A method for the management of phosphogypsum consists in that a reactor (2) is charged with apatite and/or phosphorite phosphogypsum and with an aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate from a pre-reactor (1), at 1: (0.1-4) ratio of phosphogypsum to the aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate, the entire contents are stirred at 10 C. to 200 C. for at least 2 minutes, CO.sub.2 being released in the course of the process is directed to the pre-reactor (1), and the post-reaction mixture is directed to a filter (3) to obtain an aqueous ammonium sulphate solution, whereas the precipitate from the filter (3) is heat-treated, followed by dissolving it in nitric acid in a reactor (5), and the resultant suspension is filtered through a filter (6) to obtain an aqueous calcium nitrate solution, and CO.sub.2 being released in the reactor (5) is recirculated to the pre-reactor (1) wherein CO.sub.2 is reacted with ammonia in an aqueous solution to obtain the aqueous or ammoniacal solution of carbonate and/or bicarbonate which is directed to the reactor (2), with the process for obtaining the aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate being conducted until the pH 7-12 of the solution is reached.

Apparatus and methods for treating acid gas, which utilizes multi-stage absorption cycle of ammonia desulfurization to treat acid tail gas after pre-treatment of the acid gas, thereby achieving the purpose of efficient and low-cost treatment of acid tail gas. The parameters of the acid tail gas may be adjusted by a regulatory system such that the enthalpy value of the acid tail gas is in the range of 60-850 kJ/kg dry gas, for example, 80-680 kJ/kg dry gas or 100-450 kJ/kg dry gas, to meet the requirements of ammonia desulfurization, and achieve the synergy between the acid gas pre-treatment and ammonia desulfurization. Furthermore, hydrogen sulfide may be converted into sulfur/sulfuric acid plus ammonium sulfate at an adjustable ratio.

Apparatus and methods for treating acid gas, which utilizes multi-stage absorption cycle of ammonia desulfurization to treat acid tail gas after pre-treatment of the acid gas, thereby achieving the purpose of efficient and low-cost treatment of acid tail gas. The parameters of the acid tail gas may be adjusted by a regulatory system such that the enthalpy value of the acid tail gas is in the range of 60-850 kJ/kg dry gas, for example, 80-680 kJ/kg dry gas or 100-450 kJ/kg dry gas, to meet the requirements of ammonia desulfurization, and achieve the synergy between the acid gas pre-treatment and ammonia desulfurization. Furthermore, hydrogen sulfide may be converted into sulfur/sulfuric acid plus ammonium sulfate at an adjustable ratio.

Conversion methods and equipment for converting a calcium-based flue gas desulfurization (FGD) system to an ammonia-based FGD systems, including modifying a reagent system and absorber system of the calcium-based FGD system to be capable of, respectively, delivering an ammonia-based reagent to the absorber system rather than the calcium-based reagent, and modifying the absorber system to increase capacity of a reaction tank thereof.

Conversion methods and equipment for converting a calcium-based flue gas desulfurization (FGD) system to an ammonia-based FGD systems, including modifying a reagent system and absorber system of the calcium-based FGD system to be capable of, respectively, delivering an ammonia-based reagent to the absorber system rather than the calcium-based reagent, and modifying the absorber system to increase capacity of a reaction tank thereof.

A method for producing a dry reagent composition includes preparing a reagent solution including a Good's buffer in a concentration of more than 2.5 mM, an ammonium salt, a drying protection agent, and a nucleic acid amplification enzyme, and drying the reagent solution. A method for suppressing a decrease in enzyme activity during drying includes adding a Good's buffer in a biochemical reagent comprising an ammonium salt and an enzyme prior to drying the enzyme.

A method for producing a dry reagent composition includes preparing a reagent solution including a Good's buffer in a concentration of more than 2.5 mM, an ammonium salt, a drying protection agent, and a nucleic acid amplification enzyme, and drying the reagent solution. A method for suppressing a decrease in enzyme activity during drying includes adding a Good's buffer in a biochemical reagent comprising an ammonium salt and an enzyme prior to drying the enzyme.

A system for the production of ammonium sulfate granules including a pipe cross reactor (PCR) configured to contact concentrated sulfuric acid with anhydrous ammonia to produce a PCR product comprising ammonium sulfate; and a granulator fluidly connected to the PCR, whereby PCR product extracted from the PCR can be introduced into the granulator, an inlet for ammonium sulfate seed material, an ammonia sparger configured to spray liquid anhydrous ammonia onto a bed of ammonium sulfate granules within the granulator, and a granulator product outlet configured for extraction of granulator product comprising ammonium sulfate granules from the granulator. A method of producing ammonium sulfate granules is also provided.

Compositions for removing air pollutants from the air are provided. These compositions can be sprayed on a variety of surfaces to remove air pollutants such as volatile organic compounds (VOCs) from the environment, and are suitable for use in human dwellings.

Compositions for removing air pollutants from the air are provided. These compositions can be sprayed on a variety of surfaces to remove air pollutants such as volatile organic compounds (VOCs) from the environment, and are suitable for use in human dwellings.