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Bulk Handling in Brewing Technology

A modern brewery processes large volumes of raw materials: barley, malt, hops, adjuncts and brewing water. Efficient bulk handling of these ingredients determines brewing quality, capacity and operational costs.

Key points

• Malt grind size determines filtration speed and extraction efficiency: too fine causes stuck filter beds, too coarse leaves sugars unused
• Hop pellets are dust-sensitive and require precise, repeatable dosing (±1-2%) for consistent bitterness
• Grain storage requires moisture control (<14%) to prevent mould growth and caking in silos
• Adjuncts such as corn grits or rice are often added via separate dosing lines to avoid cross-contamination with gluten-free brews

Malt handling: receiving to mash tun

Malt is received in bulk trucks or bags and stored in steel silos. Transport via screw conveyors to the malt mill. Malt milling is a critical process: too finely ground malt causes filtration problems; too coarse leaves starch unconverted.

Hop dosing and automation

Hop pellet dosing via weighing installations directly into the kettle or whirlpool. Hecht Technology supplies containment and big bag discharge systems for brewery adjuncts: hecht-technology.nl.

Grain transport and silo storage

Barley and malt are transferred after delivery to steel or concrete silos with capacities from a few tons to hundreds of tons. Pneumatic transport or screw conveyors move the grain from the silo to the malt mill, with dust extraction at every transfer point to limit dust explosion risk (ATEX). Temperature and moisture sensors in the silo detect heating or moisture ingress before quality loss occurs.

Brewing water and adjuncts

In addition to malt, many breweries use adjuncts (corn, rice, wheat) to manage cost or flavour profile. These raw materials require their own dosing and transport lines, separate from the malt line, to simplify product changeover and allergen management (for example, for gluten-free beers). Brewing water is pre-treated (softened, filtered) and stored in buffer tanks for consistent quality per brew.

FAQ — Brewing technology bulk handling

Why is malt grind size so decisive for brewing quality?

A grind that is too fine clogs the filter bed during wort clarification, extending brewing time. A grind that is too coarse fails to release enough starch, reducing extraction efficiency — and therefore yield. Consistent grind size requires a well-maintained malt mill with regular sieve-test checks.

How is cross-contamination between regular and gluten-free brews prevented?

Through separate storage and transport lines for gluten-containing grains and gluten-free adjuncts (such as corn grits), supplemented with validated cleaning procedures when lines must still be shared.

Read also

• Powder transport in closed systems 7-step guide
• What is the importance of CIP/SIP cleaning in powder processing systems
• What are the applications of a lock valve in powder processing
• Powder processing & transport: product overview

Our products

• Big bag filling station BG
• Feeding screw

Bulk Handling in the Paint and Coatings Industry

Paint manufacturers process a complex mix of raw materials: pigments, extenders, binders and solvents. Efficient bulk handling of these materials determines production capacity and product quality.

Key points

• Titanium dioxide (TiO2) and other pigments have a fine particle size (0.2-0.3 µm) and pose a significant dust explosion risk during transfer
• Binders and solvents require separate, ATEX-compliant storage and transfer lines, kept apart from solid raw materials
• Colour changeovers on the same line require thorough cleaning to prevent contamination with the previous batch
• Precise dosing of fillers and additives (often <1% of the formulation) determines the consistency of the final quality

Pigment handling

Titanium dioxide (TiO2) is the most widely used white pigment in paint. Big bag discharge with dust extraction and closed transfer to weighing hoppers is standard. TiO2 is not toxic but can cause respiratory irritation at high concentrations.

Dispersion process

Pigments and fillers must be dispersed in the binder solution. High-shear mixers break up agglomerates and disperse pigment particles to the desired fineness of grind. Hecht Technology supplies big bag discharge systems for paint production: hecht-technology.nl.

Fillers and additives

In addition to pigments, a paint formulation contains fillers (calcium carbonate, talc, kaolin) for volume and coverage, and additives (thickeners, preservatives, anti-foam agents) that often need to be precisely dosed in small quantities. Gravimetric dosing screws provide repeatable accuracy, even at dosing amounts of a few grams per batch.

FAQ — Paint and coatings bulk handling

Why does titanium dioxide pose a dust explosion risk?

TiO2 has a very small particle size and large specific surface area, which means it can form an ignitable dust-air mixture when dispersed into the air. Closed big bag discharge with dust extraction and ATEX-certified equipment limit this risk.

How do you prevent colour contamination during product changeover?

Through thorough cleaning of mixing installations and transport lines between colour changes, preferably in a fixed sequence (light to dark) to minimise residual product effects. Some manufacturers reserve separate lines for critical colours such as white or black.

