Emulsions are finely dispersed mixtures of normally immiscible liquids. They end up on consumers’ tables as homogenized milk in the food sector, for example. They primarily consist of water, fat and protein. According to their nature, the fat droplets contained in raw milk are not very homogeneous. For process engineering reasons, it is therefore important to reduce their size in advance and achieve an even distribution. This is the only way that the end product can meet both the quality requirements of the manufacturer and consumer expectations. However, as there are increasingly demanding emulsions in other areas besides the familiar milk, such as baby food, pharmaceuticals, cosmetics or fine chemicals as end products or even just intermediate products, which require the highest purity in particular, LEWA has developed the LEWA homogenizer test system. The system can be used to test the aseptic functioning of a homogenizer based on a hygienic hermetic process diaphragm pump. Thanks to a homogenizing valve that is also hygienic, it can be flexibly adjusted to the requirements of different emulsions. The compact system can be integrated into both the circuit (“stand-alone”) and the process line, enabling it to be continuously operated aseptically. The fluid is supplied via an integrated heatable vessel or a separate media connection.

Not too creamy, not too runny: everyone knows how challenging emulsions are: be it mixing a salad dressing or preparing a stable Béarnaise sauce in your own kitchen. The requirements of industry go far beyond those of kitchen preparation. “In addition to knowledge of dispersion technology, there is an increasing focus on hygiene requirements and uninterrupted robustness in industrial production. And this is where the advantages of hermetic homogenization or spray tower pumps come into play: for example, to maintain a stable and pure product quality after heat treatment,” said Dr.-Ing. Hans-Joachim Johl, Lead Product Manager Life Sciences/Clean Processes at LEWA GmbH. Put simply, the piston diaphragm pump is the heart of the system for conveying fluids under high pressure through a narrow opening. Due to the high shear and the resulting collision of the droplets, they are crushed and evenly distributed. Alongside a high-pressure pump used as a pressure generator, the systems used in this field consist of a hydraulic consumer, which is called the “homogenization valve.” This often has a two-stage structure to counter the re-agglomeration of fat droplets, for example.

The pump experts from Leonberg, Germany, have developed a new rental and test system to meet the stringent requirements of an efficient dispersion process from both the hygiene and process engineering perspectives. It is based on proven triplex pump technology and, thanks to its compact design and flexible control system, can be easily integrated into pilot or even production environments. In particular, products with unusual requirements such as fluids with high undissolved abrasive components (e.g. calcium carbonate, tricalcium phosphate) can be tested with the system from LEWA. Even small quantities of expensive fluids can be tested in “stand-alone” operation without any problem.

Optimal results from the interplay between pump and valve
The heart of the system is the proven LEWA triplex high-pressure process diaphragm pump. It ensures that the process fluid flows through the integrated two-stage homogenization valve at the required flow rate and pressure. It is dynamically controlled and is designed for a maximum pressure of 400 bar and a flow rate of up to 150 l/h in the test system. The LEWA triplex piston diaphragm pump also offers a decisive advantage for homogenization: Due to its design, the diaphragm pump does not require dynamic sealing systems. The PTFE sandwich diaphragm – additionally equipped with leakage detectors – ensures a hermetically sealed working chamber, such that no emission or leakage of substrate or cleaning media or contamination of the fluid can occur. In addition to this function, which enables aseptic process control, all media-relevant components are designed in accordance with the applicable hygiene specifications, e.g., the “Hygienic design of pumps, homogenizers and steaming equipment” EHEDG guidelines, and are easy to clean inline (CIP, SIP) – but also easily accessible for inspection and maintenance purposes.

“The actual homogenization process benefits from the close interplay between customer-specific conveyor units and system components,” explained Dr. Johl. First, a hygienic twin screw pump generates a specified inlet or suction pressure on the suction side of the high-pressure pump, which is particularly important for higher viscosities. Next, the speed-controlled high-pressure diaphragm pump conveys the fluid at the required flow rate to a preselected pressure P2 in the second stage. The valve remains pneumatically closed according to the selected pressure. As soon as the pressure and pump capacity are reached, the homogenization valve of the first stage closes to the extent that the specified value also applies there. The valve of the second stage is now no longer controlled. “The ratio between the pressures is usually P2 < 1/5 x P1, but it can also be freely selected. The homogenization pressure of the first stage, which is now leading, is maintained by pneumatic valve control of the dispersion gap. In this way, the homogenization process remains virtually free from pressure fluctuations. The choice of type and design of the homogenization valves can be specified by the customer for later scaling of production systems. Due to sufficiently selectable pressure reserves, a later system can also directly supply a downstream spray drying step, which further increases the efficiency and flexibility of the process.

