On this page, we’ve compiled the most common questions about our technologies, customer process, and operations. You can jump to the section that interests you by clicking on the following categories:
Operating principle, differences from other methods, process conditions, applicable metals and industries.
Chemical properties, dosage, effect on lime consumption, price, purchasing, and delivery methods.
Effects on metals, salts, and pH, as well as the discharge of treated water into the environment and its use as drinking water.
Precipitate, metal recycling & Green Zone
Sludge settling, composition, utilization, metal recycling and Green Zone products.
Water samples, Lab PoC programs and price, pilot testing, water and sludge analyses.
Price and delivery time of plants, integration into the existing process, design, equipment, automation, and monitoring.
Environment, permits & certifications
Environmental impacts, emissions, required permits, and quality and environmental certifications.
HQ, team, visits, company and technology background, patents, references, partners, and questions from our customers.
EPSE™ Method and its applications
How does the EPSE™ Method function?
In the EPSE process, the EPSE 1010 chemical is added to the low-pH aqueous phase according to a formula determined in the laboratory, after which the pH is raised to the desired level using the most appropriate base for each specific case, such as lime milk or sodium hydroxide (lye). The process precipitates all dissolved heavy metals at once. The EPSE™ Method functions as a practical process similar to traditional chemical precipitation.
What are the benefits of the EPSE™ Method compared to our current solution?
The EPSE™ Method does not necessarily replace the current process, but often complements and enhances it. For example, our customers have achieved improved metal removal efficiency, lower chemical consumption, reduced sludge volume, and opportunities for metal recovery. Each site is evaluated through laboratory testing and pilot studies before any investment decisions are made.
How does the EPSE™ Method differ from lime precipitation?
Although the process is technically almost identical to conventional hydroxide precipitation, the EPSE™ method differs significantly from lime precipitation in chemical terms; the metals do not precipitate as conventional hydroxide sludge, but rather as an insoluble multi-metal complex.
In addition, the EPSE™ Method increases the efficiency of water treatment. We have many examples of wastewater where EPSE treatment has dramatically reduced lime consumption—by as much as 70% compared to traditional lime precipitation. Particularly in multi-metal process waters, the precipitation chemistry of amphoteric metals in EPSE treatment typically improves efficiency and reduces lime consumption. However, lime consumption must always be determined on a case-by-case basis, as the chemistry of each wastewater stream is unique and many factors influence lime consumption.
Which industries benefit most from EPSE technology?
EPSE technology is particularly well-suited for industries where dissolved metals are present in water. These include, for example, the mining industry, metal processing, metal coating, the battery industry, electronics manufacturing, waste treatment, the recycling of ash and slag materials, and many processes in the chemical industry.
For what size volumes is this technology suitable?
The EPSE™ Method is a chemical process, and the treatment volume is limited only by technical factors, such as available equipment and facilities. When optimized, the chemistry works exactly the same way for a flow of one cubic meter as it does for a flow of thousands of cubic meters.
Is this technology suitable for municipal wastewater treatment?
The EPSE™ process removes dissolved metals from wastewater, but not, for example, organic matter. Municipal wastewater typically contains only small amounts of metals, so EPSE treatment offers no significant benefit in the treatment of municipal wastewater.
Is the EPSE™ Method a selective process?
No, EPSE technology is not selective; instead, the process precipitates all metals dissolved in water. If the water contains high concentrations of metals of interest for recovery, recovery is possible from the solid fraction—that is, the multi-metal sludge generated by the EPSE process.
What is co-precipitation?
In co-precipitation, a more soluble compound precipitates primarily along with the primary precipitating compound under conditions in which it would not precipitate as a pure compound. This can be utilized to reduce the concentrations of soluble metals in solutions. Co-precipitation occurs through several different mechanisms, such as adsorption onto the surface of the precipitate, crystallization into the crystal lattice of the primary precipitate, or the formation of inclusions, in which the co-precipitating substance remains trapped within another solid. Co-precipitation is promoted when the specific surface area of the primary precipitating compound is large.
Which metals are affected by EPSE treatment?
The EPSE treatment affects all metals dissolved in water, but the treatment results vary on a case-by-case basis. On our EPSE™ Method page, you’ll find a list of metals for which our method has been tested.
