Velp Scientifica UDK 139 User manual

10004762/B5
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UDK 139
Semi-automatic Distillation Unit
Operating manual
Velp Scientifica thanks you for choosing the UDK 139 Semi-automatic Distillation Unit. The
UDK 139 is designed to perform nitrogen and protein content determination according to the
Kjeldahl Method (TKN) in the Food & Feed industry and has several other applications in
environmental control (nitrogen in water, soil and lubricants) and in the chemical and
pharmaceutical industry according to official AOAC, EPA, DIN e ISO procedures.
Safety warnings:
Before using the unit, please read the operating manual supplied with the apparatus
carefully.
Warning! Hot surface!
Do not dispose of this equipment as urban waste
This unit must be used for laboratory applications only.
The manufacturer declines all responsibility for any use of the unit that does not comply with
the instructions.
SAFETY PRECAUTIONS
In order to prevent the risk of electric shock, fire and personal injury when the unit is in use,
basic safety measures must always be taken including:
Ensure that liquids do not come into contact with the electric power cable or with the
electrical parts of the instrument.
Check that the power supply corresponds to the rating plate on the rear of the unit.
When replacing the power cable, make sure that the new cable has the same
characteristics as the original and that it is earthed.
Do not use the unit if it is not working correctly. In case of malfunctioning, contact your
nearest service centre.
The personal protective equipment must be compatible with the possible risks posed by
the material being processed and the glass of the containers.
The test tube reaches a temperature of 100°C during distillation and also during the
cooling phase. Use the pincer supplied to remove the test-tube at the end of distilling.
The vessels and the products used during the work-cycle must be compatible with the
temperatures reached by the unit (approx. 100°C).
For further information on the handling of the reagents see Chapter 2 “Chemicals”.
Leave the transparent guard in place when the unit is running.
Follow the cleaning instructions described in this manual
The safety of the instrument is no longer guaranteed in the case of improper use or if the
instructions in this manual are not followed.
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RÈGLES DE SÉCURITÉ
Pour éviter tout risque de choc électrique, incendie ou blessure corporelle pendant l'utilisation
de l'appareil, toujours appliquer les mesures de sécurité de base, y compris les
recommandations suivantes :
S'assurer que les liquides n'entrent pas en contact avec le cordon d'alimentation ou avec
toute autre pièce électrique à l'intérieur de l'appareil.
Vérifier que le cordon d'alimentation est inséré dans une prise électrique (dans une
position facilement accessible) correspondant aux valeurs décrites sur la plaque de
l'appareil.
Utiliser uniquement des cordons d'alimentation à trois bornes, c'est-à-dire avec cordon de
mise à la terre.
Ne pas utiliser l'appareil en cas de dysfonctionnement. Si cela se produit, contacter le
Service Après-Vente le plus proche.
Les équipements de protection individuelle doivent être compatibles avec les risques
encourus pour les matériaux à traiter et le verre des récipients.
Le tube à essai atteint une température de 100°C pendant la phase de distillation, mais
également pendant la phase de refroidissement. Utiliser les pinces fournies pour retirer le
tube à la fin de la distillation.
Les récipients et les produits utilisés pendant les analyses doivent être compatibles avec la
température réglée sur l'appareil (environ 100°C).
Pour toute autre information sur l'utilisation des réactifs utilisés, voir Chapitre 2 “Produits
chimiques”.
S'assurer que la protection transparente est en place lorsque l'appareil fonctionne.
Respecter les instructions d'entretien de l'appareil décrites dans ce manuel.
Le fabricant décline toute responsabilité pour toute utilisation de l'appareil non conforme à ces
instructions.
This unit has been designed and produced in compliance with the following standards:
Safety requirements for electrical apparatus for
measurement and control and for laboratory use IEC/EN 61010-1
IEC/EN 61010-2-010
IEC/EN 61010-2-081
UL Std. 61010-1 2nd Ed.
CAN/CSA 61010-1-04 2nd Ed.
CAN/CSA 61010-2-010-04
CAN/CSA 61010-2-081
Electrical equipment for measurement, control
and laboratory use - EMC requirements IEC/EN 61326-1 (2006)
FCC CFR 47 Part 15 Sub part B
Restrictions of the use of certain hazardous substances
in electrical and electronic equipment 2011/65/EU (RoHS)
On waste electrical and electronic equipment (WEEE) 2002/96/EC (WEEE)
The manufacturer is committed to constantly improving the quality of the products and reserves
the right to modify the characteristics without prior notice.
