The present disclosure generally relates to producing chloride dioxide. A chlorine dioxide reactor, methods for producing chlorine dioxide, and treating aqueous systems are disclosed. The reactor may include a mixing device, a first feed line in fluid communication with the mixing device, and a second feed line in fluid communication with the mixing device. The reactor may include a proximal portion in fluid communication with the mixing device and a distal portion in fluid communication with a motive water line. The mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line may be positioned within the motive water line.

Aqueous solutions of hydrogen peroxide and alkali metal chlorate are stabilized by a polymeric stabilizer selected from phosphino polycarboxylic acid, poly(acrylic acid), a poly(acrylic acid)-acrylamidoalkylpropane sulfonic acid co-polymer and a poly(acrylic acid)-acrylamidoalkylpropane sulfonic acid-sulfonated styrene terpolymer.

A method of producing chlorine dioxide is disclosed. The method may include feeding a reaction mixture into a separator. The reaction mixture may follow a helical path through the separator and produce gaseous chlorine dioxide within the separator. Gaseous chlorine dioxide may be withdrawn from the separator and used to disinfect process water.

The present disclosure generally relates to methods of treating process water using a reactor for generating chlorine dioxide onsite. The onsite generation system may include double ensured precursor feeding, effective reactor, automated control/alarm, and effective product delivery. The reactor may include a mixing device, a first feed line connected to the mixing device, and a second feed line connected to the mixing device. The reactor may include a proximal portion in fluid communication with the mixing device and a distal portion in fluid communication with a motive water line. The mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line may be positioned within the motive water line.

A method for preparing high-purity chlorine dioxide by using methanol and hydrogen peroxide as a reducing agent includes injecting concentrated sulfuric acid and sodium chlorate solution into a generator system to form a reaction mother liquid. The method also includes adding the reducing agent into the reaction mother liquid to produce chlorine dioxide gas and by-product sodium sulfate. The method further includes cooling and absorbing the produced chlorine dioxide gas by 4-10 C. chilled water to obtain a chlorine dioxide aqueous solution. The by-product sodium sulfate is filtered, washed, and recycled.

The invention discloses a method for preparing high-purity chlorine dioxide by using methanol and hydrogen peroxide as reducing agent. The method comprises: concentrated sulfuric acid and sodium chlorate solution are injected into the generator to form the reaction mother liquid. The reaction mother liquid shall be maintained a certain acidity, temperature and sodium chlorate content, and then it is reacted with the reducing agent (methanol and hydrogen peroxide) to produce chlorine dioxide gas and by-product sodium sulfate. The chlorine dioxide gas is cooled and absorbed by low temperature chilled water to obtain an aqueous solution of chlorine dioxide, and by-products are recycled. The chlorine dioxide solution produced by the aforementioned method has a 60-70% reduction in the Cl2 content and 14-20% reduction in sulfuric acid consumption than that of the chlorine dioxide produced by using a single methanol reducing agent, and the by-product produced is sodium sulfate, not sodium hydrogen sulfate, so neutralization reaction treatment is not required.

The use of a single phase aqueous hydrogen peroxide composition, comprising from 5 to 75% by weight of hydrogen peroxide and from 3 to 150 mg/kg of at least one alkyl phosphate, the composition having a total organic carbon content from organic compounds other than alkyl phosphates of less than 200 mg/kg, reduces foam formation in a method for producing chlorine dioxide by reacting an alkali chlorate with hydrogen peroxide composition in an acidic aqueous medium boiling at sub-atmospheric pressure.

A method of controlling a chemical reaction is disclosed. The method may include feeding a solution at a first flow rate into a reactor and detecting a sound in the reactor using a sound sensor that is adjacent to the reactor. The sound sensor may convert the sound into a sound signal. After the sound signal is acquired, it is compared to a stored sound signal or a stored sound threshold to detect a reaction event. The method may include adjusting the flow rate of solutions into the reactor in response to the reaction event.

The present disclosure generally relates to methods of treating process water using a reactor for generating chlorine dioxide onsite. The onsite generation system may include double ensured precursor feeding, effective reactor, automated control/alarm, and effective product delivery. The reactor may include a mixing device, a first feed line connected to the mixing device, and a second feed line connected to the mixing device. The reactor may include a proximal portion in fluid communication with the mixing device and a distal portion in fluid communication with a motive water line. The mixing device, the reactor, a portion of the first feed line, and a portion of the second feed line may be positioned within the motive water line.

A high-purity chlorine dioxide gas may use hydrogen peroxide as a reducing agent and may use horizontal generator, evaporation crystallizer, dryer and other devices to produce chlorine dioxide gas (product) and sodium sulfate (by-product). Compared to the conventional chlorine dioxide preparation system, the chlorine dioxide reaction and the sodium sulfate crystallization are performed in two processes. These processes are relatively separate and independent, and continuously produce chlorine dioxide gas with high purity and low moisture content while the by-product salt cake is evaporated, crystallized, filtered and dried, thereby producing sodium sulfate, without generating solid and liquid waste.