OCR Text |
Show N X 2 - iCH4 ~ /" r-- // '/ ~ ~ a/ V/ ~ ~ K / V)', ~ ~ 6 / / ~ ~) / V/ 1 2 ~ t-" o 900 lCXXl llOO 100 1)00 100 ~::l[t~ g: 900 lCXXl lCXXl 1200 1)00 1~00 ~ ~ oon~ . ~':w,m:t1d o 900 lClX) llOO 1200 1) 00 1~00 TEMPERATURE, ·C TIME OF PYROLYSIS , SEC : 1 - 0.48 2 - 0.32 3 - 0.22 Fig. 4 - T'nermal Pyrolysis of Methane (1) PYRfT80N BURNER EXTERNAl fl Allf ENY£! OPE AI OUT HEATING PROCESS PARAME1ERS Fig. 5 - Pyretron Ccmbustion & Heating Process Flow Diagram 100 1 2 3 4 ",,90 z- 80 o H70 E-< ~60 u ~50 til ~40 g; 30 tj20 c>: )310 Cl o y// / ...- ------ - I I / /' ~ - ....::::::::: 1/ / / / ~ !1 :; / V / I / / / II / / v - 1/ // /' -- - /!// / /' ./'" IV /' /' . 05.1 .2 .3 . 4 TIME, SEC .5 . 6 0 . 7 1 - 2600 0K 2 - 2400 0K 3 - 2200 0K 4 - 20000K 5 - 1800 0K 6 - 1600 0K 7. - 1500 0K 8 - 1400 0K 9 - 1300 0K FIg. 6 - Degree of Methane Disassociatiull in Pyrolytic Zone of Flame (Calculated) 175 CONTROLLABILITY - The t rad it i ona 1 approach to control in industrial heating processes involves controlling the flow of fuel based on the difference between the process temperature set point and the current temperature, and controlling the f low of oxidizer (air, oxygen or oxygen enriched air) to maintain a fixed ratio. This control approach is able to vary the level of excess oxygen in the flue gases and to maximize heat input but it is unable to influence flame temperature, velocity or luminosity at a fixed heat input level or the level of excess or deficit oxygen in the combustion products. The Pyretron combustion system provides a higher level of control by the independent and accurate control of the introduction of two distinct oxidizers having significant differences in oxygen content. The system provides for: -optimization of the amount of fuel, oxygen and heat input in the pyrolytic zone responsible for emissivity and combustion stability -the intensive mixing of fuel and oxidizer inside the burner tunnel to provide the desired expansion uf combustion products before they leave the burner tunnel thus insuring high flame velocity and turbulence. -reducing the level of exces~ oxygen required for complete com-bustion to less than 1% -a reduction in NOx formation inside the hot central zone of the flame envelope Through such accomplishments the PYRETRON combustion system provides added control of the combustion and heating process by controlling such parameters as flame velocity, temperature distribution in the flame pattern, flame luminosity, heat release into different zones of the flame pattern and zone chemistry. This added control provides: -increased convective heat exchange by high flame velocity and insured flame stability -increased radiative heat exchange from a highly luminous gas flame core at high temperatures -maximum combined radiative and convective heat transfer based on process temperature -minimum excess oxygen required for complete combustion of the fuel -hot excess oxidizer on command when needed for the process -a high temperature, fuel rich flame when needed |