Read also

• Powder transport in closed systems 7-step guide
• Pneumatic transport system in powder processing complete guide 2026
• How a lump crusher works in powder processing systems
• Powder dosing weighing process control guide

Our products

• Big bag filling station BG
• Feeding screw

Bulk Handling for Plastics Extrusion

Extrusion is one of the most widely used plastics processing methods for producing film, pipes, profiles and sheets. Efficient bulk handling of base polymers, colour concentrates and additives is essential for quality and profitability.

Key points

• PVC dry blend combines powder (PVC resin) with liquid and powder additives in precise ratios — deviations directly affect extrudate quality
• Masterbatch dosing (colour and functional concentrates) typically occurs at 1-5% of the base material and requires gravimetric accuracy
• Static charge in plastic granulate can cause caking in silos and transport lines
• Moisture content in hygroscopic polymers (PET, PA, PC) must be dried below a critical limit before extrusion to prevent hydrolysis

PVC dry blend production

PVC profile manufacturers produce their own dry blend by mixing PVC powder with stabilisers, lubricants and fillers in high-speed mixers. Cooling mixers cool the warm dry blend after mixing. Storage in silos, transport via pneumatic systems to the extruder hopper.

Additive dosing in extrusion

Colour concentrates, UV stabilisers and processing aids are dosed via gravimetric dosing devices. More info: hecht-technology.nl.

Granulate transport and static charge

Plastic granulate is generally transported pneumatically from silo to extruder hopper. Friction during transport builds up static charge, which can cause caking against pipe walls ("rat-holing") and bridging in the hopper. Grounded, antistatic transport lines and hoppers with proper angle construction limit this risk.

FAQ — Plastics extrusion bulk handling

Why must hygroscopic polymer be dried before extrusion?

Polymers such as PET, PA and PC absorb moisture from the air. When heated during extrusion, this moisture reacts with the polymer chains (hydrolysis), weakening the mechanical properties of the final product. Drying hoppers with dry air or vacuum dryers remove this moisture prior to processing.

How is masterbatch accurately dosed at low dosing percentages?

Gravimetric dosing screws with loss-in-weight control continuously measure the weight loss from the dosing hopper and adjust screw speed, enabling accuracies of up to ±0.5% — even at dosing percentages of just a few percent.

Read also

• Powder transport in closed systems 7-step guide
• What are the applications of a lock valve in powder processing
• What are the applications of a filling device in powder processing
• Powder dosing weighing process control guide

Our products

• Feeding screw
• Jett mill

Bulk Handling in Metal Surface Treatment

Surface treatment processes make intensive use of process chemicals. Safe and efficient bulk handling of acids, alkalis, solvents and powder coatings is essential for this industry.

Key points

• Pickling acids (hydrochloric acid, sulphuric acid) and alkalis require chemical-resistant storage with secondary containment against leakage
• Powder coating forms an explosive dust-air mixture when dispersed into the air — ATEX zoning is mandatory in coating rooms
• Colour changeover in powder coating requires complete cleaning of the booth and transport lines to prevent colour contamination
• Vapour and odour control at degreasing baths requires adequate extraction in accordance with occupational hygiene limit values

Powder coating: powder handling

Powder coating is supplied in bags or big bags. Big bag discharge into the coating room with dust control — powder coating forms an explosive dust-air mixture (ATEX zone). Colour changeover requires complete cleaning of the installation to prevent colour contamination.

Process chemicals handling

Pickling bath acids and degreasing baths are supplied in tanker trucks or IBCs. Secondary containment is mandatory for all hazardous liquids. More info: hecht-technology.nl.

Safe storage of process chemicals

Acids and alkalis for pickling and degreasing are delivered by tanker truck or IBC and stored in chemical-resistant tanks with drip trays or double-walled design as secondary containment. Separate storage of acids and bases — with sufficient distance or dividing walls — prevents dangerous reactions in the event of a leak.

FAQ — Metal surface treatment bulk handling

What ATEX measures apply to powder coating installations?

Powder coating booths generally fall under ATEX Zone 22 (dust, occasional). Grounded equipment, explosion-proof extraction and regular cleaning to limit dust accumulation are required. At high throughput, Zone 21 may apply, with stricter equipment certification requirements.

How do you prevent colour contamination during powder coating colour changeover?

Through complete booth cleaning (blowing, vacuuming, in some cases wet cleaning) between colour changes, and by processing light colours before dark colours in the production sequence to minimise residual powder effects.

Read also

• Powder transport in closed systems 7-step guide
• How a lump crusher works in powder processing systems
• What are the applications of a filling device in powder processing
• Powder processing & transport: product overview

Our products

• Big bag filling station BG
• Lifting equipment

Powder Technology: Bulk Handling of Fine Powders

Powder technology covers the production and processing of metal, ceramic and polymer powders for advanced applications. From AM powders for 3D metal printing to hard metal powders for cutting applications — each material calls for specific bulk handling.

