CIP Systems Explained: Automating Cleaning in Food Production

This guide explains how CIP systems automate cleaning across food, dairy, beverage and brewing plants without dismantling production equipment. It covers the main clean-in-place cycle stages, including pre-rinse, caustic washing, intermediate rinsing, acid cleaning, final rinsing and optional sanitisation. The article also explains the TACT principles of time, action, chemical concentration and temperature, along with the core components of a CIP skid, such as tanks, pumps, heat exchangers, dosing equipment, instrumentation and valve matrices. It compares single-use, reuse and multi-tank systems, outlines key specification considerations and highlights what buyers should inspect when purchasing a used CIP system.

Josh Bray

Sep 17, 2026

Every dairy, brewery and beverage plant faces the same daily problem. Product leaves residue on tank walls, inside pipework, across plate packs and around valve seats, and none of it can stay there. Strip the plant down by hand and you lose hours, damage seals and gaskets, and expose operators to hot caustic. Circulate cleaning solution through the closed plant instead, and you clean faster and more safely.

That is the job a CIP system does. This guide explains how clean in place works, what each stage of the cycle achieves, how the hardware is built, and what to inspect before you buy a used skid.

What Clean in Place Actually Means

'Clean in place' describes cleaning the wetted interior of tanks, pipework, pumps, valves, fillers and heat exchangers without dismantling any of them. The plant stays assembled and closed. A CIP system pumps water and cleaning solutions through the same route the product takes, at controlled temperature, concentration and flow, then returns the spent solution to the skid for recovery or drain. Inside vessels the solution reaches surfaces through spray balls or rotary jet heads. Inside pipework and heat exchangers, it scours the surface directly as it flows.

Why automated cleaning beats stripping the plant by hand

Repeatability comes first. CIP systems run the same recipe every time, so the clean does not vary with who is on shift or how late the changeover is running. Manual cleaning depends on effort and attention, and both fluctuate.

Evidence comes second. Because the skid logs temperature, conductivity, flow and cycle duration, you can show an auditor or a customer exactly what happened during each clean rather than describing your intentions.

Safety and plant life matter just as much. Hot caustic belongs inside closed pipework, not in an open bucket beside an operator with a scouring pad. Repeated dismantling also wears out gaskets, clamps and valve seats. Add the downtime saving at scale, and a clean-in-place system usually pays back on labour alone.

The Classic CIP Cycle Step by Step

Most liquid food plants run a recognisable sequence. Your soil, product and chemical supplier guidance should set the exact times, temperatures and concentrations, but the order rarely changes.

Pre-rinse with water to push out gross soil so you do not waste detergent dissolving material a rinse could have removed.
Caustic detergent wash, typically an alkaline solution in the region of 1 to 2 per cent, circulated warm to hot to break down fats, proteins and general organic soil.
Intermediate rinse to flush caustic and loosened soil out of the circuit before the next chemical goes in.
Acid wash, often a nitric or phosphoric-based solution at lower concentration, to strip mineral scale, milkstone, beerstone and bound protein deposits that alkali leaves behind.
Final rinse with treated water of a quality suitable for the product, removing all chemical traces.
Optional sanitisation using a chemical sanitiser or hot water, applied when the gap between cleaning and production requires it.

Not every circuit needs every step. Beverage lines with light sugar soil often run acid weekly rather than daily, while dairy pasteurisers with heavy protein and scale need both chemicals every time. Validate whichever sequence you choose against your own soil and HACCP plan.

The Four Levers That Make CIP Cleaning Work

Cleaning performance rests on four factors, widely remembered as TACT.

Time: how long the solution stays in contact with the soil.
Action: mechanical energy, delivered as flow velocity in pipework or spray impact inside vessels.
Chemical: the type and concentration of detergent or acid.
Temperature: the heat of the circulating solution, commonly warm for beverage soils and hotter for fatty dairy soils.

The four trade against each other. Drop the temperature, and you need longer contact time or a stronger chemical. Cut concentration to save money, and the cycle must run longer or hotter. Weak flow velocity cannot be rescued by any amount of caustic, because the soil never gets the scrubbing it needs. Good CIP cleaning balances all four, and your chemical supplier should help set working ranges for your soil.

Inside a CIP Skid

The hardware is straightforward once you see it laid out.

Tanks: a balance or recovery tank, plus dedicated detergent and acid tanks on larger units and a fresh water tank where rinse recovery is used.
Pumps: a supply pump sized for the required flow velocity and a return pump that pulls solution back from the furthest point of the circuit.
Heating: usually a plate heat exchanger fed by steam or hot water, bringing solution to the set point quickly.
Dosing: chemical pumps drawing from bulk containers, controlled against a live concentration reading.
Instrumentation: conductivity for concentration and phase change, temperature probes, flow meters, level sensors and pressure transmitters.
Distribution: spray balls or rotary jet heads inside vessels and a valve matrix that routes each circuit without cross-contamination.

The valve matrix deserves attention on any CIP system you inspect. It keeps caustic out of a product line during production and product out of the drain during cleaning, and rebuilding a neglected one is expensive.

Why turbulent flow matters more than pressure

Operators often ask for more pressure when a clean falls short. Pipework does not work that way. What removes soil from a pipe wall is turbulent flow, and turbulence depends on velocity. Most liquid food plants design for roughly 1.5 to 2.1 metres per second through product pipework, then verify it with a flow meter.