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CONTENTS
1.1.Parts included..........................................................................................................6
1.2.Instrument description.............................................................................................7
2. Chemicals..............................................................................................................10
2.1.Products used .......................................................................................................10
2.2.Substances generated by digestion and distillation................................................11
3. Assembly and installation.......................................................................................12
3.1.Hydraulic connections ...........................................................................................13
3.2.Connection to the electric power supply.................................................................14
3.3.Connection to external devices..............................................................................15
3.4.Printer 15
3.4.1. Mouse..........................................................................................................16
3.5.Preliminary operations...........................................................................................16
4. Using the menus....................................................................................................17
4.1.Quick Guide ..........................................................................................................17
4.2.Main menu ............................................................................................................19
4.3.Analysis 21
4.3.1. Wash-down..................................................................................................21
4.3.2. Distillation ....................................................................................................23
4.4.Methods 26
4.5.Set-up 28
4.6.System 31
4.6.1. Check-up .....................................................................................................31
4.6.2. Calibration....................................................................................................38
4.6.3. Maintenance ................................................................................................39
4.6.4. Service.........................................................................................................40
5. Operating Controls.................................................................................................42
5.1.Safety devices, signals and warnings ....................................................................42
5.1.1. Safety devices..............................................................................................42
5.1.2. Reserves and overfilling...............................................................................43
5.1.3. Warning signals and messages....................................................................44
5.1.4. Black-out......................................................................................................45
5.2.Graph of steam production....................................................................................45
5.3.Graph of tap water consumption related to the water flow rate and temperature....46
6. Work cycle.............................................................................................................47
6.1.Analysis 47
6.2.Devarda’s analysis ................................................................................................47
7. End-of-work operations..........................................................................................48
8. Maintenance..........................................................................................................49
8.1.Routine maintenance.............................................................................................49
8.2.Extraordinary maintenance....................................................................................50
8.2.1. Periodic maintenance...................................................................................50
8.2.2. Operations to be performed only when necessary........................................52
8.3.Expedients for transport.........................................................................................53
9. Disposing of the unit...............................................................................................54
10. Accessories ...........................................................................................................54
11. Spare parts............................................................................................................55
12. Technical features..................................................................................................56
13. Wiring diagram.......................................................................................................58
14. Hydraulic scheme ..................................................................................................60
15. Warranty 62
16. Suggestions...........................................................................................................62
17. General description of Kjeldahl's method for the measurement of organic Nitrogen63
18. AOAC, method 960.52, Microchemical determination of nitrogen- Micro-Kjeldahl
method ..............................................................................................................68
19. Analytical procedure Typical analytical scheme for organic Nitrogen......................70
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20. Analytical Methods.................................................................................................71
1 - Kjeldahl method to determine the protein content on milk and derived products......71
2 - Kjeldahl method to determine the protein content on almonds, nuts, hazelnuts.......72
3 - Kjeldahl method to determine the protein content on coconuts................................73
4 - Kjeldahl method to determine the protein content on peanuts and Brazil nuts.........74
5 - Kjeldahl method to determine the protein content on beer.......................................75
6 –Kjeldahl method to determine the protein content on barley malt............................76
7 - Kjeldahl method to determine the protein content on cereals and feed....................77
8 - Kjeldahl method to determine the protein content on wheat....................................78
9 - Kjeldahl method to determine the protein content on oats, barley, corn, rice, rye ....79
10 - Kjeldahl method to determine the protein content on soya beans and lupins.........80
11 - Kjeldahl method to determine the protein content on canned cat/dog food............81
12 - Kjeldahl method to determine the protein content on forage and straw..................82
13 - Kjeldahl method to determine the protein content on bacon, ham, hot dog, salami,
