All-in-One Guide to Fermenter/Reactor Valve Selection

In biomanufacturing applications, fermenters and bioreactors play a central role in biochemical reactions, and the selection of valves for the associated piping systems is a critical factor in ensuring aseptic processes and controlling fluid conditions. This article provides an overview and discussion of commonly used valves for fermenters and bioreactors.

First, let’s clarify several general core criteria for valve selection:

Functional Requirements: This is the primary consideration. First, determine whether the valve is intended for shutoff, pressure/flow regulation, anti-mixing, sampling, venting, backflow prevention, safety relief, or other purposes.

Sterility and Cleanability: For applications requiring sterility and cleanliness, valve designs must be free of dead spaces, fully drainable, have smooth internal surfaces, and be capable of withstanding high-temperature, high-pressure steam (typically above 121°C) during Clean-in-Place (CIP) and Sterilize-in-Place (SIP) processes.

Material Compatibility: The materials used for the valve body and seals must be resistant to the culture medium, acidic and alkaline cleaning solutions (such as NaOH and H₃PO₄), and steam corrosion. For example, 316L stainless steel is a common standard material for valve bodies. Sealing diaphragms and gaskets are typically made of EPDM, silicone rubber, FKM (Viton), PTFE, and other materials.

Maintenance Considerations: Many valves require disassembly for inspection and periodic replacement; therefore, factors such as installation space, connection methods, and ease of maintenance must be taken into account.

Appendix: GMP-Related Provisions

Article 71: The design, selection, installation, modification, and maintenan

ce of equipment must be suitable for its intended use, minimize the risk of contamination, cross-contamination, mix-ups, and errors as much as possible, and facilitate operation, cleaning, maintenance, and, when necessary, disinfection or sterilization.

Article 74: Production equipment shall not adversely affect the quality of drugs. The surfaces of production equipment that come into direct contact with drugs shall be smooth, clean, easy to clean or disinfect, and corrosion-resistant; they shall not react chemically with drugs, adsorb drugs, or release substances into drugs.

Article 79: The maintenance and repair of equipment shall not affect product quality.

Valve Configuration in Fermenters/Reactors

I. Gas Inlet System

In microbial and cell culture processes, a continuous gas supply is required in the vast majority of scenarios. Different gas types are selected based on culture requirements: aerobic cultures typically use air, oxygen, or carbon dioxide, while anaerobic cultures require inert gases such as nitrogen. The core function of the gas inlet system is to precisely regulate the flow rates of various gases to meet the gas supply requirements of different culture conditions.

II. Exhaust System

Complementing the gas supply system, this system handles exhaust gas treatment and vessel pressure control during the culture process. Exhaust gas treatment typically involves processes such as condensation and reflux, heating, and filtration. The system also includes ports for exhaust gas analysis to facilitate real-time monitoring of exhaust gas composition. Stable control of vessel pressure is integrated into this system to ensure the culture environment meets pressure specifications.

III. Feed System

As one of the core systems for microbial and cell culture, it accommodates the feeding requirements of the vast majority of culture scenarios. It can perform continuous in-process feeding, defoamer addition, and the dosing of various substances requiring a single-dose addition, precisely matching the dynamic demands for nutrient supply and environmental control during the culture process, which directly impacts culture efficiency and the quality of the target product.

IV. Jacket System

This system serves as the core unit for vessel temperature control and the heating phase of in-line sterilization (SIP), playing a critical role. On the one hand, it maintains a stable tank temperature throughout the culture process, ensuring the temperature remains within the optimal range for microbial and cell growth; on the other hand, it handles the heating function during the SIP process (some designs rely entirely on the jacket for SIP), ensuring effective sterilization and mitigating the risk of contamination by foreign microorganisms.

V. Tank Bottom System

This is an indispensable functional system that primarily performs two core tasks: first, the harvest and discharge of the target product upon completion of the culture; second, the discharge of wastewater during the tank cleaning process, ensuring equipment cleanliness and compliance for subsequent cultures.

VI. Sampling System

This is a standard system in fermentation and cell culture processes, responsible for process sampling—through sampling, key indicators such as the composition of the culture medium and microbial concentration can be monitored in real time, providing data support for process adjustments and serving as a critical link in ensuring the controllability of the culture process.

VII. Waste Discharge System

This essential system is responsible for the centralized discharge of various types of wastewater and condensate, including jacket drainage, steam condensate, biological wastewater, and routine production wastewater. It prevents equipment damage or environmental impact caused by the accumulation of waste liquids and ensures the smooth progression of the production process.

