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J Rintala

Publications and source records attributed to J Rintala.

At least 19 recordsLinked to original sources
PubMed2006

Anaerobic on-site treatment of kitchen waste in combination with black water in UASB-septic tanks at low temperatures.

Anaerobic on-site treatment of a mixture of black water and kitchen waste (BWKW) was studied using two-phased upflow anaerobic sludge blanket (UASB) septic tanks at the low temperatures of 20 and 10 degrees C. Black water (BW) was also treated alone as reference. The two-phased UASB-septic tanks removed over 95% of total suspended solids (TSS) and 90% of total chemical oxygen demand (COD(t)) from both BWKW (effluent COD(t) 171-199mg/l) and BW (effluent COD(t) 92-100mg/l). Also, little dissolved COD (COD(dis)) was left in the final effluents (BW 48-70mg/l; BWKW 110-113mg/l). Part of total nitrogen (N(tot)) was removed (BW 18% and BWKW 40%) and especially at 20 degrees C ammonification was efficient. A two-phased process was required to obtain the high removals with BWKW at 10 degrees C, while with BW a single-phased process may have sufficed even at 10 degrees C. BWKW also produced more methane than BW alone. Sludge in phases 1 of BW and BWKW treatment was not completely stabilised after 198d of operation.

Anaerobiosis↗
PubMed2006

Early short-term platelet-derived growth factor inhibition prevents the development of chronic allograft nephropathy in experimental rat kidney transplantation.

Chronic allograft nephropathy (CAN) remains the primary reason for late allograft loss in kidney transplantation. Platelet-derived growth factor (PDGF) is a major mitogen mediating mesenchymal cell proliferation in CAN. When administered continuously the PDGF receptor tyrosine kinase inhibitor imatinib prevents the development of CAN and restores kidney function in experimental kidney transplantation. Herein we investigated whether early short-term imatinib treatment prevented CAN. Kidney transplantations were performed from DA to WF rats and syngenic controls were done between DA rats. Allograft recipients were immunosuppressed with cyclosporine (CsA; 1.5 mg/kg/d sc). One group of allografts was also treated with imatinib (10 mg/kg/d po). Serum creatinine levels were measured once a week. Grafts were harvested 90 days after transplantation for histology and immunohistochemistry (PDGF-AA, -BB, PDGFR-alpha, -beta). Histological changes were scored according to the Chronic Allograft Damage Index (CADI). Among syngenic grafts, no signs of CAN were observed, namely, CADI 0.3 +/- 0.2 (mean +/- SEM). Control allografts showed moderate to intense chronic changes, CADI 6.5 +/- 1.3. Early short-term imatinib treatment significantly prevented the development of CAN compared with control allografts. Only a few histological changes were seen, namely, CADI 3.3 +/- 1.4. Compared with control allografts PDGF ligand and receptor induction was significantly inhibited by imatinib to nearly the same level as in syngenic grafts. Creatinine values of imatinib-treated allografts were also lower than control allografts. Our results demonstrated that early short-term imatinib treatment significantly prevented CAN. This indicated that early PDGF induction has an important role in the pathogenesis of CAN.

Animals↗
PubMed2006

Biomass characterization of laboratory-scale thermophilic-mesophilic wastewater treatment processes.

Two thermophilic-mesophilic wastewater treatment processes, one as the combination of the thermophilic activated sludge process (ASP), followed by the mesophilic ASP and the other as thermophilic suspended carrier biofilm process (SCBP), followed by the mesophilic ASP, were used to study sludge characteristics and floc formation. Thermophilic bacteria in both ASP and SCBP were able to form flocs, which were <50 microm in size and had a weak structure and irregular shape. Flocs in both the mesophilic ASPs were larger in size (50-500 microm) and had more compact structures. Filamentous bacteria played an important role in both the thermophilic and mesophilic processes by forming bridges between small flocs. Both thermophilic processes showed a high density of dispersed particles, such as free bacteria. When hydraulic retention time (HRT) was decreased the biofilm was retained in the thermophilic SCBP better than the flocs in the thermophilic ASP. The mesophilic ASPs efficiently removed dispersed particles originating from the thermophilic processes.

Anaerobiosis↗
PubMed2006

Co-digestion of manure and biowaste according to the EC animal by-products regulation and Finnish national regulations.

