Buchi K-350 User manual

K-350 Distillation Unit
Operation Manual
093031G en

Imprint
Product Identification:
Operation Manual (Original), Distallation Unit K-350
093031G en
Publication date: 04.2016
BÜCHI Labortechnik AG
Meierseggstrasse 40
Postfach
CH-9230 Flawil 1
E-Mail: [e-mail]
BUCHI reserves the right to make changes to the manual as deemed necessary in the light of experience; espe-
cially in respect to structure, illustrations and technical detail.
This manual is copyright. Information from it may not be reproduced, distributed, or used for competitive purpos-
es, nor made available to third parties. The manufacture of any component with the aid of this manual without
prior written agreement is also prohibited.

Table of contents
3K-350 Operation Manual, Version G
Table of contents
1 About this manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.1 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.1 User qualification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Proper use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Improper use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Warning notices used in this manual . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5 Product safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.5.1 Instrument-related hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5.2 Other hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
2.5.3 Safety measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.5.4 Safety elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
2.6 General safety rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.1 Standard instrument. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.2 Standard accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1.3 Optional accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.3 Materials used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4 Description of function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1 Instrument overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.2 Function principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.3 Controls of the instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5 Putting into operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.1 Installation site. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.2 Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.3 Reagent and water connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.3.1 Cooling water connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.3.2 Drainage of cooling water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.3.3 Storage tank connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Read this manual carefully before installing and running your system and note the safety precautions
in chapter 2 in particular. Store the manual in the immediate vicinity of the instrument, so that it can be
consulted at any time.
No technical modifications may be made to the instrument without the prior written agreement of
BUCHI. Unauthorized modifications may affect the system safety or result in accidents.
This manual is copyright. Information from it may not be reproduced, distributed, or used for competi-
tive purposes, nor made available to third parties. The manufacture of any component with the aid of
this manual without prior written agreement is also prohibited.
If you need another language version of this manual, you can download it at
www.buchi.com.

Table of contents
4K-350 Operation Manual, Version G
6 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.1 Addition of chemicals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.1.1 Manual dosage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.1.2 Automatic dosage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.1.3 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.2 Setting the distillation time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.3 Steam generator status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.3.1 Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.3.2 Standby mode (after 30 minutes) . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.4 Switching ON/OFF checklist. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.5 Carrying out a Kjeldahl distillation . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
7 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1 Daily maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1.1 Cleaning the instrument from inside . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1.2 Cleaning the housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1.3 Cleaning the glass parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7.1.4 Preparing the instrument for a standstill overnight . . . . . . . . . . . . . . . . . . . 26
7.2 Weekly maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.2.1 Cleaning the splash protector and the rubber bung seal. . . . . . . . . . . . . . . . 26
7.3 Monthly maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.3.1 Checking the distillate amount. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.4 Half-yearly maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.4.1 Replacing the NaOH tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.5 Yearly maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.5.1 Replacing the rubber bung seal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.5.2 Replacing the NaOH pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.6 Customer service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
8 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
8.1 Malfunctions and their remedy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
9 Shutdown, storage, transport and disposal . . . . . . . . . . . . . . . . . . . . . . . . 29
9.1 Preparing the instrument for transport . . . . . . . . . . . . . . . . . . . . . . . . . 29
9.2 Storage and transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
9.3 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10 Spare parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
10.1 Spare parts K-350 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
10.2 Hosing connection scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
11 Declarations and requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
11.1 FCC requirements (for USA and Canada) . . . . . . . . . . . . . . . . . . . . . . . 33

1 About this manual
5K-350 Operation Manual, Version G
1 About this manual
This manual describes the Distillation Unit K-350 and provides all information required for its safe
operation and to maintain it in good working order.
It is addressed to laboratory personnel in particular.
NOTE
The symbols pertaining to safety (WARNINGS and ATTENTIONS) are explained in chapter 2.
1.1 Abbreviations
EPDM: Ethylene Propylene Dimonomer
FEP: Fluorinated Ethylene Propylene
FPM: Fluoroelastomer
PP: Polypropylene
PTFE: Polytetrafluoroethylene
RSD: Relative Standard Deviation