VIII. Utility Systems

These systems serve as the power backbone for the entire fermentation/cell culture tank system, supplying all necessary utility media. This includes process water such as cooling water, chilled water (inlet and return), hot water (inlet and return), softened water, and deionized water; sterilization and heating media such as industrial steam and clean steam; as well as gaseous media such as air, oxygen, carbon dioxide, and nitrogen—all tailored to meet the operational and process requirements of each system.

IX. CIP Inlet and Return Piping System (Optional)

Installed only when the equipment is configured with a Clean-in-Place (CIP) function. It includes inlet and return piping to enable automated cleaning of tanks and piping, reducing manual labor and improving cleaning efficiency and compliance; systems without CIP functionality do not require this configuration.

X. Mechanical Seal Piping System (Optional)

This system is intended only for equipment equipped with double-face mechanical seals and includes the necessary auxiliary piping to ensure the sealing performance and service life of the mechanical seals. This system is not required for equipment that uses magnetic stirring or single-face mechanical seals.

Sterility Boundaries

Primarily, this concept provides a foundational reference for risk assessment.

As shown in the figure above: The bolded sections indicate the aseptic boundary.

Based on the documentation, the general principles for this section are as follows:

Design and manufacture systems capable of effectively controlling bioburden.

All connections must be capable of CIP and SIP.

Other requirements include drainability, elimination of dead spaces and crevices, material surface finish, and so on.

Understanding these fundamentals provides a basis for reference when selecting valves for this application.

Fermentation Tank Application Scenarios

The following sections will describe the application scenarios for fermentation valves in the following order:

01. Valves for aseptic interface systems

02. Bottom tank valves

03. Sampling valves

04. Valves for jacket systems

05. SIP condensate drainage—steam traps

06. Inlet gas flow control—MFC/proportional control valves

07. Tank pressure control—proportional control valves

08. Feed Flow Control—Proportional Control Valves

09. Steam Flow Control—Steam Proportional Control

10. Air and Steam Pressure Reduction—Pressure Reducing Valves

11. Check Valves—Check Valves

12. Utility Systems—Shut-off Valves

13. Safety-Related—Safety Valves

14. Other System Valves

Introduction to Common Valve Selection for Fermenters/Reactors

01 The Top Choice for Aseptic Systems—Diaphragm Valves

Diaphragm valves are widely used in standard fermenter/reactor systems.

Figure 2: Schematic of a Diaphragm Valve

From a cleanliness perspective, diaphragm valves offer unmatched advantages: only the valve body and diaphragm come into contact with the process medium, while the rest of the valve is completely isolated, allowing for thorough sterilization of the valve using steam.

Operating Principle: Driven pneumatically or manually, the valve opens, closes, or regulates the flow by compressing or lifting an elastic diaphragm (such as EPDM or PTFE). The operating mechanism is completely isolated from the process flow path, eliminating the risk of contamination via the valve stem.

Structural Types:

Weir-type: The most common. Its flow characteristics are similar to those of a quick-opening valve, making it suitable for shutoff and coarse regulation. It facilitates CIP/SIP.

Straight-through type: The flow path is unobstructed, resulting in low pressure drop. It is particularly suitable for the discharge of viscous fluids, slurries, or culture media containing solid particles.

Summary of Diaphragm Valves

The preferred choice for aseptic systems, as detailed in the second section on specific applications.

Scope of Application: Primarily distributed as follows:

2.1 Inlet gas lines—at least downstream of the filter

2.2 Exhaust gas lines—at least upstream of the filter

2.3 All feed line valves (including inoculation)

2.4 Material distribution lines

2.4 Bottom-of-tank material transfer lines

2.5 CIP supply and return lines

Branch valves, block valves, T-valves, multi-channel valves, etc.

These valves are also types of diaphragm valves. For example, multi-channel valves combine multiple valves into a single multi-channel body, saving space and significantly reducing residual media in the fluid system. Additionally, T-valves and block valves feature a zero-dead-space design, among other features.

Figure 3   Schematic of T-Valves, Block Valves, and Multi-Channel Valves

These are also used in fermenters and bioreactors; below are some photos taken during actual applications.

