Sequoia is the sole manufacturer
of the LISST series laser particle size analyzers. The array of
instruments originated with applications in the marine environment, but
now includes diverse fields such as stream-gaging, paper emulsifier optimzation, airborne cloud dropet measurements and others still in development. Some of these instruments
deliver the optical volume scattering function
(VSF) of interest to optical oceanographers. All LISST instruments are compliant with the ISO-13320-1 standard for laser diffraction.
The LISST series includes submersible and non-submersible instruments. All
employ the small-angle forward scattering principle, also called low-angle laser
scattering or laser diffraction.
The submersible series includes:
Of these, the LISST-100X is our workhorse. It delivers the
size distribution of suspended sediments in 32 logarithmically spaced size
classes. Different models of this instrument cover different range of sizes. These instruments can be used as laboratory instruments, with
is an extended version of the LISST-100X, with an added Settling Tube (ST stands
for Settling Tube). This instrument is designed to perform submerged settling
experiments to obtain settling velocities of 8 size classes. With the settling
column removed, the LISST-STX may be used as a -100X, but with less than optimal
flow through the sample volume.
The LISST-25X is a patented derivative product. It
delivers the suspended sediment concentration and mean size in two size classes
(2.5-63 and 63-500 microns).
All of the above submersible instruments
incorporate a depth sensor. They are powered by internal batteries and store
The LISST-SL is
an isokinetic version of the LISST-100X developed for river sediment monitoring.
It senses river velocity and adjusts intake velocity to match. Optics and
electronics are enclosed. Data are stored on a bridge-top Topside box.
Field and Portable Particle/Sediment Size Analyzers
- The LISST-Portable
The LISST-Portable is a portable field or laboratory device for particle size and
concentration measurements. It is battery operated, easily
transported (car, airplane, train, mail), is equipped with a touch panel display for easy programming and data display. No computer is necessary except for data offload. Data are processed immediately upon collection and stored on
board - no post-processing is necessary.
The LISST-StreamSide is meant for use in shallow streams or
rivers and is designed for applications where bio-fouling is
an issue, or streams are too shallow for instrument submergence,
or there exist concerns regarding the safety of the equipment from
flowing debris or due to vandalism. The instrument is designed to be
enclosed in a shed, wth power provided. A pump is inserted in the
stream to deliver water. This device displays the size distribution in
real time on a plasma display and stores processed data for subsequent download.
Deliveries are planned for mid-2007.
The LISST-Infinite is designed for measuring very high concentrations
of sediment, such as occur in rivers or in run-of-river Hydro power plants. The instrument is placed in a
shed and again, water is pumped through it. A clean water source is
required for dilution. The instrument performas dilutions if needed. In this manner particle size and concentration can be measured in suspensions of up to 250 g/l.
For more information on these instruments, please click on the links at top of this page, or contact us.
(Emulisifer Optimizer) is an in-line process control tool. It is designed to measure particles
in the 0.3-60 microns( nominal size). This device employs our standard
forward low-angle scattering technology with the reverse Fourier
geometry. The instrument displays the size distribution on a
panel-mounted plasma display, and sends the data to a remote desk for
display and storage. Deliveries are planned for mid-2007.
|LISST-SOP 5.0 Released |
|LISST-SOP 5.0 for LISST-100X and LISST-Deep released! |
-Inversion of randomly shaped particles
-Command line batch processing
-Improved serial port communication
|Experts Conference on Turbine Abrasion |
Le Meridien Hotel, New Delhi, India, 31 May 2013
HydroVision International 2013
Denver, CO, 23-26 July 2013, booth 337
Seattle, WA, 12-15 August, booth 224
Oceanology International CHINA
Shanghai, China, 3-5 September 2013
35th IAHR World Congress
Chengdu, China, 8-13 September 2013