2 Safety
6K-350 Operation Manual, Version G
2 Safety
This chapter points out the safety concept of the instrument and contains general rules of behavior
and warnings from hazards concerning the use of the product.
The safety of users and personnel can only be ensured if these safety instructions and the safety-
related warnings in the individual chapters are strictly observed and followed. Therefore, the manual
must always be available to all persons performing the tasks described herein.
2.1 User qualification
The instrument may only be used by laboratory personnel and other persons who on account of
training or professional experience have an overview of the dangers which can develop when
operating the instrument.
Personnel without this training or persons who are currently being trained require careful instruction.
The present Operation Manual serves as the basis for this.
2.2 Proper use
The instrument has been designed and built for laboratories. It serves for the distillation of steam-
volatile substances.
2.3 Improper use
Applications not mentioned above are improper. Also, applications which do not comply with the tech-
nical data are considered improper.
The operator bears the sole risk for any damages caused by such improper use.
The following uses are expressly forbidden:
• Use of the instrument in rooms which require ex-protected instruments.
• Use on samples, which can explode or inflame (e.g. explosives, etc.) due to shock, friction, heat or
spark formation.

2 Safety
7K-350 Operation Manual, Version G
2.4 Warning notices used in this manual
WARNING
Generally, the triangular warning symbol indicates the possibility of personal injury or even loss of life
if the instructions are not followed.
WARNING
Hot surface.
WARNING
Electrical hazard.
WARNING
Corrosive substances.
ATTENTION
With the general „Read this” symbol, ATTENTIONs indicate the possibility of equipment damage,
malfunctions or incorrect process results, if instructions are not followed.
NOTE
Useful tips for the easy operation of the instrument.
2.5 Product safety
The instrument is designed and built in accordance with state-of-the-art technology. Nevertheless,
risks to users, property, and the environment can arise when the instrument is used carelessly or
improperly.
The manufacturer has determined residual dangers emanating from the instrument
• if the instrument is operated by insufficiently trained personnel.
• if the instrument is not operated according to its proper use.
Appropriate warnings in this manual serve to make the user alert to these residual dangers.
2.5.1 Instrument-related hazards
Pay attention to the following safety notices:
WARNING
Potential implosion risk if used with damaged glassware.
• Beware of damaged or cracked glass parts.
WARNING
Potentially hot surfaces during operation (surfare temperatures at times exceed 60 °C) and hot steam
passing off the waste outlet.
• Always be aware of the risk of being burned.
WARNING
Potentially lethal voltage inside the instrument.
• Do not remove covers and other parts protecting from electricity.
• Always keep the areas of electric parts, such as power supply plug, mains switch, etc. dry.

2 Safety
8K-350 Operation Manual, Version G
2.5.2 Other hazards
WARNING
Certain solvents in or in the vicinity of the instrument can form peroxides and/or are highly inflam-
mable.
• Always be aware of the explosion risk when working with hazardous substances or with
substances of unknown composition.
• Always provide a good ventilation within or in the vicinity of the system.
2.5.3 Safety measures
WARNING
Sodium hydroxide, acids and lye are used for applications according to Kjeldahl. For this reason,
protective goggles must be worn at all times when using the instrument or working in its immediate
proximity.
2.5.4 Safety elements
The instrument is provided with the following safety elements:
• Protective door: Safety appliance to protect users from burns at the splash protector (distillation
area), which is hot during distillation.
• Protective door sensor: Prevents the start of a distillation with the protective door open and stops
a running distillation and the dosing of reagents immediately when the protective door is opened
during the process.
• Sample tube sensor: Prevents the start of a distillation without a sample tube inserted.
• Protective shield (cover) at condenser: Protection of glass parts.
• Service door sensor/switch: Electrical power is disconnected immediately when the service door is
opened, thus preventing electrical shock during maintenance.