T - valve installed at the bottom of a fermenter—for drainage

Figure 4  Application of T-Valves in Fermenter Bottom Valves

Note: T-valves are widely used in U-bends in water systems

Multi-channel valves used in feed systems

Figure 5: Reference for Configuration Options in Feeding Systems

Multi-channel valves used in feeding systems

Figure 6: CIP System Block Valve Reference

For this type of valve:

1. It offers many advantages, such as:

a. Simple implementation of complex flow paths

b. Maximum space and weight savings

c. Improved cleanability and sterility

d. Simplified maintenance and enhanced reliability

2. Conventional fermentation system designs are expensive and should be selected based on product process and value requirements.

3. In any case, selecting the right valves is only part of the equation; a systematic, holistic design approach is essential!

Extensions—GMP valves, SAP valves, etc.—these valves are also classified as diaphragm valves.

Figure 7: Illustrations and Explanations of GMP Valves/SAP Valves

There are two types of GMP valves: one is a combination valve with a 90° elbow, and the other is a combination valve with a valve-to-valve connection. In the valve-to-valve connection configuration, one valve is positioned horizontally and maintained at a specific self-draining angle; the other valve is a vertically mounted main valve. When this valve is open, its outlet serves as a sampling port free from bacterial growth.

SAP valves are primarily used in horizontal piping systems, where the main valve must be installed horizontally and maintained at a specific self-draining angle, with the branch port located at the lowest drainage point of the main valve’s horizontal run. The SAP configuration can consist of a main valve combined with a branch pipe, or a main valve combined with a branch valve installed either vertically or horizontally; this configuration is frequently used for partial condensate drainage and sampling.

Figure 8: Schematic of a Reference Valve

There are also many other types, such as the I-BODY valve, but they will not be listed here.

02 Tank Bottom Valves

Some common tank bottom valves are a special type of diaphragm valve.

Tank bottom valves are typically welded to the bottom of the tank and serve as discharge valves (one per tank). This allows the medium inside the tank to be drained, cleaned, and sanitized.

Figure 10: Schematic of a Common Fermenter Bottom Valve

03 Fermentation Broth Sampling—Sampling Valve

Sampling valves are a relatively specialized type of valve used for process sampling from fermenters and reactors:

There are two common types:

1. The first common type is recommended to be SIP-capable; as shown in the figure below, the dual-port sampling valves design is the most widely used:

Figure 11: Common Types of Dual-Port Sampling Valves

1. There are also disposable sampling products available, which can be used when stricter sterility control is required. These use needle-puncture sampling and have a limited number of uses.

Figure 12: Schematic of a Disposable Sampling Valve

Summary of Sampling Valves

For sampling lines in fermentation tank systems, it is recommended, as shown earlier, that they be equipped with SIP. It is unacceptable for sampling ports to be designed without sterilization capabilities, or for those equipped with SIP to be left unsterilized during actual operation, or for samples to be taken immediately after a brief rinse.

Sampling procedures for contamination investigation must be incorporated into the troubleshooting process.

CIP is generally not required for sampling system piping.

For aseptic sampling, a dedicated aseptic sampling device must be configured. The operating principle is as follows:

Figure 13: Schematic Illustration of the Principle of Aseptic Sampling

4. Aseptic sampling devices can include pneumatic systems, multi-channel valves, and other options, depending on actual requirements. As shown in the figure below.

Figure 14: Schematic of a Sterile Sampling Unit

5. The interface of the sampling valve and its contact with the interior of the tank are designed to eliminate dead spaces. For in-vessel sterilization of the fermentation tank, it is not necessary to introduce steam into the tank to sterilize the sampling port.

Note: However, if steam introduction into the tank does not cause violent agitation, it can be used as an additional measure.

04 Jacket Systems—The Main Application for Angle Seat Valves

Angle seat valves are the second most commonly used valves in fermentation tanks and reactor systems.

The valve plug (typically conical or flat) of an angle seat valve is driven by a pneumatic or electric actuator within a right-angle flow path, performing linear motion to open and close the valve. Its flow path design helps reduce fluid resistance.

Figure 15 Schematic of a Common Angle Seat Valve

Key Features:

Compact Design: The right-angle design saves installation space.

Fast Response: Pneumatic angle seat valves, in particular, are suitable for automated applications requiring rapid shutoff.

Excellent Sealing Performance: The valve plug and seat typically feature a face seal, ensuring a high level of leak tightness.

Adjustability: Some designs can be used for flow regulation, but their primary advantage lies in on/off control.