sausage ...............................................................................................................83
14 - Kjeldahl method to determine the protein content on meat and derived products..84
15 - Kjeldahl method to determine the protein content on bread and baked products...85
16 - Kjeldahl method to determine the protein content on compressed and granular
yeast ...............................................................................................................86
17 - Kjeldahl method to determine the protein content on liver patè .............................87
18 - Kjeldahl method to determine the protein content on sugar, syrup, molasses........88
19 - Kjeldahl method to determine the protein content on wheat spaghetti and macaroni,
egg pasta ...............................................................................................................89
20 - Kjeldahl method to determine the protein content on grain spaghetti, macaroni ....90
21 - Kjeldahl method to determine the protein content on plants (vegetable)................91
22 - Kjeldahl method to determine the protein content on mushrooms .........................92
23 - Kjeldahl method to determine total nitrogen on crude oil and fuels (ISO n. 333)....93
24 - Kjeldahl method to determine total nitrogen on ABS, SAN, rubber........................94
25 - Kjeldahl method to determine total nitrogen in urea...............................................95
26 - Kjeldahl method to determine total nitrogen on water............................................96
27 - Kjeldahl method to determine total nitrogen on soil...............................................97
28 - Kjeldahl method to determine gelatin on paper .....................................................98
29 - Kjeldahl method to determine casein on paper......................................................99
30 - Kjeldahl method to determine total nitrogen on sludges from wastewater treatment
plants .............................................................................................................100
31 - Method to determine the alcohol strength on wines, musts and spirits by steam
distillation and volume................................................................................................101
32 - Method to determine the residual urease activity in soya beans..........................103
33 - Method to determine urea nitrogen in feed and roughages..................................104
34 - Determination of the volatile acidity of tomato paste............................................105
35 - Method to determine the volatile acidity of wines.................................................107
36 - Kjeldahl’s method to determine total nitrogen in crude oil, lubricants and fuel oils
(ASTM, D3228-96).....................................................................................................110
37 - Method to determine nitric nitrogen on water after reduction to ammonia nitrogen
(Devarda’s alloy method) ...........................................................................................112
38 - Method to separate ammonia in water from interfering substances.....................113
39 - Determination of phenols in drinking water and in industrial wastes....................114
40 - Separation of hydrocyanic acid from wastewaters...............................................116
41 - Method to control the efficiency of an anaerobic digester by determination of volatile
acids content in digesting sludge................................................................................118
42 - Determination of ammonia nitrogen in organic fertilizers according to the Kjeldahl
method .............................................................................................................120
43 - Determination of the total volatile basic nitrogen (TVBN) in fresh and frozen fish 121
21. Declaration of conformity .......................................................................122
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Introduction
Steam distillation is applied in the laboratory for the fractionation of water insoluble
liquids or solids according to Dalton's law of partial pressures in a gas mixture.
It is also used for stripping chemicals from mixtures or solutions after displacement of
the ionic equilibrium by adding acids or bases, as in the well known Kjeldahl's
method for total Nitrogen determination.
The Kjeldahl method remains the most used method for determining Nitrogen and
protein contents in foods and feeds (official methods).
This is simply due to its precision and reproducibility.
Since its initial design, many improvements have been introduced aimed at reducing
energy consumption, space requirements and sample quantities.
The UDK 139 Semi-automatic Distillation Unit has a color touch-screen with
electronic control for simple and user-friendly programming of parameters such as
distillation time, the volume of reagents such as sodium hydroxide, water and the
regulation of steam production from 10 to 100% in order to carry out Semi-automatic
distillation.
By modifying the distillation time and steam output it is possible to carry out fast or
slow distillation according to the product being analyzed. For example, the distillation
time for the determination of the protein content according to the Kjeldahl method
can be reduced to three minutes. In other cases (e.g. volatile acids in food products),
the distillation time can be increased to 30 minutes or more.
Analysis times are reduced thanks to the optimization of the applications:
10 programs that can be customized directly by the user.
NOTE: the software can be browsed directly from the touch-screen. Select the option
by hand, using a stylus or a mouse.
3
4
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1.1. Parts included
Check that the unit is complete after unpacking.
The table below shows the parts included:
Description
Code
Q.ty
UDK 139 Semi-automatic
Distillation Unit 1
F30200130
1
Test tube Ø 42 x 300 mm 2
A00001080
1
Collecting flask 250 ml
(used only without titration)
10001106
1
Pincer for test tube
10000247
1
Touch pen
10004936
1
Inlet tube
10000280
1
Tubes with sensors:
Inlet tube for H2O
Inlet tube for NaOH
Outlet tube for distillation
residues
40000153
40001023
40000387
3
- Discharge tubes:
- Silicone tube Ø 6x9mm
PVC tube Ø10x14
10000020
10001087
2
The operating manual is inside the distillation unit1box .
The test tube2is not sold separately (see chap. 10 Accessories).
The protective film for touch screen (code 40001798) is already placed on the
display.
NOTE: Keep the special shock-resistant packing material for future use.
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1.2. Instrument description
The UDK 139 Semi-automatic Distillation Unit uses innovative technology and
advanced electronics for the automation of the various stages and the highest
standards of reliability and safety.
The UDK 139 carries out all the stages of the distillation process such as the addition
of single reagents and the removal of distillation residues automatically.
