4da2c21238509 Cleaning in Place Systems Design Manual

Lowfields Road Leeds, LS12 6BS, UK Tel: Tel: +44 (0) (0) 113 113 244 5225 Fax: +44 (0) 113 244 5226 [email protected] www.microdat.co.uk

Cleani Cleaning ng In Place (CIP (CIP)) System Desig Desig n Manu Manual al A cleaning cleaning In Place P lace (CIP (C IP ) system is designed designed to to clean a liquid processing processing plant without without the need to strip it down into component parts, and manually clean with scourers etc. The The ben benefit efit of a CIP syst system em, is that once once set set-up, -up, it will ill clea clean n the plan plantt equ equipm ipment ent, time and and agai again, n, while the operators get on with other duties, i.e. it is supposed to be labour saving. It is possible possible to have a very simple simple manual CIP CI P system, but here there is little benefit of labour saving. A CIP C IP system has has to be designed properly to match match the the plant being cleaned. The The prim primary ary fun functio ction n is soil soil removal oval,, bu but also also to san sanitis itise e the proc proces ess s equi equip pment ent. This This docum ocument ent is desi design gned ed as an out outlin line guide ide for corr correc ectt CIP syst system em desig esign n and and sele select ctio ion n.

A Microd Microdat at Pharm P harmaceut aceutical ical Grade G rade Single Shot Total Loss Automatic CIP System

Microdat Microda t is a trading name of Microdat.co.uk Microdat.c o.uk Limited. Microdat.co.uk Microda t.co.uk Limited is a company registered in England and Wales Wale s with company number 4299819. Registered Re gistered Office: Offi ce: Microdat.co.uk Microdat. co.uk Limited, Lowfields Road, R oad, Leeds, Lee ds, LS 12 6BS. BS . Telephone Tel ephone +44 (0) 113 244 5225, Fax: +44 (0) 113 244 5226. Website: Webs ite: www.microdat.co.uk , E mail: [email protected] [email protected] .uk , VAT Number: 780 5449 11.

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1

SOIL REMOVAL

For effective cleaning we need to consider : Temperat eratu ure +Scouri +Scourin ng Act Action ion +Time +Time +Det +Deterge ergen nt Typ Type & Conce Concent ntrratio ation n If any of these aspects are not sufficient, then cleaning will be compromised. 1.1

TEMPERATURE

Most detergents become more effective when hot, and in a dairy, where the soiling is fat based, temperature temperature is very important important.. Use Use of hot (80 C) CIP will also effectively pasteurise the plant, killing off any possibility of infections. °

However, given the the additional energy requirem requirements, ents, Hot CIP C IP has largely been replaced in small breweries, with the use of cold detergents and chemical terminal sanitisers in the final rinse, except for the brewhouse, where hot CIP assists in the removal of sugars. 1.2

SCOURING ACTION - PIPES

A scouring action is required to assist the detergent to remove the soiling in pipework systems. When fluid passes down a pipe, contact with with the tube tube internal wall wall creates friction. At low velocity this this friction has little little effect, and the flow is sm smooth and laminar. laminar. However, at higher velocity, the flow becomes very turbulent, and this turbulence creates an internal scouring action. 1.3

SCOURING ACTION - TANKS

In tank cleaning, scouring action can be provided by a modern CIP tank cleaning head. Thes These e devic evices es crea creatte jet jets of of fluid, like a high-pressure hose, cutting into and removing soiling.

1"OD

2"OD

9600kg/hr

Vent

1"OD

LIGHT

STEELES MASHER SA3353

D O " 2

3200 Kg MASHTUN SA3354

With a cleaning head, there is some reliance on a soaking action, and also more reliance on the action of the detergent.

WORM& GEAR

P107

More detail about cleaning heads is provided the CIP system design section.

GRAIN DISCHARGE

2"OD D O " 2

SP

Tank Tan k Cle Clean anin ing g Ap App pli lica cattio ion n In A Brew Brewho hou use





1.4

TIME CONSIDERATIONS

The The minim inimum time for a CIP cycl cycle e is depen epend dent ent upon upon all all the oth other fact actors; ors; corr correc ectt scou scourring ing action, detergent type & concentration, and temperature. If one part of the equation is not ideal, then extending the time can sometimes compensate. Too lit little time, and and the soil soilin ing g will ill not be removed oved,, but but there ere is lit little benef enefit it in massi assiv vely ely over over extending cycle times. 1.5

