N0x and 100 % for S02 5.0THER FIELDS AT RANDOM 5-1. Industrial Liquid Hearing. In order ro save energy, ehe replacemenc of cencrnlized wacer heacing boilers was necessary and more efficienc devices had ro be designed. The principle of ehe submerged combuscion has been known for a long time, but burners able ro scand a varying back-pressure were not available. As for immersed cubes, chey were already in use but cheir effıciency was very low. In ehe Submerged Combuscıon, a direcc heac cxchangc becween ehe liquid ro be heaced and ehe cobuscion produccs from a parcicular burner is realizecl: ehe burner is an "opposire swirls burner", mounrecl on ascraighc cube placed inro ehe liquid. When a sufficienr beighr ofwarer is mainrained above ehe dispersion cubes (ebat is ro say around 50 cm), rbe flue gases leave rhe barh ar ehe remperarure ofrhe barh. This means rhar when rhe remperarure of rhe barh is lower rhan rhe dew poinr of ehe flue gases, rhe barh will not only recover ehesensible hearofehe flue gases but also some of ehe lacenr hear conrained in ehe wacer vapour from ehe combuscion. Therefore, ehe efficiency is very high. limited by ehe dew poinr value (58 °C for natura! gas in sroechiomerric condicions), rhis process has also a chemical effecr clue ro ehe carbonic acid producecl by ehe mixrure ofCO , in ehe warer, whar may induce an incompacibilicy wirh highly alcaline barhes. In char case an exchanger has ro be used, generally a Compacr Immersıon Tube. Tbe burner (of ehe premix or nozzlemix rype), is mounred on a scainless sreel combusrion chamber, ehe ourler ofwhich has a reduced diamerer in order co increase ehe flowing velociry, ro improve rhe hear exchange by conveccion . A rube is mounred on rhis ourler. Smooch for rhe moment, ir may be finned larer co increase rhe hear exchange. Wirh a power.ourpur ranging from 50 ro 400 kw, rheir oprimum effıciency is around 92-95 % (NCV), wirh a flue g,ıses remperarure around 120" C ac ehe ouclec. This value could be increased by lengchening rhe cube, but ehe addicional invescmenc could be more imporcanr chan ehe corresponding savings. 5-2. Direcr and Infea-Red Drying In ehe cexcile induscry, chree decencrnlized narural g:ıs drying mechods may beused: conveccion, infra-red radiarion and conduccion: * Wirh conveccion, in cradicional dryers, ehe energy consumpcion is around 1.6 kWh/kg of evaporared warer. * Wich infra-red radiarions, wirh a surfacic OO�AL GAZ OERGİSİ SAYI. 29 103 power ourput of 100 kW/m2 , ehe specifıc consumprion is around 1.4 kwh/kg warer. * The principle of ehe drum dryer is based on conclucrion. The evaporaring capaciry is 300 kg warer/h per merer of widrh and ehe specific consumprion around 1 kWh/kg warer evaporared. A sream heared drum has rhe same surfacic power ourpur, but are far less versarile and energy / money saving. For narural gas convecrion and conducrion, a burner has been designed by Gaz de France and developped by rhe AGI company (represenred by Termogaz in Turkey). Ir is a nozzlemix ribbon burner made of many small free jet burners supplied separarely wirh air gas. Due ro irs versariliry (a power ourpuc ranging from 1 ro 30) and irs accuracy, ehe AGI burner is• well suired ro answer every rexrile drying rerrofirring: This burner can be mounred ona hor air runnel dryer (convecrion), as in rhe c.ıse of ehe Taraflex company, where an accuracy in rempernrure is required (± 1 °C across rhe runnel fora 190° C hor air) or in a roraring drum (conducrion), where ehe heared lengrh can be adjusred ro rhe widrh of ehe fabric, as in ehe drying unir of Matın company. Infra-red burners can be inregrared in a drying unir ro boosr ehe drying or ro increase ehe producrion. Due ro rheir high rhermal inerria, rradirional infra-red panels could not be inregrared ro industrial processes and are rhus used for space hearing purposes. The design ofa new low inerria luminous panel, made of cernmic fibers prorecred by a grid, incroduced ehe concepr in paper and rexrile industries, where ehe remperarure musr answer an insranr change. Furrhermore, rhey improve ehe qualiry of rhe drying process: in ehe rexrile indusrry, an infrared preddryer, placed before ehe hor air dryer, prevencs ehe migrarion of ehe dye rowards ehe edges while increasing ehe drying velociry. In ehe paper and cardboard indusrries, an infra-red vaulr prevencs ehe shrinkage of ehe paper edges by levelling ehe moisrure along ehe widrh. 6. CONCLUSION Natura! gas is increasing irs share in indusrry, as ic is a ready answer ro mosr of ehe problems arising ac ehe end of ehe cencury. An efficienc and clean foel, it helps a good energy managemenr and rhe dedicarion of gas people in improving irs image are irs besr promorion. .
RkJQdWJsaXNoZXIy MTcyMTY=