Treatment and recovery of hydrocarbon solvents in pharmaceutical industrial wastewater

MPPE (Macro Porous Polymer Extraction) is Veolia's technology for removing hydrocarbons from pharmaceutical industry wastewater using macro porous polymer extraction.

For HSE Managers, wastewater treatment plants (WWTP) in pharmaceutical industries are increasingly viewed as a valuable source of utilities and by-products - not merely end-of-pipe facilities for treating production waste to meet discharge compliance requirements.

Understanding the complexity of pharmaceutical wastewater

Pharmaceutical wastewater is highly complex and can differ significantly between production processes—both in the amount and frequency (it may be generated continuously or in batches), as well as in its characteristics (it may be more or less biodegradable).

To better understand these variables, it is common to conduct a targeted audit of the wastewater treatment plant (WWTP). This involves dividing the plant into sections to locate possible sources of toxicity and pinpoint areas needing improvement. In addition, laboratory tests are carried out on composite samples or in small-scale pilot plants to ensure the selected treatment process is both optimized and effective.

Balancing compliance, recovery and efficiency

For example, when it comes to the toxicity of wastewater caused by specific compounds, API residues, or solvents used in production and synthesis, plant managers are constantly searching for technologies that can improve existing treatment systems. Their aims are to prevent regulatory exceedances and to enable water recovery, which helps reduce the use of additional well water or municipal supply. Space in these facilities is often limited, and keeping energy consumption as low as possible is a key priority.

The presence of hydrocarbons in pharmaceutical production varies depending on the process, but they are used most extensively in R&D labs, biotech, and API manufacturing through chemical synthesis. The industry regularly relies on more than 30 different solvents, including chlorinated solvents, dichloromethane (for vitamin and antibiotic extraction), ethanol, methanol, polar solvents like acetone, GMP-grade IPA used for oral solids or disinfectants and skin creams, and aromatic hydrocarbons such as BTEX and toluene.

MPPE™ technology has proven to achieve up to 99.9% removal of these substances at various facilities. Because discharge limits for these compounds are strict and are expected to become even stricter, hydrocarbons remain a key focus for both regulatory compliance and corporate sustainability initiatives.

Distillation columns are often used to treat hydrocarbon-laden wastewater. However, these systems have high operating costs due to significant energy use, and their performance is frequently disrupted by the need for periodic cleaning. This creates a demand for more efficient and sustainable treatment alternatives.

MPPE™ and the extraction process

Veolia's Macro Porous Polymer Extraction (MPPE) technology is a high-efficiency solution for removing dissolved and dispersed hydrocarbons from wastewater. It is an automatic process, with minimal operational resource requirements, without the use of chemicals, and it produces neither sludge nor waste gases. It consists of a liquid with strong affinity for hydrocarbons, fixed within a bed of porous polymer beads. When wastewater passes through this bed, hydrocarbons migrate from the aqueous phase to the extraction liquid. The purified water can then be further treated, reused or discharged.

When the extraction liquid is saturated with hydrocarbons, it is periodically regenerated by heating it with low-pressure steam at 112°C. The hydrocarbons contained in the extraction liquid are then condensed and removed in liquid phase in a separator. Almost 100% of the hydrocarbons are removed. The plant consists of two MPPE™ process columns, to ensure parallel and continuous operation between extraction and regeneration. The wastewater flow is conveyed to the second extraction bed during regeneration of the first column, and vice versa, thus ensuring continuity of the treatment process.

In MPPE™ extraction technology, removal efficiency can also be controlled by varying the amount of filter media in the columns.

For polar compounds, such as Acetone, IPA, MEK, MTBE, THF, Phenols, a more specific type of filter media is used, while maintaining the same operating principle, thus also allowing the removal of a wider range of hydrocarbons.

Key factors for MPPE™ applications

The success factor of MPPE™ technology is the removal of the most complex substances from industrial wastewater. We refer to the most toxic substances that are not absorbed in conventional biological treatment sections. The removal of these substances enables downstream biological treatment, or further treatment sections for water reuse within the site. Furthermore, removing and concentrating the most toxic substances, even with a factor of 200, significantly reduces disposal and the cost of external third-party treatments.

Regarding energy consumption, an MPPE™ plant consumes 10-20% of the same energy required in a conventional distillation system. But let's look at the additional advantages below.

Although MPPE™ technology is generally used to remove traces of hydrocarbon solvents, with its high recovery efficiency it can be suitable for extracting other high-value compounds from wastewater, which with subsequent treatments can be reused in the pharmaceutical process. There have been cases where recovered solvents have been reused as is, extracted directly from the MPPE™ plant.

But there are also other aspects to consider. Distillation columns can suffer from fouling and, when this occurs, the column must be cleaned using solvents. In this situation the distillation column remains out of service, losing process efficiency, which does not happen with an MPPE™ plant.

A Scandinavian success story: From distillation to MPPE™

For further information, upon request we can present a plant case in the Scandinavian region, where the pharmaceutical industry was using a conventional distillation column in its WWTP. Wastewater treatment was often interrupted due to fouling that occurred in the distillation towers. Energy consumption was also very high and the company was looking for improvement alternatives.

During the plant expansion phase, Veolia's MPPE™ technology was considered. Through pilot laboratory tests, which the customer attended, Veolia was able to demonstrate that MPPE™ technology allowed for process improvements and greater energy efficiency. The plant was therefore built with a modular container solution, allowing for reduced space requirements near their tank farm.

Hydrocarbon recovery

MPPE™ is not only a solution that reduces energy consumption for treating hydrocarbon residues in pharmaceutical industry wastewater. Efficiency goes hand in hand with the removal of almost 100% of hydrocarbon solvents used in the pharmaceutical sector. Water treated with MPPE™ can therefore be further purified with other downstream sections, for which a low hydrocarbon value is typically required.

In this way, pharmaceutical companies are helped to achieve significant water savings in their processes, and the recovery of material resources such as solvents and even specific high-value products within the wastewater stream is also supported. Often, by effectively treating even just one pollutant element in the wastewater stream, MPPE™ can solve a significant part of wastewater problems from the pharmaceutical sector.

Ultimately, the MPPE™ process enables pharmaceutical companies to ensure their business continuity by guaranteeing that processes and projects remain within environmental regulatory limits both now and in the future.

Would you like to know more about our pharmaceutical wastewater treatment solutions?