How do variations in wastewater composition affect the technology’s effectiveness?
The EPSE™ method is not sensitive to even large fluctuations in metal concentrations, but it is important to take potential variation ranges into account when designing a process formula in order to find the most cost-effective solution. Once EPSE technology has been implemented at a specific facility, it is advisable to closely monitor the process initially to ensure that the concentration limits specified in the environmental permit are reliably met and that the technology operates as intended. EPSE provides comprehensive technical support during this phase.
Does water temperature affect the effectiveness of the treatment?
The EPSE™ method has proven effective over a wide temperature range, and normal fluctuations in process temperatures generally have no significant effect on treatment efficiency.
Does EPSE processing work in the textile and other industries?
EPSE can address challenges across a wide range of industries, such as mining, metals, textiles, and paints. Check out these articles on the application of EPSE technology in various industries.
- Many opportunities of the EPSE™ Method – Red Mud
- Many opportunities of the EPSE™ Method – Textile wastewater
Is this method suitable for the treatment of solid waste, such as fly ash?
Yes, but applying the EPSE™ Method requires mixing the solid fraction with the liquid to form a slurry, so that chemical reactions can take place. We’d be happy to discuss the processing of different fractions on a case-by-case basis; please contact us, for example using our contact form.
Is the EPSE™ Method suitable for gas treatment?
The EPSE™ Method is not designed for gas purification. The EPSE™ Method is intended for the removal of metals from aqueous solutions and can also be used for the stabilization of metal-containing solids.
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EPSE 1010 chemical
What is EPSE 1010?
EPSE 1010 is a colorless, odorless chemical that occurs naturally on Earth. Our customers receive a safety data sheet with their chemical shipments for use in their own safety training.
What are the typical dosages for EPSE 1010?
The dosage of EPSE 1010 is always determined on a case-by-case basis during EPSE Lab PoC testing and optimized to be as low as possible.
How does the EPSE™ Method affect lime consumption?
We have many examples of wastewater where EPSE treatment has dramatically reduced lime consumption—by as much as 70%—compared to treatment without the EPSE™ method. Especially in multi-metal process waters, the precipitation chemistry of amphoteric metals in EPSE treatment typically improves efficiency and reduces lime consumption. However, lime consumption must always be determined on a case-by-case basis, as the chemistry of each wastewater stream is unique and many factors influence lime consumption. Read more from our expert article on base selection.
How much does the EPSE 1010 chemical cost, and where can I buy it?
The EPSE 1010 chemical is supplied as part of the license agreement. The price of the technology license is determined on a case-by-case basis according to the volume to be treated. If you are already using the EPSE™ Method at your site and would like to order more of the chemical, please contact your account manager or use the contact form.
In what form is EPSE 1010 supplied?
EPSE 1010 is typically supplied to smaller operators as a solid powder in 25-kilogram containers. For larger facilities, the chemical can be supplied, for example, in big bags.
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Quality and uses of the treated water
How does EPSE treatment affect the salts in water?
The EPSE™ Method is designed for the removal of metals. However, every wastewater stream is unique, and the specific contaminants that precipitate along with the metals depend on the chemical composition of the individual wastewater stream. Typically, for example, sulfate and chloride concentrations decrease during EPSE treatment, but each wastewater stream must be tested on a case-by-case basis before reliable conclusions can be drawn about the effects of EPSE technology on salts.
Does EPSE technology affect sulfate, chloride, and halide concentrations?
The removal of sulfates, chlorides, and halides from aqueous solutions is not a primary objective of EPSE technology. Nevertheless, tests have shown a significant reduction in high sulfate concentrations as a result of the treatment. In the EPSE™ process, sulfate concentrations have generally been observed to decrease to a level of 1,000–2,000 mg/L. Chloride levels have also been observed to decrease during treatment, but the concentrations of residual chlorides are generally significantly higher.
What is the end-pH of the treated water?
The pH of the treated water depends on the specific characteristics of each wastewater stream and the treatment objectives. In the process, the water’s pH is raised from acidic to alkaline or slightly alkaline levels to precipitate metals. However, unlike in lime precipitation, for example, it is safe to adjust the final pH of EPSE-treated water at the end of the treatment without the metals dissolving back into the water.
Can treated water be released into the environment?