DETERGENT TYPES & CONCENTRATIONS

The The cor correct rect choi choice ce of deter eterg gent ents con conttribu ributtes str strong ongly to the eff effect ectiven ivenes ess s of of CIP. The The stan standa darrd in smal smalll to mediu edium m brew brewer erie ies s is is Caus Causttic Soda Soda (Sodi (Sodiu um Hyd Hydroxid oxide) e),, which hich is cheap and readily available. CIP detergents detergents also also contain additional additional active components, components, referred to as sequestrants, and surfactants, which are designed to keep soiling in suspension once removed from the surfaces, and to reduce foaming and to give other beneficial properties. Other chemicals are sometimes added by the supplier, to create specific cocktails providing benefits to plant problems, such as beer-stone removal. In some brewery applications, with high CO2 atmospheres, an acid based detergent will be recommended. recommended. This is because S odium Hydroxide reacts reacts with Carbon Dioxide, and in closed vessels vess els this can lead, in extreme extreme cases, cases, to tank tank collapse. In atmospheric atmospheric tanks, this reaction is less of a concern, except that the effectiveness of the caustic solution is steadily neutralised by CO2, and as a by-product, by-product, the the reaction reaction generates generates Sodium S odium Carbonate. This degeneration is difficult to detect detect in an automatic automatic CIP CIP system, which uses conductivity instrumentat instrumentation ion to control the the caustic concentrat concentration. ion. In any case case in a brewery application, the caustic should be regularly checked and refreshed as necessary Once the correct chemical is selected, the correct concentration concentration must must be used. Generally, Generally, the supplier’s guidelines should be followed, but given that their business is built on selling chemicals in bulk, their recommendations should be checked with general industry practices. Use of strongly chlorinated products, and strong concentrations of sodium hypochlorite should be avoided if possible, possible, as they they are corrosive to stainless steel. Heat exchangers are particularly vulnerable, due to their very thin plates. When used hot, these these products can contribute contribute to the the causes of stress corrosion cracking in stainless steel tanks. Highly chlorinated products should be rinsed from the





2

TERMINAL SANITISERS

Term Terminal inal Sanit Sanitis iser ers s ar are used sed at the end end of the final inal rin rinse to kill ill any any resid esidu ual or int introdu oduced ced micro icro-organisms in the the plant following following the the final rinse. They are recirculated at CIP velocities and through through tank cleaning heads, and have a defined minimum contact time. The The most ost com commonly only used sed term erminal inal sani sanittiser iser is Perac Peracet etic ic Acid Acid (als (also o know nown as perox eroxy yacet acetic ic acid acid)) (PAA). S ome sanitisers, sanitisers, such as S odium Hypochlorite and Hydrogen Peroxide are highly corrosive to stainless steel, and so should be avoided. P AA is favoured because it breaks down in food to safe and environmentally environmentally friendly friendly residues (water, (water, acetic acid, acid, low strength hy hydrogen drogen peroxide and oxygen). oxygen). It is left left to to drain down following CIP without without any final rinsing. rinsing. As with all chemicals, there are hazards. P AA is a very strong oxidiser, and is very harmful harmful in contact with with the skin or eyes, especially especially in neat form. form. It should never be handled manually manually without without adequate P P E . P AA can present a fire or explosion explosion hazard, hazard, because when it breaks down, it produces oxygen. If PAA P AA is is left in a closed system, it will slowly build build in pressure as the chemical chemical denatures. It is important to leave tanks and pipework to drain following sanitising. P AA is not compatible compatible with natural natural rubbers, so so valve and pipe seals etc. have to be carefully selected, and some dosing systems, which use rubber components are not suitable. F inished beer can be affected by residual P AA in pipework systems, systems, due to oxygen oxygen generation. generation. Where this is critical, for instance instance beer for bott bottling, ling, hot water can be used to purge PAA P AA from the pipework prior to to the beer transfer. transfer. This is not considered a problem in cask beer production.





3

PLANT DESIGN FOR CIP

F or effective effective CIP CIP , the production plant must must be designed correctly. correctly. Hygienic components, components, designed designed for CIP CI P must must be used, with no crevices or dead spots. P ipework systems must must be designed with with no dead legs, and diameters of pipe should be consistent to allow correct CIP velocities in all sections of the pipework pipework route. route. There should s hould be no restrictions to flow rate in the the system (i.e. positive displacement pumps pumps should have a C CIP IP bypass facility). 4

CIP PLANT CONFIGUARTIONS

According to the conditions, capital availability, and preferences of the brewer, a number of systems are available. 4.1

SINGLE TANK CAUSTIC STORAGE SYSTEM

A single single tank CIP system can be used to store and and recirculate caustic in a closed loop. P re rinse and final rinses in this system, are fed directly from the mains, mains, and this is often often difficult to accommodate, given the flowrate required for turbulent flow. Water authority bylaws also restrict direct connection of CIP systems, to their water mains without a break tank. 4.2

SINGLE TANK TOTAL LOSS SYSTEMS SYSTEMS

This This syst system em uses ses a sin single gle tank ank for for all all rinse inses, s, which ich are are drain rained ed at the end end of each each rinse inse cycle. These These systems systems have low capital capital costs, but very high running costs, and are only really really used in critical non-contamination applications like in the pharmaceutical industry.





4.3

MULTI-TANK SYSTEMS SYSTEMS Rinse Water Br eak eak Tank

Used either where the flowrate of mains water in the brewery is insufficient to provide turbulent flow in tthe he pipework, or when there is no other water water break tank in tthe he facility. facility. The water water break tank tank is used used to store enough fresh fresh water for at least one CIP C IP cycle. Recovered Rins e Water Tank Tank

After a detergent cycle, the fresh water used as a post rinse and the terminal sanitisers are collected and re-used as the pre-rinse for the next next CIP CIP cycle. This This sav saves bot both water ater usag usage e and and eff effluen luentt cost costs. s. Detergent Tanks

A tank is used to store a batch of dilute detergent, which is recirculated around the plant and returned back to the detergent tank again. Some larger breweries may use both caustic and acid based detergents in which case the CIP set may have have two two detergent tanks. Use of a detergent tank saves costs of chemicals when compared to single tank total loss systems.