The objective of this study was to compare methane production and characteristics of digested material in anaerobic digestion concepts according to the Animal By-Products Regulation (ABP-Regulation) of the EC (hygienisation of biowaste for 1 hour at 70 degrees C, particle size < 12 mm) and Finnish national regulations (treatment temperature 55 degrees C, feeding interval 24 h, hydraulic retention time (HRT) 20 d, particle size < 40 mm) and with small variations in treatment methods for treating manure and biowaste. Moreover, the survival of three different salmonella bacteria in these processes was studied. Hygienisation of biowaste prior to digestion at 35 degrees C enhanced methane production by 14-18% compared to similar treatment without hygienisation. The differences in treatment temperature, HRT and hygienisation of biowaste prior to digestion did not significantly affect the characteristics of digested material. The concepts according to the ABP-Regulation and Finnish national regulations were effective in destroying salmonella bacteria to an undetectable level.

Federal Government↗
PubMed2006

Anaerobic on-site black water and kitchen waste treatment using UASB-septic tanks at low temperatures.

Anaerobic on-site treatment of black water (BW) and a mixture of black water and kitchen waste (BWKW) was studied in a two-phased upflow anaerobic sludge blanket septic tank (UASBst) at 10-20 degrees C. The processes were fed either continuously or discontinuously (twice per weekday). Moreover, BWKW was post-treated for nitrogen removal in an intermittently aerated moving bed biofilm reactor (MBBR) at 20 degrees C. Removal of total chemical oxygen demand (COD1) was efficient at minimum 90% with all three UASBst at all temperatures. Removal of dissolved COD (CODdis) was also high at approx. 70% with continuously fed BW and discontinuously fed BWKW, while with discontinuous BW feeding it was 20%. Temperature decrease had little effect on COD removals, though the need for phase 2 increased with decreasing temperature, especially with BWKW. Post-treatment of BWKW in MBBR resulted in approx. 50% nitrogen removal, but suffered from lack of carbon for denitrification. With carbon addition, removal of ca. 83% was achieved.

Anaerobiosis↗
PubMed2005

Comparative study of laboratory-scale thermophilic and mesophilic activated sludge processes.

Laboratory-scale mesophilic (20-35 degrees C) and thermophilic (55 degrees C) activated sludge processes (ASPs) treating diluted molasses wastewater were compared in effluent quality, removal of different COD fractions, sludge yield, floc size, and sludge settleability. The effect of polyaluminium chloride (PAC) with high cationic charge on sludge settleability and effluent quality was also studied. In the ASPs, the hydraulic retention time was 12h in both processes, corresponding to a volumetric loading rate of 3.2+/-1.0 kg COD(filt) m(-3)d(-1). The mesophilic ASP gave 79+/-18% and 90+/-2% and the thermophilic ASP gave 50+/-6% and 67+/-11% total COD (COD(tot)) and GF/A-filtered COD (COD(filt)) removals, respectively. The higher COD values in the thermophilic effluent were due to dispersed particles, such as free bacteria, measured as colloidal COD (COD(col)=difference between soluble COD (COD(sol)) and COD(filt)). Both ASPs gave high (90%) COD(sol) removals. Aeration (24-h) of the thermophilic ASP effluent at 35 degrees C reduced the density of the free bacteria by half, which was also measured as 90% COD(col) removal. Post-aeration of thermophilic effluent at 55 degrees C had no influence either on the density of free bacteria or on the COD(col) values. The use of PAC did not increase COD(tot) or COD(filt) removals in either process, but reduced the mesophilic and increased the thermophilic sludge volume index values.

Aluminum Hydroxide↗
PubMed2003

Comparison of laboratory-scale thermophilic biofilm and activated sludge processes integrated with a mesophilic activated sludge process.

A combined thermophilic-mesophilic wastewater treatment was studied using a laboratory-scale thermophilic activated sludge process (ASP) followed by mesophilic ASP or a thermophilic suspended carrier biofilm process (SCBP) followed by mesophilic ASP, both systems treating diluted molasses (dilution factor 1:500 corresponding GF/A-filtered COD (COD(filt)) of 1900+/-190 mgl(-1)). With hydraulic retention times (HRTs) of 12-18 h the thermophilic ASP and thermophilic SCBP removed 60+/-13% and 62+/-7% of COD(filt), respectively, with HRT of 8 h the removals were 48+/-1% and 69+/-4%. The sludge volume index (SVI) was notably lower in the thermophilic SCBP (measured from suspended sludge) than in the thermophilic ASP. Under the lowest HRT the mesophilic ASP gave better performance (as SVI, COD(filt), and COD(tot) removals) after the thermophilic SCBP than after the thermophilic ASP. Measured sludge yields were low (less than 0.1 kg suspended solids (SS) kg COD(filt removed)(-1)) in all processes. Both thermophilic treatments removed 80-85% of soluble COD (COD(sol)) whereas suspended COD (COD(susp)) and colloidal COD (COD(col)) were increased. Both mesophilic post-treatments removed all COD(col) and most of the COD(susp) from the thermophilic effluents. In conclusion, combined thermophilic-mesophilic treatment appeared to be easily operable and produced high effluent quality.

