hồ sơ cá nhân

hồ sơ cá nhân

THE 28 CONFERENCE

OF THE FEDERATION OF ENGINEERING ORGANIZATIONS

CAFEO 28 HANOI VIETNAM, 30 TH NOV - 2 ND DEC., 2010

TITLE:

BIOHYDROGEN PRODUCTION BY ANAEROBIC BAFFLED REACTOR FROM WASTEWATER OF SEASONING SAUCE FACTORY

AUTHOR(S)’

NAME(S):

Mr.Verapat Rittapirom* and

Associate Professor, Doctor Thares Srisatit**

ORGANIZATION

& DESIGNATION:

Department of Environmental Engineering, Chulalongkorn University, Bangkok Thailand

ADDRESS:

359/133 Soi 3 Moo 5 Sub-district Salaya district Puttamonthon Province Nakhonprathom 73170*

Department of Environmental Engineering, Chulalongkorn University, Bangkok Thailand.**

081-9272352**

EMAIL: jimmy_jom23@hotmail.com*

thares.S@chula.ac.th**

Verapat Rittapirom

BIOHYDROGEN PRODUCTION BY ANAEROBIC BAFFLED

REACTOR FROM WASTEWATER OF SEASONING SAUCE FACTORY

Verapat Rittapirom* and Thares Srisatit**

Department of Environmental Engineering, Chulalongkorn University,

Bangkok Thailand, jimmy_jom23@hotmail.com*

thares.S@chula.ac.th**

ABSTRACT

Hydrogen power has long been heralded as the renewable energy source of the future because of its cost effectiveness and low environmental impact So, this research it is very interested in hydrogen (H2) gas production by using a three chambered anaerobic baffled reactor (ABR) from wastewater of seasoning sauce factory (the average total COD value was found to be around 14,000-18,000 mg/l and pH~3-4) The reactor was inoculated with thermally pretreated anaerobic sludge (80

°C and 110 °C 30 minutes) compare with non pretreated and operated with constant hydraulic retention time (HRT) of 5 days at room temperature H2 is generated under the acidogenesis and acetogenesis phase before transforming to be methane (CH4) While, ABR operation found that inoculated with thermally pretreated at 110°C promoted % hydrogen production in biogas with initial pH 5 showed higher H2

production of 39-41% of the maximum were reported The ABR has the potential to provide a higher efficiency at higher loading rates and be applicable for extreme environmental conditions and inhibitory compounds

INTRODUCTION

Rising oil prices, finite fossil fuel reserves, environmental degradation, and concerns about looming climatic changes are driving a concerted search for renewable energy sources A large fraction of current fossil fuel consumption is due to the transportation sector which relies almost exclusively on the use of liquid fossil fuels Partial or complete replacement of presently used carburants, gasoline or diesel, with

a renewable energy carrier is thus key to averting or reducing the impending crisis (Hallenbeck, 2009) The need for alternative energy sources has increased in recent years, due to rapid depletion of fossil fuels Direct utilization of fossil fuels results in considerable Environmental problems due to CO2, SOX , NOX emissions causing air pollution and global warming Hydrogen gas is a clean fuel with no CO2 emissions and can easily be used in fuel cells for electricity generation Besides, hydrogen has a high energy content of 122 kJ/g, which is 2.75 times greater than hydrocarbon fuels Hydrogen is considered as the major energy carrier of the future Biomass and water can be used as renewable resources for hydrogen gas production (Argun et al., 2008) Bioprocesses have been given special attention for hydrogen production in the last thirty years due to operation under mild conditions (25–35 oC, 1 atm), the production

of bio-hydrogen from renewable sources such as biomass has considerable advantages over other alternatives, Biohydrogen production can be realized by anaerobic (dark fermentation) microorganisms using carbohydrate rich biomass as a renewable resource (Kapdan and Kagi, 2006)

This is an experimental research in laboratory, initial screening and optimize

of initial pH that significantly influence on hydrogen production from wastewater

of seasoning sauce factory in a continuous bio-hydrogen process using anaerobic mixed cultures in the Anaerobic Baffled Reactor (ABR) to study the performance of

H production and optimum pH condition on H production All of experimental

study the microbial for H2 production by temperature control during fermentation for

3 point i.e at the worst case (%minimum hydrogen production), medium case (%medium hydrogen production) and best case (the optimum which %maximum hydrogen production) using Gas Chromatography-TCD detector(Thermo Finnigan)

MATERIALS AND METHODS

1 Anaerobic Baffled Reactor (ABR)

The ABR consisted of a rectangular, Plexiglas reactor (inside dimensions: length = 42 cm, height = 35 cm, width = 12 cm) with active volume about 12 L which divided into three compartments Round openings with a diameter of 2.5 cm from the backside of the Plexiglas sheets separated the compartments These openings were placed at the bottom to create sufficient contact between biomass and substrate The flow over the horizontal plane of the reactor was reversed once a week A weekly change in flow direction was chosen to prevent a pH drop due to VFA build up in the initial compartment and to prevent unequal biomass levels due to anticipated biomass migration between compartments The samples will be withdraw from the ABR reactor A structure and schematic of the lab-scale of ABR used in this study is presented in Figure 1

