New diode laser spectrometer with optimum combustion control

Yoko­gawa Elec­tric Cor­po­ra­tion plans to launch its new­ly devel­oped TDLS8200 tun­able diode laser spec­trom­e­ter as part of its OpreX™ Ana­lyz­ers prod­uct fam­i­ly on May 6, 2021. The new prod­uct fea­tures the same low instal­la­tion cost, high mea­sure­ment sta­bil­i­ty and high reli­a­bil­i­ty as its pre­de­ces­sor, the TDLS8100, and can simul­ta­ne­ous­ly mea­sure oxy­gen, car­bon monox­ide and methane gas con­cen­tra­tions direct­ly and at high speed.

Development background

Excess air sup­plied dur­ing com­bus­tion con­trol in heat­ing fur­naces absorbs heat in the fur­nace before exit­ing through the exhaust stack. This not only leads to heat loss, but can also gen­er­ate large amounts of nitro­gen oxides and sul­fur oxides, which are a major cause of air pol­lu­tion. On the oth­er hand, if there is insuf­fi­cient air sup­ply, com­plete com­bus­tion does not occur, result­ing in ener­gy loss­es, emis­sion of car­bon monox­ide and black smoke, and resid­ual methane. Car­bon monox­ide and methane are flam­ma­ble gas­es that can eas­i­ly form an explo­sive mix­ture with air if they accu­mu­late in a fur­nace. There­fore, in oil and gas, elec­tric pow­er, iron and steel, petro­chem­i­cal, and ceram­ic plants, the con­cen­tra­tions of oxy­gen, car­bon monox­ide, and methane in fur­naces must be mon­i­tored to ensure an effi­cient, envi­ron­men­tal­ly friend­ly, and safe com­bus­tion process.

Features

1. Effi­cient com­bus­tion and high safe­ty through sta­ble, simul­ta­ne­ous mea­sure­ment of oxy­gen, car­bon monox­ide and methane.
The main fea­ture is the dual laser light source and optics, which enables simul­ta­ne­ous mea­sure­ment of oxy­gen, car­bon monox­ide and methane con­cen­tra­tions for effi­cient com­bus­tion con­trol. The direct mea­sure­ment sys­tem is based on the use of lasers, which are eas­i­er to main­tain than con­ven­tion­al sam­pling sys­tems and more robust than cat­a­lyst-based sen­sors. This pro­vides sta­ble, simul­ta­ne­ous and loss­less mea­sure­ment of oxy­gen and car­bon monox­ide concentrations.
 
2. Easy replace­ment of sam­pling systems
The new prod­uct is an easy-to-install diode laser spec­trom­e­ter with in-situ probe. Exist­ing sam­pling sys­tems can be quick­ly and eas­i­ly replaced, which can be installed at the same port as the pre­vi­ous instru­ment. Since sam­ple col­lec­tion or prepa­ra­tion sys­tems are unnec­es­sary, lit­tle floor space is required.
 
3. Planned sec­ond ver­sion for mea­sure­ments in envi­ron­ments with tem­per­a­tures up to 850°C.
Avail­able May 6, 2021, the spec­trom­e­ter is designed for high tem­per­a­tures of 600°C, mak­ing it ide­al for use in boil­ers and exhaust ducts. A sec­ond ver­sion of the TDLS8200 for mea­sure­ments at tem­per­a­tures up to 850℃, such as when used in heat­ing fur­naces, is sched­uled for release lat­er this year.

Laser-based gas analyzers from Yokogawa

Yoko­gawa’s laser-based gas ana­lyz­ers oper­ate on the prin­ci­ple of tun­able diode laser spec­troscopy (TDLS) for con­cen­tra­tion deter­mi­na­tion in gas­es. They offer best-in-class real-time per­for­mance because they are installed on chan­nels and do not require a sam­pling sys­tem, so they can mea­sure con­cen­tra­tions direct­ly and at high speed. They use a spec­tral domain method that cal­cu­lates gas con­cen­tra­tion from the area in a light absorp­tion dis­tri­b­u­tion pat­tern — enabling accu­rate and sta­ble con­cen­tra­tion mea­sure­ment even in an envi­ron­ment with tem­per­a­ture and/or pres­sure vari­a­tions or in the pres­ence of oth­er types of gas­es or large amounts of dust.
Since their launch in 2008, Yoko­gawa’s laser gas ana­lyz­ers have gained world­wide accep­tance for their high reli­a­bil­i­ty and per­for­mance in even the most chal­leng­ing envi­ron­ments. Pre­vi­ous­ly, Yoko­gawa had two mod­els in its line­up: the TDLS8000 and the TDLS8100. The for­mer is equipped with a sep­a­rate laser light source and detec­tor and is suit­able for con­cen­tra­tion mea­sure­ment in high-tem­per­a­ture and high-pres­sure gas­es, even with high dust lev­els. The TDLS8100 is capa­ble of mea­sur­ing the con­cen­tra­tion of gas­es whose flow rate ranges from 1 to 30 meters per sec­ond. With the addi­tion of a third mod­el to this series, simul­ta­ne­ous mea­sure­ment of mul­ti­ple gas types is now possible.