Each facility’s environmental permit specifies the emission limits that the EPSE treatment process aims to achieve. Once these limits are met, the water can be discharged into the environment.
Is EPSE-treated water safe to drink?
No, not without further treatment. The wastewater generated by EPSE treatment is typically industrial water intended for recycling as process water. If the goal is to produce drinking water, other technologies—such as reverse osmosis (RO) and disinfection—are typically required in addition to the EPSE™ process.
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Sludge, Metal Recycling, and the Green Zone
How does EPSE technology affect sludge settling?
We have conducted hundreds of tests on a laboratory and pilot scale, and based on these results, the EPSE™ Method often appears to accelerate sludge settling. The resulting multi-metal sludge is typically heavier than conventional hydroxide sludge, and thus its settling rate can be significantly faster than would be possible without EPSE treatment. However, the sludge settling rate is always tested on a case-by-case basis, and our laboratory always performs so-called SSR (Sludge Settling Rate) tests as part of the Lab PoC testing of samples. This allows us to calculate the actual settling rate, which can be used, for example, to determine the size of settling tanks. Read more in our expert article about removing metals using chemical precipitation.
What is the composition of the EPSE precipitate?
The composition of the EPSE sludge always depends on the properties of the water, such as contaminant concentrations. The sludge composition can be determined during the EPSE Pilot Proof of Concept (PoC) testing, as the EPSE Lab PoC process typically does not produce enough sludge to determine its composition. See also our expert article about metal precipitation.
What can you do with EPSE precipitate?
The EPSE precipitate is very poorly soluble, and its disposal or reuse depends on the specific objectives, properties, and quantities of the sludge in each case. If the sludge contains significant amounts of valuable or critical metals, such as copper or silver, recovering them may be cost-effective. This requires a case-by-case assessment, and in some cases, disposal in a landfill is the most cost-effective option. After EPSE treatment, no metals are released from the sludge, so it may be possible to dispose of it in a regular landfill rather than a hazardous waste landfill.
How is metal recovery possible?
Recycling metals from solid, multi-metal scrap generated during processing is possible using various metallurgical methods. While the recycling of any metal is technically feasible, economic feasibility is influenced by a wide range of factors, such as the demand for that metal, its market price, its concentration, and the technical complexity of the required processing.
Can EPSE help with the reuse of old tailings, slag, or waste rock piles?
Yes. EPSE evaluates materials from both an environmental and a resource perspective. Many historical waste streams may still contain valuable metals, critical minerals, or other recoverable components. The goal of the Green Zone concept is to assess the technical, environmental, and economic recovery potential of materials on a case-by-case basis.
What is the Green Zone?
Green Zone transforms waste and byproducts into new, marketable products and strives to minimize the amount of waste sent to landfills. Learn more: Green Zone
What products does Green Zone manufacture?
Green Zone is a circular economy platform based on the utilization of by-products and waste streams to turn waste into value, in accordance with zero-emissions principles. Green Zone’s products are determined based on the specific raw materials available in each case: the process aims to maximize value by producing high-value products whenever possible. For example, critical raw materials or valuable metals can be extracted from old tailings or slag, after which suitable products—such as soil amendments, raw materials for the construction industry, or customized soil materials—are produced based on their mineralogical composition.
Why should metal removal be viewed as an opportunity rather than a cost?
Many metal-containing waste and by-product streams contain valuable or critical raw materials. EPSE’s approach is based on the idea that environmental challenges can also be viewed as opportunities for resource recovery and business. The goal is not only to purify water but also to identify opportunities for material recovery.
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Laboratory testing and piloting
Why is it worth conducting an EPSE Lab PoC (Laboratory Proof of Concept)?
The EPSE Lab PoC is the fastest and most cost-effective way to determine the suitability of the EPSE™ Method for a specific process before making major investment decisions. Through testing, it is possible to evaluate metal removal efficiency, chemical consumption, sludge volume, potential emission reductions, and economic benefits using real process data.
What does EPSE Lab PoC entail?
The EPSE Lab PoC is described in detail: EPSE Lab Hub.
Why are water samples needed?
Every type of wastewater and process water is unique, and even waters from different processes within the same facility are not identical to one another. Water samples are needed to determine the baseline conditions, test the EPSE treatment, and evaluate the results. Without samples, relying solely on data allows for preliminary estimates, but without testing in a laboratory or pilot plant, no certainty regarding the results can be guaranteed.