Fig 1 Schematic configuration of lab-scale ABR

2 Material

- 3 model of lab-scale ABR (12 L active volume follow fig 1)

- 3 of Metering pump

- 3 of Counter gas by using water displacement

- 6 of 15 L Plastic tank

3.Feed wastewater and mix cultures inoculum preparation

Seasoning sauce factory wastewater, which was used in this investigation, was obtained from a local processing plant Bangpu Industrial Estate, Samut Prakan province, Thailand The raw wastewater contained COD of 14,000–18,000 mg/L,

Effluent Tank

Total gas Measurement

Feeding

Tank

pH meter

Gas sampling

1

3

4

5

BOD of 6,000–10,000 mg/L, total solids (TS) of 10,260-10,752 mg/L, total suspended solids(TSS) of 3,400–4,000 mg/L, total nitrogen (TN) of 14 mg/L, total phosphorus (TP) of 9.68 mg/L ,total volatile fatty acid(VFA) of 1483 mg/L and had a pH of 3.7– 4.0

The reactor was initially seeded with flocculent anaerobic sewage sludge collected from one of the UASB reactor located from fruit juice industry, Nakhonprathom, Thailand and was then introduced uniformly into all three compartments of the ABR Each 4 L compartment contained 1.2 L sludge The microorganism seed was heat treated at various temperatures ranging from 80ºC to

110 ºC for 30 minutes to inactivate the non-spore forming methanogens The heat-treated inoculum (HTI) was spore stained The harvested spore forming acitogens are used for producing hydrogen from seasoning sauce wastewater

4 Analytical methods

COD, BOD, TSS, TS, pH, and oxidation-reduction potential (ORP) were measured according to standard methods(APHA, 1995) The biogas constituents (H2,

CO2 and CH4) were analyzed by a gas chromatogram (GC, Thermo Finnigan) with a thermal conductivity detector (TCD) and shin carbon column packed The concentrations of VFAs were measured using another gas chromatograph(GC, Agilent 4890D) with a flame ionization detector (FID)and a2 m stainless column packed with Porapak GDX103 (60/80 mesh).COD, pH, biogas volume and ORP were measured or monitored daily.BOD, VFAs, TS, TSS and biogas yield were measured once every 5 days

5 Operation of anaerobic baffled reactor

Barber and Stuckey (1998) had suggested to initially use long detention time (80 h) to startup the ABR and to reduce it in stepwise fashion while maintaining a constant incoming substrate concentration It provides greater reactor stability and superior reactor performance

The investigation was carried out with a constant hydraulic retention time (HRT) and varying influent COD concentration The ABR was fed with different concentration diluted seasoning sauce factory wastewater at constant HRT value corresponding to organic loading rate of 1 and 2 kgCOD/m3-d, respectively The experiment in this study consisted of two subsequent [A = initial pH 3-4 and B = initial pH 5] (shown in Table 1)

Table 1 The operation parameter of ABR start up

The loading rates were only increased when steady state conditions were obtained for the existing loading condition In general, a steady state condition was believed to have been reached when a relatively small variation in the levels of determinants of the final effluent for two different samples The ABR reactor was

Operation

stage

HRT (days) T (°C) Influent pH value

Influent COD concentration (mg/L)

OLR (kgCOD/ m3d)

1st stage

2nd stage

5

5

Room temp

Room temp

A and B

A and B

5,000 11,000

1

2

operated continuously until reached constant COD removal during the start-up period Then it was operated with increasing COD concentrations from 5,000– 5,200 mg/L to 9,000–11,000 mg/L, When effluent COD in the bioreactor became constant, the samples were collected and subjected to the analysis of the following parameters, i.e feed and effluent COD, effluent total volatile acid; reactor pH, gas production and composition

The experiment in this study consisted of two subsequent [A = initial pH 3-4 and B = initial pH 5], each subsequent were as follow:ABR1 non-treated sludge.ABR2 thermally pretreated anaerobic sludge 80 °C for 30 minutes and ABR3 thermally pretreated anaerobic sludge 110 °C for 30 minutes) by ratio between anaerobic sludge : wastewater = 30% : 70% [shown in Fig 2]

RESULTS AND DISCUSSION

1 COD removal

Feeding was started at a soluble COD feed concentration of 5,000 mg/L at HRT of 5 days (OLR = 1 kg COD/m3d) (Fig 3A and 3B).From the very decreasing COD removal effluent were in the range of 40-50% of influent COD and after 15 days

of startup, feeding soluble COD of 11,000 mg/L until effluent COD of both initial pH 3-4 and 5 have stability of the process After that operation process was started at 14,000-18,000 mg/l COD concentration of raw seasoning sauce wastewater from data

in Fig 3A and 3B at HRT of 5 days[day 36-60]

Wastewater [A and B]