2 Safety
9K-350 Operation Manual, Version G
2.6 General safety rules
Responsibility of the operator
The head of laboratory is responsible for training his personnel.
The operator shall inform the manufacturer without delay of any safety-related incidents which might
occur during operation of the instrument. Legal regulations, such as local, state and federal laws
applying to the instrument must be strictly followed.
Duty of maintenance and care
The operator is responsible for ensuring that the instrument is operated in proper condition only, and
that maintenance, service, and repair jobs are performed with care and on schedule, and by autho-
rized personnel only.
Spare parts to be used
Use only genuine consumables and genuine spare parts for maintenance to assure good system
performance and reliability. Any modifications to the spare parts used are only allowed with the prior
written permission of the manufacturer.
Modifications
Modifications to the instrument are only permitted after prior consultation with and with the written
approval of the manufacturer. Modifications and upgrades shall only be carried out by an authorized
BUCHI technical engineer. The manufacturer will decline any claim resulting from unauthorized modifi-
cations.

3 Technical data
10 K-350 Operation Manual, Version G
3 Technical data
This chapter introduces the reader to the instrument specifications. It contains the scope of delivery,
technical data, requirements and performance data.
3.1 Scope of delivery
Check the scope of delivery according to the order number.
NOTE
For detailed information on the listed products see www.buchi.com or contact your local dealer.
3.1.1 Standard instrument
Table 3-1: Standard instrument
Product Order number
Distillation Unit K-350 Standard with
glass splash protector, 230 V, 50/60 Hz
43500
Distillation Unit K-350 with splash
protector made of fiber glass reinforced
polypropylene, 230 V , 50/60 Hz
43418

3 Technical data
11 K-350 Operation Manual, Version G
3.1.2 Standard accessories
12
Table 3-2: Standard accessories
Product Order number
a1 mains cable of the following types
Type CH 10010
Type Schuko 10016
Type GB 17835
Type AUS 17836
Type USA 33763
Type Japan 10016
b1 pair of glass tongs 02004
3
45
67
8
c1 cooling water hose complete: G ¾",
½", L = 1.5 m
37780
d1 hose chemical supply, solaflex,
L = 3.5, Ø 10/5 mm
43555
e 1 hose cooling water drain, silicone,
L = 1.5 m
43940
f1 clamp Ø 9.6 mm 27738
f2 clamps Ø 11.9 mm 43841
g 1 hose tygon, L = 530 mm 43029
h 2 suction tubes to tanks, FEP,
L = 580 mm
43407
9
10
11
12
i 2 tanks 10 l, without caps 43410
j2 caps for 10 l tanks, large 25869
k2 tank labels 43434
l3 caps for 10 l and 20 l tanks, small 43477

3 Technical data
12 K-350 Operation Manual, Version G
3.1.3 Optional accessories
123
Table 3-3: Optional accessories K-350
Product Order number
a 1 sample tube 500 mL 26128
b 1 sample tube (set of 4) 300 mL 37377
c Condenser cover, complete 43484
4
5
d 20 l tank for chemicals 43469
e 10 l tank for chemicals 43468
6
7
f Holder for 4 sample tubes, 500 mL 16951
g Holder for 6 sample tubes, 300 mL 43039
8
h Holder for 12 sample tubes, 300 mL 43041

3 Technical data
13 K-350 Operation Manual, Version G
Table 3-3: Optional accessories K-350 (cont.)
Product Order number
Splash protector for Devarda method
K-350/K-355/K-370
43335
Constricted distillate outlet tube Ø 5 mm 43096
Sample tubes graduated, 300 mL, set of
4
43049

3 Technical data
14 K-350 Operation Manual, Version G
Table 3-3: Optional accessories K-350 (cont.)
Product Order number
Universal adapter for K-350, K-355 or
K-370
43115
SO2accessory 48680

3 Technical data
15 K-350 Operation Manual, Version G
3.2 Technical data
Table 3-4: Technical data K-350
Distillation Unit K-350
Power consumption max. 2.2 kW
Connection voltage 230 V ± 10 % / 200 V ± 10 %
Frequency 50/60 Hz
Current consumption (230 V) 8.5 A
Mains connection 3-pole (P, N, E) via power cord
Recovery rate ≥ 99.5 %
Reproducibility (RSD) ≤ 1 %
Detection limit ≥ 0.1 mg Nitrogen
Environmental conditions
Temperature
Altitude
Humidity
for indoor use only
5 - 35 °C
up to 2000 m
maximum relative humidity 80 % for temperatures up to
31°C decreasing linearly to 67 % relative humidity at 35
°C
Installation category II
Pollution degree 2
Dimensions (W x H x D) 400×660×360 mm
Weight 16.5 kg
3.3 Materials used
Table 3-5: Materials used for the K-350
Component Material designation Material code
Housing Polyurethane PUR / UL V0
Glass parts Borosilicate glass 3.3 DIN/ISO 3585
Steam generator isolation Ceramic fiber Multitherm 550
Steam generator housing Stainless steel 1.4301
Protective door Polymethyl methacrylate PMMA
Condenser cover Polymethyl methacrylate PMMA
Connecting stopper Hypalon CSM
NaOH tube Ethylene Propylene Dimonomer EPDM

