Economic and environmental analysis of the procedures for waste glycerol utilization

Proizvodnja in poraba biogoriv se povečujeta, eno izmed teh je tudi biodizel. Pri njegovi proizvodnji nastaja kot stranski produkt glicerol, ki ima za proizvajalce neugoden ekonomski učinek, zato iščejo nove postopke za porabo oz. prodajo odpadnega glicerola. Osnovna ideja te diplomske naloge je, da bi uporabili glicerol v svečarstvu. Pri tem se soočamo z več problemi, od katerih sta najbolj pereča slaba gorljivost glicerola in to, da se ne meša s parafinom. V diplomski nalogi smo naredili laboratorijske eksperimente, s katerimi smo raziskovali, na kakšen način bi bilo mogoče dodajati glicerol parafinu, da bi dobili sveče, ki bi imele primerljive lastnosti gorenja kot klasične parafinske sveče. Na osnovi rezultatov eksperimentov smo predlagali preliminarne procesne sheme za štiri postopke, pri katerih bi lahko potencialno uporabili glicerol v svečarstvu. Ti postopki so: • Proces z maščobnimi kislinami dolgih verig, pri katerem bi surovine stale med 820 €/t in 865 €/t in je najbolj ekološki postopek. • Proces z dodatkom etanola, pri katerem bi bili stroški surovin okoli 850 €/t, vendar je pri tem postopku problem metanol v denaturiranem alkoholu, hlapnost le-tega ter higroskopičnost glicerola. • Proces z adipinsko kislino, pri katerem bi za surovine porabili 1 020 €/t, vendar je glavni problem škodljivost katalizatorja. • Proces z dodatkom baze pri razmerju parafin : glicerol 80 : 20, pri katerem porabimo za surovine okoli 1 000 €/t, problem pri tem postopku pa je strupenost natrijevega hidroksida v večji količini.Production and consumption of biofuels is increasing, one of them being also a biodiesel. A byproduct glycerol is produced during its production, which is unfavorable for the economic efficiency, and therefore, the producers search for new opportunities of waste glycerol usage and sales. The basic idea of this thesis is to introduce glycerol in candle production. There are several problems associated with this, especially poor combustibility of glycerol and non-miscibility with paraffin. In this thesis, several laboratory experiments were carried out in order to discover the options for adding glycerol to paraffin, and producing candles with comparable burning characteristics than traditional paraffin candles. Based on the experimental results, preliminary process schemes for four processes were proposed, which could potentially use waste glycerol in candle production. These procedures are: • The process involving fatty acids with long chains, in which the raw materials would cost between 820 €/t and 865 €/t, and would be the most ecological process. • The process involving ethanol, in which the costs of raw materials would amount around 850 €/t, but the problem in this case would be a presence of a methanol in denatured ethanol, its volatility and glycerol\u27s hygroscopicity. • The process involving the adipic acid, in which the raw materials would cost 1,020 €/t but the main problem would be the harmfulness of the catalyst. • The process with an addition of a base at a ratio of paraffin : glycerol 80 : 20, in which the cost of the raw materials would be about 1,000 €/t. A drawback of this process would be a toxicity of sodium hydroxide in a larger amount