Compact design and flexible control for versatile use
All components are designed for hygiene and are mounted on a common base frame with a “wash-down housing” for the pump drive. This compact design enables the system to be installed such that it saves space in the production environment. Depending on whether it is operated in a circuit or continuously, the fluid is supplied via either the integrated heatable double-walled tank with a capacity of 60 l or a separate media connection. In addition, the LEWA smart control control system is integrated into a control cabinet mounted on the metering frame: also in hygienic design. Various modes and preconfigured operating sequences (cleaning, homogenizing, etc.) are pre-installed for simple and flexible operation. “The safety of the system is rounded off by various protective measures: a safety valve that can be automatically vented for cleaning to protect the system against overpressure on the low-pressure side, a pump-integrated pressure relief valve on the high-pressure side and various pressure and temperature transmitters for process monitoring, as well as visual and acoustic warning elements,” added Dr. Johl.

From March 19 – 22, 2024, visitors to Anuga FoodTec in Cologne will have the opportunity to experience the LEWA homogenizer test system in action. Dr. Hans-Joachim Johl and other LEWA experts look forward to answering questions and having interesting discussions.

]]> https://pumpindustry.com/aseptic-process-diaphragm-pump-for-field-trials-on-homogenization-of-demanding-emulsions-march-4-2024/feed/ 0 https://pumpindustry.com/removing-pharmaceuticals-from-water-supplies-is-a-major-challenge-for-the-wastewater-treatment-industry-january-25-2024/ https://pumpindustry.com/removing-pharmaceuticals-from-water-supplies-is-a-major-challenge-for-the-wastewater-treatment-industry-january-25-2024/#respond Thu, 25 Jan 2024 10:39:46 +0000 http://pumpindustry.com/removing-pharmaceuticals-from-water-supplies-is-a-major-challenge-for-the-wastewater-treatment-industry/ The current EU Urban Wastewater Treatment Directive is more than 30 years old, and it has made dramatic improvements to the water quality in European rivers, lakes and seas. However, several pollution challenges remain and are not covered by the current legislation.

One of the most prominent is pharmaceutical residues, which are having a detrimental effect on wildlife and human health, leading to a revision of EU Directive 91/271/EEC.

Mattias Feldthusen, Director Process & Product Development for Nordic Water, a Sulzer brand, looks at the latest proposals from the European Union (EU) and how they will affect operators of wastewater treatment plants.

European countries have set up collecting systems and wastewater treatment plants with the help of EU funding. There is a high level of compliance with 91/271/EEC across the EU, with 98% of wastewater collected and 92% satisfactorily treated, according to the current coverage of the Directive.

Paying for polluting

The latest proposals will require producers of pharmaceuticals and cosmetics to pay for the cost of removing micropollutants that come from their products and end up in wastewater, thus implementing the “polluter pays” principle.

Currently the pharmaceuticals and the cosmetics sectors are jointly responsible for 92% of the toxic load in wastewater. For both sectors, there is sufficient evidence regarding the existence of micropollutants from these products in wastewater and there are treatments available to remove their harmful residues.

The EU Commission raised a new proposal for the Directive in October 2022. It aims, among other things, to further reduce pollution, energy use and greenhouse gas emissions, to make industry pay for the treatment of micropollutants and ensure EU countries monitor pathogens in wastewater. This last proposal was borne from the Covid-19 pandemic, which showed that viruses can be tracked with high reliability in wastewater.

Harmful effects

Many pharmaceuticals can remain in wastewater throughout the treatment and discharge processes and have been detected in rivers, streams and lakes around the world. Once in the environment, these chemicals can detrimentally affect aquatic wildlife. Natural and synthetic estrogen compounds are known to cause decreased fertility and other negative reproductive effects in fish. The inhibition of growth and development of secondary sexual characteristics was reported in some species after exposure to a variety of endocrine-active chemicals.

Other commonly used compounds that are persistent in wastewater treatment effluent are nonsteroidal anti-inflammatory drugs. These compounds, including ibuprofen and naproxen, have been discovered in the environment at concentrations of 300 ng/L in surface waters , and they elicit negative reproductive effects on aquatic organisms at low, but potentially environmentally relevant, concentrations.

Furthermore, commonly used antidepressant drugs can elicit behavioral changes in fish. Antibiotics in the environment lead to the development and propagation of antibiotic resistance. Concentrations exceeding 100 ng/L have been reported to influence the proliferation of antibiotic-resistant bacteria and thus present potential public health concerns.