Why send water samples to EPSE specifically?
Laboratory testing is the fastest and most cost-effective way to determine whether current water treatment processes can be improved. A small-scale testing program can identify significant savings, emission reductions, or opportunities to create new value from waste streams.
How much does EPSE Lab PoC cost?
The price of the EPSE Lab PoC is determined based on the scope of testing and is agreed upon on a case-by-case basis.
What types of analyses can EPSE Laboratory perform?
Information about the EPSE laboratory is available on the EPSE Lab Hub page. If you are interested in testing a specific analyte or problem, please contact our laboratory manager or use our contact form.
Can the solubility properties of sludge be tested?
Yes, we can. Our laboratory has been accredited to perform solubility tests for several years now (SYKEre 40/2020), and we conduct them in accordance with European and Chinese standards, for example. For testing other properties of the ore, such as its mineralogical structure, we are currently relying on the assistance of our partners and other research laboratories.
What does a typical EPSE pilot look like?
The EPSE™ method can be piloted on both a laboratory and an industrial scale, and pilot solutions are always tailored to each customer. You can find comprehensive information about EPSE piloting here.
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Facilities, Implementation, and Services
Can the EPSE™ Method be implemented in an existing facility?
Often, yes. Implementing the EPSE™ Method in an existing facility is always our primary goal: we strive to complement and optimize existing systems whenever possible. Sometimes existing equipment is not suitable for EPSE technology as-is, but implementation is possible with minor modifications. However, if the equipment is nearing the end of its service life or has critical deficiencies, building a completely new plant or installing new equipment may be the most cost-effective option.
How does EPSE technology work in conjunction with membrane filtration techniques?
When using membrane filtration techniques such as reverse osmosis (RO) or nanofiltration (NF), it is essential that the water fed to the membranes be chemically compatible with the membranes so that the membranes’ filtration efficiency—and thus their service life—remains as high as possible. The EPSE process precipitates all soluble metals from the water and, at the same time, can remove a significant portion of substances such as sulfates. This, in turn, can improve the efficiency of membrane filtration, which is often an optional final step in the water treatment chain, depending on discharge limits or water recycling targets.
Can EPSE help reduce wastewater treatment costs?
In many cases, yes. Cost savings can result, for example, from lower chemical consumption, reduced sludge volume, lower final disposal costs, water recycling, or metal recovery. The final impacts are always determined on a case-by-case basis based on testing.
Do you provide plant design and equipment?
Our team consists of experienced plant design experts, and we deliver the EPSE solution in the way that best suits the customer’s needs—for example, as plant design or on a turnkey basis.
Is EPSE technology available as a turnkey solution?
Yes, it is.
How much does an EPSE facility cost?
The price of an EPSE plant depends on the specific implementation of the project. We offer a comprehensive range of solutions, from small plants processing a few cubic meters per hour to the retrofitting of existing treatment plants, and even EPC (Engineering, Procurement, Construction) projects. We can typically provide a cost estimate no sooner than after the completion of the EPSE Lab PoC testing program; however, with sufficient initial data and by comparing it to our previous projects, we can also provide a rough estimate of the plant’s cost at an earlier stage.
How quickly can the economic benefits of the EPSE project be assessed?
The assessment of economic potential typically begins as early as the Lab PoC phase. Through testing, it is possible to evaluate, for example, chemical savings, changes in sludge costs, water recycling opportunities, and the potential for metal recovery. This provides genuine data from the customer’s own process to support investment decisions.
How quickly can the EPSE™ Method be implemented?
The implementation timetable depends on the specific project. In the simplest cases, the technology can be integrated into an existing process with relatively minor modifications. Often, the first laboratory results are available well before the actual investment decision is made.
What is the delivery time for the EPSE Facility?
The delivery time for an EPSE facility depends on the agreed implementation type and, naturally, on geographical factors such as location and the reliability of supply chains. Our local partners, for example in Asia, Africa and the United States, help us not only to estimate delivery times but also to complete projects within the estimated timeframe.
How easily can the EPSE™ Method be automated?
