A raw material gas supply apparatus is configured to obtain a difference between a set value and a measured value of a vaporized raw material, add the difference as a correction value to the set value of the flow rate of the carrier gas to maintain an amount of the vaporized raw material at the set value, and subtract a difference from a set value of a flow rate of the dilution gas to maintain a total flow rate of the carrier gas and the dilution gas at a constant level. The amount of the vaporized raw material is calculated by subtracting an integration value of a measured value of the flow rate of the inert gas in the supply period of the raw material gas from an integration value of the flow rate of the raw material gas which is measured in the supply period.

The present disclosure provides a system and method for odorizing natural gas flowing through a distribution pipeline. The system includes a bypass line adjacent to a distribution pipeline, wherein bypass gas flows through the bypass line and an odorant tank connected to the bypass line, and into the distribution pipeline; a high-flow control valve and a low-flow control valve in the bypass line, wherein bypass gas flows through the odorant tank into the distribution pipeline when the high-flow control valve or the low-flow control valve is open; and a programmable logic controller connected to the high-flow and low flow control valve; wherein the programmable logic controller opens the high-flow or low-flow control valve for a predetermined dwell time proportional to an amount of bypass gas needed to odorize gas in the distribution pipeline each time that a preselected quantity of gas flows through the distribution pipeline.

A control valve includes a valve body and a valve gate, the valve body has an inner space, first fluid inlets, second fluid inlets, and a fluid outlet, the valve gate is movably located inside the inner space, the first fluid inlets are located at a side of the fluid outlet, the second fluid inlets are located at another side of the fluid outlet, the first fluid inlets and the second fluid inlets are arranged along a radial direction of the valve gate, the valve gate has a main channel having a first inlet end, a second inlet end, and an outlet end, the first inlet end is connected to the first fluid inlets, the second inlet end is connected to the second fluid inlets, and the outlet end is connected to the fluid outlet.

The disclosure provides a control valve which includes a valve body and a valve gate. The valve gate is movably located inside the inner space. The control valve has a lower flow rate limit which is greater than zero. That is, the lower flow rate limit has no necessary to be zero, thus it is acceptable to have a cylindrical valve gate but not a spherical valve gate, and a diameter of the cylindrical valve gate is be smaller than a caliber of an opening of the valve body. Therefore, the valve gate can be directly installed into the valve body via the opening, which allows the valve body to be made of a single piece so as to simplify the processes of manufacturing and assembly.

The disclosure provides a control valve which includes a valve body and a valve gate. The valve gate is movably located inside the inner space. The control valve has a lower flow rate limit which is greater than zero. That is, the lower flow rate limit has no necessary to be zero, thus it is acceptable to have a cylindrical valve gate but not a spherical valve gate. Therefore, the valve gate can be directly installed into the valve body via the opening, which allows the valve body to be made of a single piece so as to simplify the processes of manufacturing and assembly.

The present disclosure provides a system and method for odorizing natural gas flowing through a distribution pipeline. The system includes a bypass line adjacent to a distribution pipeline, wherein bypass gas flows through the bypass line and an odorant tank connected to the bypass line, and into the distribution pipeline; a high-flow control valve and a low-flow control valve in the bypass line, wherein bypass gas flows through the odorant tank into the distribution pipeline when the high-flow control valve or the low-flow control valve is open; and a programmable logic controller connected to the high-flow and low flow control valve; wherein the programmable logic controller opens the high-flow or low-flow control valve for a predetermined dwell time proportional to an amount of bypass gas needed to odorize gas in the distribution pipeline each time that a preselected quantity of gas flows through the distribution pipeline.

The disclosure provides a control valve which includes a valve body having an inner space and a valve gate. The valve gate is movably located inside the inner space of the valve body and the valve gate has at least one main channel having two valve ports opposite to each other, and each of the valve ports of the main channel has a plurality of circular holes and a curved hole, where the circular holes are arranged in a line and the curved hole is connected to one of the circular holes that is located at an end of the line. The control valve has a lower flow rate limit which is greater than zero.

The present disclosure provides a system and method for odorizing natural gas flowing through a distribution pipeline. The system includes a bypass line adjacent to a distribution pipeline, wherein bypass gas flows through the bypass line and an odorant tank connected to the bypass line, and into the distribution pipeline; a high-flow control valve and a low-flow control valve in the bypass line, wherein bypass gas flows through the odorant tank into the distribution pipeline when the high-flow control valve or the low-flow control valve is open; and a programmable logic controller connected to the high-flow and low flow control valve; wherein the programmable logic controller opens the high-flow or low-flow control valve for a predetermined dwell time proportional to an amount of bypass gas needed to odorize gas in the distribution pipeline each time that a preselected quantity of gas flows through the distribution pipeline.

The disclosure provides a control valve which includes a valve body and a valve gate. The valve gate is movably located inside the inner space. The control valve has a lower flow rate limit which is greater than zero. That is, the lower flow rate limit has no necessary to be zero, thus it is acceptable to have a cylindrical valve gate but not a spherical valve gate, and a diameter of the cylindrical valve gate is be smaller than a caliber of an opening of the valve body. Therefore, the valve gate can be directly installed into the valve body via the opening, which allows the valve body to be made of a single piece so as to simplify the processes of manufacturing and assembly.

The present disclosure provides a system and method for odorizing natural gas flowing through a distribution pipeline. The system includes a bypass line adjacent to a distribution pipeline, wherein bypass gas flows through the bypass line and an odorant tank connected to the bypass line, and into the distribution pipeline; a high-flow control valve and a low-flow control valve in the bypass line, wherein bypass gas flows through the odorant tank into the distribution pipeline when the high-flow control valve or the low-flow control valve is open; and a programmable logic controller connected to the high-flow and low flow control valve; wherein the programmable logic controller opens the high-flow or low-flow control valve for a predetermined dwell time proportional to an amount of bypass gas needed to odorize gas in the distribution pipeline each time that a preselected quantity of gas flows through the distribution pipeline.