Nitrogen Analyzer


NDA 701 is a powerful Dumas Nitrogen Analyzer, according to the Dumas combustion analysis, able to hold up to 4 discs of 30 positions each. Performing precise analysis in a flash, it is the best solution for high productivity and offers unique benefits, being totally unsupervised. This means that the NDA does not need to be controlled during its work and is able to process samples 24/7. Also under the environmental aspect it is a great solution: minimum wastes and residues are produced and the life of consumables is optimized by the software (remaining customizable for any need). Saving on consumables means saving money: with a consciousness lab managing, the cost per analysis will be incredibly low.

NDA 701 is entirely controlled via PC through the intuitive DUMASoft™ Software. The several pre-installed methods and the numerous calibration curves that can be stored, increase the efficiency of the instrument. The software accepts weight values directly from the balance. Data management appears clear and detailed, thanks to the final reports and the graph. The analyses can be recalled by a database and can be saved in different format (according to LIMS) on the PC, exported as test reports or printed. NDA 701 offers a very low detection limit (0.003 mg N) and a good RSD% (<0.5% with EDTA standard).

Performance is ensured when NDA 701 works with original VELP consumables.

Supplied with

All the accessories for maintenance, connections, reactors and sample preparation are supplied with the instrument.

DKL - The fully automatic Kjeldahl Digestion Series

The fully auto DKL Digestion System is composed of an Aluminum Heating Block offering excellent temperature homogeneity, precision and accuracy; an Auto Lift and an Auto Suction Cap and is supplied as a complete package including test tubes, Sample Rack and Drip Tray. The DKL incorporates VELP’s revolutionary TEMS™ technology for unprecedented Savings in terms of Time, Energy - as much as 35%, Money and Space. High-Tech but Simple to use, a Microprocessor controls the block temperature whilst an electronic Auto-Calibration System ensures excellent reliability and repeatability of analysis. A Practical Interface with LCD Graphic Display allows access to all the data including the Multi-Language Library and the 54 Programs available, 24 of which are user-programmable. The Digestion Unit is Extremely Compact with a narrow footprint for optimum use of space on the lab bench. In compliance with GLP (Good Laboratory Practice), data can be printed or stored in a PC.


  • Control System: Microprocessor with LCD Graphic Display.
  • Temperature Range: Ambient to 450 °C / 842 °F.
  • Temperature Stability: ± 0.5 °C.
  • Temperature Precision: ± 0.5 °C.
  • Set Temperature: Digital Readout in °C, °F or K.
  • Temperature Calibration: Automatic.
  • Program Library: 54 Program library, including 24 user-programmable memories.
  • Temperature Ramping: Upto 4 ramps per program.
  • Time Selection: 1 to 999 Minutes - 1 Minute Steps.
  • Countdown: Digital Readout.
  • Languages: Multiple.
  • Run Completed Alert: Visual and Acoustic Signal.
  • Damaged Temperature Probe: Automatic Detection and Alarm Message.
  • Complies to AOAC, ISO, EPA, DIN.

Rapid Heating
54 - programmes
Unsupervised Digestion

Specifications Sheet


The work horse from the Velp, DK series is in use in numerous labs around the World. The DK series combines reliability with economy and provides all modern requirements of Kjeldahl Digestion.


  • Construction : Epoxy painted stainless steel.
  • Display: 2-line LCD display.
  • Interfaces: RS232 for PC connectivity.
  • Temperature values: °C or °F.
  • Temperature range : Ambient +5 to 450 °C / 842 °F.
  • Temperature Accuracy: ± 0.5%.
  • Heating Rate: Ambient to 420oC in 30 Min.
  • Selectable programs: 20 with 4 ramps for each program.
  • Timer : 1 to 999 minutes.
  • Languages: 6 Languages.
  • Calibration : Auto calibration of heating block.

Specifications Sheet

Water Aspiration Vacuum Pump

The JP is a re-circulating water pump with two different timed mode selection. This ensures optimum aspiration depending on the digestion phases and the number of samples in the digester connected the pump.

The premium quality of the materials used makes the instrument extremely quiet, resistant and high performing (up to 35 l/min).

SMS Scrubber System

The SMS Scrubber is designed to neutralize corrosive and toxic fumes produced during oxidative mineralization or similar processes.

The configuration is based on two stages :

  • condensation
  • neutralization

Thanks to the elevated surface of contact between gas and liquid, the SMS provides effective cleaning of the fumes, preventing their hazardous emission into the laboratory and environment.


VELP Scientifica distillation units are the ideal solution for performing analyses concerning different applications such as determining ammoniacal nitrogen, protein content , nitrogen (Kjeldahl or direct alkaline distillation), nitric nitrogen (after reduction), phenols, volatile fatty acids, cyanides, alcohol content and Devarda nitrogen determination.

VELP Scientifica offers a wide choice with its 4-model series for performing efficient and reliable steam distillations, according to the different needs of the users.

All the units support the most advanced technology, consisting in a unique patented steam generator and an outstanding efficient patent pending titanium condenser that are wisely combined with a technopolymer splash head.

Designed with a strong and chemical-resistant structure made of technopolymer, UDK Series has been designed to last in time and to perform reliable analysis for many years.