Key points

• Particle size distribution (PSD), bulk density, flowability (Hausner ratio) and explosivity class together determine the design of a bulk handling installation
• AM powders for 3D metal printing require very narrow PSD specifications (typically 15-45 µm) and an inert atmosphere during handling
• Hard metal powders (tungsten carbide-cobalt) are abrasive and require wear-resistant lining in transport and dosing equipment
• Sub-micron powders after jet milling have extremely high cohesion and require special anti-bridging and anti-rat-holing techniques

Powder characterisation

Critical powder properties for bulk handling: particle size distribution (PSD), bulk density, flowability index (Hausner ratio), moisture content and explosivity class. These properties determine the design of the bulk handling installation.

Milling and classification

Jet mills, ball mills and attritor mills grind powders down to sub-micron particle size. Air classifiers classify at sharp cut sizes. Hecht Technology supplies containment solutions for fine powders: hecht-technology.nl.

Explosion safety for fine metal powders

Metal powders such as aluminium, titanium and magnesium have a low ignition energy and can cause severe dust explosions. Handling these powders requires inerting with nitrogen or argon, grounded equipment and ATEX category 1 versions for the most reactive materials. This is a fundamentally different risk class than organic or ceramic powders.

FAQ — Powder technology bulk handling

Why do AM powders for 3D printing require such a narrow particle size distribution?

A consistent layer thickness and melting behaviour during powder-bed fusion (SLM/DMLS) requires a narrow PSD without fine or coarse outliers. Distributions that are too broad lead to porosity and inconsistent density in the printed part. Classifying mills and sieving technology remove the unwanted fractions after primary production.

What additional measures apply to reactive metal powders such as aluminium and titanium?

In addition to standard ATEX measures (grounding, ignition-source-free), inerting with nitrogen or argon is common to fully exclude oxygen from transport and storage spaces. Moisture contact must also be avoided, since some reactive metal powders can generate hydrogen gas on contact with moisture.

Read also

• Powder transport in closed systems 7-step guide
• What are the benefits of a rotary valve in powder processing
• How a diverter works in powder processing systems
• Powder dosing weighing process control guide

Our products

• Jett mill
• Feeding screw

Bulk Handling of Welding Materials

The welding industry consumes large volumes of welding materials: welding wire, welding powder, flux and shielding gases. Efficient and safe storage and handling of these materials is essential for continuous, high-quality welding production.

Key points

• Welding flux for submerged arc welding (SAW) must stay dry (typically <0.05% moisture) — moisture causes porosity in the weld seam
• Welding wire in bulk drums (250-500 kg) reduces changeover frequency and machine downtime compared to small spools
• Recovery and reprocessing of unused welding flux (recycling) significantly lowers material costs in high-volume SAW welding
• Shielding gas cylinders and tanks require separate, ventilated storage kept apart from flammable materials

Welding flux handling

Submerged arc welding (SAW) uses fine welding flux as a flux medium. This powder is stored in dry silos or hoppers. Moisture is the biggest enemy of welding flux — damp flux leads to porosity in the weld. Drying in ovens at 300-400°C restores moisture uptake.

Welding wire logistics and storage

Welding wire is supplied on spools, reels or as bulk wire in drums. Bulk wire drums of 250-500 kg reduce the number of changeovers and increase production time. Dry storage in sealed spaces prevents rust formation. Hecht Technology supplies containment solutions for welding materials: hecht-technology.nl.

Shielding gas storage and distribution

Shielding gases such as argon, CO₂ and mixtures thereof are stored in cylinder banks or, for high consumption, in bulk tanks with distribution lines to the welding stations. Proper pressure control and leak detection prevent both gas waste and safety risks in confined spaces.

FAQ — Welding industry bulk handling

Why is moisture control so critical for welding flux?

Damp welding flux releases hydrogen during the welding process, which can cause hydrogen porosity and cracking in the weld seam — a critical quality defect in critical structures such as pressure vessels and pipelines. Dry silo storage and, if needed, re-drying at 300-400°C before use prevent this.

What are the benefits of bulk welding wire compared to spools?

Bulk wire drums of 250-500 kg require fewer changeovers than standard 15-20 kg spools, which increases productivity in automated welding (robotic welding) and reduces the risk of wire breaks during long weld seams.

Read also

• Powder transport in closed systems 7-step guide
• Which industries use powder transport systems
• How magnetic detection works in powder processing
• Powder dosing weighing process control guide

Our products

• Big bag filling station BG
• Lifting equipment

Industrial Powder Technology

Powder technology covers all processes for the production and processing of fine solids. From pharmaceutical APIs to metallurgical powders — each powder requires specific production, characterisation and processing technology.

