An acidic water-based process was developed for the synthesis of anionic lignin copolymers with adjustable MW, thermal stability and solubility in water. The anionic lignin copolymer described herein comprises: a molecular weight of 5,000 to 7.4×10.sup.5 g/mol; and a charge density of −1 to −7.2 meq/g. The anionic lignin copolymers described herein which have a molecular weight range of 000-50,000 g/mol can be used as dispersants of negatively charged molecules or particles in numerous process or wastewater streams (e.g. concrete admixtures, gypsum slurries, textile dye) while such copolymers in a molecular weight range of 90,000-740,000 g/mole can be used as flocculants of positively charged molecules or particles in numerous process and wastewater streams including industrial and municipal systems and sludge dewatering in the textile dye, pulp & paper, mining and oil industries.

A process for co-depositing tailings streams and/or tailings products is provided comprising providing a tailings containment structure; and co-depositing at least two different tailings streams and/or tailings products into the tailings containment structure.

This invention refers to a method for preparing a chemical digester characterized by using organic and inorganic elements used for multiple purposes such as an accelerator in the decomposition of organic matter, as a water flocculant, as an organic soil fertilizer and as a means to eliminate the concentration of flies and other inserts in organic matter to decompose. The method comprises heating water in a reactor at a temperature of 38° C., adding a polysaccharide, an anti-thickener and an antifoam. The method then comprises the addition of two organic acids, one of them previously mixed in a second reactor and, finally, an inorganic acid until the mixture is homogenized. Optionally the method comprises the packaging of the mixture and the treatment of organic matter.

This invention refers to a method for preparing a chemical digester characterized by using organic and inorganic elements used for multiple purposes such as an accelerator in the decomposition of organic matter, as a water flocculant, as an organic soil fertilizer and as a means to eliminate the concentration of flies and other inserts in organic matter to decompose. The method comprises heating water in a reactor at a temperature of 38° C., adding a polysaccharide, an anti-thickener and an antifoam. The method then comprises the addition of two organic acids, one of them previously mixed in a second reactor and, finally, an inorganic acid until the mixture is homogenized. Optionally the method comprises the packaging of the mixture and the treatment of organic matter.

An apparatus for dewatering sludge comprises a tank having an internal space divided by a dividing wall into an intake chamber and an extract chamber, an intake pipe connected to the intake chamber by an intake valve, a discharge pipe connected to the extract chamber by a discharge valve, and a transfer pipe providing fluid communication between the intake chamber and the extract chamber. The transfer pipe has first opening near the bottom of the intake chamber, and a second opening near the top of the extract chamber. A pump selectively creates positive and negative pressure within the intake chamber. A screen is positioned within the extract chamber between the second opening of the transfer pipe and the discharge pipe.

An apparatus for dewatering sludge comprises a tank having an internal space divided by a dividing wall into an intake chamber and an extract chamber, an intake pipe connected to the intake chamber by an intake valve, a discharge pipe connected to the extract chamber by a discharge valve, and a transfer pipe providing fluid communication between the intake chamber and the extract chamber. The transfer pipe has first opening near the bottom of the intake chamber, and a second opening near the top of the extract chamber. A pump selectively creates positive and negative pressure within the intake chamber. A screen is positioned within the extract chamber between the second opening of the transfer pipe and the discharge pipe.

An anionic flocculant including: galactomannan; and a polysaccharide other than the galactomannan, wherein the anionic flocculant has a bulk density of 0.50 g/cm.sup.3 or more but 1.00 g/cm.sup.3 or less, the anionic flocculant has a particle diameter D.sub.50 of 250 μm or more but 850 μm or less, and the anionic flocculant has a particle diameter D.sub.10 of 150 μm or more.

An anionic flocculant including: galactomannan; and a polysaccharide other than the galactomannan, wherein the anionic flocculant has a bulk density of 0.50 g/cm.sup.3 or more but 1.00 g/cm.sup.3 or less, the anionic flocculant has a particle diameter D.sub.50 of 250 μm or more but 850 μm or less, and the anionic flocculant has a particle diameter D.sub.10 of 150 μm or more.

The present invention relates to a hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees (+/−0.1°). The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

The present invention relates to a hydrated crystalline form of 2-acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58°, 11.2°, 12.65°, 13.66°, 16.28°, 18.45°, 20°, 20.4°, 22.5°, 25.5°, 25.88°, 26.47°, 28.52°, 30.28°, 30.8°, 34.09°, 38.19°, 40.69°, 41.82°, 43.74°, 46.04° degrees (+/−0.1°). The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.