ToxSorb Case Studies
Decades of military industrial production has lead to the widespread contamination of Israel’s coastal aquifer, with a wide array of pollutants such as perchlorate, nitrate and other explosive compounds. In 2006, extensive groundwater testing throughout Israel lead to the closure of more than 10 wells, previously used for drinking purposes.
Kfar Yarok, an impacted village nearby Tel Aviv, relied heavily on their groundwater for irrigation and potable drinking water. The Israeli authorities closed the well due to perchlorate, ethylene dibromide (EDB) and nitrate groundwater contamination in the surrounding aquifer.
Based on a successful field pilot conducted by ToxSorb under the supervision of the Israeli Health and Water Authority, Hakfar Hayarok selected ToxSorb to build own and operate (BOO) a full-scale drinking water treatment facility (100,000m3/yr) using its patented Modified Activated Carbon (MAC) technology. As a result of this successful technology demonstration, the Israeli Water Authority granted Hakfar Hayarok an exemption from the water production fee (i.e. pumping fee) for a period of 10 years, based on local treatment with ToxSorb. Since ToxSorb’s cost of treatment is a much lower than the costs of alternative drinking water supply, this translates into significant cost savings for the community.
ToxSorb designed a treatment facility, engineered to selectively remove both perchlorate and EDB using its proprietary MAC media. Once treated, a partial stream from the effluent of the MAC filters is routed through a reverse osmosis system to achieve the blended target for nitrate removal. ToxSorb’s facility at HaKfar HaYarok is scheduled for commissioning in September 2017.
ToxSorb’s MAC for perchlorate exhibits four significant advantages over the competition:
1. Selectivity: MAC exhibits the highest selectivity in the industry, removing perchlorate in the presence of high concentrations of competitive ions (i.e. chloride, bicarbonate, sulfate, etc.).
2. Dual-Purpose Filtration: MAC has the unique ability to remove organics and inorganics on the same platform, facilitating the adsorption of EDB and perchlorate in a single process.
3. Media Regeneration: MAC can be regenerated using standard industrial chemistry, enabling the reuse of the media without affecting performance. This allows MAC to outperform traditional ion exchange resins, which require frequent disposal and replacement.
4. Perchlorate Reduction & Brine Elimination: MAC’s unique chemical property facilitates the reduction of perchlorate to a non-toxic brine, eliminating the need for hazardous waste disposal.
Metal Surfaces Inc
In late 2015, ToxSorb signed a deal with Metal Surfaces Inc, one of the largest precision plating shops in North America, specializing in the Aviation, Aerospace, Electronic, Interconnect and Automotive fields. MSI’s operations include in a wide range of water intensive reel-to-reel plating and other metal finishing processes, including cyanide, silver, gold, cadmium, chromium, nickel, electroless nickel, zinc, tin and more.
In the past, MSI relied heavily on conventional wastewater treatment for regulatory compliance and environmental safety. Problematic wastewater streams including hexavalent chromium and cyanide-complexed metals were segregated and treated using standard industrial chemicals such as sodium bisulfite and sodium hypochlorite. The resulting trivalent chromium and cyanide-free wastewater was then combined with MSI general wastewater stream, before undergoing pH adjustment, settling, neutralization and discharge to the local sewer. While MSI’s system complied with wastewater discharge permits, it was inefficient in chemical consumption and generated high salinity wastewater that was impossible to reuse. With California entering its fifth year of the drought, MSI was actively looking for new technologies to recycle water and improve the operational
efficiency of its WWTP. ToxSorb’s experience in Zero-Liquid-Discharge, combined with its unique adsorption / reduction filtration technology was a perfect fit.
ToxSorb worked with MSI to design a custom filtration system capable of treating a mixed wastewater stream, including all of the hexavalent chromium and cyanide-complexed rinses from the factory.
This included a steady flow of wastewater ranging from 15,000 – 20,000 GPD, in addition to periodic spikes in concentration from weekly bleeding of chromium and cyanide drag-out solutions. The proposed treatment system incorporated ToxSorb’s proprietary Modified Activated Carbon (MAC) media, capable of reducing hexavalent chromium and oxidizing cyanide inside the filter, without the use of chemicals. The effluent from ToxSorb’s system would need to exceed the highest standards in the metal finishing industry, required for military applications (<50 uS/cm). The final treated product would need to be chromium and cyanide-free, so that it could be reused anywhere throughout the factory.