Key points

• The production method (milling, precipitation, spray drying, atomisation) determines the morphology and processability of the final powder
• Compaction (pressing) forms loose powder particles into a green compact; sintering heats it below the melting point into a dense, cohesive product
• Pharmaceutical, ceramic and metallurgical applications each place different demands on purity, particle shape and compressibility
• Flowability (Carr index, Hausner ratio) determines whether a powder flows through hoppers and dosing equipment without bridging

Powder production methods

Powder is produced via milling (top-down), precipitation, spray drying, atomisation or chemical precipitation. Each method yields a specific particle size distribution, morphology and surface chemistry that determine processability and final product properties.

Characterisation of industrial powders

Critical characterisation parameters: PSD (laser diffraction), BET surface area, bulk density, tapped density and flowability (Carr index, Hausner ratio). Hecht Technology is a specialist in powder bulk handling: hecht-technology.nl.

Compaction and sintering

In powder metallurgy and technical ceramics, powder is first compacted (uniaxial or isostatic pressing) into a "green compact" with sufficient mechanical strength to handle, but still porous. Sintering then heats this green compact below the melting temperature, causing particles to bond together (diffusion) and the part to shrink into a dense, cohesive structure. The consistency of the powder characteristics before pressing — particle size, shape, flowability — directly determines the density and dimensional stability of the final product after sintering.

Applications by industry

In the pharmaceutical industry, powder characterisation directly determines the tabletability and dose uniformity of APIs. In technical ceramics, it determines the sintered density of final products such as insulators and cutting tools. In metallurgy (powder metallurgy, PM), precision characterisation makes it possible to produce near-net-shape parts with minimal post-processing.

FAQ — Industrial powder technology

What is the difference between compaction and sintering?

Compaction is the mechanical pressing of powder into a shape-stable green compact. Sintering is a thermal process in which this green compact is heated below the melting point, causing particles to bond through diffusion and the product to gain its final density and strength.

Which powder property is most decisive for compressibility?

Particle shape and size distribution are generally most decisive: irregularly shaped particles interlock mechanically and give higher green strength than spherical particles, which flow better but compress less well without a binder.

Read also

• Powder transport in closed systems 7-step guide
• How to prevent contamination in powder processing
• What are the benefits of powder processing
• Powder dosing weighing process control guide

Our products

• Jett mill
• Dosing gate

Industrial crystallisation process — definition: Complete end-to-end platform for scaled-up purification of pharmaceutical and chemical APIs via controlled crystallisation, including process development, scale-up validation, polymorph control, crystal characterisation and GMP batch manufacturing, in accordance with FDA 21 CFR Part 211, ICH Q6A and GMP Annex 1 (2022), with a focus on product quality, cost-effectiveness and process robustness.

Key points

• Crystallisation pipeline: method development (solvent screening, temperature profile) → pilot scale-up → process validation (3 batches) → production scale
• Standard: GMP Annex 1 (2022), FDA 21 CFR Part 211, ICH Q6A (product specs), ICH Q3C (solvent guideline), USP 921 (crystal growth)
• HECHT product: End-to-End Crystallization Platform + Multi-Scale Reactors + Integrated Analytics + GMP Documentation
• Application: pharmaceutical API purification, chemical specialties, polymorph selection, high-purity products
• Efficiency: 80–95% product recovery, >99% crystal purity, 50–80% cost saving vs. other purification methods

This complete guide describes crystallisation end-to-end: method screening, scale-up strategy, process validation and production optimisation. Test & Trial Centre in Pörnbach available for development support; see our integrated crystallisation platforms and API purification services.

FAQ — Industrial crystallisation process

How do you choose the best solvent for crystallisation development?

Screening: 10–20 solvents based on solubility-temperature profile (high at high T, low when cold). Preference: solvent with >2× solubility difference between room temperature and 0°C. GMP suitability: aim for ICH Q3C class 3 (low toxicity). Cost-effectiveness: recycling capacity >80%. Pilot screening: typically identifies 3–5 favoured solvents.

What are the main scale-up risks from 1L to 100L?

Risks: nucleation inhomogeneity (seed distribution), temperature gradients (large volumes), mixing ineffectiveness, contamination (handling). Mitigation: geometric similarity (height/diameter ratio), seed strategy (equal amount/volume), temperature profile verification (thermocouples). Validation: typically 3 consecutive batches at production scale.

How much time and cost for crystallisation process development to GMP?

Development: 2–4 months (method screening, 10–20 runs). Scale-up: 3–6 months (IQ/OQ/PQ, 3 validation batches). GMP dossier: 8–12 weeks. Total: 6–12 months. Cost: €100K–€300K (labour, analytics, small-scale apparatus). HECHT accelerates this via PAT and computational modelling.

