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Important Safety Information 

Introduction 

All practical work areas and laboratories should be covered by local safety 
regulations 

which must be followed at all times

It is the responsibility of the owner to ensure that all users are made aware of 
relevant local regulations, and that the apparatus is operated in accordance with 
those regulations. If requested then Armfield can supply a typical set of standard 
laboratory safety rules, but these are guidelines only and should be modified as 
required. Supervision of users should be provided whenever appropriate. 

Your 

CEM-MKII Continuous Stirred Tank Reactor

 has been designed to be safe in 

use when installed, operated and maintained in accordance with the instructions in 
this manual. As with any piece of sophisticated equipment, dangers exist if the 
equipment is misused, mishandled or badly maintained. 

Water Borne Hazards 

The equipment described in this instruction manual involves the use of water, which 
under certain conditions can create a health hazard due to infection by harmful 
micro-organisms. 

For example, the microscopic bacterium called Legionella pneumophila will feed on 
any scale, rust, algae or sludge in water and will breed rapidly if the temperature of 
water is between 20 and 45°C. Any water containing this bacterium which is sprayed 
or splashed creating air-borne droplets can produce a form of pneumonia called 
Legionnaires Disease which is potentially fatal. 

Legionella is not the only harmful micro-organism which can infect water, but it 
serves as a useful example of the need for cleanliness. 

Under the COSHH regulations, the following precautions must be observed: 

 

Any water contained within the product must not be allowed to stagnate, ie. 
the water must be changed regularly. 

 

Any rust, sludge, scale or algae on which micro-organisms can feed must be 
removed regularly, i.e. the equipment must be cleaned regularly. 

 

Where practicable the water should be maintained at a temperature below 
20°C. If this is not practicable then the water should be disinfected if it is safe 
and appropriate to do so. Note that other hazards may exist in the handling of 
biocides used to disinfect the water. 

 

A scheme should be prepared for preventing or controlling the risk 
incorporating all of the actions listed above. 

Further details on preventing infection are contained in the publication “The Control 
of Legionellosis including Legionnaires Disease” - Health and Safety Series booklet 
HS (G) 70. 

 

Содержание CEM-MKII

Страница 1: ...Continuous Stirred Tank Reactor Instruction Manual CEM MKII ISSUE 20 September 2013...

Страница 2: ...Chemical Safety 6 Description 7 Overview 7 Flow of materials 7 Installation 9 Advisory 9 Installing the PC Software 9 Installing the Equipment 9 Operation 12 Operating the PC Software 12 Operating the...

Страница 3: ...mon Theory 22 Exercise A To find the reaction rate constant in a Continuous Stirred Tank Reactor 24 Exercise B To determine the effect of inadequate mixing on the reaction rate 29 Exercise C Determina...

Страница 4: ......

Страница 5: ...Customer Support helpdesk Monday to Thursday 0830 1730 and Friday 0830 1300 UK time Contact details are as follows United Kingdom International 0 1425 478781 calls charged at local rate 44 0 1425 4787...

Страница 6: ...th the CEXC Computer Controlled Service Unit An alternative instruction manual is available from Armfield that describes the use of the CEM MKII in conjunction with the CEX Service Unit Please contact...

Страница 7: ...rticularly suitable for liquid phase reactions It is particularly used in the organic chemicals industry Advantages include consistent product quality straightforward automatic control and low manpowe...

Страница 8: ...4 Equipment Diagrams Figure 1 Reactor Unit...

Страница 9: ...a will feed on any scale rust algae or sludge in water and will breed rapidly if the temperature of water is between 20 and 45 C Any water containing this bacterium which is sprayed or splashed creati...

Страница 10: ...ressed Failure to trip means that the operator is not protected and the equipment must be checked and repaired by a competent electrician before it is used Hot Surfaces and Liquids The unit incorporat...

Страница 11: ...ensors provided with the service unit The larger of the two glands is for the conductivity probe The glands are unscrewed by hand the probes inserted completely into the reactor until they rest on the...

Страница 12: ...Armfield Instruction Manual 8 CEM MKII Continuous Stirred Tank Reactor...

Страница 13: ...e top right hand corner of the screen as shown below Note that when operating the software for the first time it will be necessary to enable the USB virtual COM port by choosing the Red telephone icon...

Страница 14: ...e reactor The gland nut should be loosened prior to fitting the probe sensor then tightened to secure them CEXC fitted with CEM MkII Continuous Stirred Tank Reactor Connection to the Hot Water Circula...

