a large opening at the ground level.
If using a below ground oil water separator, it is particularly essential that you follow a strict schedule of maintenance. Because the unit is underground where it can’t be seen, it is far more likely that you will forget to clean it. Here are the maintenance procedures to follow for this type of oil water separator.
After one month of use, make sure you inspect and clean the inlet area in the following way:
Turn off the influent water to the unit.
Open the unit cover.
Remove any oil and dispose of it in a way that complies with company and legal procedures.
Drain the water from the separator.
Measure the depth of the leftover solids and write it down. This will serve as a framework for scheduling future maintenance and cleaning.
If necessary, dispose of the solids.
After doing all of this, you will need to clean the media plates. They can be cleaned while still in the unit or removed for cleaning. To clean them without removal, stick a low pressure hose in between the plate spaces on the plate packs. Any dirt flushed from the plates should be removed through the drain on the hopper outlet.
For cleaning the plates outside of the oil water separator, rinse them down with a low pressure hose while taking extreme care to avoid getting the discharge on the ground where it has access to groundwater. All that needs to be removed is the sludge and oil buildup.
When this is done, check the tank for damage and repair the internal coating if needed. To start the separator again, just place the plate packs back into the unit as they were before. Ensure that they are securely installed to prevent them from floating when the unit resumes functioning. Maintenance should be carried out regularly by a qualified professional, depending upon the unit’s application and the amount of oil and other debris accumulated.
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