Editorial Technical Reference

Reagent feed system (metering pump skid) for continuous chemical reactors

Reagent delivery to continuous reactors · Pump type against pressure and solids, metering range and stroke control, wetted materials

A reagent feed system, as used on this page, is the skid of tanks, metering pumps, pulsation control, flow measurement and valves that delivers each feed stream into a continuous reactor at a set rate and pressure. It is specified separately from the reactor because its pump choice is set by what is being fed — a clear solution, a suspension or a slurry — and by the reactor's pressure. Ask three things first: what solids content and particle size each feed carries, what pressure the reactor runs at, and how precisely and steadily each stream must be metered.

Feed and metering skids for continuous chemical and pharmaceutical reactors: metering pumps (piston, syringe, peristaltic, diaphragm), feed tanks, flow measurement, pulsation dampeners and control valves. The reactors themselves — plug-flow, microchannel and tubular reactors for drug substance synthesis — are covered on the Continuous flow reactor for pharmaceutical synthesis page. Antenna feed systems, animal feed equipment and batch charging of stirred reactors are outside this page.

CNFX editorial research · Sources checked October 12, 2026 · 3 sources

Match pump to feed Size the metering range

Stainless steel feed skid with two yellow diaphragm metering pumps, two flow transmitters and valved pipework under a conical hopper, beside a stainless process vessel where a technician in gloves operates a valve — Metering pump feed skid beside a process vessel

Start with your task

Match pump to feedSolids, pressure, pulsation. Size the metering rangeFlow, pressure, materials.

Match the pump type to what you are feeding and the reactor pressure

A 2026 review in Communications Chemistry (Johnston and co-authors) on solids handling in continuous flow synthesis states that piston and syringe pumps deliver homogeneous liquids accurately at pressures exceeding 100 bar, but their narrow fluid paths block with solids and particles settle in the barrel or chamber, so they are restricted to dissolved solutions or suspensions with negligible solids. [1]

Peristaltic pumps handle slurries and suspensions in fluoropolymer tubing such as PTFE or FEP, provided particles are no more than one-third of the tubing diameter and stay dispersed; the review puts their pressure tolerance below 10 bar and notes their pulsatile flow. Diaphragm pumps handle suspensions of 1–20% solids by volume and slurries of 20–60% solids. Solenoid-driven diaphragm pumps dose 0.36–80 L/h at up to 25 bar with ±1% reproducibility, while air-operated double-diaphragm pumps move 1–1,040 L/min at up to 8.6 bar with solids up to 10 mm. Both suffer pulsating flow, mitigated by pulsation dampers or multiple diaphragms, and diaphragm wear. [1]

Editorial calculation: with 1.6 mm bore tubing, the one-third rule limits particles to about 1.6 ÷ 3 ≈ 0.53 mm. [1] Editorial note: if a reactor runs above 10 bar, the review's figures rule out peristaltic feed for that stream; ask how pulsation will be damped before the reactor inlet.

Give the supplier each feed stream's composition, solids content and particle size, viscosity, density, temperature, required flow range and turndown, reactor inlet pressure, allowed pulsation, metering accuracy, wetted materials needed, hazardous-area classification, and whether the skid must be cleaned or flushed between campaigns.

Size the metering range, pressure and wetted materials

ProMinent lists its motor-driven metering pumps by capacity and pressure: the alpha at 1.0–30.6 L/h and 10–2 bar, the Sigma/1 at 17–144 L/h and 12–4 bar, the Sigma/2 at 50–420 L/h and 16–4 bar, and the Sigma/3 at 146–1,030 L/h and 12–4 bar. Metering rate is set by stroke length and stroke rate, and ProMinent states the metering volume can be adjusted in 1% steps. [3]

LEWA's ecoflow diaphragm metering pumps are built to API 675 and reach flow rates up to 19 m³/h per pump head or discharge pressures up to 1,200 bar, with suction down to 0.1 bar absolute. Its M500 pump head, with a PTFE sandwich diaphragm and diaphragm position control, is listed at 350 bar, 19 m³/h, −50 to +150 °C and viscosities to 100,000 mPa·s, in 1.4401/1.4404 (AISI 316/316L) stainless steel, PVC or PVDF; flow is adjusted by electric or pneumatic stroke adjustment or by variable-frequency motor drive. [2]

Editorial calculation: ProMinent's Sigma/3 maximum of 1,030 L/h equals 1.03 m³/h, against LEWA's 19 m³/h per head, so a production feed can need a larger pump class or two or more heads per stream. [3] [2]

Compare feed pump types

Pump type	Handles	Limits from the sources
Piston or syringe pump	Homogeneous liquids. [1]	Pressures above 100 bar; blocked by solids.
Peristaltic pump	Slurries in PTFE or FEP tubing. [1]	Below 10 bar; particles ≤ ⅓ tubing bore; pulsation.
Solenoid diaphragm pump	Suspensions at low flow. [1]	0.36–80 L/h, 25 bar, ±1%.
Air-operated double-diaphragm pump	Viscous slurries, solids to 10 mm. [1]	1–1,040 L/min, 8.6 bar.
Motor-driven diaphragm metering pump	Liquids at process scale. [3] [2]	Up to 1,030 L/h (Sigma/3) or 19 m³/h per head (ecoflow).