How does cooling rate affect crystal size and purity?

Slow, controlled cooling produces larger, purer crystals because impurities have time to remain in the mother liquor rather than becoming trapped in the crystal lattice. Rapid cooling produces finer crystals with a larger specific surface area, which can complicate filtration but does increase yield per cycle. The right balance depends on the desired particle size for downstream processing such as filtration and drying.

Author: Joost van Velzen, Managing Director Hecht Technology B.V.

Related guides and solutions

• Vacuum drying: technology choice
• Powder processing in pharma (GMP)
• Industrial filter installations & dust separation
• Solutions for the chemical industry

Our products

• Columns and process towers
• Batch centrifuges

Bulk material handling determines the efficiency of virtually every powder processing operation. From unloading big bags to feeding reactors, every transfer is an opportunity for dust, product loss, segregation or downtime. A well-designed handling system is the difference between a smooth, safe production line and a chain full of bottlenecks. For engineers, buyers and QA in pharma, chemicals, food and the battery industry, HECHT delivers integrated bulk material handling that is dust-free, hygienic and reliable.

What does bulk material handling cover?

Bulk material handling is the entirety of systems that receive, store, transport, dose and discharge powders and granulates within a production process. It goes beyond individual machines: it is a chain in which every link must connect to the next.

A typical chain begins with the receipt of raw materials in bags, big bags or bulk trucks, and ends with feeding a mixer, reactor or packaging line. The challenge lies in the transfer points, where most problems arise.

The links in the handling chain

Each link has its own function and its own risks.

• Receipt and unloading — big bag discharge stations, sack tipping stations and discharge chutes with dust extraction
• Storage — silos, hoppers and IBCs with level monitoring and discharge promotion
• Transport — vacuum or mechanical transport between process steps
• Dosing — gravimetric or volumetric metering into the process
• Discharge and filling — containment filling heads into containers or packaging

Dust-free and closed design

Open transfer points are the largest source of dust and product loss in a handling chain. A closed design addresses this at every link, not just the most visible one.

• Closed discharge stations — big bags are emptied dust-free with sealed connections
• Extracted discharge points — displaced air is captured and filtered
• Closed transport — vacuum transport avoids exposure between process steps
• Containment discharge — filling heads close the chain dust-free

This protects operators, prevents cross-contamination and reduces raw material loss that hits margins directly.

Flow and preventing blockages

A handling system is only as reliable as its worst flow point. Powders with poor flow properties form bridges and ratholes in hoppers, leading to downtime. HECHT designs for guaranteed flow.

• Mass-flow hoppers — geometry that guarantees first-in-first-out flow
• Discharge promotion — vibrating bottoms, aeration or mechanical aids against bridging
• Segregation prevention — controlled discharge and transport to avoid separation of fractions

Hygiene, GMP and EHEDG

In pharma and food, hygiene is as critical as flow. Product residue in dead spots poses a contamination risk during product changeovers and complicates validation. HECHT supplies handling components with polished, crevice-free surfaces to GMP and EHEDG standards.

Cleaning via WIP or CIP enables thorough cleaning without disassembly, shortening downtime between batches and delivering reproducible results. This is essential for validated production.

Safety: ATEX and operator protection

Many bulk materials are combustible or highly active, so safety must be embedded in the design. For combustible powders the entire chain is earthed and built ATEX-compliant, with explosion protection where needed. For highly active substances, containment by OEB class provides operator protection, verified via SMEPAC.

An integrated approach prevents safety from becoming a patchwork of separate solutions: one system, one safety concept.

Frequently asked questions about bulk material handling

Where do most problems in a handling chain arise?

At the transfer points between links, where dust, segregation and blockages converge. An integrated design targets these points specifically.

How is bridging in hoppers prevented?

With mass-flow geometry and discharge promotion such as vibrating bottoms or aeration, matched to the flow properties of the product.

Is bulk material handling suitable for highly active substances?

Yes, with containment by OEB class and SMEPAC verification, the chain provides operator protection to high levels.

Can HECHT upgrade an existing line?

Yes, HECHT analyses your existing chain and replaces or integrates links to reduce dust, loss and downtime.

What does a closed handling chain deliver financially?

Lower raw material loss, less downtime, faster product changeovers and lower safety costs, reducing total cost of ownership.

Related guides

• Big bag handling
• Drum & barrel discharge
• Screw conveying
• Dosing guide
• Containment systems

Tailored advice from HECHT

Bulk material handling is not a sum of separate machines but a chain that must work as a whole. HECHT analyses your full process, identifies the bottlenecks and delivers an integrated system that is dust-free, hygienic and safe. Contact us for a process analysis and a handling concept tailored to your production.

