Kinetics of Anaerobic Digestion of Dairy Fat Waste with Saponification Pre-Treatment

https://doi.org/10.22146/jrekpros.48959

Rifki Wahyu Kurnianto(1*), Wiratni Budhijanto(2), Rochim Bakti Cahyono(3)

(1) Department of Chemical Engineering, Faculty of Engineering, Universitas Gadjah Mada, Jl Grafika No. 2 Kampus UGM, 55281 Yogyakarta
(2) Department of Chemical Engineering, Faculty of Engineering, Universitas Gadjah Mada, Jl Grafika No. 2 Kampus UGM, 55281 Yogyakarta
(3) Department of Chemical Engineering, Faculty of Engineering, Universitas Gadjah Mada, Jl Grafika No. 2 Kampus UGM, 55281 Yogyakarta
(*) Corresponding Author

Abstract


Anaerobic digestion has been an attractive field of research in the era of energy crisis. Biogas, which is the product of anaerobic digestion, provides alternative energy, while at the same time it also prevents pollution due to organic waste accumulation. Among various organic wastes, dairy fat waste is a potential substrate for anaerobic digestion. Fat waste has high theoretical biogas potential because of its high lipid content. However, anaerobic digestion of organic waste with high lipid content is quite challenging. The main obstacle in anaerobic digestion of fat waste is its tendency to form insoluble floating layer on top of the liquid phase. This phenomenon hinders the access of hydrolytic bacteria to the substrate. Saponification is one of the methods to increase the solubility of the floating layer and hence to improve the availability of substrate for the bacteria. Saponification changes the lipid content into soap which has both polar and non-polar functional groups and the polar side will increase the solubility of the substrate in water. This study evaluated the effect of different dosage of base added as the reactant during saponification pre-treatment on the productivity of anaerobic digestion of dairy fat waste. The kinetics of the anaerobic digestion process was analyzed by mean of mathematical model. The variations of the alkaline dosages studied for saponification pre-treatment were 0.04 mol base/g sCOD; 0.02 mol base/g sCOD; and no pre-treatment for control reactor. This study proved that saponification increased the solubility of dairy fat waste. This result was confirmed by the hydrolysis constant value (kH) of 0.00782/day for reactor with saponification, which was twenty times of magnitude higher than the kH value of 0.00032/day in the reactor without saponification. However, the exposure to high pH during the saponification pre-treatment might somewhat inhibit indigenous acidogenic bacteria in the waste which results in lower methane yield in the reactors with saponification to be compared to the control reactor.

 

A B S T R A K

Peruraian anaerobik merupakan salah satu bidang riset yang sangat menarik perhatian dalam era krisis energi. Biogas tidak hanya menyediakan energi alternatif, tetapi juga dapat mencegah pencemaran akibat limbah organik. Limbah lemak susu adalah substrat yang potensial untuk proses peruraian anaerobik karena memiliki potensi biogas teoritis yang tinggi akibat kandungan lemaknya yang tinggi. Namun, peruraian anaerobik dari limbah organik dengan kandungan lemak yang tinggi memiliki tantangan tersendiri. Hambatan utama dalam peruraian anaerobik dari limbah lemak susu adalah kecenderungan untuk membentuk lapisan padatan yang tidak larut dan mengapung di bagian atas fase cair. Fenomena ini menghambat akses bakteri hidrolisis terhadap substrat. Saponifikasi adalah salah satu cara untuk meningkatkan kelarutan lapisan padatan tersebut, sehingga meningkatkan ketersediaan substrat untuk bakteri. Saponifikasi akan mengubah kandungan lemak menjadi sabun yang memiliki gugus fungsi polar maupun non-polar. Gugus fungsi yang bersifat polar akan meningkatkan kelarutan substrat dalam air. Studi ini mengevaluasi pengaruh dari berbagai dosis larutan basa yang ditambahkan sebagai reaktan selama perlakuan awal saponifikasi terhadap peruraian anaerobik limbah lemak susu. Kinetika proses peruraian anaerobik dianalisis dengan menggunakan model matematika. Variasi dosis yang diamati pengaruhnya untuk perlakuan awal saponifikasi adalah 0,04 mol basa/g sCOD; 0,02 mol basa/g sCOD; dan nol (tanpa perlakuan awal saponifikasi). Dari penelitian ini, terbukti bahwa saponifikasi berhasil meningkatkan kelarutan limbah lemak susu dan juga ditunjukkan oleh nilai konstanta hidrolisis (kH) 0,00782/hari lebih tinggi dua puluh kali lipat dibandingkan dengan nilai kH 0,00032/hari pada reaktor tanpa saponifikasi. Akan tetapi, penelitian ini juga mengindikasikan bahwa bakteri asidogenik bawaan substrat terhambat kinerjanya oleh paparan pH yang tinggi selama perlakuan awal saponifikasi berlangsung sehingga hasil gas metan yang diperoleh lebih rendah daripada reaktor kontrol.


Keywords


anaerobic digestion; dairy fat waste; hydrolysis; saponification

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References

Battimelli, A., Carrère, H. and Delgenès, J.P., 2009, Saponification of fatty slaughterhouse wastes for enhancing anaerobic biodegradability, Bioresour. Technol., 100 (15), 3695–3700.

Battimelli, A., Torrijos, M., Moletta, R. and Delgenès, J.P., 2010, Slaughterhouse fatty waste saponification to increase biogas yield, Bioresour. Technol., 101, pp. 3388–3393.