The only waste produced from the system would come from the periodic regeneration of the filters, which would produce an estimated 1,500 – 2,500 gal of non-toxic, brine each week, <3% of the treated flow. Since this solution contained high-concentrations of valuable metals, ToxSorb and MSI decided to incorporate an on-site precipitation and settling process to capture these residuals separately from the rest of the WWTP. Once separated, the resulting supernatant would be blended back into MSI’s general wastewater stream, pre-neutralization.
- Central Treatment System: The main treatment system incorporating a series of 5 columns containing 140 ft3 of mixed-bed ion exchange resins and MAC media, designed for chromium reduction, cyanide destruction and de-ionization <50 uS/cm.
- Polish Treatment System: A single MAC column designed to remove any remaining hexavalent chromium and cyanide in the regeneration solution, before discharging to MSI’s general WWTP.
- Water Savings: 20,000 gallons / day saved in fresh water purchase and wastewater discharge
- Chemical Reduction: Elimination of NaHSO3 and NaClO and a reduction in NaOH downstream in the general WWTP.
- Sludge Reduction: Less sludge production, through the reduction of chemicals and the partial elimination of city water
- Improved Water Quality: Higher quality rinsing water (<50uS/cm)
- Water Independence: Lower impact from supply and demand of water
Today, ToxSorb’s chromium and cyanide reuse system at MSI is fully operational, exceeding its design target for water quality. ToxSorb and MSI are currently evaluating other streams for reuse, including their nickel and general acidic / alkaline rinses.
In August 2015, ToxSorb was selected to design, construct and operate a state-of-the-art wastewater treatment plant by PCB Technologies, a leading manufacturer of printed circle boards in Israel.
PCB was looking for a robust filtration technology capable of reusing the majority of their wastewater back to the manufacturing process, while concentrating salinity for cost-effective discharge to the sea. ToxSorb’s combination of technology and deep process expertise in industrial wastewater, made them an ideal candidate for this undertaking.
ToxSorb’s treatment system was designed with two primary goals in mind:
The first was to increase the volume of recycled wastewater from ~50% to >95%, while maintaining the highest standards for industrial wastewater reuse (up to a level of <0.1 μS/cm).
The second goal was to disconnect the factory from the regional wastewater facility, reducing treatment cost and eliminating the potential for environmental penalties. Achieving this goal would significantly reduce the largest operational cost driver for the client.
Following a mapping process of over than 100 water sources, ToxSorb designed and constructed a full scale WWTP based on its specialized media and other complimentary technologies, to treat the factory’s entire wastewater stream (700m3/day). ToxSorb’s process design enabled the client to achieve the maximum recovery rate (>95%), by segregating the highest salinity wastewater streams from the factory and combining them with the regeneration brine from ToxSorb’s MAC filters. The treated non-toxic effluent could then be cost effectively evacuated under permit to the Mediterranean Sea. This amounted to a very small volume of wastewater <25m3/day, while the vast majority is treated and reused back to the process. In order to answer the local Water Authority requirements during the full-scale system construction period, ToxSorb designed and constructed a temporary treatment system. Brine evacuations from this system started in July 2016, and enabled the factory to maintain compliance with sodium and chloride effluent standards. Elements of the temporary system would be integrated into the full-scale system, reducing overall construction costs.
ToxSorb's WWTP is engineered to provide PCB with the following benefits:
- Eliminating wastewater compliance issues: ToxSorb’s WWTP does not discharge wastewater to the sewage system
- Water Savings: ToxSorb delivers substantial savings in water and sewage, through an efficient application of industrial wastewater reuse.
- ToxSorb produces high quality water (as low as <0.1 uS/cm), critical to the production of printed circle boards.
All of the above translates into valuable time and money savings in operations to our client.
In 2006, field tests conducted by the Israeli Ministry of Health (MOH) revealed abnormal values of Perchlorate and Ethylene Dibromide (EDB) in Green Village's primary groundwater source well, which quickly lead to the closing of the well. Using ToxSorb’s MAC technology to remove Perchlorate and Ethylene Dibromide from the well has allowed the village to reclaim this valuable drinking water source.
In August 2013 ToxSorb received approval from the Israel MOH to build and operate a full-scale drinking water treatment facility at Green Village. This approval was given following the positive results of ToxSorb’s pilot in Green Village in July 2011, which effectively removed both Perchlorate and EDB in concentrations 4 x higher than original system design. This system was fully implemented in Q1 2016.
