White Liquor Oxidizer

Quantum Q-OWL Process

[ Illustrating Graphic ]
Q-OWL In Place of NaOH

Mills that have tightened up their sulfur emissions and use 100% CLO2 to meet environmental regulations can have either a surplus of white liquor or a caustic imbalance. Using Q-OWL oxidized white liquor as an alkaline source in O2 delignification, extraction stages and SO2 scrubbing can:

  1. Reduce NaOH purchases
  2. Provide a sulfur and trace metal purge

The Process (Patent Pending)

The Quantum Q-OWL process takes white liquor directly from the clarifier into a break-seal tank, pumps it into the X-O ThermTM reactor (patent pending) where it is mixed with pressurized oxygen, then to a gas/liquid separator where the oxidized white liquor is piped to the process and the gas (a small amount of the unreacted oxygen and dissolved gases purged from the white liquor) is vented back to the receiving tank. A heat exchanger is optional depending upon the use of the oxidized white liquor.

Automated Control

The Q-OWL process is completely automated. It can be controlled from a control room either from its own control panel or as a part of a distributed control system.

Economic Operation

The exothermic heat of reaction generated in the X-O-Therm reactor is recoverable either by use of the hot oxidized white liquor or via the optional heat exchanger. This energy savings reduces the cost of oxygen and power by as much as 40% and provides the superior quality of the Q-OWL liquor at a cost competitive with partially oxidized white liquor from either air or oxygen.

Compact Size

With a reaction rate 16 times faster than a stirred tank, the reactor and the entier Q-OWL process is much smaller than an equivalent system based on a stirred tank. A 50 gpm process occupies a floor space of approximately 15' x 20' x 10'H. The compact size also allows the Q-OWL process to be placed where needed i.e. the pulp mill for O2 delignification, the bleach plant for extraction stage use or the chemical prep area for scrubbing recovery boiler gases.

Quick & Easy Installation

The Q-OWL process is skid mounted requiring minimal assembly at the mill site and ready for mounting on a foundation. Final installation requires only electricity, oxygen, feed and takaway piping to the battery limits, and process control installation. Metallurgy is 304 S.S. throughout.

Quality of Q-OWL Liquor

In order to be used as an alkaline source in bleaching stages, oxidized white liquor must not react or interfere with the beaching chemicals. Studies have demonstrated that Q-OWL can be used in any bleaching stage, including peroxide stages, and produce pulp of at least comparable quality to that obtained using NaOH. Q-OWL does not contain any Na2S which could form toxic H2S if filtrate were carried over to an acid stage.

Typical Analysis

Oxidized white liquor used in the following laboratory work was produced in the Q-OWL pilot plant using mill white liquor direct from the clarifier.

Concentrations (g/L as Na2O)
NaOH Na2S Na2S2O3 Na2SO3 Na2SO4
WL 58.9 30.8 1.61 1.50 3.54
Q-OWL 62.0 0 2.81 1.70 30.5
Note the Q-OWL increase in NaOH is a result of the oxidation reaction.

Q-OWL liquor replaces NaOH in all bleaching stages including peroxide stages.

Q-OWL in O2 Delignification

Starting Pulp: Kraft Hardwood
Br = 27.4 Vis = 27.5 Kappa = 14.4
Conditions: 2.5% NaOH equivalent
100°C; 110 psig O2; 0.1% MgSO4;

Caustic Source NaOH WL Q-OWL
pH 12.5 12.7 12.6
GE Br. 46.6 44.1 46.4
Viscosity 18.5 16.8 18.1
Kappa 8.4 8.8 8.3

Starting Pulp: Kraft Hardwood
Br = 28.2 Vis = 31.4 Kappa = 29.1
Conditions: 2.5% NaOH equivalent
100°C; 110 psig O2; 0.1% MgSO4;

Caustic Source NaOH WL Q-OWL
pH 11.8 11.7 11.5
GE Br. 41.5 44.4 43.4
Viscosity 16.1 13.2 14.7
Kappa 12.1 11.1 11.1

Q-OWL in Bleaching Stages

The alkali source listed for each sequence was used in each stage of that sequence which called for NaOH (i.e. the O, Eop, E and P stages).


Pulp Type Kraft SW
Sequence ODEOPDED
Alkali NaOH WL Q-OWL
GE Br. 89.0 88.0 89.1
Viscosity 16.9 15.6 18.1

Pulp Type Kraft HW
Sequence DEOPD
Alkali NaOH WL Q-OWL
GE Br. 88.4 85.8 89.1
Viscosity 20.7 24.4 24.4

Pulp Type Kraft HW
Sequence ODEOPP
Alkali NaOH WL Q-OWL
GE Br. 85.1 83.9 85.2
Viscosity 12.3 12.2 12.7

Q-OWL in SO2 Scrubbing.
Scrubbing Outgoing Flue Gas
Liquid SO2 (mg/m3) H2S (mg/m3)
NaOH 100-300 0 to 6
W.L. 100-300 30 to 100
Q-OWL Type 80-320 0 to 7


PLANT TRIAL DEMONSTRATION

To Answer the Question - How will the Q-OWL process work

With my white liquor?

In my pulp mill?

In my bleaching stages?

In my SO2 Scrubber?

There is only one answer - a plant trial!

[ Picture of Plant Trial Demonstrator ]

A nominal 50 gallon per minute Q-Owl White Liquor oxidizer process mounted on a 8' x 25' trailer fully operational and ready for a plant trial. Similar to a commercial unit the demonstrator requires electricity, oxygen, white liquor feed and take-away piping and depending upon the application, cooling water. The process is operated from the trailer bed and controlled by its own console which can be located up to 500 ft. from the trailer allowing ti to be placed in a central control room.



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2634 S. Arlington Rd.
Akron,OH 44319, USA
Email: dgalluch@quantumtechn.com
Phone: (330)645-2762
Fax: (330)425-2768

Homedgalluch@quantumtechn.comLab EquipmentGas/Liquid Reactor