Ordering a custom glass reactor involves more than selecting vessel capacity, temperature range, and motor power.
The reactor must also match the process materials, operating sequence, feeding method, mixing requirements, condenser arrangement, cleaning method, and available installation space.
From HJCHEM’s experience, a clear technical checklist helps to select the right vessel structure, agitator, ports, seals, temperature-control unit, and supporting equipment before production begins.
This guide explains the information buyers should prepare when requesting a custom glass reactor and how each parameter affects the final design.
What Process Information Should Be Defined First?
We should explain:
- the basic purpose of the reactor
- the materials added to the vessel
- the general reaction sequence
- whether the process is batch, semi-batch, or continuous
- whether solids are involved
- whether reflux, distillation, crystallization, filtration, or gas introduction is required
- how the final product will be discharged
A short process flow is usually more useful than a general statement such as “chemical synthesis” or “pilot reactor.”
For example:
Add solvent → start stirring → heat to 80°C → add powder → dose reagent over two hours → hold for four hours → cool → discharge.
This simple description helps HJCHEM determine the required feed ports, temperature-control method, agitator, condenser, bottom outlet, and control sequence.
How to Specify Reactor Capacity ?
We should clarify whether the volume means total volume or working volume.
1. Total Vessel Volume
The total volume is the internal geometric capacity of the vessel.
2. Normal Working Volume
The normal working volume is the actual liquid volume during routine operation.
For many liquid-phase reactions, the working volume may be approximately 70–80% of the total vessel capacity. However, the correct filling ratio depends on:
- foaming
- gas generation
- boiling or reflux
- powder addition
- agitation intensity
- vacuum operation
- required vapor space
A process involving foam or rapid gas release may require significantly more free space.
3. Minimum Working Volume
Minimum volume is also important because temperature probes, pH sensors, feed pipes, and agitator blades must remain correctly positioned in the material.
We should provide:
- total batch volume
- normal working volume
- minimum working volume
- maximum expected liquid volume
- expected volume increase during feeding
For pilot reactor, capacity should not be selected only by multiplying laboratory volume. Mixing, heat transfer, feeding time, and discharge become more difficult as the reactor becomes larger. These factors are discussed in our glass reactor scale-up guide.
What Materials Will Contact the Reactor?
We should provide complete material list when selecting wetted parts.
This includes:
- raw materials
- solvents
- acids
- alkalis
- catalysts
- salts
- cleaning agents
- reaction intermediates
- final product
- expected by-products
We should also provide concentration and operating temperature because chemical compatibility can change with both.
1. Glass Vessel Compatibility
Borosilicate glass offers broad resistance to many solvents, acids, and chemical mixtures, but it is not suitable for every material.
Particular attention is required for:
- hydrofluoric acid
- fluoride-containing media
- hot concentrated alkalis
- strong phosphoric acid at elevated temperature
- highly abrasive slurries
- sudden temperature changes
2. Other Wetted Components
Besides the glass vessel, the complete reactor also contain:
- PTFE
- stainless steel
- mechanical-seal materials
- O-rings
- valve seals
- pump tubing
- condenser connections
- sensor bodies
The material review should cover the entire system rather than only the vessel.
Our article on glass reactor chemical resistance provides a broader overview, but final compatibility should always be checked against the actual process conditions.
What Temperature Range and Control Accuracy Are Required?
We should specify three different temperature values:
- normal operating temperature
- minimum and maximum design temperature
- required temperature-control accuracy
For example, a process may normally run at 80°C but require cooling to 5°C before discharge. Another process may operate at −40°C and need a temperature-control unit capable of both cooling and heating.
1. Jacket Configuration
HJCHEM can configure reactors with:
- single-wall vessels
- double-wall jacketed vessels
- triple-wall vessels with an external vacuum or insulation layer
Double-wall reactors are commonly used for circulating heating or cooling fluid. Triple-wall construction can reduce condensation and frost during low-temperature operation.