Related guides and solutions

• Pneumatic powder transport
• Big bag handling
• Silo installations and bulk storage
• Dosing and weighing technology
• Containment: OEB 1 to 6

Our products

• BG big-bag filling station
• Lifting equipment

Pressure vessels are an indispensable part of many powder processing operations, particularly in pneumatic transport under positive pressure. A pressure vessel stores powder and then pushes it with compressed air through a pipeline to its destination. For engineers, buyers and QA in pharma, chemicals, food and the battery industry, pressure vessels are a reliable way to move powders over greater distances. At the same time, strict requirements apply to design, safety and certification. HECHT supplies pressure vessels that meet these requirements and integrate with your process.

What is a pressure vessel and how does it work?

A pressure vessel, also called a sender vessel or transmitter, is a closed reservoir that receives powder and discharges it under positive pressure. The operating principle is cyclical: the vessel is filled, sealed, pressurised with compressed air, and emptied as the powder is pushed through the transport line.

Unlike vacuum transport, which operates under negative pressure, a pressure vessel uses positive pressure. This makes it particularly suitable for long transport distances and high throughputs, because the available pressure is greater than under vacuum.

Applications of pressure vessels

Pressure vessels are used where distance, capacity or product properties call for positive-pressure transport.

• Long distances — transport over tens to hundreds of metres, where vacuum falls short
• High throughput — large quantities of powder per cycle, suitable for continuous production
• Dense phase transport — slow, product-friendly transport with minimal particle breakage
• Abrasive powders — controlled velocity limits pipe wear

In the battery industry and chemicals, pressure vessels are often used to move large volumes under inert conditions.

Dense phase versus dilute phase transport

A pressure vessel can convey powder through the line in two ways, with major consequences for product integrity and wear.

• Dilute phase — high air velocity, powder suspended in the air stream, suitable for free-flowing, non-friable products
• Dense phase — low air velocity, powder moves in plugs, product-friendly with minimal breakage, ideal for friable or abrasive powders

The choice determines the sizing of vessel, pipeline and compressed air supply. HECHT advises based on your product properties.

Safety and certification

A pressure vessel falls under the European Pressure Equipment Directive (PED, 2014/68/EU). This sets requirements for design, material selection, manufacture and inspection. An uncertified pressure vessel is a safety risk and not permitted in a professional installation.

• PED compliance — design and manufacture to the pressure equipment directive
• Overpressure protection — safety valves that prevent inadmissible pressure
• Material certification — traceable materials with certificates for process suitability
• Periodic inspection — re-inspection in accordance with applicable regulations

HECHT supplies pressure vessels with the required certification and documentation for your safety file.

Containment, hygiene and ATEX

Pressure vessels in pharma and food must meet hygiene and containment requirements alongside pressure ones. HECHT designs pressure vessels with polished, cleanable surfaces to GMP and EHEDG, with WIP or CIP where validated cleaning is required.

For combustible powders the pressure vessel is earthed and built ATEX-compliant. With reactive substances, as in the battery industry, nitrogen inerting can be applied to prevent explosion and unwanted reactions.

Sizing and process integration

The performance of a pressure vessel depends on correct matching of vessel volume, cycle time, pipe diameter and compressed air supply. An undersized system fails to achieve throughput; an oversized system wastes compressed air.

HECHT determines these parameters through product analysis and transport trials, and integrates the pressure vessel into the broader handling chain with dosing, filling and storage systems. The vessel thus functions not as a standalone component but as part of a coherent whole.

More about pressure vessels: in-depth articles

Want to read more about a specific topic? Below you will find all our articles on pressure vessels.

• How does a pressure vessel work?
• What are the main uses of pressure vessels?
• In which industries are pressure vessels used?
• How is the safety of pressure vessels ensured?
• What are the advantages of using pressure vessels?
• What materials are used to manufacture pressure vessels?
• How are pressure vessels maintained?
• What is the service life of a pressure vessel?
• Which regulations apply to pressure vessels?
• How is the pressure in a pressure vessel regulated?
• Why are pressure vessels important in chemical processing?
• Can pressure vessels be used to store gases?
• What is the role of pressure vessels in the food industry?
• How are pressure vessels cleaned?
• How is the correct size of a pressure vessel determined?
• What is the difference between a vertical and a horizontal pressure vessel?
• How do pressure vessels help to save energy?
• What is the function of a diaphragm in a pressure vessel?
• How are pressure vessels tested for leaks?
• What is the role of pressure vessels in the pharmaceutical industry?
• How are pressure vessels installed?
• How much does an industrial pressure vessel cost?

Frequently asked questions about pressure vessels

What is the difference between a pressure vessel and vacuum transport?

A pressure vessel operates under positive pressure and suits long distances and high throughput; vacuum transport operates under negative pressure and is inherently dust-safer in a leak.

When do I choose dense phase transport?