This project at Green Village will represent the first treatment facility of its kind in Israel, truly a pioneering achievement. Restoration of contaminated wells provides an important contribution to the functioning water balance in Israel, and especially to the nearby population benefitting from clean water. ToxSorb's full-scale drinking water treatment facility is expected to purify 25,000,000 gal/year.
ToxSorb’s pilot at Green Village demonstrated a consistent ability to remove perchlorate and EDB at concentrations 4 x higher than initially observed and designed for (~40ppb). ToxSorb's full-scale drinking water treatment facility is expected to purify 25,000,000 gal/year.
FULL SCALE PLANNING
ToxSorb's full-scale treatment facility will be designed for the removal of perchlorate in concentrations <200 ppb and EDB in concentrations <0.3 ppb during normal operations. However, given the fact that contaminantconcentrations around Green Village have been increasing steadily over the last decade, ToxSorb has designed its system with the capacity to handle an additional 50% increase in concentration. In the event of increased pollutant concentrations, ToxSorb’s system can be adjusted to increase the frequency of regeneration, enabling the additional uptake of pollutants at the designed flow rate. While this intensified operational regime will consume more chemicals, it will not have an effect on the waste generation of the system, since the brine produced will still be rendered non-toxic through the ability of NP2TM to reduce ClO4- into non-toxic Cl - and O. This process advantage allows the brine stream to be recycled back to the head of the plant, eliminating the need for costly disposal. In 2015, in preparation for the design of the full- scale system, ToxSorb ran an additional pilot with the objective of identifying the breakthrough curve of the NP2TM media. The results from ToxSorb’s internal analysis show the media’s ability to deliver consistent results below the Limit of Detection (4ppb), up to 5,000 Bed Volumes (BV). ToxSorb Continues to experiment with lower retention times in an effort to reduce the overall size and cost of the Full-scale system.
In 2013, ToxSorb began working on its most ambitious project to date, a high volume chromium removal and reuse project at an Italian Galvanic factory named Dalla Torre, specializing in decorative chrome and nickel-plating of furniture.
In the past, Dalla Torre relied on traditional means of chemical / physical treatment, reducing hexavalent chromium using sodium metabilsulfite, before precipitating the trivalent chromium with caustic soda and discharging the treated wastewater to the sewar system. While this system complied with local Italian regulations, it was inefficient in its use of water, electricity and chemicals and produced high quantities of sludge. Dalla Torre was looking for a solution that would maximize the reuse of water back to the process, while generating significant cost savings in the process. ToxSorb’s unique technology for chromium removal and reuse answered all of the client’s requirements.
ToxSorb’s system was engineered to operate in extreme loading conditions, indicative of normal operations at a high volume decorative chrome factory like Dalla Torre. The objective in this case, was to remove heavy spikes of chromium in the rinse water after the electro-plating process, to prevent a build up of concentration in the water over time, through subsequent rinsing events. For this solution, ToxSorb engineered a chromium treatment system for all three of Dalla Torre's chromium plating lines, incorporating the use of ToxSorb’s process knowhow and proprietary modified activated carbon “MAC” technology for chromium removal. ToxSorb’s system design incorporated two basic treatment components:
- Central Treatment System: A large centralized system designed to treat the upstream chromium rinsing basins in each line to the effluent requirements for discharge <1 ppm chromium.
- Kidney Treatment System(s): Three smaller kidney system installed on the final chromium rinsing basin in each line, designed to re-circulate and maintain a low electro-conductivity value in each basin <150 us/CM
ToxSorb’s unique chromium treatment and reuse system provided Dalla Torre with a number of key benfits including:
- Water Savings: Reduction in overall water consumption from 30 m3/day to 11 m3/day, through smart water reuse.
- Chemicals Reduction: Elimination of sodium bilsulfite and a sharp reduction in caustic soda used for precipitation
- Sludge Reduction: Significant reduction in sludge production, through a decrease in chemicals and water flow
- Water Quality: High quality water (EC <150 μS/cm) in the final washing basin, improving the quality of the plating process
- Regulation Compliance: Compliance with the Italian wastewater regulations
ToxSorb’s treatment system was successfully installed in Dalla Torre in 2014. As a result, Dalla Torre has reduced its overall water consumption by a factor of 7, while at the same time improving the quality of water being delivered back to the rinsing process. In addition, the client has benefited from a steep reduction in chemicals and sludge production, due to the ToxSorb technology’s ability to reduce the hexavalent chromium to trivalent chromium without adding salinity (i.e. chemicals) to the water supply. Lastly, the reduced volume of water still being discharged from the factory conforms with the Italian regulation for chromium, pH and EC.
