Analysis of heat recovery potential from wastewater: case study Hradec Kralove

Získávání tepla z městských odpadních vod má obrovský potenciál na poli obnovitelné energie. Při ochlazení 1m3 odpadní vody o 1°C je možné získat až 1,16 kWh tepelné energie. Tato studie se zaměřuje na výběr vhodného místa pro instalaci tepelného výměníku a návrh výkonu tepelného výměníku. Prvním krokem je předvýběr úseku stokové sítě, vhodného pro instalaci tepelného výměníku. Při prvotním rozhodování o vhodnosti či nevhodnosti instalace tepelného výměníku může být nápomocný SQUID (nový přístroj testovaný v rámci diplomové práce). Po předvýběru vhodného úseku stoky s největším energetickým potenciálem, by měla následovat měřící kampaň a následná analýza změřených dat o průtoku a teplotě odpadní vody ve vybraném úseku stokové sítě. Po analýze změřených dat je zapotřebí ověřit, zda je ve vybraném místě dostatečný energetický potenciál. Při výpočtu energetického potenciálu je nutné brát v úvahu, že instalace tepelného výměníku nesmí negativně ovlivnit čistící procesy probíhající na čistírně odpadních vod. Odpadní voda nesmí být ochlazena pod úroveň zaručující správné fungování procesu čištění odpadní vody. Pokud by podchlazená odpadní voda snížila účinnost čisticích procesů, negativní ekologické dopady by byly mnohem horší než získané energie. Při výpočtu optimálního výkonu tepelného výměníku byl použit výpočetní software TEMPEST, kterým lze dopočítat, na jakou hodnotu, může být snížena teplota odpadní vody v tepelném výměníku. Na základě této hodnoty je možné optimalizovat výkon tepelného výměníku a počet dní kdy bude v provozu. Součástí diplomové práce bude i návrh potenciálních odběratelů vyprodukovaného tepla.Heat recovery from wastewater has a great potential in the field of renewable energy. The energetic potential in wastewater is very large. 1.16 kWh of heat can be recovered from sewer system if the temperature of 1 m3 of wastewater is reduced by 1 °C. An important factor needs to be taken into account: using energy contained in wastewater could have negative impact on the processes in the wastewater treatment plant as well as on the recipient. It is necessary to be especially careful when designing the optimal heat exchanger performance. This study will interconnect the whole process of choosing the suitable sewer system parts for heat exchangers installations and the calculation of heat exchanger performance. The whole process could be divided into a few steps. First of all it is necessary to predefine the spots in sewer system, where the heat potential is the highest. This step could be done with help of the SQUID. After the wastewater heat recovery site preselection, the measuring campaign and data analyzation should follow. Based on data analysis it is necessary to verify if the heat potential is high enough to install the heat exchanger. It is important to keep in mind that the heat exchanger installation should never negatively affect the processes which are running at the wastewater treatment plant. The treatment processes could be negatively affected by reducing wastewater temperature, under the level which guarantees the right wastewater treatment operating. For optimal heat exchangers performance design the wastewater predicting software (TEMPEST) is applied. Based on the results, it is possible to define optimal heat exchanger performance and the number of days when the heat exchanger will be operating. Suggestion of potential heat generation from heat exchange costumers is a part of this thesis as well

A Structural Reinforcement Layer with Woodchips Used on Forest Roads

Described biotechnical measures focus on the use of woodchips in the formation of a structural reinforcement layer on forest roads in the places with high levels of groundwater. These are often short sections of roads which can thus block off entire forests. In history, these sections were overcome using corduroy roads. Currently, there are tendencies to revive the biotechnical technology and replace logs used for corduroy roads with woodchips. This study investigates the possible reinforcement of a waterlogged section using woodchips in a forest road of multifunctional character, which serves for cycling as well as timber transport. In total, three different types of reinforcement were constructed using woodchips in combination with geotextile and crushed stone. The reinforcement was tested by common operations using a timber extraction tractor with tandem axle trailer. The modulus of deformation was measured on the surface and the deformation characteristics of the layer were determined. Subsequently, the shape of the reinforcement cross-section was surveyed. The results have shown that, even with very low modulus of deformation values, the shape of the reinforcement cross-section does not change statistically in two types of the reinforcement technology. These two types of reinforcement can be successfully used for forest roads that perform the recreational function or for timber transport by tractor. The main advantages are that renewable material is used and no extraction and moving of the ground occur during its production

