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Integrated laboratory system consisted of three stages - activated sludge reactor, biofilter and subsurface vertical flow wetland was used to treat two types of wastewaters differed in their generation and pollution. Wastewaters from a pig farm as well as from a landfill site for domestic wastes were used in the experiments. The BOD/COD ratio of the wastewaters from a pig farm and from the landfill leachate was 0.5 and 0.07, respectively. In the first stage of the integrated system was achieved COD removal (48 % for the piggery wastewater for 3 days and 62.3 % for the landfill leachate after 4 days). BOD removal (55.6 %) for the piggery wastewater was achieved in 3 days and 24.9 % - for the landfill leachate after 4 days. The decreasing of organics at aerobic conditions was accompanied with the ammonium ions decreasing - 1.5 times for the piggery wastewater and 4 times for the leachate. In the second stage - biofilter without aeration, an additional organic loading decreasing was achieved. The COD decreased from 820.9 mg/dm3 to 274.3 mg/dm3 for piggery wastewater and for the leachate - from 869.5 mg/dm3 to 423.6 mg/dm3. The BOD values decreased from 384.1 mg/dm3 to 106.8 mg/dm3 for the piggery wastewater and for leachate - from 117.8 mg/dm3 to 57.4 mg/dm3. The ammonium ions were eliminated from both types of wastewaters. In the third stage (subsurface vertical flow wetland) the emission standards for discharge into the sewage collection systems or into the water bodies are met.
The present research assessed the treatment effi ciency of odorogenous pollutants in air from a hatchery hall vented on organic and organic-mineral beds of an enclosed-container biofi lter. In this study, the following media were used: organic medium containing compost and peat (OM); organic-mineral medium containing bentonite, compost and peat (BM); organic-mineral medium containing halloysite, compost and peat (HM). The concentration of odorogenous gaseous pollutants (sulfur compounds and amines) in the hatching room air and in the air after biotreatment were determined by gas chromatography. In the hatchery hall among the typical odorogenous pollutants, there were determined 2 amines: 2-butanamine and 2-pentanamine, hydrogen sulfi de, sulfur dioxide, carbon disulfi de, sulfi des and mercaptans. Ethyl mercaptan showed the highest levels as its mean concentration in the hatchery hall air exceeded 60 μg/m3 and in single samples even 800 μg/m3. A mean concentration of 2-butanamine and sulfur dioxide in the examined air also appeared to be relatively high – 21.405 μg/m3 and 15.279 μg/m3, respectively. In each fi lter material, the air treatment process ran in a different mode. As the comparison reveals, the mean reduction of odorogenous contaminants recorded in the hall and subjected to biotreatment was satisfying as it surpassed 60% for most established pollutants. These high removal values were confi rmed statistically only for single compounds. However, a low removal level was reported for hydrogen sulfi de and sulfur dioxide. No reduction was recorded in the bentonite supplemented medium (BM) for sulfur dioxide and methyl mercaptan. In the organic medium (OM) no concentration fall was noted for dipropyl sulfi de either. In all the media investigated, the highest removal rate (100%), not confi rmed statistically, was observed for carbon disulfi de. Very good results were obtained in the medium with a bentonite additive (BM) for both identifi ed amines, whose mean elimination rate exceeded 60% (p≤0.05). The present research proved that diethyl sulfi de is most susceptible to biofi ltration (over 80%) in the bed supplemented with halloysite (HM) and bentonite (BM) (p≤0.05).
The studies conducted in the three-stage waste-water treatment plant for agricultural and domestic sewage in Łężany showed that the greatest reduction of indicator microorganisms, between 70% and 100%, occured in biological ponds. Biofilters (rotating biological disks and multicage rotating contactor) reduced the occurence of the studied microorganisms by 40—70%, mechanical purification by 40—50%. The purified sewage flowing to Legińskie Lake possessed the features of unpolluted or only slightly polluted water.
The aim of this study was to develop a biofiltration system able to remove TCE from contaminated air and to optimize its operating conditions. Three types of one- and two-step installations were examined for the capacity to remove gas-phase trichloroethene from waste air. The immobilizate of the biomass active in TCE decomposition was used in the process. The efficiency of the process and metabolic activity of biomass were investigated. The stable and effective biofiltration process was achieved when a two-step installation was used with hybrid bioreactor containing activated sludge suspension with active biomass immobilizate (bioscrubber) being the first step. The second step was a biofilter filled with traditional deciduous leaf debris compost mixed with wood chips and activated carbon. The efficiency of contaminant elimination achieved during 2.5 months of operation was between 52% and 92%. The bioscrubber activity in gas purification was high - even up to 76%, and biofilter capacity for contaminant elimination was in the range 65-88.3 g TCE/m³/h. Active strains of microorganisms selected in the course of the process were isolated and identified. Dominant bacteria belonged to the genus Streptomyces, Sarcina, Arthrobacter, Bacillus and also to Gramnegative rods from species Agrobacterium radiobacter and Sphingomonas paucimobilis. Moreover, two dominant strains of moulds and one strain of yeast were isolated from the biofilter-bed.
A novel biofi lter containing organic, bentonite and halloysite media was applied for elimination of microbial pollutants from the air of an industrial hatchery. The concentrations of total mesophilic bacteria, Gram-negative bacteria, thermophilic actinomycetes, dust and bacterial endotoxin were determined in the air of hatchery during 2 months before installation of the biofi lter, and during 6 months after installation of the biofi lter, at the inlet and outlet ducts from each medium. Before installation of the biofi lter, the concentrations of total mesophilic bacteria, Gram-negative bacteria, thermophilic actinomycetes, dust and endotoxin in the air were within the ranges of 0.97- 131.2 × 103 cfu/m3, 0.0-34.4 × 103 cfu/m3, 0.0-0.02 × 103 cfu/m3, 0.37-4.53 mg/m3, and 50.9-520,450.4 ng/m3, respectively. Enterococcus faecalis and Gram-negative bacteria (Acinetobacter spp., Escherichia coli, Enterobacter cloacae, and other species) prevailed among bacterial species recovered from the air of the hatchery. A total of 56 species or genera of bacteria were identifi ed in the air samples taken in the examined hatchery; of these, 11, 11 and 6 species or genera respectively were reported as having allergenic, immunotoxic and/or infectious properties The concentrations of total mesophilic bacteria, Gram-negative bacteria, Enterococcus faecalis and endotoxin found at the inlet duct of the biofi lter after its installation were signifi cantly smaller compared to those recorded before its installation (p<0.05). The concentrations of Gram-negative bacteria, Enterococcus faecalis and dust found at the outlet ducts of biofi lter after its installation were signifi cantly smaller compared to those recorded at the inlet duct of the biofi lter (p<0.01). The concentrations of total meso-philic bacteria were also smaller at the outlet ducts of the biofi lter compared to that at the inlet duct; however, the difference was not signifi cant because of the massive growth of Streptomyces species in the biofi lter’s media which contaminated the outcoming air. In conclusion, the applied biofi lter proved to be effective in the elimination of potentially pathogenic bacteria, dust and endotoxin from the air of the hatchery. The effi cacy of the biofi lter could be improved by the inhibition of the Streptomyces growth in the media of the biofi lter.
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