Aerobiosis↗
PubMed2003

The methane production of poultry slaughtering residues and effects of pre-treatments on the methane production of poultry feather.

The biological methane production rate and yield of different poultry slaughtering residues were studied. Poultry offal, blood, and bonemeal were rich in proteins and lipids and showed high methane yields, 0.7-0.9, 0.5, and 0.6-0.7 m3 kg(-1) volatile solids(added), respectively (270-340, 100, and 150-170 m3 ton(-1) wet weight). Blood and bonemeal produced methane rapidly, whereas the methane production of offal was more delayed probably due to long-chain fatty acid inhibition. The length of delay depended on the source and concentration of inoculum and incubation temperature, sewage sludge at 35 degrees C having the shortest delay of a few days, while granular sludge did not produce methane within 94 days of incubation. Feather showed a somewhat lower methane yield, 0.21 m3 kg(-1) volatile solids(added) (50 m3 ton(-1) wet weight). Combined thermal (120 degrees C, 5 min) and enzymatic (commercial alkaline endopeptidase, 2-10 g l(-1)) pre-treatments increased its methane yield by 37 to 51%. Thermal (70-120 degrees C, 5-60 min), chemical (NaOH 2-10 g l(-1), 2-24 h), and enzymatic pre-treatments were less effective, with methane yield increasing by 5 to 32%. Based on the present results, anaerobic digestion of the studied poultry slaughtering residues appears a promising possibility because of the high methane yield and nitrogen content of these residues (8 to 14% N of total solids), whereas pre-treatments were shown to improve the methane production of feather.

Abattoirs↗
PubMed2003

Evaluation of the current status of operating and closed landfills in Russia, Finland and Ireland with regard to water pollution and methane emission.

The annual production of municipal solid wastes (MSW) in Russia, Finland and Ireland in the late 1990s accounts for 37.5, 2.5 and 2.05 min. tonnes or 252, 488 and 566 kg per capita, respectively. 96.5, 64 and 91% of these wastes (for Russia, Finland and Ireland, correspondingly) are currently disposed of via landfilling. However, nowadays, MSW management in these countries is undergoing drastic changes (source separation, closure of old landfills, reduction of the number of landfills etc.) forced by recent legislation set by the European Union and Russian authorities. This paper evaluates the current status of MSW landfills, as well as information on current leachate and methane emissions in the three above mentioned countries. Landfill leachates are highly variable in each country and between different countries due to different rainfall and climatic conditions and also due to poor landfill top insulation/cover. Leachates in poorly structured landfills are very dilute, whereas leachates with total COD and nitrogen contents as high as 33,700 mg COD/l and 4,030 mg N/l, respectively, have been detected from state-of-the-art sites. Currently, on-site treatment of leachates exists at only a few landfills in Russia, Finland and Ireland but this situation will be considerably improved during the next years. The annual methane emissions from landfills are estimated as 500-900 and 77 ktonnes for Russia and Finland, respectively. Recent estimates from Ireland suggest an annual landfill methane emission of c. 2.1 Mt CO2 equivalent. Several systems of methane recovery have been developed in all three countries and these are currently in different stages of implementation.

Environmental Monitoring↗
PubMed2003

The analysis of methods for measurement of methane oxidation in landfills.

Landfills and dumps are important sources of atmospheric methane. There is no generally accepted estimate of the influence of methane oxidation on landfill methane emissions. The present work aimed to analyse different methods for the investigation of methane emission and oxidation in methane-producing environments (wetlands, landfills, sludge checks), and to develop the precise procedure for the landfills. The combination of geochemical and microbiological methods to estimate and monitor the oxidation and emission of methane in landfills during different seasons is proposed. It includes the measurements, both on the surface and at different depths (up to 1 m) of landfill ground of the following parameters: (1) concentrations of methane, carbon dioxide and oxygen; (2) quantity of 13C isotope in gas samples; (3) methane-oxidation activity of landfill grounds assayed with two different methods: (a) in conditions of no moisture or substrate limitations, and (b) in conditions with a minimal deviation to in situ conditions; (4) the density of methanotrophic microbial population.

