A pulse jet system and method is disclosed. In an example, the pulse jet system includes a combustion chamber, intake ports to deliver combustion agents to the combustion chamber, an expansion chamber to cool a combustion product following combustion of the combustion agents in the combustion chamber, and an exhaust to exit the cooled gas from the expansion chamber. In another example, the pulse jet system includes a combustion chamber with intake ports to deliver combustion agents to the combustion chamber, wherein the combustion chamber is part of a four cycle engine. The pulse jet system also includes an expansion chamber to cool a combustion product following combustion of the combustion agents in the combustion chamber.

A pulse jet system and method is disclosed. In an example, the pulse jet system includes a combustion chamber, intake ports to deliver combustion agents to the combustion chamber, an expansion chamber to cool a combustion product following combustion of the combustion agents in the combustion chamber, and an exhaust to exit the cooled gas from the expansion chamber. In another example, the pulse jet system includes a combustion chamber with intake ports to deliver combustion agents to the combustion chamber, wherein the combustion chamber is part of a four cycle engine. The pulse jet system also includes an expansion chamber to cool a combustion product following combustion of the combustion agents in the combustion chamber.

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.

The present invention relates to a system and method for desulfurization and denitrification integrated treatment and recycling of flue gas by using red mud, and belongs to the recycling and environmental protection technology field. The system includes a desulfurization spray tower, an ozone generator, a denitration spray tower, a slurry mixing tank, a slurry storage tank, a vacuum filter, an ammonia water neutralization tank, an aluminum hydroxide precipitation tank, an ammonia water tank, an aluminum hydroxide storage tank, a filter press, an ammonia distillation tower, a dephlegmator, a cooler, a concentrated ammonia water storage tank, a gypsum precipitation tank, and an anaerobic biochemical pool. In the present invention, red mud slurry is used for desulfurization and denitrification treatment of flue gas to remove SO.sub.2 and NO in the flue gas, so that SO.sub.2 and NO in the flue gas reach an emission standard.

The invention relates to a drilling fluid resulting from a combination of calcium carbonate, starch, calcium oxide, xanthan gum, and essentially a cationic surfactant, where the cationic surfactant is constituted by the following components: calcium nitrate, diethanolamine (DEA), and glacial acetic acid. Also disclosed is a method for producing the cationic surfactant, a process for obtaining the drilling fluid, as well as a method for measuring the free calcium of the reaction when the fluid is in wellbore operation.

The present invention relates to a system and method for desulfurization and denitrification integrated treatment and recycling of flue gas by using red mud, and belongs to the recycling and environmental protection technology field. The system includes a desulfurization spray tower, an ozone generator, a denitration spray tower, a slurry mixing tank, a slurry storage tank, a vacuum filter, an ammonia water neutralization tank, an aluminum hydroxide precipitation tank, an ammonia water tank, an aluminum hydroxide storage tank, a filter press, an ammonia distillation tower, a dephlegmator, a cooler, a concentrated ammonia water storage tank, a gypsum precipitation tank, and an anaerobic biochemical pool. In the present invention, red mud slurry is used for desulfurization and denitrification treatment of flue gas to remove SO.sub.2 and NO in the flue gas, so that SO.sub.2 and NO in the flue gas reach an emission standard.

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.

The invention concerns a method of treating phosphate-containing waste, in particular phosphate-containing ash from waste-incineration plants, by wet-chemical digestion in order to obtain compounds of aluminum, calcium, phosphorus and nitrogen.

The invention concerns a method of treating phosphate-containing waste, in particular phosphate-containing ash from waste-incineration plants, by wet-chemical digestion in order to obtain compounds of aluminum, calcium, phosphorus and nitrogen.

A method for complex treatment of phosphogypsum comprising crushing of phosphogypsum and its washing with a solution of sulphuric acid, concentration 2-15%, and stirring at 50-80 C., wherein the resultant mixture is separated into a liquid fraction and a sediment containing mostly calcium sulphate, which is characterized in that metals are precipitated from the liquid fraction, mainly lanthanides, phosphates and sulphates of metals soluble in diluted sulphuric acid, and the sediment containing mostly calcium sulphate is converted in the presence of ammonia liquor and carbon dioxide to ammonium sulphate and calcium carbonate, wherein filtered and dried sediment of calcium carbonate is dissolved in a 15-30% solution of nitric acid while stirring continuously, and then the resultant CO.sub.2 is recirculated and used in the conversion of the first phase of the sediment, and the resultant mixture is separated into a solution of calcium nitrate with dissolved metals and a sediment of fluorides and silicates with metal precipitate.