Design faults are the usual reason a cycle fails validation. Dead legs where solution stalls, lines that do not fall towards a drain point, threaded fittings and valves not intended for hygienic service all create pockets the solution never scours. Fixing the pipework beats extending the cycle.

Single-Use, Reuse and Multi-Tank Configurations

How you handle spent solution shapes water use, chemical cost, footprint and capital outlay. The three common layouts compare like this.

``` ```

Factor	Single-use	Reuse (recovery)	Multi-tank
Water consumption	Highest, all solution drains away.	Moderate rinse water recovered	Lowest, rinse and chemicals recovered
Chemical consumption	Highest, fresh dose each cycle	Moderate, caustic, reused	Lowest, caustic and acid held and topped up
Capital cost	Lowest, simplest build	Middle	Highest, more tanks, valves and control
Footprint	Compact, suits tight plant rooms	Moderate	Largest, needs dedicated floor space
Best suited to	Heavy or variable soil, allergen changeovers	Consistent soil, medium-volume dairy and beverage	High-volume dairy, brewing and continuous plants
Final rinse recovery	None, rinse drains away.	Often reused as the next pre-rinse	Recovered into a dedicated tank
Cycle time	Shorter cycle, longer refill and reheat	Balanced, solution already hot	Fastest, hot solution on demand
Indicative used price	£4,000 to £15,000	£12,000 to £40,000	£30,000 to £120,000 and above

Capacity, age, instrumentation and control platform move those figures, so treat the final row as a guide.

Specifying a CIP System for Your Plant

Start with circuits. Count how many separate cleaning routes you have, how long each one is, and whether any need to run at the same time. That count drives the valve matrix, the pump duty and the tank volumes more than anything else.

Then work through the constraints. Tank volumes must hold enough solution to fill the largest circuit and keep the return flooded. Chemical recovery decides your annual detergent spend. Effluent handling matters because caustic and acid cannot simply go to the drain, so you need pH neutralisation and a discharge consent that fits your site. Water treatment quality affects the final rinse and the scale you pay to remove later.

Control integration is the last piece. A modern CIP system should hand recipes, step states, alarms and cycle records to the plant PLC, so cleaning appears in production records rather than in a separate notebook.

Buying a Used CIP System

Used skids sell well because tanks and frames last for decades while controls date quickly. Focus your inspection accordingly.

Tanks and frame: check for pitting, weld corrosion, insulation damage and any improvised repair.
Pumps and seals: listen for cavitation, check mechanical seals and confirm impeller sizing matches your flow.
Heat exchanger: look for fouling, plate distortion and gasket condition, and ask when the pack was last opened.
Valves and actuators: cycle every valve, check seat and seal condition and confirm feedback switches respond.
Instrumentation: ask whether conductivity, temperature and flow probes are included and when they were calibrated.
Controls: establish the PLC and HMI age, whether the platform is still supported, and whether you can edit the program.
Paperwork: request manuals, wiring drawings and P&IDs, and confirm CE or UKCA marking.

Assume a used skid needs recommissioning. Budget for seals, gaskets and probe calibration, often a controls refresh, then plan a fresh cleaning validation on your own soil before the CIP system touches production. That work is predictable, and it still costs far less than buying new.

Find Cleaning and Sanitation Equipment on Machinery Masters

Machinery Masters is a UK B2B marketplace for new and used industrial equipment, with listings from verified sellers across food, beverage and process industries. Buyers pay no commission, and financing is available to qualified applicants. Browse the cleaning and sanitation category to see which CIP systems, tanks and washing equipment are currently listed, or list your own surplus equipment if you have assets standing idle after a line change.

Frequently Asked Questions

What does CIP stand for in food production?

CIP stands for clean in place. It describes cleaning the interior surfaces of tanks, pipework, pumps, valves and heat exchangers by circulating water and cleaning solutions through the closed plant, without dismantling equipment. The method suits dairy, brewing, beverage and liquid food production lines.

How long does a CIP cycle take?

Cycle time depends on circuit length, soil type and the chemicals used. Many liquid food circuits run between thirty and ninety minutes for a full sequence, and lighter beverage circuits finish faster. Validate your own timings against your soil, chemical supplier guidance and HACCP plan.

Why does flow velocity matter more than pressure?

Soil comes off a pipe wall through turbulent flow, not through pressure. Turbulence depends on velocity, so most plants design for roughly 1.5 to 2.1 metres per second in product pipework and verify it with a flow meter. Raising pump pressure without achieving velocity rarely improves CIP cleaning.

Is a used CIP system worth buying?

Often yes. Tanks, frames and heat exchangers last for decades, so value sits in condition rather than age. Check pumps, seals, valves, probe calibration and whether the PLC platform remains supported and programmable. Budget for recommissioning and a fresh cleaning validation before production use.

What is a CIP skid?

A CIP skid is a self-contained, frame-mounted unit holding the tanks, pumps, heater, dosing pumps, instrumentation and controls that run cleaning cycles. It connects to plant circuits through a valve manifold, supplying cleaning solution and receiving the return flow for recovery or drain.

Can a one-cleaning-in-place system serve a whole plant?

Often yes, provided the skid has enough circuits, tank volume and pump duty for your longest route. Larger sites sometimes split duties between a central CIP system and smaller local skids to shorten pipe runs, cut solution volumes and allow cleaning during production elsewhere.