BP., 2017, BP Statistical Review of World Energy June 2017

Carrere, H., Antonopoulou, G., Affes, R., Passos, F., Battimelli, A., Lyberatos, G. and Ferrer, I., 2015, Review of feedstock pretreatment strategies for improved, Bioresour. Technol., Elsevier Ltd, available at: https://doi.org/ 10.1016/j.biortech.2015.09.007.

Cavaleiro, A.J., Ferreira, T., Pereira, F., Tommaso, G. and Alves, M.M., 2013, Bioresource Technology Biochemical methane potential of raw and pre-treated meat-processing wastes, Bioresour. Technol., 129, 519–525.

Cioabla, A.E., Ionel, I., Dumitrel, G. and Popescu, F., 2012, Comparative study on factors affecting anaerobic digestion of agricultural vegetal residues, (ii), 1–9.

Cirne, D.G., Björnsson, L., Alves, M.M. and Mattiason, B., 2006, Effects of bioaugmentation by an anaerobic lipolytic bacterium on anaerobic digestion of lipid rich waste, J. Chem. Technol. Biotechnol., 81 (11), 1745–1752.

Clesceri, L.S., Eaton, A.D. and Greenberg, A.E., 2005, Standard Methods for the Examination of Water and Wastewater, Am. Public Heal. Assoc. (APHA), Am. Water Work. Assoc. Water Environ. Fed., 21st ed., American Public Health Association, American Water Works Association, Water Environment Federation, Washington DC.

Cuetos, M.J., Gómez, X., Otero, M. and Morán, A., 2010, Anaerobic digestion and co-digestion of slaughterhouse waste (SHW): Influence of heat and pressure pre-treatment in biogas yield, Waste Manag., 30 (10), 1780–1789.

Deublein, D. and Steinhauser, A., 2008, Biogas from Waste and Renewable Resources: An Introduction, Wiley-VCH, Weinheim.

Halalsheh, M., Koppes, J., Den Elzen, J., Zeeman, G., Fayyad, M. and Lettinga, G., 2005, Effect of SRT and temperature on biological conversions and the related scum-forming potential, Water Res., 39 (12), 2475–2482.

Joubert, W.A. and Britz, T.J., 1996, The effect of pH and temperature manipulation on metabolite composition during acidogenesis in a hybrid anaerobic digester, Appl. Microbiol. Biotechnol., 24, 253–258.

Karadag, D., Köroʇlu, O.E., Ozkaya, B. and Cakmakci, M., 2014, A review on anaerobic biofilm reactors for the treatment of dairy industry wastewater, Process Biochem., 50 (2).

Kisaalita, W.S., Pinder, K.L. and Lo, K. V., 1987, Acidogenic fermentation of lactose, Biotechnol. Bioeng., 33, 623–630.

Kurnianto, R.W., 2019, Evaluasi Proses Peruraian Anaerobik Limbah Dissolved Air Flotation Dari Pabrik Susu Dengan Perlakuan Awal Saponifikasi, Gadjah Mada University.

Kurnianto, R.W., Cahyono, R.B. and Budhijanto, W., 2019, Evaluation of inoculum source and saponification pre-treatment in anaerobic digestion of dissolved air flotation waste from dairy industry, AIP Conf. Proc. 2085(1) 020009.

Masse, L., Massé, D.I. and Kennedy, K.J., 2003, Effect of hydrolysis pretreatment on fat degradation during anaerobic digestion of slaughterhouse wastewater, Process Biochem., 38 (9), 1365–1372.

Ramadhani, L.I., Damayanti, S.I., Sudibyo, H. and Budhijanto, W., 2017, Kinetics of anaerobic digestion of palm oil mill effluent (POME) in double stage batch reactor with recirculation and fluidization of microbial immobilization media, IOP Conf. Ser. Mater. Sci. Eng., IOP Publishing Ltd.

Rasit, N., Idris, A., Harun, R. and Wan Ab Karim Ghani, W.A., 2015, Effects of lipid inhibition on biogas production of anaerobic digestion from oily effluents and sludges: An overview, Renew. Sustain. Energy Rev., Elsevier, 45, 351–358.

Statistik, B.P., 2019, Produksi Susu Segar menurut Provinsi, 2009-2018, available at: https://www.bps.go.id/linkTableDinamis/view/id/1083 (accessed 22 January 2019).

Vavilin, V.A., Rytov, S. V. and Lokshina, L.Y., 1996, A description of hydrolysis kinetics in anaerobic degradation of particulate organic matter, Bioresour. Technol., 56 (2–3), 229–237.

Walker, M., Zhang, Y., Heaven, S. and Banks, C., 2009, Potential errors in the quantitative evaluation of biogas production in anaerobic digestion processes, Bioresour. Technol., 100 (24), 6339–6346.

Yu, H.-Q. and Fang, H.H.P., 2002, Acidogenesis of dairy wastewater at various pH levels, Water Sci. Technol., 145 (10), 201–206.

Zhang, Q., Hu, J. and Lee, D.J., 2016, Biogas from anaerobic digestion processes: Research updates, Renew. Energy, 98, 108–119.

Zoetemeyer, R.J., van den Heuvel, J.C. and Cohen, A., 1982, pH influence on acidogenic dissimilation of glucose in an anaerobic digestor, Water Res., 16, 303–311.



DOI: https://doi.org/10.22146/jrekpros.48959

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