For friable or abrasive powders, where low velocity minimises particle breakage and pipe wear.

Must a pressure vessel be certified?

Yes, a pressure vessel falls under the PED directive and requires compliant design, manufacture and inspection.

Are pressure vessels suitable for pharma?

Yes, in GMP- and EHEDG-compliant versions with cleanable surfaces and optional WIP or CIP.

Can a pressure vessel operate under inert atmosphere?

Yes, with nitrogen inerting for reactive or combustible powders, relevant in chemicals and battery.

Related guides

• Vacuum technology
• Screw conveying
• Bulk material handling

Tailored advice from HECHT

A pressure vessel that fits your process requires correct sizing, the right transport phase and complete certification. HECHT analyses your distance, throughput and product properties and delivers a PED-compliant pressure vessel that is safe, hygienic and integrated into your handling chain. Contact us for a transport analysis and a tailored pressure vessel concept.

Our products

• Pressure vessels and storage tanks

A homogeneous end product is, in many industries, not a luxury but a requirement. Whether it concerns a pharmaceutical formulation, a food product, a coating or a battery slurry, the consistency of the mix composition determines the quality. Homogenisers ensure that components are evenly distributed down to micro or nano scale. For engineers, buyers and QA in pharma, chemicals, food and the battery industry, HECHT delivers homogenisation solutions that are reproducible, hygienic and safe.

What does a homogeniser do?

A homogeniser reduces and distributes particles or droplets in a medium so that a uniform, stable composition results. The device applies intensive mechanical forces — shear, pressure, impact and cavitation — to break agglomerates and mix phases evenly.

The aim is a product in which no measurable differences in composition exist between different samples. This is essential for both product quality and process reproducibility.

Operating principles of homogenisation

Homogenisers work according to various physical principles, each suited to different applications.

• Shear — high velocity differences between rotor and stator break particles and droplets apart
• High pressure — the medium is forced through a narrow gap, where pressure and cavitation reduce particle size
• Impact — particles collide with surfaces or each other, breaking up agglomerates
• Cavitation — imploding vapour bubbles deliver locally intense energy for particle reduction

The combination of these forces determines the fineness and uniformity of the end result.

Types of homogenisers

Various constructions exist, matched to product and desired result.

• Rotor-stator homogenisers — a fast-rotating rotor in a fixed stator, versatile for mixing and dispersing
• High-pressure homogenisers — for very fine emulsions and suspensions down to nano scale
• Inline homogenisers — integrated into a continuous process flow, suitable for high throughput
• Batch homogenisers — for processing metered quantities in a vessel

HECHT advises the type that fits your viscosity, particle-size requirement and production format.

Applications by industry

Homogenisation is broadly applicable, each time with different goals.

• Pharma — uniform distribution of APIs in suspensions and emulsions, critical for dosing and efficacy
• Food — stable emulsions and consistent texture in sauces, dairy and beverages
• Chemicals — dispersion of pigments and additives into stable coatings and pastes
• Battery — homogeneous electrode slurries, decisive for cell performance and lifetime

In the battery industry, homogenisation of slurries is a direct quality factor: inhomogeneity leads to local capacity differences and shorter lifetime.

Hygiene, GMP and cleanability

In pharma and food, a homogeniser must deliver hygiene alongside performance. Product residue in dead spots poses a contamination risk and complicates validation. HECHT supplies homogenisers with polished, crevice-free surfaces to GMP and EHEDG.

Cleaning via WIP or CIP enables validated cleaning without disassembly, shortening downtime between batches and delivering reproducible results. For validated production this is a hard requirement.

Safety: ATEX and containment

Many homogenisation processes handle combustible solvents or powders, or highly active substances. Safety must therefore be embedded in the design. For combustible media the homogeniser is earthed and built ATEX-compliant, with inerting where needed.

For highly active substances, homogenisation is integrated into a closed, containment-compliant system, verified to SMEPAC. Operator protection thus remains assured, even under intensive mechanical processing of the medium.

Frequently asked questions about homogenisers

What is the difference between mixing and homogenising?

Mixing distributes components coarsely; homogenising reduces particles and droplets to a uniform, stable composition at micro or nano scale.

Which type of homogeniser fits my product?

That depends on viscosity, desired particle size and whether you produce in batch or continuously; HECHT advises based on your product properties.

Is homogenisation suitable for battery slurries?

Yes, homogeneous electrode slurries are crucial for cell performance; HECHT delivers solutions tailored to this application.

Can a homogeniser be cleaned in a validated way?

Yes, with GMP- and EHEDG-compliant construction and WIP or CIP for cleaning without disassembly.

Are homogenisers available ATEX-compliant?

Yes, in earthed, zone-certified versions with optional inerting for combustible media.