4 Description of function
16 K-350 Operation Manual, Version G
4 Description of function
This chapter explains the basic principle of the instrument, shows how it is structured and gives a
functional description of the assemblies.
4.1 Instrument overview
3
1
2
4
5
6
a Splash protector
b Sample tube
c Protective door
dCondenser
eOperating panel
f Service door
Fig. 4.1: Instrument overview

4 Description of function
17 K-350 Operation Manual, Version G
4.2 Function principle
The Distillation Unit K-350 is suitable for determining nitrogen using the Kjeldahl (TKN; Total Kjeldahl
Nitrogen) and Devarda methods as well as for other distillations of steam-volatile substances (e.g. of
alcohol, SO2, volatile acids).
1
2
3
4
5
aSample tube
b Splash protector
c Condenser
d Distillate outlet tube
eReceiving vessel with receiver solution
Fig. 4.2: Function principle
Steam is introduced into the sample solution (in sample tube a) to drive out volatile components
(such as ammonia, alcohol, etc.). After condensation (in condenser c) the condensate is collected in
a receiver solution (in receiving vessel e).

4 Description of function
18 K-350 Operation Manual, Version G
4.3 Controls of the instrument
1
2
3
4
5
6
7
aSTOP: Stops a distillation or the addition of
reagent
b TIME display
c START: Starts a distillation
dTIME: Sets time in min:sec
eUP: Increases time and steam up
f DOWN: Decreases time and steam down
g REAGENT: Button that adds reagent (e.g.
water, sodium hydroxide solution)
Fig. 4.3: Controls of the instrument

5 Putting into operation
19 K-350 Operation Manual, Version G
5 Putting into operation
This chapter describes how the instrument is installed and gives instructions on initial startup.
NOTE
Inspect the instrument for damages during unpacking. If necessary, prepare a status report immedi-
ately to inform the postal company, railway company or transportation company.
Keep the original packaging for future transportation.
5.1 Installation site
Install the instrument on a clean, flat and stable base and place the storage tanks on the same level as
the instrument (not higher and not more than 1 m lower).
ATTENTION
To ensure the instrument safety do not place any object on top of it.
ATTENTION
For safety reasons, make sure that the distance between the instrument and another object or a wall
is at least 30 cm.
ATTENTION
For safety reasons do not place any containers, chemicals or other instruments behind the instru-
ment.
5.2 Electrical connections
Fig. 5.1: Electrical connections

5 Putting into operation
20 K-350 Operation Manual, Version G
ATTENTION
Make sure that the voltage on the socket corresponds to the voltage given on the type plate of the
instrument.
Always connect the instrument to an earthed socket. External connections and extension cables
must be provided with an earthed conductor lead (3-pole couplings, cable or plug equipment) as the
mains lead has a molded plug, thus avoiding risks due to inadvertent defective wiring.
The instrument cable must be well attainable at all times.
Make sure that no electric sparks form in the instrument or its surroundings as they might damage
the instrument.
5.3 Reagent and water connections
a
b
c
d
e
a H2O inlet (for steam generator) from tank
b NaOH input from tank
c Cooling water outlet
d Cooling water inlet
e Drain to waste
Fig. 5.2: Reagent and water connections
All pumps are self-priming, no overpressure is necessary at the tanks.
5.3.1 Cooling water connection
Secure the cooling water hose with a hose clamp on both the instrument and the water connection
side. The water pressure should be at a maximum of 4 bar. The built in valve reduces the water flow to
1.2 liters per minute.
The flanged screw coupling for the water connection has a standard screw thread of G ¾”.