Fpinnovations

Lakehead University

Naceur Jemaa

Michael Paleologou

Talat Mahmood

Richard M Berry

Makhlouf Laleg

Xiao Zhang

Yaolin Zhang

Pedram Fatehi

Shoujuan Wang

Waleed Wafa Al Dajani

George Sacciadis

Jacquelyn Price

Adil Mazar

Brian O'Connor

A process for recovering alkali from power boiler ash is provided. The power boiler ash is first contacted with NaCOto produce a mixture containing settling and non-settling solid particles. A fraction of the settling particles is then separated from the mixture to produce a first clarified alkaline solution. The first clarified alkaline solution contains species such as NaOH and KOH depending upon the power boiler ash characteristics. The non-settling solid particles may optionally be further separated from the first clarified alkaline solution to obtain a second clarified alkaline solution. This process is also applicable for the extraction of alkali from other oxide/hydroxide containing materials.

Process to recover alkali from a metal oxide/hydroxide containing material

A water-based process was developed for the synthesis of aminated lignin copolymers with high MW, thermal stability and solubility in water over a wide range of p H values. The cationic lignin copolymer described herein comprises: a grafting ratio of (weight of cationic amine compound)/(weight of lignin) of 70 to 200% and a charge density of +1.4-3.0 meq/g. This cationic lignin copolymer can be used as a flocculant in numerous wastewater streams including municipal and industrial systems and sludge dewatering in the pulp & paper, mining and oil industries.

Process for producing cationic lignin copolymer under aqueous acid conditions

The present invention relates to a method of producing furfural and extracting lignin from a hemi-cellulosic biomass solution comprising a total quantity of C5 sugars, comprising the steps of heating the hemi-cellulosic biomass solution to a temperature of at least about 200&#xb0; C.; acidifying the hemi-cellulosic biomass solution with acid to produce the furfural in vapor phase; and condensing the furfural to recover furfural in solution, wherein the furfural is produced at a total molar yield of at least 70% of moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution. Low molecular weight lignin can also be recovered from the hemi-cellulosic biomass solution prior to furfural production by membrane concentration, acidification, coagulation and filtration.

Lignin recovery and furfural production from prehydrolysate streams

Acid hydrolysis of biomass is an important step for releasing the component sugars before converting them to fuels and/or biochemicals. During such a process, a significant amount of mineral acid, such as sulfuric acid, is used. In most cases, the residual acid is neutralized with lime before the sugar conversion step. By doing so, a waste calcium sulphate stream is generated and sent to disposal. The efficient separation of acid from the sugars would allow the recycle of the acid and make the entire process more economically viable. We found that a resin bed packed with an acid retardation resin can be used to achieve an efficient separation (i.e. 98.5% recovery of the acid) of the sulfuric acid from the sugars. The resin bed can be simply regenerated with water.

Method for recovering an acid from acid/sugar solutions

The present invention describes a process and system of producing methanol from methanol condensates. In a preferred embodiment the condensates are biomethanol condensates from chemical pulp mills and various waste sources used to produce a purified biomethanol. Pulp condensates are rich in methanol and contain many other contaminants. Presently, most chemical pulp mills, such as Kraft pulp mills use steam stripping to remove and concentrate the methanol and burn the methanol onsite along with the contaminants. A combination of treatments that include air stripping, steam stripping, distillation and reverse osmosis is described to obtain purified biomethanol suitable for sale or use on site.

Method for producing bio-methanol at pulp mills

During nanocrystalline cellulose (NCC) production, a considerable amount of sulphuric acid is used. After the separation of the NCC, the remaining solution contains sugars and residual sulphuric acid. The sugars are in the monomeric and oligomeric forms. To reduce the cost of NCC production and to produce other added-value products, the spent acid stream can be fractionated into sugar oligomers, sugar monomers, and acid. The acid can be recycled to the NCC manufacturing process after concentration. The sugar monomers and sugar oligomers can be used for the manufacturing of other valuable chemicals. Membrane nanofiltration can be used to achieve this objective. A polymeric membrane with a molecular weight cut-off in the range of 200 Dalton was employed. Using this approach, the majority of the acid was recovered in the permeate while the sugars were concentrated in a smaller stream. The sugar level in the separated acid/permeate stream was only about 3% of the original concentration. A second membrane filtration stage can be used to separate the monomeric from the oligomeric sugars. The two sugar streams can be employed in different applications to produce value-added products.

Fractionation of a waste liquor stream from nanocrystalline cellulose production

A method and apparatus for the treatment of pulp mill condensates is described. A hollow fiber contactor, incorporating a hydrophobic membrane, was used to remove several undesirable compounds from pulp mill condensates. For example, TRS compounds and SOwere efficiently stripped from kraft and sulphite mill evaporator condensates, respectively. Methanol was also removed from kraft mill condensates but at a lower efficiency than TRS. Furthermore, other undesirable compounds found in condensates of pulp mills that contribute to the BOD and COD loading to effluent treatment systems were also removed. These contactors are cost effective since air, vacuum or a suitable solvent or scrubbing solution can be used as the stripping medium to drive off through the membrane several undesirable compounds from the feed solution. The undesirable compounds removed can thus be burned in the recovery boiler, lime kiln or a dedicated boiler.

Process for treating pulp mill condenstates using a hollow fiber contactor

Steam stripper off gas from chemical pulp mills, for example kraft or sulphite pulp mills is rich in methanol and totally reduced sulphur (TRS) compounds. This gaseous stream is usually burned to avoid further handling of this TRS-rich, odorous stream. We found that once this gaseous stream is condensed, it can be used as a reducing agent in the chlorine dioxide generator, in place of purchased methanol. Surprisingly, we found that, in addition to the methanol component, the TRS components act as reducing agents during the production of chlorine dioxide or, at the very least, do not consume chlorine dioxide. The use of this stream in the ClOgenerator will allow pulp mills to reduce or eliminate the consumption of purchased methanol while providing a new approach to deal with TRS compounds in the chlorine dioxide generator rather than employing a dedicated TRS incinerator or any other combustion device.

Growing community of inventors

Pointe-Claire, Canada

Naceur Jemaa