Based on the good results generated by the ToxSorb chromium treatment system, Dalla Torre and ToxSorb are discussing the application for other ToxSorb technologies for Nickel and Copper removal in the factory. These projects are scheduled for 2015 & 2016 respectively.
In 2013, ToxSorb began working with AG Technical, an Italian galvanic factory specializing in silver-plated copper fasteners and other materials for high voltage systems. The objective of this project was to engineer a zero-liquid-discharge (ZLD) system capable of maintaining high quality water in the washing basins post-galvanization. At the same time, AG Technical
demanded a solution that would significantly reduce their operating costs, when compared to their existing ZLD resin system, which they were regenerating on a daily basis.
Since AG Technical was producing first-class quality products, they required extremely low electro-conductivity (<50 μS) in their washing basins, to maintain an optimal surface finish. In order to keep up with production, ToxSorb’s system was engineered to remove heavy spikes of silver rapidly, in order to clean the basin before the next rinse.
ToxSorb is designing a full-scale ZLD system using its proprietary Modified Activated Carbon (MAC) media, engineered to treat all of the silver cyanide washing water in AG Technician's factory (9 m3/hr),
This system will operate as a massive kidney system,
recircula-ng and cleaning the washing water from each of AG Technical’s three galvanic lines, post-
silver coa-ng and passiva-on. An automated regen-
era-on system will be integrated into the MAC unit, allowing the en-re process to be controlled on site or remotely from Israel.
ToxSorb's unique silver removal system will provide AG Technical with the following benefits:
- No Authority Regulaons: ToxSorb’s Zero Liquid Discharge system does not discharge into the sewage system, removing the need for end-of- pipe monitoring and analysis
- High Water Quality: ToxSorb’s system will significantly improve the average water quality in the rinsing basins <50 μS, ensuring an optimal finished product
- Operational Cost Savings: The high performance of ToxSorb’s MAC enables less frequent regeneration of the media, saving AG Technical valuable time and money in the process
In addition to the treatment of its washing water, AG Technical has requested ToxSorb to develop an improved process to recover the silver from the static washing system. If successful, this process will produce an additional revenue stream for the client, offsetting the cost of treatment.
AG Technical will also be assisting ToxSorb with operational and maintenance services to other third party clients in Italy.
Weapon Coating Factory
In 2010, ToxSorb was engaged to install a chromium filtration systems at a local weapon coating factory in Israel. The purpose of this system was to remove the chromium from the rinsing basins, which are used to wash the metal products after the chromium electro-plating process. Treating the chromium would allow the factory to recycle the water in the rinsing basins instead of dumping and refilling them a few times a day, saving the client valuable time and money in operation.
Since the factory was working with highly concentrated chromium solutions, ToxSorb’s systems needed to be able to remove heavy spikes of chromium quickly, in order to clean the rinsing basins before the next rinse.
To treat the rinsing water, ToxSorb designed filter systems using its proprietary Modified Activated Carbon (MAC) media, which were installed as a kidney attached to the main rinsing tank (1-3 m3/ each). ToxSorb’s system have two major components:
- The MAC filter unit, which was installed on-site at the factory
- The regeneration unit, which is located off-site at ToxSorb’s service center
The MAC filter includes a 100L cylindrical filled with 50 kg of MAC-Cr adsorptive media. Water is circulated from the rinsing tank through the MAC filter, and the discharge is set to 800 L/h, thus the total tank volume was designed to pass through the unit every 1.25-3.75 hours. The regeneration process was designed separately from the MAC unit in this project, to save the client the inconvenience and regulatory approval of handling the concentrated chromium brine. In future designs, the regeneration component will be integrated into the MAC unit, allowing the entire process to be controlled on site or remotely from Israel.
ToxSorb’s MAC filtration system has been operating successfully for the last 3 years, reducing the chromium concentration in the factory’s rinsing basins to non-detect levels (<25 ppb). Weekly samples were taken from the rinsing basin and the MAC system outlet, to ensure that the chromium concentration, pH, and EC are all within acceptable parameters.
Each MAC system operates for approximately 6 months before requiring regeneration, translating to extremely low operational costs for the client. In 2011, the system was expanded to treat the alkaline cleaners in the factory.