842 resultados para sludge reduction
Resumo:
Experiments were carried out in a growth chamber with controlled temperature and photoperiod to test two populations of Blumeria graminis f. sp. hordei from Guarapuava, Paraná State, and Passo Fundo, Rio Grande do Sul State, Brazil. Treatments consisted in application of the fungicide triadimenol (Baytan 150 SC®) at three rates of its commercial formulation: 150, 250, 350 mL/100 Kg barley seeds. The experiments were conducted separately in a growth chamber for each population, adopting the same temperature and photoperiod. For inoculation, pots containing barley seedlings colonized by the fungus were placed among the plots. After emergence of the first symptoms, the disease severity was assessed at two-day intervals. The experiments were repeated twice for each fungus population. Data were expressed as area under the disease progress curve and as powdery mildew control by comparing the severity after the fungicide treatments to that of control. Data were subjected to analysis of variance and regression analysis; the area under the disease progress curve was also calculated. Comparing the data obtained in the present study with those reported in the literature and the control, the maximum value of 26.1% is considered insufficient to prevent the damages caused by the disease. The control response to the fungicide rate was significant. We can conclude that there was a reduction in the sensitivity of both B. graminis f.sp. hordei populations to the fungicide triadimenol, which explains the control failure observed in barley farms.
Resumo:
In Brazil, Fusarium head blight (FHB) affecting wheat can cause up to 39.8% damage. Resistant cultivars are not available yet; thus, short-term disease control relies on the use of fungicides. The first step to improve control is to monitor fungal populations that are sensitivity to chemicals in order to achieve efficient FHB management. In vitro experiments were conducted to evaluate the inhibitory concentration (IC50) of fungicides for both mycelial growth and conidial germination of ten Fusarium graminearum isolates. The following demethylation inhibitor (DMI) fungicides were tested: metconazole, prothioconazole and tebuconazole. In addition, pyraclostrobin and trifloxystrobin were included, representing QoI fungicides, as well as three co-formulations containing metconazole + pyraclostrobin, prothioconazole + trifloxystrobin, and tebuconazole + trifloxystrobin. For mycelial growth, the overall mean IC50 of isolates was: metconazole 0.07, prothioconazole 0.1, and tebuconazole 0.19 mg/L. For the co-formulations, it was: prothioconazole + trifloxystrobin 0.08, tebuconazole + trifloxystrobin 0.12, and metconazole + pyraclostrobin 0.14 mg/L. Regarding spore germination inhibition, IC50 for prothioconazole + trifloxystrobin was 0.06, for tebuconazole + trifloxystrobin, 0.12 mg/L, for QoI alone pyraclostrobin, was 0.09, and for trifloxystrobin, 0.28 mg/L. There was a sensitivity shift among isolates and the highest fungitoxicity to F. graminearum was confirmed for prothioconazole, metconazole and tebuconazole .
Resumo:
Original sludge from wastewater treatment plants (WWTPs) usually has a poor dewaterability. Conventionally, mechanical dewatering methods are used to increase the dry solids (DS) content of the sludge. However, sludge dewatering is an important economic factor in the operation of WWTPs, high water content in the final sludge cake is commonly related to an increase in transport and disposal costs. Electro‐dewatering could be a potential technique to reduce the water content of the final sludge cake, but the parameters affecting the performance of electro‐dewatering and the quality of the resulting sludge cake, as well as removed water, are not sufficiently well known. In this research, non‐pressure and pressure‐driven experiments were set up to investigate the effect of various parameters and experimental strategies on electro‐dewatering. Migration behaviour of organic compounds and metals was also studied. Application of electrical field significantly improved the dewatering performance in comparison to experiments without electric field. Electro‐dewatering increased the DS content of the sludge from 15% to 40 % in non‐pressure applications and from 8% to 41% in pressure‐driven applications. DS contents were significantly higher than typically obtained with mechanical dewatering techniques in wastewater treatment plant. The better performance of the pressure‐driven dewatering was associated to a higher current density at the beginning and higher electric field strength later on in the experiments. The applied voltage was one of the major parameters affecting dewatering time, water removal rate and DS content of the sludge cake. By decreasing the sludge loading rate, higher electrical field strength was established between the electrodes, which has a positive effect on an increase in DS content of the final sludge cake. However interrupted voltage application had anegative impact on dewatering in this study, probably because the off‐times were too long. Other factors affecting dewatering performance were associated to the original sludge characteristics and sludge conditioning. Anaerobic digestion of the sludge with high pH buffering capacity, polymer addition and freeze/thaw conditioning had a positive impact on dewatering. The impact of pH on electro‐dewatering was related to the surface charge of the particles measured as zeta‐potential. One of the differences between electro‐dewatering and mechanical dewatering technologies is that electro‐dewatering actively removes ionic compounds from the sludge. In this study, dissolution and migration of organic compounds (such as shortchain fatty acids), macro metals (Na, K, Ca, Mg, Fe) and trace metals (Ni, Mn, Zn, Cr) was investigated. The migration of the metals depended on the fractionation and electrical field strength. These compounds may have both negative and positive impacts on the reuse and recycling of the sludge and removed water. Based on the experimental results of this study, electro‐dewatering process can be optimized in terms of dewatering time, desired DS content, power consumption and chemical usage.
