Sustainable Oil Sludge Cleaning: Revolutionizing Sludge disposal
Are you still relying on outdated methods like heat for oil sludge cleaning? Consider a more sustainable alternative. Envorem introduces a groundbreaking solution that harnesses the power of water for oil sludge treatment and soil remediation.
Solution.
It’s all about water.
Oily sludge is a viscous, sticky mess. It is almost impossible to pump and is a hazardous waste that no-one wants.
The usual disposal routes for these wastes is incineration or dumping into open pits. However, pits just procrastinate the problem as the sludge will not go away and will eventually have to be incinerated generating colossal quantities of CO2 – around 1.5 tonnes per tonne incinerated.1
Envorem has developed an innovative new technology that uses a little-known phenomenon in water called cavitation to process production sludges, cleaning the solids and recovering the entrained oil - all without generating emissions.
We have completed a highly successful pilot in Oman for their National Oil Company (PDO) to treat sludge and oil-contaminated soil. The pilot proved the technology generates a fraction of the emissions of thermal treatment and is both cheaper & faster. 99% of the oil was removed from sludge as crude of usable quality - a double benefit; reducing the need for extraction and its associated carbon footprint, plus saving emissions from disposal by incineration. Furthermore, this demonstrated that if the value of recovered oil is included, costs are potentially net positive providing a financial as well as environmental case for change in practice.
So what’s the secret?
Well, you will understand that we don’t share too much even though our process is now patented but….
Envorem has combined established techniques with hydraulic shock and cavitation, where bubbles are created by the vaporisation of water, a phenomenon copied from the natural world2.
Cavitation can be generated ultrasonically, electrically or physically and is widely known as a parasitic effect that destroys propellers on ships and the impellers of pumps. The collapse of cavitation bubbles is so powerful it liberates fragments of metal from the surfaces.
Pump impeller with cavitation damage
Sounds incredible? Here is a link to a great video by Richard Hammond (Top Gear) explaining the power of cavitation.
Here’s another video showing cavitation in action. The power of cavitation can smash the bottom of a glass bottom clean off the main body.
Envorem harnesses these forces to create a water-based system that disassembles the sludge and strips oil contamination from particle surfaces. At the core of the system, millions of cavitation bubbles are artificially generated within the target material. These bubbles collapse with incredibly high forces, forming microscopic water jets and shock waves that impact surfaces of solids and generating localised temperatures of up to 3,000oC.
The great news is that because all cavitation occurs at a microscopic level, the energy is highly focussed making the process highly energy-efficient and really fast! As the hydrocarbons are physically removed rather than burnt, all this occurs without generating emissions. (Other than the small emissions from our energy usage).
A further benefit that is key to encouraging a change of practice by the oil industry, is that the oil is recovered and can be recycled3. This potentially makes adopting cleaner practices a profitable activity!
We have already tested our oil remediation technology processing at 50 tonnes sludge per hour - some 10 times the capability of thermal treatment plants and using 95% less energy4, all in a system that is small enough to be mobile; contained in several trucks. A fixed plant could easily be scaled to process 10-50 times this figure putting into viable reach some of the massive clean-up challenges the oil industry faces. And, with the process being relatively inexpensive there is no longer a reason not to do it!
Bench Scale Trial Results
The sand was cleaned to <1000PPM (10 times better than required by Oman standards)
One might imagine that the material is torn apart by the immense forces generated by cavitation, but the bubbles are small and their forces only affect the surfaces of the material being treated. It is this property that is causing scientists in the United States to investigate using cavitation as a gentle, non-chemical method to clean the surfaces of soft fruit.
Results: Weathered Sand From Kuwait
(sample provided by Kuwait Oil Company)
After (<0.1% oil)
Before (5%oil)
5% oil at the start and <0.1% TPH post-processing (10 times better than standard required)
Testing and results
Having proven the technology at bench scale, the system was then scaled up to a 50-tonne per hour test to verify performance at high throughput. Sludge for the trial was synthesised by making a sludge from 25% heavy fuel oil and fine sand. The oil was recovered and the TPH of the cleaned sand was less than 2000ppm (0.2%).
Subsequently, Envorem was awarded a pilot project in Oman as a field trial, processing sludge extracted from a pit and directly from tankers. Here is a picture of our Pilot project in Oman:
The equipment is built into 40ft transportable containers for plug & play set-up on site allowing it to be sited close to the waste source.
The results from the pilot were that:
The system operated at a steady state of 2 tonnes sludge or soil per hour
>99% of the hydrocarbons were recovered
Solids were cleaned to <5000 PPM TPH (standard required was 10,000)
Envorem’s new 5-20m3/hour pilot unit
Boardroom Action
As the world transitions away from fossil fuels, the Boardrooms of oil producers are understandably focused on minimising cost, improving efficiency, and diversifying into new “green energy” markets to maintain shareholder value whilst simultaneously addressing ESG challenges. Costs that reduce the bottom line are unwelcome.