Carbon Dioxide↗
PubMed2003

A distributed model of solid waste anaerobic digestion: sensitivity analysis.

A distributed model of anaerobic digestion of solid waste was developed to describe the balance between the rates of polymer hydrolysis and methanogenesis during the anaerobic conversion of rich and lean wastes in batch and continuous-flow reactors. Waste, volatile fatty acids (VFAs), methanogenic biomass and sodium concentrations are the model variables. Diffusion and advection of VFAs inhibiting both polymer hydrolysis and methanogenesis were considered. A sensitivity analysis by changing the key model parameter values was carried out. The model simulations showed that the effective distance between the areas of hydrolysis/acidogenesis and methanogenesis is very important. An initial spatial separation of rich waste and inoculum enhances the methane production and waste degradation at high waste loading if relatively low VFA diffusion into the methanogenic area is taking place. When both hydrolysis and methanogenesis are strongly inhibited by high levels of VFA, fluctuations in biomass concentration are thought to be responsible for initiating the expansion of methanogenic area over the reactor space.

Bacteria, Anaerobic↗
PubMed2002

Anaerobic digestion of organic solid poultry slaughterhouse waste--a review.

This work reviews the potential of anaerobic digestion for material recovery and energy production from poultry slaughtering by-products and wastes. First, we describe and quantify organic solid by-products and wastes produced in poultry farming and poultry slaughterhouses and discuss their recovery and disposal options. Then we review certain fundamental aspects of anaerobic digestion considered important for the digestion of solid slaughterhouse wastes. Finally, we present an overview of the future potential and current experience of the anaerobic digestion treatment of these materials.

Abattoirs↗
PubMed2002

Chronic lithium downregulates cyclooxygenase-2 activity and prostaglandin E(2) concentration in rat brain.

Rats treated with lithium chloride for 6 weeks have been reported to demonstrate reduced turnover of arachidonic acid (AA) in brain phospholipids, and decreases in mRNA and protein levels, and enzyme activity, of AA-selective cytosolic phospholipase A(2)(cPLA(2)). We now report that chronic lithium administration to rats significantly reduced the brain protein level and enzyme activity of cyclooxygenase-2 (COX-2), without affecting COX-2 mRNA. Lithium also reduced the brain concentration of prostaglandin E(2) (PGE(2)), a bioactive product of AA formed via the COX reaction. COX-1 and the Ca(2+)-independent iPLA(2) (type VI) were unaffected by lithium. These and prior results indicate that lithium targets a part of the AA cascade that involves cPLA(2) and COX-2. This effect may contribute to lithium's therapeutic action in bipolar disorder.

Animals↗
PubMed2002

Comparison of activated sludge processes at different temperatures: 35 degrees C, 27-55 degrees C, and 55 degrees C.

The performance of mesophilic (35 degrees C; referred to as R1) and thermophilic (55 degrees C; R3) laboratory activated sludge processes (ASPs) as well as ASP with a fluctuating temperature (27-56 degrees C; R2) was compared. During the 124-day runs, in R1 and R3 hydraulic retention time was gradually reduced from 18 h to 3 h, corresponding to an increase in volumetric loading rate from 2 to 10 kg soluble COD m(-3) d(-1); in R2 hydraulic retention time was gradually reduced from 18 to 4.5 h, corresponding to an increase in volumetric loading rate from 2 to 7.5 kg soluble COD m(-3) d(-1). R1 removed on average 85% of soluble COD (GF50-filtered) that was approximately 10% more than R3. In R2 SCOD removal was dependent on the operating temperature, being comparable to R1 and R3 at respective temperature. However, the COD for 0.45 microm-filtered (bacteria-free) effluent samples was lower for R3 than for R1, indicating the role of free bacteria on effluent quality. Furthermore, 24 h post-aeration of R3 effluent at 35 degrees C decreased SCOD (GF50-filtrated) markedly (43% removal), whereas at 55 degrees C no SCOD removal occurred, which suggest mesophilic post-treatment ability to remove thermophilically recalcitrant matter or, more probably, the ability of free bacteria to aggregate more efficiently under lower temperatures. The results indicate that temperature may not be as crucial a factor in high temperature biological wastewater treatment as previously believed. On the other hand, in thermophilic ASP the importance of solids separation is emphasized.