Related guides

• Powder processing
• Pharma powder processing
• Industrial filtration

Tailored advice from HECHT

The right homogeniser depends on your product, particle-size requirement, production format and safety and hygiene requirements. HECHT analyses your process and delivers a homogenisation solution that is reproducible, hygienic and safe, integrated into your handling chain. Contact us for a process analysis and a tailored homogeniser concept.

Our products

• Jett mill

See also: cleaning and maintaining homogenisers

Industrial filtration separates solid particles from gas or air streams and is indispensable in every form of powder processing. For manufacturers in pharma, chemical, food and the battery industry, the filtration strategy determines whether a process runs dust-free, safe and GMP-compliant. HECHT designs filtration solutions that combine operator protection, product retention and process efficiency. This page explains the available techniques, how to select a filter, and what to consider regarding OEB bands, ATEX and hygienic design.

Why filtration is critical in powder processing

Every transfer, conveying step or dosing operation releases fine dust. That dust poses three risks at once: operator exposure, cross-contamination of product and explosion hazard with combustible powders. Effective filtration captures particles before they spread, keeps the working environment clean and protects downstream equipment from wear.

Correct filtration also lowers your OPEX. Less dust loss means higher yield, less cleaning and longer service life for pumps and fans.

Key filtration techniques

The choice depends on particle size, flow rate, dust load and the required separation efficiency.

• Cartridge filters — compact, high filter area per volume, ideal for fine dust and continuous operation
• Bag filters — robust at high dust loads and coarser particles, easy to maintain
• HEPA/ULPA filters — for critical separation up to 99.995%, essential in pharma and cleanrooms
• Cyclones — pre-separation of the coarse fraction, reducing the load on the main filter
• Sintered lamellas and metal filters — for high temperatures, aggressive media and cleanable applications

Cleaning: jet-pulse and mechanical

A filter inevitably becomes saturated. Cleaning during operation determines continuity. Jet-pulse cleaning uses a short blast of compressed air to release the filter cake from the medium, so the process need not stop. For containment applications, bag-in-bag-out (BIBO) designs let you replace the filter without exposure. Differential pressure monitoring tracks saturation and signals the right moment to clean or replace.

Filtration and OEB bands

For active pharmaceutical ingredients (APIs), the OEB band is decisive. The higher the OEB band, the lower the permitted exposure and the stricter the requirements for filtration and containment.

• OEB 1–2 — standard dust extraction with cartridge or bag filter often suffices
• OEB 3–4 — closed systems with HEPA final filtration and safe filter replacement
• OEB 5 — isolator technology, dual HEPA filtration and validated BIBO procedures

ATEX and explosion safety

Many powders are combustible. As soon as a dust-air mixture is ignitable, the installation falls under the ATEX directive. Filtration systems must then be designed with explosion-pressure-resistant housings, pressure relief, spark detection or an ignition-source-free design. HECHT supplies ATEX-compliant filter units with the correct zoning and documentation.

Hygienic design: GMP and EHEDG

In pharma and food, cleanability matters as much as separation. Filtration components built to GMP and EHEDG guidelines have smooth surfaces, no dead zones and are CIP/WIP-cleanable. Stainless steel 316L, FDA-compliant seals and validated cleaning procedures prevent cross-contamination between batches.

Filter selection in practice

Good selection starts with process data: which powder, which particle size distribution, which flow rate and which separation efficiency. From there you define the filter class, the cleaning principle and the containment requirements. HECHT calculates the filter area based on the permitted filtration velocity, so you neither over- nor under-dimension.

Frequently asked questions about industrial filtration

Which filter class do I need for pharmaceutical powder?

For APIs with a high OEB band, HEPA H13/H14 is the starting point, often combined with a pre-filter and validated BIBO replacement.

What is the difference between a cartridge and a bag filter?

Cartridge filters offer more area in less space and perform better with fine dust. Bag filters are more robust at high dust loads and coarser particles.

How often must I replace filters?

That depends on dust load and cleaning principle. With jet-pulse cleaning filters last longer; differential pressure measurement indicates the right replacement moment.

Is my process subject to ATEX?

As soon as a combustible dust-air mixture can form, ATEX applies. A dust explosion analysis determines the zoning and the required protection.

Can I combine filtration with existing equipment?

Yes. HECHT integrates filtration into existing conveying, dosing and filling lines, including the correct containment connections.

Related guides

• ATEX & explosion safety
• OEB bands
• Industrial vacuum cleaners
• Containment systems
• Powder processing

Tailored advice from HECHT

Want to know which filtration solution suits your powder, OEB band and process? HECHT's specialists analyse your situation and design a system that protects operators, retains product and complies with GMP and ATEX. Contact us for a no-obligation consultation.

Our products

• Nutsche filter dryers