A process for preparing sulfuric acid may involve melting elemental sulfur in a melting stage to give molten sulfur. Sulfuric acid is subsequently produced from the molten sulfur. Further, sulfur-containing offgases formed in the melting stage may be subjected to oxidation in a supplementary oxidation stage in which sulfur-containing components of the offgases are oxidized to sulfur dioxide. The process may further involve processing the sulfur dioxide to give at least one reaction product. The melting stage may be operated without emissions by processing all of the offgases from the melting stage. An apparatus may be employed for carrying out such a process.

A process for preparing sulfuric acid may involve melting elemental sulfur in a melting stage to give molten sulfur. Sulfuric acid is subsequently produced from the molten sulfur. Further, sulfur-containing offgases formed in the melting stage may be subjected to oxidation in a supplementary oxidation stage in which sulfur-containing components of the offgases are oxidized to sulfur dioxide. The process may further involve processing the sulfur dioxide to give at least one reaction product. The melting stage may be operated without emissions by processing all of the offgases from the melting stage. An apparatus may be employed for carrying out such a process.

A sulfuric acid generating system can include: a primary burn chamber; an exhaust pipe extending from the burn chamber at a first end to an opposite second end; a secondary burn chamber located between the first end and second end; and a primary venturi pump having a gas inlet coupled to an outlet at the second end of the exhaust pipe and having an aqueous media inlet and having a fluid outlet. A method of producing sulfurous acid can include: providing sulfur to the primary burn chamber; burning a first portion of the sulfur in the primary burn chamber to form a first portion of sulfur dioxide; burning a second portion of the sulfur in the secondary burn chamber to form a second portion of sulfur dioxide; and mixing the first portion and second portion of sulfur dioxide with an aqueous composition so as to produce aqueous sulfurous acid.

A sulfuric acid generating system can include: a primary burn chamber; an exhaust pipe extending from the burn chamber at a first end to an opposite second end; a secondary burn chamber located between the first end and second end; and a primary venturi pump having a gas inlet coupled to an outlet at the second end of the exhaust pipe and having an aqueous media inlet and having a fluid outlet. A method of producing sulfurous acid can include: providing sulfur to the primary burn chamber; burning a first portion of the sulfur in the primary burn chamber to form a first portion of sulfur dioxide; burning a second portion of the sulfur in the secondary burn chamber to form a second portion of sulfur dioxide; and mixing the first portion and second portion of sulfur dioxide with an aqueous composition so as to produce aqueous sulfurous acid.

A contact process, sulfuric acid system and method are disclosed for producing sulphuric acid with improved operating efficiency in humid environments. The system comprises a pre-drying absorber for pre-drying humid air with weak sulfuric acid. Weak sulfuric acid from the pre-drying absorber is provided to a subsystem comprising two sulfur trioxide absorbers and a heat exchanger for the recovery of heat via steam production. This arrangement allows for a marked increase in steam production (i.e. energy efficiency). In a separate improvement, the emission apparatus for the system can be simplified using a peroxide tail gas scrubber comprising upper and lower scrubber sections in which the upper scrubber section consists essentially of tray type scrubbers.

A contact process, sulfuric acid system and method are disclosed for producing sulphuric acid with improved operating efficiency in humid environments. The system comprises a pre-drying absorber for pre-drying humid air with weak sulfuric acid. Weak sulfuric acid from the pre-drying absorber is provided to a subsystem comprising two sulfur trioxide absorbers and a heat exchanger for the recovery of heat via steam production. This arrangement allows for a marked increase in steam production (i.e. energy efficiency). In a separate improvement, the emission apparatus for the system can be simplified using a peroxide tail gas scrubber comprising upper and lower scrubber sections in which the upper scrubber section consists essentially of tray type scrubbers.

A sulfuric acid generating system can include: a primary burn chamber; an exhaust pipe extending from the burn chamber at a first end to an opposite second end; a secondary burn chamber located between the first end and second end; and a primary venturi pump having a gas inlet coupled to an outlet at the second end of the exhaust pipe and having an aqueous media inlet and having a fluid outlet. A method of producing sulfurous acid can include: providing sulfur to the primary burn chamber; burning a first portion of the sulfur in the primary burn chamber to form a first portion of sulfur dioxide; burning a second portion of the sulfur in the secondary burn chamber to form a second portion of sulfur dioxide; and mixing the first portion and second portion of sulfur dioxide with an aqueous composition so as to produce aqueous sulfurous acid.

A sulfuric acid generating system can include: a primary burn chamber; an exhaust pipe extending from the burn chamber at a first end to an opposite second end; a secondary burn chamber located between the first end and second end; and a primary venturi pump having a gas inlet coupled to an outlet at the second end of the exhaust pipe and having an aqueous media inlet and having a fluid outlet. A method of producing sulfurous acid can include: providing sulfur to the primary burn chamber; burning a first portion of the sulfur in the primary burn chamber to form a first portion of sulfur dioxide; burning a second portion of the sulfur in the secondary burn chamber to form a second portion of sulfur dioxide; and mixing the first portion and second portion of sulfur dioxide with an aqueous composition so as to produce aqueous sulfurous acid.

A method of producing sulfuric acid can include: obtaining a microbial culture that produces sulfuric acid; placing the microbial culture in a bioreactor in an aqueous environment; introducing an aqueous, liquid or gaseous sulfur supply into the bioreactor; and culturing the microbial culture with the sulfur supply sufficiently so that sulfuric acid is produced. The sulfur supply can be from aqueous or gaseous sulfur dioxide and/or dihydrogen sulfide, or sulfurous acid. The microbes are any microbes that processes sulfur, such as natural microbes that processes sulfur, genetically modified microbes that processes sulfur, cultivated microbes en.) that processes sulfur, purchased microbes that processes sulfur. The microbes may also include other type of microbes that facilitate culturing of the sulfuric acid producing microbes. The sulfuric acid can be produced at ambient conditions. In one aspect, the process is a batch process or a continuous process.

A method of producing sulfuric acid can include: obtaining a microbial culture that produces sulfuric acid; placing the microbial culture in a bioreactor in an aqueous environment; introducing an aqueous, liquid or gaseous sulfur supply into the bioreactor; and culturing the microbial culture with the sulfur supply sufficiently so that sulfuric acid is produced. The sulfur supply can be from aqueous or gaseous sulfur dioxide and/or dihydrogen sulfide, or sulfurous acid. The microbes are any microbes that processes sulfur, such as natural microbes that processes sulfur, genetically modified microbes that processes sulfur, cultivated microbes en.) that processes sulfur, purchased microbes that processes sulfur. The microbes may also include other type of microbes that facilitate culturing of the sulfuric acid producing microbes. The sulfuric acid can be produced at ambient conditions. In one aspect, the process is a batch process or a continuous process.