Reagent tank, metering pump, pulsation dampener, flow meter, check valves and stroke control

Part	Role	Fix in the order
Feed reservoir or tank	Holds each reagent; may need agitation to keep solids dispersed. [1]	Volume, agitation, inerting.
Feed pump	Meters the stream at reactor pressure. [1]	Type, flow range, pressure.
Pulsation dampener	Smooths diaphragm or peristaltic pulsation. [1]	Type and size.
Flow meter	Confirms delivered rate.	Principle, range, accuracy.
Control valve and check valves	Isolate, prevent backflow, hold pressure.	Valve type and materials.
Control unit	Sets stroke length, stroke rate or speed. [3] [2]	Signal type; interface to the reactor control system.

Feed rate, discharge pressure, accuracy and wetted materials for each reagent stream

Fill one row set per reagent: solids content decides the pump type, since piston and syringe pumps block on particles while peristaltic pumps stay below 10 bar. [1]

Field	What it means and published values	Ask the supplier for
Feed Rate (m³/h)	0.0010–1.03 m³/h across ProMinent alpha to Sigma/3; up to 19 m³/h per ecoflow head (editorial conversion of L/h). [3] [2]	Minimum and maximum rate per stream.
Feed Accuracy (%)	±1% reproducibility for solenoid diaphragm pumps in the review. [1]	Steady-state accuracy and how it is tested.
Operating Pressure (MPa)	Peristaltic < 1 MPa (10 bar); piston > 10 MPa (100 bar); M500 head 35 MPa (350 bar). Editorial unit conversion. [1] [2]	Rated discharge pressure at your reactor inlet.
Operating Temperature (°C)	−50 to +150 °C for the LEWA M500 head. [2]	Fluid temperature range.
Power Supply (V DC)	Drive and control supply.	Voltage for pumps and controls.
Power Consumption (kW)	Sum of pump drives and heating or agitation.	Installed power.
Ingress Protection	Pump motors and instruments.	IP rating; hazardous-area rating.
Material of Wetted Parts	316/316L, PVC or PVDF heads (LEWA); PTFE or FEP tubing (peristaltic). [2] [1]	Materials for each reagent.
Connection Size	Suction and discharge connections.	Size and standard.
Weight (kg)	Skid weight for installation.	Weight with tanks empty and full.

Send the stream, pressure and material data together

Paste it into your enquiry below or into an email to a maker, then replace every bracket.

Streams: [reagent; solids %; particle size; viscosity]
Rates: [min and max per stream; accuracy]
Pressure: [reactor inlet; allowed pulsation]
Materials: [wetted materials; seals]
Control: [signal; interface to reactor control]
Site: [hazardous area; cleaning between campaigns]

See manufacturer records Send an enquiry through CNFX

Buyer questions

Which pump suits a slurry feed?

The Communications Chemistry review lists peristaltic pumps below 10 bar with particles up to a third of the tubing bore, and diaphragm pumps for 1–20% suspensions and 20–60% slurries. [1]

How high can a feed pump's pressure go?

The review puts piston and syringe pumps above 100 bar; LEWA lists its ecoflow series up to 1,200 bar. [1] [2]

How is a metering pump's rate adjusted?

By stroke length and stroke rate or motor speed; ProMinent states 1% adjustment steps. [3]

Sources and what still needs a direct check

Sources checked 2026-10-12. The Communications Chemistry review is a peer-reviewed survey of solids handling in flow synthesis; LEWA and ProMinent are metering pump makers describing their own ranges.

Johnston et al., Advances in solid handling for continuous flow synthesis of specialty chemicals and pharmaceuticals, Communications Chemistry (2026) ↗ Peer-reviewed review Return to text ↑
LEWA — ecoflow diaphragm metering pump ↗ Maker product page Return to text ↑
ProMinent — Motor-driven metering pumps ↗ Maker product page Return to text ↑

Still to check yourself

Characterise solids and particle size per stream.
Match pump type to reactor pressure.
Fix flow range, accuracy and pulsation limits.
Choose wetted materials for each reagent.
Verify the legal supplier and factory.