The EPSE process can be easily automated, either partially or fully, in accordance with customers’ requirements. For example, in our Mobile EPSE™ pilot unit, the automated dosing of chemicals is based, amongst other things, on pH measurements taken at various stages of the process. In Mobile EPSE™ units, water pumping and sludge separation are also automated using tank level measurement, flow meters and other process parameters.
How is the effectiveness of the EPSE™ method monitored?
The effectiveness of the EPSE™ method is monitored by tracking the parameters defined at the time of implementation, which may include, for example, the concentrations of certain indicator metals in the treated water, visual observations or even the pH.
How is the EPSE process monitored?
The EPSE process can be monitored in a variety of ways, either automatically or manually. The efficiency of the treatment should be monitored by taking samples of the treated water. The operation of the process itself can be monitored automatically, for example, using pH and turbidity meters.
What other services does EPSE offer?
EPSE always takes a case-by-case and holistic approach to the customer’s plant, process or water system. We aim to ask specific questions and identify what kind of solution will deliver the best efficiency for the client, and which factors – such as emission limits or savings targets – are most important for the final implementation. We refer to this assessment as a ‘Desktop Assessment’, and we refine our findings through laboratory and pilot testing. We then provide a solution based on our best expert judgement.
EPSE Oy specialises in the treatment of metal-containing wastewater using its patented technology, the EPSE™ Method, whilst the US-based company EPSE Technology Inc. has extensive experience and intellectual property rights (IPR) relating to the treatment of solids and the efficient recovery of valuable metals. Our partners around the world provide support, for example, in the broader field of water treatment technologies and plant design, enabling us to offer comprehensive solutions.
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Environment, licences and certificates
Is EPSE a ‘green’ solution?
We avoid any form of greenwashing and calculate the impacts of the EPSE™ Method only on a case-by-case basis, based on tests and experiments carried out in the laboratory or in pilot studies. However, in several of our projects we have achieved significant, impressive results from impact assessments; read more here: Emissions reduction potential of the EPSE™ Method.
How does EPSE take environmental and sustainability issues into account?
Our entire technology is based on protecting the environment from harmful dissolved metals. Water treatment in the mining and other industrial sectors is a wide-ranging field involving numerous environmental and sustainability factors, such as emissions, chemicals and their manufacture, transport and use, water recycling, energy consumption, the carbon footprint of equipment and consumables, the social acceptability of the industry, working conditions, ensuring occupational safety, and legislation, compliance with which is monitored. EPSE is committed to responsible business practices and, as a Finnish company, complies with Finnish law. We always strive to design our solutions with the environment and people’s well-being as our top priority, which is often made possible by economic efficiency.
Can EPSE help us meet increasingly stringent environmental requirements?
Yes. The EPSE™ Method has been developed specifically for the removal of dissolved metals from water. Many of our customers are looking into this technology precisely when emission limits are becoming stricter or when their current solution no longer provides a sufficient safety margin in relation to the requirements of their environmental permit.
What emissions are produced by the EPSE™ Method?
The EPSE process produces metal-free effluent and a sparingly soluble multi-metal precipitate. During laboratory testing, we aim to meet the client’s targets – for example, regarding the metal concentrations in the treated water – and these are reported in full in our laboratory report.
Does EPSE reduce carbon dioxide emissions?
The impact of the EPSE™ Method on a plant’s carbon balance is always case-specific, but we have several examples where the net impact on carbon dioxide emissions has been extremely positive for a number of reasons: In one instance, the use of the EPSE™ Method significantly reduced the consumption of chemicals required to raise the pH, which is directly reflected in emissions from manufacturing and transport. As a result, significantly less sludge is also produced, which in turn leads to reductions in emissions from transport and disposal, the scale of which depends, for example, on the sludge disposal method. As the method is not temperature-dependent, no emissions are generated from water heating either. During testing and piloting phases, we always aim to establish a comprehensive picture of the potential for emissions reductions, as far as this is possible.
Does the process produce any gases?
The EPSE 1010 chemical does not normally cause gases to form. Any reaction gases are generally related to the composition of the water being treated and the pH adjustment. We always take the potential formation of gases into account as part of the plant design.
What permits does the EPSE™ Method require?
The EPSE™ Method is a chemical wastewater treatment process; as with traditional treatment methods, industrial operations are governed by environmental and other permits, which are determined by the authorities on a case-by-case basis for each plant.