Summary of the Angle Seat Valve Series

Widest Range of Applications: Angle seat valves are recommended for standard jacketed system valves and are currently the most mainstream design. Angle seat valves offer certain design advantages when dealing with impact forces such as water hammer in jacketed systems.

Figure 16  Schematic of a Jacketed Angle Seat Valve

2. Specific applications are not limited to the following common examples:

    2.1 Chilled water supply and return valves

    2.2 Air inlet valve near the jacket

    2.3 Steam inlet

    2.4 Jacket drain

    2.5 Valve before the steam trap

    2.6 Circulation shut-off valve etc.

1. Angle seat valves can also be used for other applications where there is no contact with the process medium, such as exhaust gas condensers.

Figure 17: Schematic of the Exhaust Gas Condenser Inlet and Return Valves/Drain Valves

4. For the non-sterile side of the inlet piping, based on the concept of sterile interfaces mentioned earlier, angle seat valves may be used depending on the specific project circumstances. This decision is based on risk assessment.

5. Pay attention to the installation orientation; install strictly according to the arrow direction on the valve body. Angle seat valves must not be installed backwards. Most angle seat valves have asymmetrical seals; installing them backwards will result in: failure to seal properly, internal leakage, a sharp decrease in service life, and even damage to the valve plug. This is especially critical for steam and high-temperature gas lines.

05 Condensate Drain Lines—Condensate Traps

Regarding fermenter condensate drain lines, the use of condensate traps is a growing trend and a common practice. They are primarily used in fermenter steam sterilization (SIP) and heat tracing/insulation lines to rapidly drain condensate, prevent the leakage of sterile steam, ensure sterilization temperature, pressure, and a sterile environment, while also avoiding water hammer, pipeline corrosion, and the risk of contamination.

Figure 18: Common Types of Steam Traps

Commonly selected types include thermostatic steam traps (which operate based on thermal expansion and contraction), such as the common “small flying saucer” model.

Figure 19 Schematic of the Internal Structure of a Thermostatic Steam Trap

Summary of Steam Traps

Regarding the drainage of sterilization steam, many people tend to slightly open the manual steam vent valve to adjust the steam discharge, feeling reassured only when steam is visible, out of concern that the steam trap may not fully drain the system. In reality, this is not a problem as long as the selection and calculations are appropriate. Fully automatic, one-button SIP is also a growing trend.

Drain lines equipped with steam traps must not be used to discharge CIP return or other wastewater.

06 Inlet Flow Control—Proportional Control Valve

There are typically several methods for inlet flow control:

1. For low flow rates, integrated control and sensing units are commonly used; MFCs are frequently employed.

Figure 20  MFC Schematic

Thermal mass flow meters are generally used; for large-volume tanks, a flow meter combined with a proportional control valve is typically employed.

Figure 21  Reference for Proportional Control of High-Flow Air

07 Tank Pressure Control—Proportional Control Valve

Figure 22 Schematic of the Exhaust Gas Proportional Control Valve

Summary of the Exhaust Gas Proportional Control Valve

The inlet controls the flow rate, the exhaust gas controls the tank pressure, and the pressure is regulated via venting.

If steam sterilization is required, be sure to select a high-temperature-resistant model.

The KVS value is critical.

It is best to select a range within the control range of 30–70%.

Some systems use on/off valves with pulsed opening to control tank pressure; this is acceptable for applications with less stringent requirements.

08 Feed Flow Control—Proportional Control Valve

For feeding into large-capacity tanks, the following configuration is commonly used:

Flowmeter (e.g., electromagnetic) + proportional control valve

Figure 23  Common Control Methods for Rigid Pipe Feeding

Note: Flow control for small tanks typically uses peristaltic pumps (or, in some cases, metering cups), but since these are not valves, they are not covered here.

Figure 24 Schematic of a Feed Proportional Control Valve

09 Steam Flow Control—Proportional Control Valves

In some fermenter systems, steam supplied to the jacket and the vessel body is controlled using proportional control, which offers greater accuracy.

The key to steam proportional control is precision, stability, and reliability. In most industrial applications, single-seat globe valves with linear-characteristic sleeve valve trims are a common choice.

Summary of Steam Proportional Control Valves

For steam inlet valves to the fermenter, proportional control is not always necessary for precise regulation; maintaining the steam inlet pressure at a stable value is also a common strategy. This approach is employed in many designs, and the ideal scenario is for the steam pressure limit to exactly meet the sterilization temperature requirements when the system reaches a steady state. Particularly in feed tank systems, SIP control is typically based on steam line pressure control.