Bioreactors↗
PubMed2002

A comparative analysis of a balance between the rates of polymer hydrolysis and acetoclastic methanogenesis during anaerobic digestion of solid waste.

A distributed model of anaerobic digestion of solid waste was developed. Waste, volatile fatty acids (VFA), methanogenic biomass and methane concentrations were the model variables. A system of parabolic partial differential equations in the one space variable and time with slab, cylindrical or spherical symmetry of the problem was solved numerically. Diffusion of VFA inhibiting both polymer hydrolysis and acetoclastic methanogenesis was taken into account. The model showed that concentration waves of methanogenic biomass and VFA propagated over reaction space. Diffusion-based "acceleration" of methane production in the reactor was possible when intensity of VFA utilisation in the methanogenic area was sufficient for complete digestion of incoming VFA. Otherwise, methanogenic area propagation would be suppressed. Optimum conditions for the solid waste digestion can be reached at low mass transfer at the beginning and at high mass transfer when methanogenic population increases. If the initial methanogenic biomass was localised at the centre of the reactor, the total reaction time was shorter as compared to the case when the initial biomass was uniformly distributed over the reactor volume. In the last case, there was no concentration wave propagation.

Bacteria, Anaerobic↗
PubMed2002

Co-digestion of energy crops and industrial confectionery by-products with cow manure: batch-scale and farm-scale evaluation.

The possible co-digestion of energy crops and industrial confectionery by-products with cow manure was evaluated firstly, through long-term batch experiments and secondly, in a farm-scale digester. In batch assays, digestion with mesophilically digested cow manure as inoculum resulted in specific methane yields (m3 kg(-1) VS added waste) of 0.35 for grass hay (particle size <1.0 cm); 0.26 for oats (0.5 cm) and 0.21 for clover (2.0 cm) harvested at vegetative stage and 0.14 (2.0 cm) for clover harvested at flowering stage. Specific methane yields (m3 kg(-1) VS added waste) for confectionery by-products were 0.37 for chocolate, 0.39 for black candy and 0.32 for confectionery raw material. Out the three particle sizes (2.0, 1.0 and 0.5 cm) tested, particle size of 1.0 cm was found ideal for digestion of grass hay and clover while, particle size reduction did not influence methane production from oats. Stage of the crop influenced the methane yields, with clover harvested at vegetative stage yielding 33% higher methane than when harvested at flowering stage. An approximate 60% enhancement in methane yield was noticed with the co-digestion of industrial confectionery wastes with cow manure in a full-scale farm digester.

Animal Feed↗
PubMed2001

Dose-dependent decrease in glial fibrillary acidic protein-immunoreactivity in rat cerebellum after lifelong ethanol consumption.

The effects of aging and lifelong ethanol consumption on astrocytic morphology and glial fibrillary acidic protein-immunoreactivity (GFAP-IR) in the cerebellar vermis obtained from ethanol-preferring Alko, Alcohol (AA) rats were analyzed by using computer-assisted image analysis. The ethanol-consuming animals (both male and female) were given ethanol (10%-12%, vol./vol.) as the only available fluid for 21 months (3-24 months), whereas the young (3 months) and the old (24 months) controls received water. In the male rats, but not in the female rats, an age-related decrease in GFAP-IR was found in folia II, VII, and X of the molecular layer, and in turn, an age-related increase was found in folium X of the granular layer, indicating opposite changes in GFAP-IR for male rats due to aging in adjacent brain regions. In the female rats, 21 months of daily average ethanol consumption of 6.6 g/kg resulted in decreased GFAP-IR in folium VII of the molecular layer, and the decrease in cerebellar GFAP-IR correlated with the average daily ethanol intake (r=-.886, P=.019) when folia II, IV, VII, and X were analyzed together. No effect of ethanol on GFAP-IR was detected in the granular layer or in the central white matter of the female rats. There was no change in GFAP-IR in any of the three cerebellar layers of the male rats with average daily ethanol consumption of 3.2 g/kg. These results indicate that the Bergmann glial fibers are the GFAP-expressing structures of the cerebellum most sensitive to moderate-to-heavy chronic ethanol exposure and that this effect is dose dependent.

Age Factors↗