2. Temperature-Control Unit
The circulator should be selected based on:
- reactor volume
- material volume
- required temperature range
- heating and cooling rate
- material heat capacity
- reaction heat
- jacket volume
- pressure limit of the glass jacket
- ambient conditions
A circulator with a wide temperature range is not automatically powerful enough for the process. Heating capacity, cooling capacity, pump flow, and pump pressure must also be checked.
Our circulator selection guide explains the main sizing factors.
3. Temperature Measurement
We should confirm whether the control signal comes from:
- jacket-fluid temperature
- reactor material temperature
- both material and jacket temperature
Direct material-temperature feedback is generally more representative for reaction control.
Does the Reactor Need Vacuum or Positive Pressure?
Most laboratory and pilot glass reactors are designed for vacuum operation and normal pressure.
We should state:
- normal operating pressure
- maximum vacuum level
- whether vacuum is continuous or intermittent
- whether the vessel may experience positive pressure
- whether gas is introduced
- whether pressure may rise during heating or reaction
1. Vacuum Requirements
Vacuum performance depends on the entire system, including:
- glass joints
- mechanical seal
- valves
- feed funnels
- condenser
- receiver
- hoses
- vacuum pump
More ports and accessories create more potential leakage points.
Correct glass reactor seals are therefore important when deep vacuum or long holding time is required.
2. Positive Pressure
A glass reactor should not be treated like a metal pressure vessel. If the process requires significant positive pressure, a stainless steel or alloy pressure reactor is more appropriate.
The maximum allowable pressure must be confirmed for the selected vessel and accessories before operation.
How to Choose Agitation System?
The correct agitator depends on material behavior rather than reactor volume alone.
We should provide:
- viscosity
- solids content
- particle size
- risk of settling
- foaming tendency
- required rotational speed
- required mixing purpose
- whether gas dispersion is required
- whether wall scraping is needed
1. Common Agitator Functions
Different impellers may be selected for:
- general liquid mixing
- solid suspension
- gas-liquid dispersion
- crystallization
- high-viscosity blending
- heat-transfer improvement
- gentle mixing
- axial circulation
For high-viscosity materials, a standard small PTFE impeller may not provide enough circulation. An anchor, frame, helical, or scraper agitator is required.
2. Baffles
Internal baffles can reduce bulk liquid rotation and improve top-to-bottom mixing.
They are useful for:
- multiple-feed reactions
- precipitation
- crystallization
- solid suspension
- processes with strong vortex formation
The number, width, material, and position of the baffles should be coordinated with the agitator. Our article on glass reactor baffles explains their effect in more detail.
How Many Lid Ports Are Required?
A standard HJCHEM glass reactor lid normally uses six ports for the main functions:
- agitation
- temperature measurement
- solid charging
- liquid feeding
- controlled dosing
- reflux or distillation
However, custom processes also require:
- pH sensor
- gas inlet
- vent
- ultrasonic probe
- CIP spray device
- vacuum connection
- sampling port
- conductivity sensor
- additional feed pumps
- rectification column
- pressure instrument
- liquid-level measurement
We should provide a complete accessory list rather than requesting only “six ports” or “eight ports.”
Port design must also consider:
- opening diameter
- glass-joint or flange type
- nozzle position
- accessory height
- insertion depth
- clearance between components
- maintenance access
A lid may have enough ports but still be difficult to operate if the condenser, motor, feed funnels, and sensors interfere with one another.
Is Reflux, Distillation, or Rectification Required?
These functions require different glassware configurations.
1. Reflux
A reflux condenser returns condensed vapor to the reactor.
We should provide:
- boiling temperature
- cooling-water temperature
2. Distillation
A distillation configuration sends condensed solvent to a receiving vessel.