Introducing the solutions

For antimicrobial active pharmaceutical ingredients (APIs), there is also concern that environmental exposures could select for antimicrobial resistance (AMR) in microorganisms and thus contribute to the global AMR crisis. It is therefore crucial that a much greater emphasis is put on removing these residues, which are not covered by the current legislation; naturally this will require additional treatment processes to be installed.

Filtration technology that has been developed in recent years has the capabilities to remove pharmaceutical residues, however there is no single solution for every treatment plant. There a several factors that need to be considered to ensure an optimized filtration process is achieved.

Granular activated carbon filters are among some of the best options, especially for treatment plants that employ sludge digesters, where they are the simplest and most cost-effective solution, even with short retention times. At the other end of the scale, reverse osmosis (RO) and nano filtration (NF) are very effective. However, there are high operating costs to be considered, as well as more complicated cleaning processes.

Integrating filtration processes

Some treatment works, mainly in southern Europe, use incinerators to dispose of processed sludge and these can handle powdered activated carbon in the sludge. In northern Europe, most treatment works have a digestion process to produce biogas, which is used by an engine and generator to reduce the energy bill for the plant. In this case, powdered activated carbon (PAC) would reduce the efficiency of the process and eventually needs to be removed from the digester.

Many treatment plants will already use a sand filter as a tertiary process and these offer an opportunity to introduce granular activated carbon (GAC) filters. Nordic Water has been running large-scale trials of GAC filters that can be installed in the sand filter basins and operated continuously, without the need for backwashing. On other sites, GAC filters have been installed in several silos, which keep the footprint of the new process to a minimum.

Following a pilot in Germany, Nordic Water has been contracted to install a brand new GAC system that will involve the construction of concrete basins that will house 120 DynaSand carbon filters.

Customized solutions

Pilot plants and full-scale trials of these filtration processes have been going on for several years, enabling manufacturers such as Nordic Water, to gain more experience of how different treatment processes interact. In one trial, three different process streams were installed, a sand filter after ozonation, a GAC filter after ozonation, and a stream with only GAC. The trial results demonstrated the most effective process for this site and the plant has since made plans to redesign the final process area to achieve the best effluent standards.

In one case, a treatment plant had high chloride levels and they initially caused rapid corrosion of the stainless steel filter tanks, whereas the adjacent sand filters suffered no such problems. The combination of carbon and high chloride levels created an environment conducive to corrosion.

For this site, the materials were reassessed and a fiber reinforced plastic (FRP) was used instead. The plant, which is in Sweden, uses a three-stage process of a DynaSand filter, ozonation treatment and a DynaSand carbon filter.

This solution continues to give excellent results for the final effluent. In fact, all effluent samples taken during the initial two-month sampling period showed concentrations below the detection limit and could not be quantified. That included all 24 analyzed pharmaceuticals, meaning the filters deliver almost complete removal of the substances.

Working for a better future

As the new EU legislation is revised to tackle the challenges of micro-pollutants and pharmaceuticals, pressure will increase on wastewater treatment plants to adopt new filtration technologies. Achieving the most effective solution will depend on many factors and it is important that each site understands its own unique set of circumstances.

Under Article 8, by December 31, 2030, Member States will have to ensure that 50% of discharges from urban wastewater treatment plants treating a load of 100’000 population equivalent (p.e.) and above are subject to a 4th stage of treatment. This will cover all treatment plants by the end of 2035.

To fulfil these requirements, national water municipalities need to start planning their strategy as soon as possible. Working with experts in this field who can identify the most effective solution that fits within the available footprint, ensures operators will achieve the proposed standards. In this way, Europe will make a very significant contribution to reducing pharmaceuticals and other micro-pollutants in its water supplies.

]]> https://pumpindustry.com/removing-pharmaceuticals-from-water-supplies-is-a-major-challenge-for-the-wastewater-treatment-industry-january-25-2024/feed/ 0 https://pumpindustry.com/expansion-and-upgrade-verderflex-idura-family-31-august-2023/ https://pumpindustry.com/expansion-and-upgrade-verderflex-idura-family-31-august-2023/#respond Thu, 31 Aug 2023 03:42:58 +0000 http://pumpindustry.com/expansion-and-upgrade-verderflex-idura-family/ Verder Liquids is proud to announce an expansion and upgrade to the Verderflex iDura peristaltic pump range. The new additions to the family include the iDura 45, iDura 55, iDura 55HF, iDura 65 and the iDura 80. The Verder IoT application has also been introduced to enable online data monitoring across the entire iDura range, from 5 to 80.