Typ Ty pic ical al Mi Micr crod odat at Rin Rinse se Rec Recov over ery y Sy Syst stem em







5

CIP PLANT DESIGN CONSIDERATIONS 5.1

TANK CLEA NING HEADS HEADS

Modern tank cleaning heads are designed to utilise a jet of fluid. This provides a good scouring action on the tank walls. There are other cleaning, heads usually referred to as spray balls, which provide a lower pressure of spray, which then relies more on temperature, detergent strength and time, to achieve consistent cleaning of the vessel (rather than scouring action).

A Selection of Spray Balls & Rotary Cleaning Heads

The The choi choice ce of clea clean ning ing head ead is oft often a com combin binatio ation n of pric price e vs p per erfform ormance ance.. In a smal smalll diameter vessel, the choice of low cost cleaning heads is greater than in high diameter vessels, where more complex specific designs are required to provide the right jetting action. Ther There e are are oth other fact factor ors s to to cons consid ider er in sele select ctin ing g a clea clean ning ing head ead. Tank Tank clea clean ning ing CIP flow flow rate ate is sometimes matched to the fluid velocity required for cleaning the tank outlet, which is pipesize size dependant. dependant. More usually usually however, however, best practice practice is to use the supply and scavenge pump control, to produce regular cycling of pooling and scavenging in the tank, to provide the outlet pipe cleaning. An important aspect in designing designing the CIP CI P supply pump pump system, is to consider consider the flow and pressure performance curve of the pump, and to match it to the requirements of the cleaning head. If the CIP CIP fluid is presented at too high pressure (at the st stated ated flowrate), flowrate), then then the CIP fluid may atomise into a spray cloud, and conversely, at too low pressure, the intended jet would too weak to be effective. A cheap cleaning head will provide little benefit, in terms of reducing cycle times, and energy and effluent costs. However complex complex cleaning heads from mainstream mainstream suppliers for large vessels can cost upwards of £1000, and are not usually required in smaller breweries. It is important to get the balance right.





5.3

CIP SCAVENGE PUMPS

When cleaning tanks with with a CIP C IP system, a scavenging pump pump is required to return return CIP CIP to the the CIP set. It is important for tank cleaning, that the scavenging pump is capable of pumping a mixture of air and water, water, otherwise otherwise it will easily become air locked. This necessitat necessitates es an expensive style of pump, either a liquid ring pump (which is best), or a self-priming pump. The The scav scaveng enge pump cont contrrol is usual sually ly star startted and and stop stoppe ped d in conj conju unct nction ion with ith the CIP supply pump pump control, to to create a pool of CIP CIP fluid in the the vessel. This is then pumped pumped away at high velocity to match the tank outlet pipework, for effective turbulent flow, thus cleaning the outlet pipe. 5.4

CIP VELOCITY

As explained earlier, it is critical to control flowrates in pipes to provide turbulent flow and therefore provide a scouring action. Tur Turbulen ulentt flow flow is gener enerat ated ed at flow flow veloc elocit itie ies s ab above ove 1.5m .5m/sec /secon ond d. It is recog ecogn nised ised that hat there ere is no benefit in increasing the velocity past 2.1m/second, as diminishing benefits are realised and increases in energy usage and effluent are the only result. Flow rate Table Table For Diff erent Pipe Sizes. Sizes.

P ipesize ipesize 1.0” 1.5” 2.0” 2.5” 3.0”

5.5

Min CIP CI P Velocity Velocity (1.5m/sec) 2.8 m3/hr. 6.3 m3/hr. 11.1 m3/hr. 17.4 m3/hr. 25.0 m3/hr.

INSTRUMENTATION

Ideal CIP Velocity (1.8m/sec) 3.3 m3/hr. 7.5 m3/hr. 13.3 m3/hr. 20.8 m3/hr. 30.0 m3/hr.

Max CIP Velocit Velocity (2.1m/sec) 3.9 m3/hr. 8.7 m3/hr. 15.6 m3/hr. 24.3 m3/hr. 35.0 m3/hr.





5.7

MULTI-CIRCUIT SYSTEMS

Where there is a llot ot of different plant to to be cleaned, a CIP C IP system may may be configured to clean more than one circuit at a time, A two, two, three or four circuit CIP C IP system may may be provided, serviced by the same tanks.

A 4 Circuit Mult Multi-Tank i-Tank CIP System 6

MICRODAT

Microdat manufactures a full range of brewery equipment from malt intake to cask washing and filling. Microdat’s process division division is expert in designing designing plant suitable for CIP and Microdat has a range of standard low cost, and bespoke CIP systems. systems.

4da2c21238509 Cleaning in Place Systems Design Manual

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