A method for removing calcium ions from high concentration organic wastewater is provided. The method comprises the steps of: (1) introducing high concentration organic wastewater containing Ca.sup.2+, inorganic carbon and a seed crystal into a reactor with a molar ratio of Ca.sup.2+ to inorganic carbon of 1:(3.2-6.2); (2) adjusting the hydrogen ion activity α(H.sup.+) and ionic strength of the solution in the reactor; (3) sequentially stirring and precipitating in the reactor to convert Ca.sup.2+ in the high concentration organic wastewater into calcium carbonate which is then precipitated for calcium removal.

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.

One aspect of the present invention provides an estimation device for estimating the degree of pitch production in a water system, or the degree of hindrance due to pitch. This estimation device comprises a turbidity information acquisition unit, a relationship model information acquisition unit, and an estimation unit. The turbidity information acquisition unit acquires turbidity information including the turbidity of the water system. The relationship model information acquisition unit acquires relationship model information which was generated in advance, and which indicates the relationship between the degree of pitch production or the degree of hindrance due to pitch, and turbidity. The estimation unit estimates the degree of pitch production or the degree of hindrance due to pitch, on the basis of the turbidity information and the relationship model information.

The present invention relates to a method and to a device for continuous cleaning of process water circulating in a device for treating waste paper. The process water is supplied, from a unit of the device, to an anaerobic reactor comprising a gas separator, and the cleaned process water is returned back to a unit of the device, wherein this unit is selected from: a pulper; screening device; dewatering unit; oxidation/reduction unit; centrifugal screening device; fine screening device; paper-machine mould section; paper-machine press section; reject treatment unit; fibre recovery unit; and drying section; wherein the content of inorganic solids in the reactor is measured and, if this content exceeds a pre-set limit value, process water from the reactor is continuously fed to a solid-liquid separator for separation into a fraction that is depleted of inorganic solids and a fraction that is enriched with inorganic solids, wherein the fraction that is depleted of inorganic solids is returned to the anaerobic reactor and the fraction that is enriched with inorganic solids is conveyed away out of the device, until the content of inorganic solids in the process water is less than the limit value.

Provided is a microbial fuel cell including a cathode and an anode, wherein the cathode includes a waterproof gas diffusion layer including a siloxane and a catalyst layer including a binder, wherein a surface of the gas diffusion layer opposite the catalyst layer contacts air, and the anode includes electrogenic bacteria. Also provided is a method for making a microbial fuel cell, including fabricating a cathode, wherein fabricating includes disposing a siloxane solution onto a surface of a substrate, wherein the siloxane solution includes a siloxane and a solvent, drying the siloxane solution to form a waterproof gas diffusion layer, and placing the gas diffusion layer on a catalyst layer including a binder, and facing an anode with the cathode whereby the gas diffusion layer faces away from the anode and contacts air.

A filtration apparatus and methods of installing, using, and retracting the same. A filtration apparatus includes a compression gland, a ball valve, and a filter pipe. A distal portion of the filter pipe has one or more filtration holes. The filtration apparatus may be installed in a process pipe and the distal portion of the filter pipe may be disposed within the process pipe. The filter pipe can be easily retracted from the process pipe without interruption of the industrial process. The filtration apparatus can be automatically cleaned by compressed air or water.

In some embodiments, a method may include treating pulp in pulp and paper mills. The methods may include providing a peracetate oxidant solution and generating a reactive oxygen species. The peracetate solution may include peracetate anions and a peracid. In some embodiments, the peracetate solution may include a pH from about pH 10 to about pH 12. In some embodiments, the peracetate solution has a molar ratio of peracetate anions to peracid ranging from about 60:1 to about 6000:1. In some embodiments, the peracetate solution has a molar ratio of peracetate to hydrogen peroxide of greater than about 16:1. The peracetate oxidant solution may provide enhanced treatment methods of bleaching, brightening, and delignifying pulp fibers involving the use of peracetate oxidant solutions.

A method for electrolysis-ozone-corrosion inhibitor/electrolysis-ozone-hydrogen peroxide-corrosion inhibitor coupling treatment on toxic and refractory wastewater includes the following steps: adding toxic and refractory wastewater to be treated into a wastewater treatment reaction tank equipped with a plate anode and a plate cathode, and starting a direct current (DC) power supply connected to the plate anode and the plate cathode to treat the toxic and refractory wastewater at an appropriate current density under stirring, during which a corrosion inhibitor and hydrogen peroxide are added to the toxic and refractory wastewater to be treated and ozone is introduced into the toxic and refractory wastewater to be treated through an aeration device. The method can increase the production rate and production quantity of free radicals in a reaction system, effectively improve the treatment efficiency for toxic and refractory wastewater, and reduce the treatment cost.

In an embodiment, a circuit includes: a transformer defining an inductive footprint within a first layer; a grounded shield bounded by the inductive footprint within a second layer separate from the first layer; and a circuit component bounded by the inductive footprint within a third layer separate from the second layer, wherein: the circuit component is coupled with the transformer through the second layer, and the third layer is separated from the first layer by the second layer.

A method and system are disclosed for determining surfactant concentration levels in aqueous solutions. In accordance with the method of the present disclosure, a related carbon parameter, such as COD or TOC, is measured in an aqueous solution. This measurement is then converted to surfactant concentration using a mathematical correlation or reference data. Through the method and system of the present disclosure, surfactant concentrations in process streams can be monitored and adjusted on the fly.