A turbulence generating device for generating turbulence and vortices in a fluid inside a fluid transfer pipe, which acts as a heat transfer pipe, such that, by increasing the area of contact of the fluid with the pipe and the time of contact, not only sufficient heat exchange and heat radiation are conducted, but alien substances and the like, which accumulate inside the corresponding pipe, can also be removed.

A turbulence generating device for generating turbulence and vortices in a fluid inside a fluid transfer pipe, which acts as a heat transfer pipe, such that, by increasing the area of contact of the fluid with the pipe and the time of contact, not only sufficient heat exchange and heat radiation are conducted, but alien substances and the like, which accumulate inside the corresponding pipe, can also be removed.

A heat exchanger includes a plurality of fins spaced apart from each other such that gas flows therebetween, and a plurality of heat transfer tubes extending through the plurality of fins and joined to the plurality of fins by tube expansion. The heat transfer tubes are arranged in five or more columns along a flow direction of the gas and staggered in a row direction intersecting the flow direction of the gas. Each of the plurality of fins is flat and plate-shaped and continuously extends between the heat transfer tubes in the flow direction of the gas. The plurality of heat transfer tubes satisfy relationships of 1.055DDa1.068D and 1.56DaL2.58Da, where D is an unexpanded outside diameter of the heat transfer tubes, Da is an expanded outside diameter thereof, and L is a distance between centers of adjacent two heat transfer tubes.

A heat exchanger includes a plurality of fins spaced apart from each other such that gas flows therebetween, and a plurality of heat transfer tubes extending through the plurality of fins and joined to the plurality of fins by tube expansion. The heat transfer tubes are arranged in five or more columns along a flow direction of the gas and staggered in a row direction intersecting the flow direction of the gas. Each of the plurality of fins is flat and plate-shaped and continuously extends between the heat transfer tubes in the flow direction of the gas. The plurality of heat transfer tubes satisfy relationships of 1.055DDa1.068D and 1.56DaL2.58Da, where D is an unexpanded outside diameter of the heat transfer tubes, Da is an expanded outside diameter thereof, and L is a distance between centers of adjacent two heat transfer tubes.

In an embodiment, a method of producing a carbonate comprises reacting carbon monoxide and chlorine in a phosgene reactor in the presence of a catalyst to produce a first product comprising phosgene; wherein carbon tetrachloride is present in the first product in an amount of 0 to 10 ppm by volume based on the total volume of phosgene; and reacting a monohydroxy compound with the phosgene to produce the carbonate; wherein the phosgene reactor comprises a tube, a shell, and a space located between the tube and the shell; wherein the tube comprises one or more of a mini-tube section and a second tube section; a first concentric tube concentrically located in the shell; a twisted tube; an internal scaffold; and an external scaffold.

In an embodiment, a method of producing a carbonate comprises reacting carbon monoxide and chlorine in a phosgene reactor in the presence of a catalyst to produce a first product comprising phosgene; wherein carbon tetrachloride is present in the first product in an amount of 0 to 10 ppm by volume based on the total volume of phosgene; and reacting a monohydroxy compound with the phosgene to produce the carbonate; wherein the phosgene reactor comprises a tube, a shell, and a space located between the tube and the shell; wherein the tube comprises one or more of a mini-tube section and a second tube section; a first concentric tube concentrically located in the shell; a twisted tube; an internal scaffold; and an external scaffold.

A cooling system comprises a compressor, a condenser, an expansion valve, and a heat exchanger. The latter comprises a vessel for containing a refrigerant, the vessel having an inner space bounded by a closed surface of a vessel wall, the vessel comprising an inlet and an outlet for transport of refrigerant into and out of the inner space through the vessel wall. A tube is disposed at least partly inside the inner space, wherein a first end of the tube is fixed to a first orifice of the vessel wall and a second end of the tube is fixed to a second orifice of the vessel wall to enable fluid communication into and/or out of the tube through the first orifice and the second orifice. A pressure control means controls a pressure in the inner space based on a target temperature.

A vessel for containing a refrigerant comprising an inner wall and an outer wall arranged concentrically and having an inner space bounded by the inner wall and outer wall, an inlet and an outlet for transport of refrigerant into and out of the inner space; a tube inside the inner space arranged turn around the inner wall; an input tube fluidly connected to the inner space and arranged to allow flow of the refrigerant through the input tube into the inner space; an output tube connected to the inner space and arranged to allow flow of the refrigerant out of the inner space into the output tube; a compressor arranged to receive the refrigerant from the output tube and to compress the refrigerant; and a condenser arranged to receive the compressed refrigerant fluid from the compressor, to condense the refrigerant, and to forward the compressed refrigerant into the input tube.

In an embodiment, a method of producing a carbonate comprises reacting carbon monoxide and chlorine in a phosgene reactor in the presence of a catalyst to produce a first product comprising phosgene; wherein carbon tetrachloride is present in the first product in an amount of 0 to 10 ppm by volume based on the total volume of phosgene; and reacting a monohydroxy compound with the phosgene to produce the carbonate; wherein the phosgene reactor comprises a tube, a shell, and a space located between the tube and the shell; wherein the tube comprises one or more of a mini-tube section and a second tube section; a first concentric tube concentrically located in the shell; a twisted tube; an internal scaffold; and an external scaffold.

In an embodiment, a method of producing a carbonate comprises reacting carbon monoxide and chlorine in a phosgene reactor in the presence of a catalyst to produce a first product comprising phosgene; wherein carbon tetrachloride is present in the first product in an amount of 0 to 10 ppm by volume based on the total volume of phosgene; and reacting a monohydroxy compound with the phosgene to produce the carbonate; wherein the phosgene reactor comprises a tube, a shell, and a space located between the tube and the shell; wherein the tube comprises one or more of a mini-tube section and a second tube section; a first concentric tube concentrically located in the shell; a twisted tube; an internal scaffold; and an external scaffold.