Different safety features have been assembled on the units to improve the safety level of our users :

  • Safety lever avoids contact with soiled surfaces.
  • Protective door with sensor shields test tube & prevents spills; completely closed.
  • Service door + automatic electrical shutdown for extraordinary maintenance.
  • Cooling water flow-rate detector activates low flow-rate warning signal.
  • Test tube sensor ensures the presence of the test tube.
  • Drip tray collects any drops.



All models incorporates VELP revolutionary TEMS™ technology for unprecedented time, energy, money & space and works in accordance with official regulations including AOAC, EPA, DIN & ISO

UDK 129

The UDK 129 Distillation Unit is the entry-level solution for your analyses concerning different applications such as determining ammoniacal nitrogen, protein nitrogen, (Kjeldahl or direct alkaline distillation), nitric nitrogen (after reduction), phenols, volatile fatty acids, Cyanides, alcohol content and Devarda Nitrogen determination.

The UDK 129 runs automatically, after setting sodium hydroxide addition and distillation time using the LCD display in order to get reliable and accurate results. The high-precision pumps ensure constant accurate dosing of reagents and the cooling water is automatically stopped during pauses, thus cutting down on its consumption.


The UDK 139 runs automatically, after setting distillation time, Water and sodium hydroxide addition and steam generation Output level between 10 and 100℅ using the innovative 3.5”color Touch screen. The high-precision pumps ensure constant accurate dosing of reagents. Accessing the 10 customizable methods available in different languages Is simple and intuitive. The new UDK 139 incorporates a considerably high level of technology, With the VELP patented steam generator that offers high performance, safety (no pressure inside) And maintenance-free. Another unique VELP component is the titanium condenser offering Reduced water consumption, ensuring that distillate temperature always remains below the threshold value.


The UDK 149 operates automatically, after setting on the multi-function 3.5”color touch screen water, Boric acid and sodium hydroxide addition, distillation time and the steam generation output, Level between 10 and 100℅. Different automatic titrator model can be connected to the UDK 149 for the direct output of the final result and offering choice and Versatility to the user.

The high precision pumps ensure constant dosing of reagents. All the parameters concerning distillation and titration phase are easily programmable. Simple, time-saving and intuitive operation is assured by direct access to the 20 customizable methods available in 6 different languages(additional languages are also available).The UDK149 offers powerful archiving features. The interface enable results to be downloaded to a pen drive or directly to a PC. The .xls format permits operators to use well-known Software for extracting reports with maximum flexibility.


The UDK 159 run Automatically, after setting distillation time and water, boric acid and sodium hydroxide addition, the steam generation output from 10 to 100℅ using the innovative 6” Color touch screen. The high-precision pump and burette ensure constant accurate dosing of reagent and with the integrated colorimetric titrator (AOAC recommended)you will have reliable results concerning your determinations. Automatic titration vessel cleaning provides significant advantages including reducing maintenance to a minimum. A 54 Program library (30-predefined+24 Customizable)cover the needs of any laboratory and the reporting system is comprehensive.


The UDK 169 Distillation & Titration System is designed to perform nitrogen and protein determination according to the Kjeldahl Method (TKN) in the Food & Feed industries and several other applications in environmental control (phenols, nitrogen in water, sludge, soil and lubricant) and also in the chemical and pharmaceutical industries after having digested the sample accurately.

The combination of UDK 169 and the AutoKjelsampler offers complete automation: load up to 24 x250 ml (Ø 42 mm) or 21 x400 ml (Ø 52 mm) test tubes and you will get accurate and reliable results, unattended.

Sample tubes are taken from the carousel and fed directly into the UDK 169 for further processing.

Compact and impressive, it eliminates unnecessary efforts and time. Upgrade your analyzer at any time, since UDK 169 can be used stand-alone, or it can be combined with the AutoKjel autosampler, to drastically increase the productivity.

Automatic colorimetric titration (AOAC recommended) is followed by automatic titration vessel cleaning. The multitasking software enables the operator to set all the parameters for a fully automatic control of the distillation and titration processes. UDK distillation & titration system offers instantaneous reporting, powerful data handling with on-board archive for data storage, balance data input, output to PC, pen drive, printer in a common format, via Ethernet and USB.

RS232 port is used for the connection with AutoKjel autosampler.

Maximum Productivity, Full Automation

The UDK 169 & AutoKjel system is developed for continuous operation, providing the maximum sample throughput and data processing automation.

You will be supported by proven reliability, ease of use and time saving for safer and simpler activities.

Upgrade your analyzer at any time, since UDK 169 can be used stand-alone, or it can be combined with the AutoKjel autosampler, to drastically increase the productivity.

Unmatched Flexibility

The engineering ensures high independence and flexibility, since the AutoKjel can stand a carousel of two dimensions, with 24-pos. of 250 ml or 21-pos. of 400 ml.

Sample tubes are taken from the carousel and fed directly into UDK 169 for further processing and reliable results.

Colorimetric Titration

The automatic Kjeldahl analyzer UDK 169 is the top of the range model offering the ultimate in capabilities including colorimetric titration, as recommended by the AOAC.

The UDK 169 colorimetric titration is

  • calibration-free.
  • maintenance-free.
  • not sensitive to volume and external light.
  • automated, for maximum simplicity and security.

UDK 169, the most reliable titration system in the Kjeldahl analysis!