Does EPSE have ISO 9001 and ISO 14001 certification?
In many areas, we follow the procedures set out in the standards, but we have not yet initiated any standardisation processes.
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EPSE company, references and responses to Customer questions
What happens after 1st contact?
The process usually begins with a brief technical discussion to review water quality, environmental requirements, and the client’s objectives. Following this, a preliminary desk analysis can be conducted, and laboratory or pilot testing can be planned. The goal is to quickly obtain reliable information about the specific benefits the EPSE™ Method can deliver at that particular site.
Where is the EPSE office located?
EPSE Oy’s office is located in Ylöjärvi, Finland, at Elopellontie 1 G. For further information, see the Contact Us page. EPSE Technology Inc.’s office, meanwhile, is located in Nevada, USA.
What should I do if I encounter problems with my EPSE process?
Please contact your point of contact immediately; they will direct you to the appropriate specialist. If you do not know who your point of contact is, you can use the email address technical@epse.fi. We offer immediate technical support in situations where there are disruptions to the EPSE process or where the metal concentrations in the treated water exceed the limit values.
How can I send samples?
We provide comprehensive instructions on how to submit samples in a separate document. You may also, as previously agreed, bring the samples to our premises at Elopellontie 1 G, 33470 Ylöjärvi. Our laboratory manager will provide further instructions if necessary.
How quickly are the analyses/tests completed?
Once we have received the samples, we aim to set a target timeframe for the completion of the analyses and tests, and we will notify you of this on a case-by-case basis. Laboratory tests typically take between one and four weeks to complete, depending on the number of tests and the number of analytes requested.
Who should I contact in different situations?
You can find our staff’s email addresses on our Contact Us page, and you can contact your designated contact person directly. We also have several mailing lists through which messages are forwarded to the relevant people:
- Chemical orders and related enquiries: tilaukset(a)epse.fi
- Support requests and technical enquiries: technical(a)epse.fi
- Laboratory enquiries:
laboratorio(a)epse.fi - General and administrative matters: info(a)epse.fi.
What information do you usually need about our operations?
We generally require basic information about the process, such as the volume, previous analysis results, the PI chart, processing targets, and the chemicals currently in use and their dosages. However, we always discuss the details on a case-by-case basis.
How big is the EPSE Team?
You can see all our team members on the contact page.
In which countries does EPSE operate?
EPSE’s office and laboratory are located in Ylöjärvi, Finland, but our operations also extend to the rest of Europe. EPSE Technology Inc. operates in North America, and through our partners we also have operations in Africa, Central Asia and China.
What makes EPSE a different kind of partner?
EPSE does not simply sell the customer a ready-made product; instead, we start by addressing the customer’s actual problem. Before selecting a solution, we assess the process, test the water or material under laboratory conditions, and draw up a proposal based on actual results. This ensures that the customer’s risk is kept to a minimum.
Can we come and visit?
We’d be delighted to tell anyone interested about what we do. Find out more in our visitor guidelines.
What is EPSE Technology Inc.?
You can find out more about EPSE Technology Inc. directly on our website.
Where, by whom and when was the EPSE™ Method invented?
The EPSE™ method was invented by Vesa Rissanen. You can find the story of EPSE on our website.
Which country does this technology come from?
The EPSE™ Method is 100 per cent Finnish technology.
Where are EPSE’s patents?
EPSE technology is protected by an international patent portfolio covering a total of 43 countries.
Where is the EPSE™ Method used, and what kind of references does EPSE have?
EPSE technology has been used in industrial applications in Finland and internationally. Some of the case studies are public, whilst others are subject to non-disclosure agreements. You can find the case studies produced in collaboration with our clients here.
What sort of partners does EPSE have?
EPSE has a wide range of partners in the fields of water treatment, plant design and construction, as well as in networks within the mining and other industrial sectors. We always strive to find local partners for our projects who share our values and operate in a responsible and high-quality manner. For example, in Kazakhstan, Central Asia, we work with the local Samruk-Kazyna Ondeau, in Uzbekistan with East Technic and Mesmer, and in South Africa and Zambia with Prosep Chemicals and their leading experts.
In Finland, our network of partners includes, amongst others, EastCham Finland Oy, Mining Finland and Business Tampere, through which we also receive valuable support in international markets.
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