Dual Inoculation with Mycorrhizal and Saprotrophic Fungi Applicable in Sustainable Cultivation Improves the Yield and Nutritive Value of Onion

The aim of this paper was to test the use of dual microbial inoculation with mycorrhizal and saprotrophic fungi in onion cultivation to enhance yield while maintaining or improving the nutritional quality of onion bulbs. Treatments were two-factorial: (1) arbuscular mycorrhizal fungi (AMF): the mix corresponding to fungal part of commercial product Symbivit (Glomus etunicatum, G. microaggregatum, G. intraradices, G. claroideum, G. mosseae, and G. geosporum) (M1) or the single-fungus inoculum of G. intraradices BEG140 (M2) and (2) bark chips preinoculated with saprotrophic fungi (mix of Gymnopilus sp., Agrocybe praecox, and Marasmius androsaceus) (S). The growth response of onion was the highest for the M1 mix treatment, reaching nearly 100% increase in bulb fresh weight. The effectiveness of dual inoculation was proved by more than 50% increase. We observed a strong correlation (r = 0.83) between the growth response of onion bulbs and AM colonization. All inoculation treatments but the single-fungus one enhanced significantly the total antioxidant capacity of bulb biomass, was the highest values being found for M1, S + M1, and S + M2. We observed some induced enhancement of the contents of mineral elements in bulb tissue (Mg and K contents for the M2 and M2, S, and S + M2 treatments, resp.)

Recycled Asphalt as an Alternative to Natural Aggregates for Forest Road Reinforcement

The objective of the present paper is to confirm or reject the possible use of recycled asphalt to reinforce forest haul roads regarding the technical requirements set by the standards and directives relevant to the construction of forest road surfaces. The hypothesis is based on the presumption that recycled materials, if correctly used, can reach the same construction properties as standard materials, hence their application does not have a negative effect on reinforcement quality. On a selected stretch of the forest road, three test sections were constructed with the use of recycled asphalt, however, each of them with a different technological solution. The first section was reinforced with unbound mixture – Type1 without added water, the second section was constructed using a version of vibrated macadam technology, and recycled asphalt was applied to the third section by the method of basic compacting. In each of the sections, tacheometric cross profile measurement was carried out at monthly intervals to monitor the changes in the cross profile shape, and the number of passages of fully loaded logging trucks was registered; static load tests were performed at pre-defined time intervals to determine the deformation moduli such as deformation characteristics of the road surface structural layers. In all three reinforcement versions, the values of deformation moduli observed during the static load tests were between 68–90% of the values set by relevant standards for these technologies using natural aggregates. However, the tacheometric measurements did not reveal statistically significant changes in the shape of the reinforcement cross-section. Based on the obtained results, applying recycled asphalt to reinforce forest roads seems to be a suitable alternative to natural quarry aggregate used in unbound structural layers. Recycled material needs to meet the regulatory limits for foreign elements and pass ecotoxicity tests, which is evidenced by a certificate on material compliance issued by the test laboratory

Identification of a putatively novel trichomonad species in the intestine of a common quail (Coturnix coturnix)