It may require:
- condenser
- vacuum line
- receiving flask or tank
- receiver switching
- bottom discharge
- cold trap
3. Rectification
Fractional distillation may require:
- packed column
- structured or random packing
- reflux divider
- top condenser
- multiple receivers
- column temperature points
- vacuum control
A tall column should have independent support rather than relying only on the glass reactor lid.
How Will Solids Be Added and Discharged?
Solids can significantly affect reactor design.
We should describe:
- solid type
- particle size
- bulk density
- quantity per batch
- whether the solid is dusty
- whether it tends to bridge
- whether it is added before or during reaction
- whether solid residue remains after the process
1. Solid Charging
A larger solid charging port is needed for powders, crystals, catalysts, or plant materials.
2. Bottom Discharge
The discharge valve should be selected according to:
- product viscosity
- particle size
- solids concentration
- risk of blockage
- required drainage
- downstream pipe diameter
A small bottom valve may be sufficient for clear liquid but unsuitable for slurry or crystal discharge.
3. Vessel Access
For processes requiring frequent residue removal, HJCHEM design and manufacture a liftable or tilting vessel arrangement. A liftable glass reactor can provide better access for charging, rinsing, discharge, and manual cleaning.
How to Clean the Reactor ?
The cleaning method should be considered before the lid and frame are finalized.
Possible methods include:
- manual rinsing
- solvent circulation
- spray-ball cleaning
- CIP cleaning
- vessel lowering
- vessel tilting
- partial disassembly
- complete agitator removal
We should explain:
- cleaning frequency
- cleaning liquid
- cleaning temperature
- whether the cleaning solution is recovered
- acceptable residue level
- whether product cross-contamination is critical
- whether operators need direct access to the vessel
A fixed-frame reactor is adequate for simple liquids but less convenient when sticky or solid material remains inside the vessel.
We should consider regular glass reactor maintenance when planning seals, valves, removable parts, and cleaning access.
Custom Glass Reactor RFQ Checklist
The following checklist can be copied directly into an inquiry.
1. Capacity
- Required total volume:
- Normal working volume:
- Minimum working volume:
- Maximum working volume:
2. Operating Conditions
- Normal temperature:
- Minimum temperature:
- Maximum temperature:
- Working pressure:
- Required vacuum level:
3. Mixing
- Material viscosity:
- Solids concentration:
- Required stirring speed:
- Preferred agitator:
- Baffles required:
- Wall scraper required:
4. Feeding
- Number of feed streams:
- Feed materials:
- Flow range:
- Dosing accuracy:
- Manual or automatic control:
- Solid charging method:
5. Process Functions
- Reflux:
- Distillation:
- Rectification:
- Gas inlet:
- Vacuum:
- pH measurement:
- Ultrasonic treatment:
- CIP cleaning:
- Filtration:
6. Discharge
- Product form:
- Viscosity:
- Solids or crystals:
- Vessel lifting or tilting required:
7. Utilities
- Voltage:
- Frequency:
- Electrical phase:
- Cooling water:
- Chilled fluid:
- Compressed air:
- Nitrogen:
8. Installation
- Available floor space:
- Maximum equipment height:
- Doorway dimensions:
- Fume hood dimensions:
- Hazardous-area requirements:
9. Control
- Manual or PLC/HMI:
- Parameters to control:
- Parameters to record:
- Alarm requirements:
- Data export required:
Conclusion
A successful custom glass reactor project begins with complete process information.
We should define:
- actual working volume
- material compatibility
- temperature and pressure
- mixing requirements
- port functions
- feeding method
- condenser configuration
- discharge and cleaning
- instrumentation
- utilities and installation limits
The objective is not to add as many options as possible. It is to build a reactor system in which every vessel, port, pump, sensor, valve, and accessory has a clear process function.
Planning a Custom Glass Reactor Project?
Send HJCHEM your process description, batch volume, materials, operating conditions, mixing requirements, feed arrangement, and site utilities.
Our team can review the information and prepare a suitable custom glass reactor configuration for laboratory or pilot-scale use.