Pharma Water System Design and Control to Reduce Microbiological Contamination

Maintaining high water quality is essential for manufacturers’ needs and industry standards. Water-borne microbes are pervasive and diverse in their capacity to endure and flourish in different environments.

As a result, a water system that is out of control has the potential to damage patients or tamper with pharmaceutical products.

In order to avoid interactions with other product constituents or medicinal compounds, water must be purified. Additionally, microbiologic monitoring and control of water are required.

Based on reliable technology, chemical and physical water purification processes may typically lower the level of impurities to less than one part per million (or 1:10-6). Assay sensitivity for these techniques is in the parts per billion range.

Since pre-treatment equipment and the reverse osmosis (RO) system are particularly susceptible to contamination, they need to be tested, cleaned, and maintained on a regular basis to avoid bacterial buildup.

Let’s study the microbiological issues in more detail.

In addition to being screened for germs including escherichia coli, enterococci, bacterium aeruginosa, and fecal coliforms, potable water from private water companies or municipalities is monitored to make sure that levels of chemical contaminants stay within specified safety guidelines.

If bacteria in the water are not eliminated, they start to assemble, stick to objects, and create biofilms.

Multispecies formations called Biofilms are wrapped in an extracellular polysaccharide matrix. They offer the bacteria physical defense and adhesion, and if left undisrupted, biofilms can discharge bacterial populations into the water, resulting in protracted microbial colonization.

The main problem is the development of biofilms, which are microbial communities that resemble slime when bacteria stick to a surface (such as pipework with a poor flow rate).

Bacterial cells secrete a polysaccharide called glycocalyx after becoming connected, which causes a biofilm to form (hydrated polymeric slimy matrices). Each bacterium may enclose itself on the surface thanks to the glycocalyx; as these organisms gather, biofilm develops.

The process of biofilm formation:

• The surface is populated by individual cells (initial attachment).
• Permanent attachment.
• Extrapolymeric materials are created, and the connection becomes permanent.
• Growing and maturing biofilm architecture.
• Over time, individual cells (or groups of cells) are liberated from the biofilm.

Pipes and tanks are more susceptible to developing contamination than any other aspect of the water system if they are badly designed or not maintained properly.

The general requirements for well-designed pipes are:

1. Internal surfaces that are smooth:

Rugged surfaces hold microorganisms better than smooth surfaces, so it’s crucial to resist corrosion and prevent rouging (the production of iron oxide) (as can be achieved by the electropolishing of stainless steel). Smoothness might also be disturbed by pipe junctions and welds.

2. Constant water flows in tanks and swift piping flow:

It has been determined that speeds in the region of 1-2 meters per second are sufficient. As a result, fewer opportunities exist for microbes to stick to surfaces (and form biofilms). Microorganisms adhere to surfaces poorly in shear stresses.

There is no shear where there is no water movement (shear increases with the speed of flow).

3. Avoid standing water by staying away from certain regions:

The rule is to keep branch pipes as short as possible. A correct drainage slope can also lessen the possibility of pollution.

4. Avoid leakages:

Filters on the air vents of storage tanks should be installed to stop the entry of airborne microorganisms. Even holding them under a “blanket” of an inert gas like nitrogen is an option.

5. Distribution and storage at high temperatures:

The hazards of endotoxin-shedding biofilms are deemed to be so serious that most manufacturers demand that the temperature of storage and distribution be kept above 65°C notwithstanding the best efforts at control described above.

However, it should be remembered that 65 °C is too high a temperature for the majority of pharmaceutical formulation applications. This means that cooling mechanisms of some kind are typically present in user points.

6. When necessary (and to avoid the risk of toxic materials seeping), coated surfaces can be used on pipelines and in tanks to combat biofouling.

Bacteria can cause breakdowns, downtime, and production problems in industrial water purification systems. Fortunately, there are numerous ways to avoid germs in the water. They all demand rigorous planning and close system supervision.

1. Testing regularly:

Microbiologists can perform an oxidase test to determine whether or not there is any bacteria present. It checks to see if glucose is the source of any CO2 gas production. There is a substantial likelihood of bacterial contamination if the CO2 levels are lower than expected.

2. Properly disinfecting the water system:

Frequent disinfection is a necessary aspect of maintaining a water system. Your industrial water purification system can be properly disinfected and free of impurities by hiring a team of experts to maintain it.

3. Membrane durability:

In reverse osmosis purification systems, routine membrane cleaning can help avoid bacterial infection and increase the durability of the membrane.

4. Maintenance:

Check the water pump to make sure the water is moving at the proper speed. Bacteria can develop in a slow water supply without the necessary turbulence.

5. Maintenance of the devices:

1. Maintenance Of Pre-treatment Devices:

a. Filters:

The backwash procedure aims to guarantee that any clogged slime and other contaminants are eliminated from the system before they contaminate microorganisms.

b. Resin Tank:

The resin tank should be positioned out of the direct path of the sun because this promotes bacterial growth.

c. Security Filter:

If the gap between the intake and output water exceeds 0.06 MPA, the security filter’s filter element needs to be replaced. Depending on the quality of the water, the element filter should be changed every two to three months.

2. Maintenance of Ultrafiltration (UF) Systems:

The UF system includes delicate membranes that must be cleaned frequently to keep them clear of microorganisms. 

The sterilizing procedure, though, is dependent on whether the system is designed to remove organic or inorganic impurities or a mix of both.

3. UF Systems Cleaning:

A low and a high alkaline cleaning agent, with concentrations of 0.06 percent and 1 percent, should be used to clean the tubular membranes. Clean in place (CIP) is the process, and it lasts for 40 to 60 minutes.

Caustics, chelating, and surfactant agents are a few of the chemical cleaning agents you can utilize on membranes.

4. Cleaning Inorganic UF Systems:

Inorganic UF systems can be cleaned most effectively with citric acid at a 3 percent concentration. You can also utilize hydrochloric, nitric, sulfuric, oxalic, and nitric acids. 

The cleaning procedure should last between one and three hours to remove any inorganic contaminants.

5. Maintainance of the Reverse Osmosis System:

Depending on the source of contamination, antibacterial cleaning of RO membranes is a must. If the water recovery rate falls below 70%, it is a sign that your RO membranes need cleaning or replacement. 

1. Concrete Flushing:

Water can be flushed out at very high speeds to remove any particles that have only adhered to the membranes and not the feed side of the system.

2. Chemical Cleaning:

With this technique, the membranes are soaked in chemicals. The leftover germs are subsequently removed from the membranes using a flush.

3. Backward Flushing:

To get rid of any bacteria that may have become lodged in the membrane pores, reverse filtration is used.

Conclusion:

Microbial adhesion will cause biofilm formation in pharmaceutical water-distribution systems, which will worsen water pollution, lower the visual quality of potable water, speed up pipe corrosion, and lower microbiological safety since pathogen survival is increased.

Therefore, engineers, workers in production, and microbiologists are concerned about microbial control.

This article included an overview of the design, management, and production of pharmaceutical-grade water, as well as the microbiology of water systems.

While many design and control factors have been covered, the two that stand out as crucial are avoiding stagnant water (which is always a source of contamination) and having sanitization options available at every stage of the water system.

At Aquamech, in addition to helping you in selecting the ideal system for your requirements, we also offer routine maintenance. Feel free to contact our design head Navdeep Singh Sethi if you’d like more information about our services and bacteria avoidance in the purification systems or email us at hipurity@aquamech.co.in.