10 Air and Steam Pressure Reduction—Pressure Reducing Valves

Air Pressure Reducing Valves

Air entering the fermenter typically needs to be reduced in pressure and limited to a range such as 1.6–2.0 kg.

Air pressure reducing valves are used for this purpose.

Figure 25 Schematic of a Common Air Pressure Reducing Valve

Additional Notes on Air Pressure Reducing Valves

1. Vertical Installation Requirements

The valve must be installed vertically with the condensate drain port facing downward. Horizontal or inverted installation is prohibited, as this may prevent condensate from draining, cause the filter element to clog, or result in diaphragm failure. In special cases where an angled installation is necessary, the angle should not exceed 30°, and the drain port must still remain at the lowest position.

2. Principles for Location Selection

Install close to the point of use to minimize pressure loss in the piping.

Install in a location that facilitates operation, inspection, and maintenance, with the pressure gauge oriented for easy reading.

Avoid sources of vibration, high-temperature areas, and corrosive environments; install vibration-damping brackets if necessary.

Allow sufficient maintenance space (≥150 mm above, below, and on all sides) to facilitate filter element replacement and drainage operations.

3. Flow Direction

Strictly follow the arrow markings on the valve body (IN→OUT). Reverse installation is prohibited, as it may cause the valve plug to jam, lead to uncontrolled pressure, or even damage internal components.

Steam Pressure Reducing Valve

Steam entering the fermentation tank typically requires pressure reduction, usually limited to 1.1–1.5 kg (depending on actual conditions).

Therefore, a steam pressure reducing valve is used.

Figure 26: Schematic Diagrams of Conventional Pressure Reducing Valves and Clean Steam Pressure Reducing Valves

Additional Information on Steam Pressure Reducing Valves

Clean steam requires the use of clean steam pressure reducing valves, which are very expensive. This is also one of the main factors contributing to the price difference between some GMP equipment and GLP components.

General-purpose steam: Cast steel (WCB)

Clean / Food / Pharmaceutical: Stainless steel (CF8/CF8M)

High Temperature and High Pressure: Heat-resistant steels such as chromium-molybdenum steel.

It is recommended to install steam traps on the piping upstream of the pressure-reducing valve and at low points to drain condensate and prevent water hammer.

There are also many installation requirements, including specifications for straight pipe runs upstream and downstream; common requirements include ≥10DN upstream and ≥5DN downstream. If steam flow is unstable, review the piping design.

Do not reverse the flow direction; the arrow on the valve body must align with the steam flow direction. This has actually occurred in the past.

A pressure gauge must be installed downstream of the valve to facilitate commissioning and monitoring.

From a maintenance perspective, it is recommended to install shut-off valves upstream and downstream, or even a bypass, otherwise steam supply will be interrupted during maintenance.

It is recommended to install a filter upstream.

11 Check Device—Check Valve

Figure 27: Schematic of a Check Valve

In fermentation processes, check valves are used in the following scenarios:

Between the inlet mass flow meter and the control valve (to prevent steam from entering the mass flow meter)

Between multiple inlet gas lines, to prevent interference between different media

In multi-path exhaust systems, at the end of the exhaust line, to prevent backpressure from flowing back into the tank

Some customers require installation before the filter element and distributor in the tank air supply line to prevent material backpressure from contaminating the filter element

In certain drain line designs, to prevent contaminants from flowing back into the clean tank area, etc.

A few additional points:

The key performance parameter for exhaust check valves is the forward opening pressure. This application requires an extremely low pressure, which must be considered during selection—that is, the valve must open and allow flow under a very small forward pressure differential to reduce resistance in the exhaust system, prevent excessive backpressure, and ensure a reliable reverse seal.

In the inlet piping, check valves installed between the gas filter element and the manifold have significant shortcomings in terms of cleanliness control. This is particularly true during CIP (Clean-in-Place) procedures, when dead zones can easily form inside the valve chamber, making it difficult to thoroughly clean and sterilize the area and posing a risk of cross-contamination. From a design standards perspective, this configuration is not recommended; this principle is also consistent with the relevant requirements of the ASME BPE biopharmaceutical equipment design standard.

However, in actual engineering practice, many clients still have a critical need for physical backflow prevention. The core objective is to use mechanical structures to completely prevent process fluid from flowing back into the gas filter cartridge due to backpressure under abnormal operating conditions, thereby avoiding immersion, contamination, or damage to the filter cartridge.