AbstractA common quail (Coturnix coturnix) from a private keeping died unexpectedly and showed a moderate lymphocytic infiltration of the colonic mucosa associated with numerous protozoa-like objects at the pathological examination. These organisms were further identified using chromogenic in situ hybridization (ISH) and gene sequencing. ISH was performed on paraffin embedded tissue sections and produced a positive signal using a probe specific for the 18S ribosomal RNA (rRNA) gene of the order Trichomonadida, but remained negative with probes specific for the 18S rRNA gene of the common bird parasites Histomonas meleagridis, Tetratrichomonas gallinarum or Trichomonas gallinae. The trichomonads were found on the mucosal surface, inside the crypts and also immigrating into the lamina propria mucosae. DNA was extracted from the paraffin embedded tissue and the entire 18S rRNA gene, ITS-1 region, 5.8S rRNA gene, ITS-2 region and a part of the 28S rRNA gene were sequenced using primer walking. The acquired sequence showed 95% homology with Tritrichomonas foetus, a trichomonad never described in birds. A phylogenetic analysis of a part of the 18S rRNA gene or of the ITS-1, 5.8S and ITS-2 region clearly placed this nucleotide sequence within the family of Tritrichomonadidae. Therefore, the authors propose the detection of a putative new Tritrichomonas sp. in the intestine of a common quail

Patterns of Clinical Management of Atopic Dermatitis in Infants and Toddlers: A Survey of Three Physician Specialties in the United States

ObjectiveTo describe atopic dermatitis (AD) management patterns in children ≤36 months old as reported by pediatricians, dermatologists, and allergists in the US.Study designA nationally-representative survey was administered to pediatricians (n = 101), dermatologists (n = 26), and allergists (n = 26). Main outcomes included referrals to health care professionals, suggested/ordered laboratory tests, management approach (dietary, pharmacologic, or combination of both) by age, AD location, and severity.ResultsSignificant differences were observed in referrals to healthcare professionals (P < .001). Pediatricians more frequently referred to dermatologists than allergists in mild (52.4% vs 32.0%) and moderate/severe (60.6% vs 38.1%) cases. Dermatologists referred to allergists less frequently for mild (9.1%) than moderate/severe (40.7%) AD cases. Pediatricians (59%), allergists (61.5%), and dermatologists (26.9%) reported treating at least some of their patients with AD with dietary management (infant formula change) alone (with or without emollients). Soy-based formulas were often used. For mild AD, the most commonly reported first-line pharmacologic treatments included topical emollients, topical corticosteroids, and barrier repair topical therapy/medical devices. Over 80% of physicians used a dietary and pharmacologic combination approach. Dermatologists were most likely to manage AD symptoms with a pharmacologic-only approach. AD lesion location influenced pharmacologic treatment in >80% of physicians.ConclusionsSignificant and distinct differences in AD treatment approach exist among physicians surveyed. Most pediatricians and allergists use formula change as a management strategy in some patients, whereas dermatologists favor a pharmacologic approach. This diversity may result from inadequate evidence for a standard approach. Consistent methods for managing AD are needed

Hippocampal necrosis and sclerosis in cats: A retrospective study of 35 cases

Hippocampal necrosis and hippocampal sclerosis in cats is a neuropathological entity which is a major concern in feline epilepsy. The aim of our study was to identify associated pathologic brain lesions possibly serving as aetiological triggers in this condition. Therefore, the formalin-fixed and paraffin waxembedded brain tissue of 35 cats diagnosed with hippocampal necrosis or sclerosis was examined retrospectively. In 26 cats inflammatory infiltrates could be found in the hippocampus or adjacent brain regions. Fifteen out of these animals demonstrated mild to moderate infiltrations by lymphocytes and complement deposition in the hippocampus similar to human limbic encephalitis, seven showed unspecific, predominantly non-suppurative inflammation, and two demonstrated suppurative inflammation of the hippocampus or adjacent brain regions. Additionally, one cat was diagnosed with central nervous manifestation of feline infectious peritonitis virus and another one with cerebral Toxoplasma gondii infection. Intracranial neoplasia was present in five cases altogether. Three of them comprised meningioma which was present additionally to lesions resembling limbic encephalitis in two cases, and a dentate gyrus alteration in one case. The other two tumour-associated cases comprised oligodendroglioma. Structural alterations of the dentate gyrus together with hippocampal sclerosis were encountered in three cases in total. Besides the case associated with a meningioma, one case demonstrated lesions resembling limbic encephalitis. A vascular infarct in the temporal lobe was encountered in one cat. In four cases no lesions other than hippocampal necrosis or sclerosis were found. The involvement of feline immunodeficiency virus infections, which may be able to produce hippocampal lesions, was not encountered in the cats examined