Страница 15: ...EM software then choose the appropriate experiment from the menu For detailed information about operating the software refer to the section Operating the PC Software Display the mimic diagram by choos...

Страница 16: ...r of the unit should be turned on before hand Both the temperature controller and conductivity display should illuminate Filling the feed bottles Unscrew the feed bottle caps and pour appropriate reag...

Страница 17: ...and control of the heater stirrer and pumps Recorded results can be displayed in tabular and graph format The software runs on a WindowsTM PC which connects to the CEXC using a USB interface Installa...

Страница 18: ...e used with an optional Chiller CW 17 for operating temperatures below ambient The use of the heater or chiller is chosen in the initial menu when loading the CEM software When using the hot water cir...

Страница 19: ...ontinuously to correct for any error The hot water temperature T2 is chosen as the default process variable to provide a stable temperature T1 inside the reactor Control of T1 directly would be diffic...

Страница 20: ...ection for appropriate controller settings when using the CW 17 When using the Heater the temperature sensor T1 supplied with CEXC which is Reactor Temperature on the software should be set as the Pro...

Страница 21: ...erator a Indoor use b Altitude up to 2000m c Temperature 5 C to 40 C d Maximum relative humidity 80 for temperatures up to 31 C decreasing linearly to 50 relative humidity at 40 C e Mains supply volta...

Страница 22: ...is located on a printed circuit board inside the plinth on the right hand side This circuit is calibrated before despatch and should not require re calibration However should re calibration become ne...

Страница 23: ...ion Range 0 20 mS cm Fill a small beaker with a Conductivity standard solution e g 0 1M KCI giving a conductivity of 12 88mS at 25 C and measure the temperature of the standard solution using a suitab...

Страница 24: ...a reading of the Standard solution in the Low conductivity window on the software Remove the probe from the conductivity solution and rinse the probe in de mineralised water When the conditioning circ...

Страница 25: ...o sodium hydroxide conc in mixed feed mol dm3 a1 sodium hydroxide conc in reactor at time t mol dm3 sodium hydroxide conc in reactor after time mol dm3 b ethyl acetate conc mol dm3 same subscripts as...

Страница 26: ...er The conductivity of the reacting solution in the reactor changes with the degree of conversion and this provides a convenient method for monitoring the progress of the reaction either manually or b...

Страница 27: ...ate as follows Therefore add 9 79ml of concentrated Ethyl Acetate to 900ml of deionised or distilled water Shake the mixture vigorously until the two liquids have mixed Add further water to make up th...

Страница 28: ...ve the caps of the reagent bottles and carefully fill with the reagents to a level approximately 50mm from the top using a funnel if necessary Refit the caps Start the software using the option of the...

Страница 29: ...at the same molarity and temperature and a relationship has been established allowing conversion to be inferred from conductivity The calculations are best carried out using a spreadsheet such as EXCE...

Страница 30: ...calculate values of sodium hydroxide concentration a1 and sodium acetate concentration c1 and the degree of conversion Xa and Xc for each of the samples of conductivity taken over the period of the ex...

Страница 31: ...ate and the conversion Notes 1 It is recommended that this experiment should be repeated at various other temperatures to investigate the relationship between the specific rate constant k and the temp...

Страница 32: ...ree different temperatures is known is straightforward to apply the Arrhenius law and calculate the frequency factor and the activation energy values for Plotting Rate constant vs Temperature Obtentio...

Страница 33: ...e initial concentrations are equal both a0 and the conversion Xa then the concentrations are as follows NaOH CH3COOC2H5 C2H5OH CH3COONa a0 Xa a0 Xa Xa Xa Method Repeat Exercise A after removing the ba...

Страница 34: ...d this is achieved using the hot water circulator and setting the PID temperature controller in the software as detailed in previous experiments Start the water feed pump by setting the pump speed con...

Страница 35: ...e the Neperian logarithm of Plot vs time and calculate the slope straight line graph passing through the origin The slope is the average residence time tR which should be equal to where V is the react...

Страница 36: ...for a working volume of 1369ml and a working flow rate of 106 5ml min The difference between the theoretical and the experimental value may be caused by experimental errors such inaccuracies on the m...

Страница 37: ...West Street Ringwood Hampshire England BH24 1DY Tel 44 0 1425 478781 Fax 44 0 1425 470916 Email sales armfield co uk support armfield co uk Web http www armfield co uk US Office Armfield Inc 9 Trento...

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