Parameters analysis

Fig 2 Experimental procedure

Sludge : Wastewater ratio = 30% : 70%

Biogas analysis Effluent analysis

- Volume of biogas production

- % Hydrogen in biogas

- COD - BOD

- VFAs - TS & TSS

It was operated from day 33 to day 55 at Fig 3A, Effluent COD of ABR1, ABR2 and ABR3 were 11,979 12,301 and 12,697 mg/L, respectively.It shown that

the rate of COD removal were declined from the day 48 to the day 55 and in Fig 3B

shown that COD effluent was declined at the day 34 to the day 60 , Effluent COD of

ABR1, ABR2 and ABR3 were 9084 10,612 and 10,723 mg/L, respectively So, All of

COD removal efficiency of Initial pH 5 was generally better than Initial pH 3-4

condition in Table 2

HRT

[Days]

Seed

conditions

Influent COD [mg/L]

Effluent COD[mg/L]

% COD removal

Effluent COD[mg/L]

% COD removal

A

0 5000

10000

15000

20000

Days

B

0 5000 10000 15000 20000

Days

Fig 3 ABR performance of influent and effluent COD concentration

Table 2 COD removal with 5 days HRT

2 Variation of VFA concentrations

The profiles of VFAs in different initial pH and microorganism seed conditions are depicted in Fig 4.It shown that VFAs was generated immediately of acidogenic degradation of seasoning sauce wastewater in the ABR

It is inferred from the Figures 4 that during the initial days, VFAs concentration increased rapidly at the beginning of the operate system [at the day 3- the day 12] and after that VFAs concentration declined until at 2000 mg/L at the day

24 Production of various volatile fatty acids in the acitogenic stage may be the reason for increasing VFAs concentration in the earlier days (Shin, Youn and Kim, 2004) The reduction in VFAs may be due to their conversion into gaseous products

3 Biogas and %hydrogen productivity

Biogas productivity per gm COD removed at the different initial pH [5A initial pH 3-4 and 5B initial pH 5] are shown in Fig 5A and 5B.Initialy Cumulative gas production of initial pH 3-4 was lower than pH 5 (Fig 5) The reason for low gas production because of the fermentation are not arrive at acitogenesis and low pH of wastewater Some fraction of the gas produced solubilized in reactor effluent and escaped from collection At steady state of fig 5A, average biogas productions in case

of ABR1, ABR2 and ABR3 of 5 days HRTs were 34.88, 33.34 and 28.29 ml/g COD removed, respectively At steady state of fig 5B, average biogas productions in case

Initail pH 3-4[raw wastewater]

0 2000 4000 6000 8000 10000

Days

Initial pH 5

0 2000

4000

6000

8000

Days

Fig.4 VFA profiles in different initial pH

of ABR1, ABR2 and ABR3 of 5 days HRTs were 26.92, 29.78 and 26.11 ml/g COD removed, respectively

The high %hydrogen production by ABR in this study could be explained on the basis of least two arguments: [i] has optimum initial pH values was 5.At this pH, both methanogenesis and solventogenesis can be avoided or minimized [both processes would decrease %hydrogen production].In this study, it seems that the initial pH 5 in this study was higher than initial pH 3-4[raw wastewater]Fig.6;[ii] Inoculated with sludge heat-treated at 110 °C for 30 minutes has been reported that the acidogenesis hydrogen-producing consortia are enriched in Clostridium, most being heat resistant

0 10 20 30 40 50

Fig 6 Performance of % Hydrogen production in biogas

B

0 20 40 60 80 100

Days

A

0 20 40 60 80 100 120

Fig.5 Biogas production per gm COD removal in different initial pH

The maximum amount of percentage hydrogen in biogas was produced at initial pH 5 among investigated pH values shown in Fig 6 at pH 5 the maximum

%hydrogen production of ABR3, ABR2 and ABR1 reached 39-41%, 26-31% and 23-27%, respectively

CONCLUSION

Both the initial pH [pH 3-4 and pH 5] using the organic fraction of seasoning sauce wastewater seems to be attractive for hydrogen generation, Cause pH conditions effect to acidogenesis process but initial pH 5 experiment was considered better than initial pH 3-4,that enhancing percentage hydrogen production after bacterial stress by using dry heat at 110 °C 30 minutes

REFERANCE

Argun, H., Kargi, F., Kaptan, I.K and Oztekin, R.2008.Biohydrogen production by dark fermentation of wheat powder solution: Effects of C/N and C/P ratio on

hydrogen yield and formation rate Int J Hydrogen Energy, 33: 1813 – 1819

APHA.1998 American Public Health Association Standard Methods for the

Examination of Water and Waste Water 20th ed Washington, DC: APHA and American Water Works Association and Water Environment Federation Hallenbeck, P.C.2009 Fermentative hydrogen production: Principles, progress, and

prognosis Int J Hydrogen Energy,34 : 7379-7381

Kapdan, I.K and Kargi, F.2006.Bio-hydrogen production from waste materials

Enzyme and Microbial Technology , 38 : 569–582

Shin, H.S., Youn, J.H and Kim, S.H.2004.Hydrogen Production from Food

Waste in Anaerobic Mesophilic and Thermophilic Acidogenesis International Journal of Hydrogen Energy, 29: 1355 – 1363