Main components of the distillation unit:
1 Color Touch Screen with protective film
2 On/Off switch
3 Service door catch
4 Flask stand
5 Safety guard
6 Lever for insertion of test tube
7 Test tube press
8 Test tube connection
9 Plastic guard for test tube connection
10 Socket panel
11 Distillate outlet tube
The Semi-automatic distillation unit UDK139 is fitted with innovative devices and is
manufactured using innovative materials and advanced technology:
The instrument has a polymer structure that ensures greater resistance
against chemical reagents used during analysis and a high durability.
2
5
6
3
1
7
8
4
9
11
10
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The patented Velp Scientifica steam generator uses deionised or distilled water
and produces a constant and stable quantity of steam ensuring the
reproducibility of the analysis without requiring any routine maintenance. The
steam flow is controlled by a software which enables the user to choose
between rapid or slow distillations according to the product to be analyzed.
The innovative titanium condenser achieves outstanding heat exchange,
reduces water consumption, offers higher resistance than glass and is easily
and thoroughly cleaned. The display shows the water consumption during each
analysis.
The new technopolymer splash head assures optimal resistance to the high
temperatures and corrosive chemicals involved during the distillation process.
The graphic touch screen with its simple and user-friendly interface, enables
the user to program all the automatic distillation / titration parameters. The
protective film on the touch screen safeguards against wear and against the
majority of laboratory agents.
Choose from 6 different languages to communicate with the instrument.
The distillation unit can be connected to a printer via USB in order to print all the
information pertaining to the tests performed in accordance with GLP (Good
Laboratory Practice).
The UDK 139 ensures the highest safety standards: it signals the absence of
the test tube, test tube exchange at the end of analysis, safety guard open, the
absence of reagents and the absence of cooling water. The use of an innovative
system enables the operator to position the test tube in complete safety and
means that test tubes of various sizes can be used.
In a world where respect for the environment is increasingly important, the
distillation unit UDK 139 makes a significant contribution to this cause. The
cooling water supply shuts-off automatically during pauses considerably
reducing water consumption and the technopolymer housing is 100%
recyclable.
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The UDK series guarantees unmatched savings whist ensuring an extremely high
level of reliability.
The UDK139 is exceptional in providing savings, by using TEMSTM technology:
Time: Fast and frequent analyses; no heating delay between runs.
Energy: Cooling water consumption starting from only 0.5 l/min; excellent insulation
of internal parts.
Money: Cost reduction is substantial, in line with reduced power consumption.
Space: The extremely compact footprint saves useful laboratory bench space.
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2. Chemicals
2.1. Products used
The chemicals used for distillation and titration are potentially dangerous and must
be handled with care and with personal protective equipment: gloves, goggles and
pincer removal of the reaction hot test-tubes.
1) Boric acid (H3BO3): 4% solution. The low concentration is due to the fact that
boric acid crystallizes at low temperatures and this can cause problems in the
hydraulic circuits of the instrument. Ingestion or absorption may cause nausea,
vomiting and diarrhea. Diluted solutions are used as an antisceptic.
2) Sodium hydroxide (NaOH): Velp recommends a 30-35% w/v solution of sodium
hydroxide in order to avoid violent reactions in the test-tube. Corrosive to all body
tissues. Can cause severe burns. Protect the skin and the eyes. If the solution is
prepared using flakes or pellets, add these to water and not vice versa. Ingestion can
cause vomiting, prostration, collapse. Constrictive scarring can occur.
Caution: in case of ingestion DO NOT attempt to evacuate the stomach.
Chemicals used during the digestion phase:
3) Sulphuric Acid (H2SO4): concentrated (96-98%). Corrosive to all body tissues.
Skin contact can produce necrosis. Protect the skin and the eyes. When diluting, the
acid must be added to the diluent to prevent the generation of excessive heat and
the danger of splashes. Neutralize spills with dry sodium bicarbonate or calcium
carbonate powder.
4) Hydrogen peroxide (H2O2): 30% w/w. Can cause severe burns. Wear goggles
and rubber gloves. Avoid contact with combustible materials: drying of concentrated
solutions on paper, clothing and so on, can cause combustion. Heavy metals and
their salts, dust, irregular surfaces, can cause rapid decomposition resulting in the
production of oxygen and increased pressure. Stored hydrogen peroxide solutions
decompose slowly but nevertheless bottles must be fitted with vent caps. Empty
bottles must be rinsed with clean water. In case of contact, rinse immediately with
plenty of water.
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