Non-methane total hydrocarbons analysis apparatus and method for the same

A non-methane total hydrocarbons analysis method comprising the steps of:

• providing a non-methane total hydrocarbons analysis apparatus including a six-pass valve, a quantification ring, a first stored gas pipe, a second stored gas pipe, a multi-pass valve, a molecular sieve filling pipe, a first air source and a detector,
• the six-pass valve having a sample entering hole, a multi-pass valve interface, a quantification ring first interface, a first stored gas pipe outlet, a second stored gas pipe interface and a quantification ring second interface,
• the multi-pass valve comprising a first air admission hole, a first discharge hole, a six-pass valve interface, a molecular sieve first interface, a molecular sieve second interface and a first stored gas pipe inlet,
• the quantification ring second interface, the quantification ring and the quantification ring first interface being in communication successively,
• the multi-pass valve interface being in communication with the six-pass valve interface through a pipeline, the molecular sieve first interface, the molecular sieve filling pipe and the molecular sieve second interface being in communication successively through a pipeline,
• the first stored gas pipe inlet, the first stored gas pipe, the first stored gas pipe outlet, the second stored gas pipe interface, the second stored gas pipe and the detector being in communication successively through a pipeline, the first air source being in communication with the first air admission hole,
• the six-pass valve having a load status bit and an entered sample status bit, with the load status bit allowing the sample entering hole to be in communication with the quantification ring second interface, the multi-pass valve interface being in communication with the quantification ring first interface, and the first stored gas pipe outlet being in communication with the second stored gas pipe interface, and with the entered sample status bit allowing the sample entering hole being in communication with the multi-pass valve interface, the quantification ring first interface being in communication with the first stored gas pipe outlet, and the second stored gas pipe interface being in communication with the quantification ring second interface,
• the multi-pass valve having a load status bit and an entered sample status bit, with the load status bit allowing the first air admission hole being in communication with the first discharge hole, the six-pass valve interface being in communication with the molecular sieve first interface, and the molecular sieve second interface being in communication with the first stored gas pipe inlet, and with the entered sample status bit allowing the first discharge hole being in communication with the six-pass valve interface, and the first stored gas pipe inlet being in communication with the first air admission hole;
• configuring the six-pass valve and the multi-pass valve to have the load status bit each, conveying a gas under test from the sample entering hole to the six-pass valve, passing the gas through the quantification ring second interface and the quantification ring successively to thereby fill the quantification ring with the gas, conveying the gas from the quantification ring first interface to the six-pass valve, conveying the gas to the six-pass valve interface through the multi-pass valve interface, conveying the gas to a molecular sieve filling pipe through the molecular sieve first interface, wherein non-methane total hydrocarbons in the gas are adsorbed and filtered out by the molecular sieve to therefore produce a background gas which contains methane hydrocarbons only, and then the background gas enters the multi-pass valve again through the molecular sieve second interface, enters the first stored gas pipe through the first stored gas pipe inlet, and fills the first stored gas pipe, wherein, thereafter, the background gas passes through the first stored gas pipe outlet and the second stored gas pipe interface successively, enters the second stored gas pipe, fills the second stored gas pipe and eventually enters the detector;
• and
• configuring six-pass valve and the multi-pass valve to have the entered sample status bit each, passing a zero-grade air from the first air source to the multi-pass valve through the first air admission hole, conveying the zero-grade air to the detector through the first stored gas pipe inlet, the first stored gas pipe, the first stored gas pipe outlet, the quantification ring first interface, the quantification ring, the quantification ring second interface, the second stored gas pipe interface, and the second stored gas pipe successively, conveying the background gas from the second stored gas pipe to the detector, conveying the gas under test from the quantification ring to the detector, and conveying the background gas from the first stored gas pipe to the detector, such that the background gas which contains methane hydrocarbons only is detected to thereby function as a baseline of a non-methane total hydrocarbons chromatographic peak.