A defoamer or anti-foam formulation and a process for preparing the same. The process includes in a first step, preparing branched organopolysiloxanes (A) by irradiating organopolysiloxanes (X) of the formula (1)

R.sup.1.sub.3-a(R.sup.2O).sub.aSi—[OSiR.sup.3.sub.2].sub.n—OSi(OR.sup.2).sub.aR.sup.1.sub.3-a   (1).

Where with high-energy radiation, the viscosity of the organopolysiloxanes (A) is at least 40% higher than the viscosity of the organopolysiloxanes (X). In a second step, the branched organopolysiloxanes (A) are treated with a filler (B) which is selected from precipitated and/or fumed silicas, and organopolysiloxane resins (C).

There is provided a defoaming agent having excellent defoaming persistence. The defoaming agent includes; hydrophobic silica having a hydrophobicity (M.sub.X) of 50 to 85, and a rate of change (M.sub.Y/M.sub.X) of a hydrophobicity (M.sub.Y) after immersion for 1 hour in a methanol/ion-exchange aqueous solution (volume ratio of 80/20) of sodium hydroxide with a pH of 13 at 25° C. to the hydrophobicity (M.sub.X) of 0.8 to 1.0; and at least one kind of liquid selected from the group consisting of a hydrocarbon oil, a non-reactive silicone oil and a polyoxyalkylene compound.

The invention herein disclosed and claimed is a process for refining fiber from lignocellulosic biomass. The process provides refined fiber and agriculturally amenable co-products, with a virtually waste-free systems design.

The present invention is related to a method for: reducing metals content in a Kraft pulping process comprising adding magnesium to a black liquor that is returned to the pulping operation; reducing aluminum content in a pulping process by adding magnesium to the black liquor to provide a green liquor having a specific molar ratio of magnesium:aluminum; producing or treating a green liquor having a specific molar ratio of magnesium:aluminum by adding magnesium to the black, weak black, strong black liqueurs; and producing hydrotalcite by the addition of at least 0.04-5.0 mols of magnesium:aluminum present at the weak black, strong black liqueurs, or a combination thereof. It is also provided a pulp mill comprising a digester (1), a washer (2), an optionally pulp bleaching, a weak black liquor concentrator (4), among other parts.

The invention relates to a method for clarification of raw green liquor in a sedimentation tank. According to the invention is a part of dregs separated in the sedimentation tank recirculated back into the inflow of raw green liquor, and preferably after passing the dregs through at least one turbulence generator (30, 31) that could break up larger dregs particles into smaller dregs particles, and thus create larger total surface on the dregs particles, improving sedimentation rate in the sedimentation tank. In a preferred embodiment is the recirculated dregs added into the flow of raw green liquor before a flocculant is added into the flow of raw green liquor and mixed recirculated dregs.

The invention herein disclosed and claimed is a process for refining fiber from lignocellulosic biomass. The process provides refined fiber and agriculturally amenable co-products, with a virtually waste-free systems design.

To promote anaerobic digestion and delay calcification, one or more signal molecules are used to regulate the microenvironment of anaerobic granular sludge. In the process of anaerobic granular sludge treatment of papermaking wastewater, AHLs (N-acyl Hyperserine Lactones) are added to papermaking wastewater before the papermaking wastewater enters the anaerobic reactor. This may occur when the proportion of microorganism in anaerobic granular sludge VSS/TSS is less than 0.6. Further, the addition of the one or more signal molecules changes the community structure of the bacteria and methanogens, promoting anaerobic digestion and delay calcification. Additionally, the microenvironment of granular sludge is regulated by adding one or more micro-signal molecules to improve the number of bacteria susceptible to calcification, improve the anaerobic digestion rate of sludge that has not been calcified, and delay the calcification rate.

The invention relates to a method for clarification of raw green liquor in a sedimentation tank. According to the invention is a part of dregs separated in the sedimentation tank recirculated back into the inflow of raw green liquor, and preferably after passing the dregs through at least one turbulence generator (30, 31) that could break up larger dregs particles into smaller dregs particles, and thus create larger total surface on the dregs particles, improving sedimentation rate in the sedimentation tank. In a preferred embodiment is the recirculated dregs added into the flow of raw green liquor before a flocculant is added into the flow of raw green liquor and mixed recirculated dregs.

The invention relates methods and processes for the separation and refining of lignin from spent cooking liquor, called black liquor, present in industrial chemical plants, and compositions thereof. A process is provided for separating black liquor into at least two, three, or four streams selected from: (i) a gaseous stream comprising volatile sulfur compounds; (ii) a lignin-comprising stream produced by extracting lignin into a limited solubility solvent S1; (iii) a salt stream, comprising solid sodium and sulfate salts; and (iv) a salt-depleted and lignin-depleted aqueous stream comprising hydrocarbons.

The spent liquor (SL) of a thermomechanical pulping (TMP) process introduces a high load to the wastewater system of this process. To reduce this load, fly ash from a biomass boiler is used and the application of fly ash improves the performance of biological process. Three different alternatives are introduced to apply fly ash to treat spent liquor.