Reactor Systems Drying the Exhaust Inside a Bioreactor So Its Filters Stop Clogging

This patent describes an improvement to the large vessels used to grow cells and microbes for medicine manufacturing. It condenses moisture out of the exhaust gas inside the vessel’s own headspace, so the exhaust filters do not become waterlogged. It comes from ABEC, Inc., a Pennsylvania company that has been building fermenters and bioreactors since 1974.

The Problem

Most modern medicines made from living cells, from vaccines to monoclonal antibodies, are produced inside a bioreactor: a large sealed vessel in which mammalian, insect, plant or microbial cells are cultured under carefully controlled conditions. Increasingly these vessels use a disposable plastic liner, a single-use container, rather than a stainless steel tank that has to be cleaned and sterilised between batches.

Cell cultures are warm and wet, so the gas leaving the vessel is close to saturated with water vapour. That gas has to pass through a sterile exhaust filter before it can be released. When warm, humid air hits a filter it condenses, and a wet filter chokes. Pressure builds inside the vessel, which is dangerous for a thin plastic liner, and operators are forced to oversize filters, add heaters, or bolt on a separate external condenser unit with its own tubing and pumps. Each of those workarounds adds cost, adds points of failure, and puts stress on the upper section of the disposable bag, particularly at seams and welds.

What This Invention Does

Instead of treating the moisture downstream, the invention removes it inside the vessel. A jacketed and enclosed holder cools the upper part of the container so that the headspace, the empty space above the culture, is held at a lower temperature than the reaction mixture below it. That temperature difference turns the headspace itself into a condenser. Water vapour rising off the culture condenses against the cool upper wall and drips back down, so the gas that finally reaches the exhaust filter is far drier and the filter stays clear.

The disclosure describes this as a headspace condenser, and pairs it with coalescing devices: serpentine channel units that merge fine droplets in the exhaust stream into larger ones that are easier to remove, with optional points at which heated air can be introduced into the exhaust line. Because the holder works across two zones, one cooling the headspace and one servicing the reaction volume, a single piece of equipment handles both the culture temperature and the humidity control, removing the need for the separate external condensers used in competing systems.

Key Features

• Headspace condensation. The vessel’s own headspace is cooled to condense fluid out of the gas before it reaches the filter.
• Two-zone jacketed holder. An enclosed holder removes heat across two zones, controlling the headspace and the reaction volume separately.
• Reduced filter load. Drier exhaust means less load on sterile exhaust filters and fewer blockages.
• Coalescing devices. Serpentine-channel coalescer units merge fine droplets in the exhaust stream so they can be removed.
• Optional exhaust heating. Heated air can be introduced at defined points in the exhaust path to further suppress condensation.
• Disposable container support. The design reduces stress on single-use plastic containers, including at films, seams and welds.

Who Is Behind It

The applicant is ABEC, Inc. of Bethlehem, Pennsylvania, a supplier of single-use, stainless steel and hybrid bioprocess equipment to the biopharmaceutical industry, with manufacturing in the United States and Ireland. The named inventors are Eric Rudolph and Pete Silverberg. The application is a divisional of Australian application 2020214343 and claims priority from a United States provisional filed on 1 February 2019.

Why It Matters

Biopharmaceutical manufacturing is capacity-constrained and expensive, and a large share of the cost sits in equipment that has to run sterile for weeks at a time. An exhaust filter that blocks part-way through a campaign can cost a full batch of product worth millions. Australia has a substantial biologics manufacturing base, including vaccine and plasma production, so equipment improvements that raise reliability and lower the amount of ancillary hardware around each vessel have direct relevance here. Filing in Australia gives ABEC protection in a market where its customers install this class of equipment.

Related Concepts

• Bioreactor – the vessel this invention improves.
• Condensation – the physical process the headspace condenser exploits.
• Biopharmaceutical – the class of medicines made in these systems.
• Cell culture – the process running inside the reaction container.
• Sterile filtration – the exhaust filtering step protected by drier gas.
• Coalescer – the droplet-merging device used in the exhaust path.

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AU 2026202026 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.