This is where Envorem can
change the game
New Sludges
Before addressing legacy deposits, we must tackle the 120 million tonnes of new sludges produced annually. By embedding Envorem systems in crude oil production we can recover and return the oil from sludge to the production process before it becomes a byproduct for disposal.
The solids residue (around 10% of original sludge volume) is clean enough to be disposed of as non-hazardous waste1.
The system takes sludge and using its entrained water as process water, separated the unwanted solids and returns the fluids to production. Only the recovered solids leave the site by truck:
A schematic of how this could work
- Wet crude sent from wells
- Sludge from separators to be processed by Envorem in-line sludge system
- Processed crude to the refinery
- Produced water in
- Produced water out
- Recovered wet crude re-enters the system
- Non-hazardous1 solids to landfill
- Produced water sent for treatment
Preliminary figures2 suggest the benefit to the oil producer is:
- A 0.5% increase in production efficiency
- A 90% reduction in solid waste volume generated
- A reduction in sludge disposal costs of circa 40% (excluding oil value)
The environment benefits by:
- Elimination of pollution from sludge incineration or dumping
- A 0.5% reduction in the volume of oil extracted from the earth
- A reduction in the carbon footprint of oil production of circa 4%
All the technology is proven and we are ready to engage.
If you are an oil producer that wants to reduce your operating costs, improve production, reduce your environmental impact and lead not follow - then contact us!
Aged Sludges
Sludges in pits can be 20-60% recoverable oil. With processing rates of up to 100m3 per hour, Envorem provides an eco-friendly and affordable way to quickly get rid of these pits for good!
Oil lake from Kuwait
If the sludge has been cast into open pits as opposed to closed tanks, the oil will have degraded, leaving behind the heavier, less valuable fractions. In some cases it can be blended with lighter oils and recycled back into oil production - otherwise, it is only really good for sequestration into road coverings (Tarmac) or roofing tiles.
Still, any return from the waste will offset the cost, and Envorem’s technology is still substantially cheaper and kinder to the environment than incinerating the sludge - so still a win!
What Envorem offers is an opportunity for the industry to clean up its legacy sludges without generating emissions and at a lower cost than has ever been possible. Depending upon the age of the sludge and the value of the recovered hydrocarbons, the clean-up costs might be mitigated or even be cost positive.
The benefit to the environment is:
- The polluting sludge pit/lagoon is remediated without creating emissions
- The risk of leaching into the surrounding environment is removed
- The risk to wildlife is removed
- The carbon footprint, and risks associated with transporting the sludge to an incinerator, are eliminated
The benefits to the oil producer are:
- The legacy pollution is dealt with without creating emissions
- Envorem system is mobile, so sludge can be treated at source - no costly and risky transport to an incineration plant
- Costs of Envorem treatment are substantially less than incineration or thermal desorption
- The hydrocarbons are recovered potentially further offsetting costs
- Residual solid waste is non-hazardous1 and can be safely used for landfill (back into the pit the sludge came from)
Land Areas
In parts of the world, operations by the oil industry or civil unrest have caused large swathes of land to be contaminated with oil. Where the pollution is heavy, in-situ and bio methods can’t cope. Here, Envorem’s systems are unique, they can accept any level of oil contamination, solids content and water content.
The pictures below are from Libya, where tank farms have been destroyed, leaking millions of barrels of oil onto the land.
Ras Lanuf oil spill - estimated 240,000m3 contaminated soil
As Sidr oil spill - estimated 550,000m3 contaminated soil
Similar scenes are found in Kuwait, Iraq and huge areas in Canada from the tar sands operations. Digging up the contaminated soil, transporting it to a processing centre for incineration or other treatment is both costly and consumes huge amounts of energy, in just the excavation and transport alone. An additional complication is that in some areas, unexploded ordnance remains a factor.
Envorem is working on an exciting development we call “The Combine Harvester”. It works its way across large swathes of land, cutting to a depth of up to 1.8 metres in a single pass, processing the soil/sludge at a rate of 50 tonnes per hour and returning cleaned solids in its wake. A support train of containers on trucks recycle the process water. It is designed to be remotely controlled and able to sustain a blast from light ordnance. It is intended for use on both shallow “wet” lakes as well as dry deposits.
It’s too early to disclose further details but watch this space - this development will be a complete gamechanger. We will keep you up to date on our News page.
Scale
Envorem’s 25/100M3/hour unit ready for deployment Dec 2023
Adopting our technology allows the oil production sector to recycle its byproducts reducing carbon footprint, operating costs and, recovering materials for recycling. Our tested method can process up to 100 tonnes of wet sludge hourly, outperforming thermal treatment by 20X and using 95% less energy. It even uses the water in the sludge for cleaning the sludge itself! With compact mobile systems, our technology can scale up or down as needed.
We believe the power of our technology can be used to clean oily sludge from a whole range of sources and industries; we are looking forward to working with companies with the vision to clean up the world’s oil pollution.
Get in touch now and let’s discuss how we can work together for a cleaner planet!