For drainage systems, it is recommended to prioritize isolation methods such as water seals, air seals, and air barriers—which have no dead zones and are easy to clean—as alternatives to mechanical check valves that are prone to fouling and difficult to clean. This approach meets the requirements for backflow prevention and anti-siphoning while better adhering to the design principles of cleanliness, cleanability, and sterilizability.

Figure 28  Schematic of an Air Lock

12  Shut-off Valves for Utility Systems

Common types of valves in this category include ball valves, globe valves, and butterfly valves.

Figure 29  Schematic of Valves in the Utility System

Figure 30  Schematic of Valves in the Utility System

Figure 31  Schematic of Valves in the Utility System

Ball Valve

Figure 32: Schematic of a Ball Valve

Ball valves are quite widely used and open quickly; they are particularly suitable for small tanks and locations with limited installation space.

However, ball valves are generally not very clean, so they should not be used in piping systems with high sterility requirements.

Figure 33: Risk of Liquid Accumulation When the Ball Valve Tank Is Closed

Globe Valve

Figure 34  Schematic of a Globe Valve

Widely used

1. Globe valves are generally used to shut off steam lines; sometimes, two are connected in series as a safety measure.

2. However, they require some force to open and have a long stroke, making them unsuitable for rapid opening, etc.

Butterfly Valves

Figure 35 Schematic of a Butterfly Valve

Butterfly valves are also an option in utility systems. They are most commonly used for large-diameter valves, typically operating at pressures of 1.0 MPa or less. However, they are generally not the first choice.

Under high - pressure conditions, valves with high sealing reliability (such as gate valves, globe valves, and ball valves) should be selected; butterfly valves are not recommended.

In summary, for butterfly valves: they are the preferred choice for low-pressure, large - diameter applications requiring rough flow control.

13 Safety-Related — Safety Valves

Safety valves on fermentation tanks are overpressure safety protection devices. When the pressure in the jacket or tank exceeds the set value, they automatically open to relieve pressure, preventing tank deformation, rupture, or explosion caused by excessive pressure. Once the pressure returns to a safe range, they automatically close, ensuring the safety of both equipment and personnel during the fermentation process.

Figure 36: Schematic of a Safety Valve

Summary of Safety Valves

Burst discs are typically used on the tank body, while safety valves are used on the jacket.

Figure 37: Schematic of a Rupture Disc

They are also used on tanks (note that clean-type rupture discs must be used where cleanliness is required).

Figure 38  Schematic of a Fermenter Safety Valve

Safety valves on jacketed fermenters are typically mounted on top, though some are mounted on the bottom. In jacketed systems, water generally enters from the bottom and exits from the top, while steam enters from the top and exits from the bottom.

14  Other Valves

The following types of valves are also used in fermenter systems, though they are less common:

Feed valve — slide valve

Figure 39 Schematic of a Push Valve

Push valves are also used in some applications, but they have the following potential shortcomings:

1. The tubing connected to the push valve must be installed during the initial sterilization of the fermentation tank, which is somewhat restrictive.

2. Due to the high temperatures during the sterilization process, the tubing must be properly protected. Over time, this increases the risk of sterility failure.

Solenoid Valves

A solenoid valve works by applying an electric current to a solenoid coil, which generates a magnetic force that overcomes the pressure of a spring to move the valve spool, thereby allowing gases or fluids to pass through. They feature a simple structure and are inexpensive; however, they can only perform on/off functions and generally have a very low flow coefficient.

Solenoid valves offer a clear price advantage and are used in small fermenters.

Figure 40: Common Types of Solenoid Valves

Other Valves

1. Valves that vent gas but do not drain water are used in jackets to prevent situations such as the circulation process not being fully filled with water.

2. As mentioned earlier, there are valves for regulating steam, air, and feedstock, as well as valves for regulating water flow. Similar applications exist within jackets, but these will not be discussed in detail here.

Summary

This article provides an overview of valve selection for different operating stages in fermenters and reactors; however, it does not delve deeply into the core logic of selection or key technical parameters. The various valve drive types — such as manual, pneumatic, and electric — are also not discussed in further detail; relevant configurations must be comprehensively evaluated based on the actual operating conditions of each project. As an equipment supplier, our process engineers can collaborate with specialized valve manufacturers to finalize valve selection and confirm design solutions based on the project’s specific process requirements.