Resumo:
Delays in the justice system have been undermining the functioning and performance of the court system all over the world for decades. Despite the widespread concern about delays, the solutions have not kept up with the growth of the problem. The delay problem existing in the justice courts processes is a good example of the growing need and pressure in professional public organizations to start improving their business process performance.This study analyses the possibilities and challenges of process improvement in professional public organizations. The study is based on experiences gained in two longitudinal action research improvement projects conducted in two separate Finnish law instances; in the Helsinki Court of Appeal and in the Insurance Court. The thesis has two objectives. First objective is to study what kinds of factors in court system operations cause delays and unmanageable backlogs and how to reduce and prevent delays. Based on the lessons learned from the case projects the objective is to give new insights on the critical factors of process improvement conducted in professional public organizations. Four main areas and factors behind the delay problem is identified: 1) goal setting and performance measurement practices, 2) the process control system, 3) production and capacity planning procedures, and 4) process roles and responsibilities. The appropriate improvement solutions include tools to enhance project planning and scheduling and monitoring the agreed time-frames for different phases of the handling process and pending inventory. The study introduces the identified critical factors in different phases of process improvement work carried out in professional public organizations, the ways the critical factors can be incorporated to the different stages of the projects, and discusses the role of external facilitator in assisting process improvement work and in enhancing ownership towards the solutions and improvement. The study highlights the need to concentrate on the critical factors aiming to get the employees to challenge their existing ways of conducting work, analyze their own processes, and create procedures for diffusing the process improvement culture instead of merely concentrating of finding tools, techniques, and solutions appropriate for applications from the manufacturing sector
Resumo:
Kuumahiertoprosessi on erittäin energiaintensiivinen prosessi, jonka energianominaiskulutus (EOK) on yleisesti 2–3.5 MWh/bdt. Noin 93 % energiasta kuluu jauhatuksessa jakautuen niin, että kaksi kolmasosaa kuluu päälinjan ja yksi kolmasosa rejektijauhatuksessa. Siksi myös tämän työn tavoite asetettiin vähentämään energian kulutusta juuri pää- ja rejektijauhatuksessa. Päälinjan jauhatuksessa tutkimuskohteiksi valittiin terityksen, tehojaon ja tuotantotason vaikutus EOK:een. Rejektijauhatuksen tehostamiseen pyrittiin yrittämällä vähentää rejektivirtaamaa painelajittelun keinoin. Koska TMP3 laitoksen jauhatuskapasiteettia on nostettu 25 %, tavoite oli nostaa päälinjan lajittelun kapasiteettia saman verran. Toisena tavoitteena oli pienentää rejektisuhdetta pää- ja rejektilajittelussa ja siten vähentää energiankulutusta rejektijauhatuksessa. Näitä tavoitteita lähestyttiin vaihtamalla päälinjan lajittimiin TamScreen-roottorit ja rejektilajittimiin Metso ProFoil-roottorit ja optimoimalla kuitufraktiot sihtirumpu- ja prosessiparametrimuutoksin. Syöttävällä terätyypillä pystyttiin vähentämään EOK:ta 100 kWh/bdt, mutta korkeampi jauhatusintensiteetti johti myös alempiin lujuusominaisuuksiin, korkeampaan ilmanläpäisyyn ja korkeampaan opasiteettiin. Myös tehojaolla voitiin vaikuttaa EOK:een. Kun ensimmäisen vaiheen jauhinta kuormitettiin enemmän, saavutettiin korkeimmillaan 70 kWh/bdt EOK-vähennys. Tuotantotason mittaamisongelmat heikensivät tuotantotasokoeajojen tuloksia siinä määrin, että näiden tulosten perusteella ei voida päätellä, onko EOK tuotantotasoriippuvainen vai ei. Päälinjan lajittelun kapasiteettia pystyttiin nostamaan TS-roottorilla vain 18 % jääden hieman tavoitetasosta. Rejektilajittelussa pystyttiin vähentämään rejektimäärää huomattavasti Metso ProFoil-roottorilla sekä sihtirumpu- ja prosessiparametrimuutoksin. Lajittamokehityksellä saavutettu EOK-vähennys arvioitiin massarejektisuhteen pienentymisen ja rejektijauhatuksessa käytetyn EOK:n avulla olevan noin 130 kWh/bdt. Yhteenvetona voidaan todeta, että tavoite 300 kWh/bdt EOK-vähennyksestä voidaan saavuttaa työssä käytetyillä tavoilla, mikäli niiden täysi potentiaali hyödynnetään tuotannossa.
Resumo:
The deficient environmental preservation on agricultural properties has reflected in great soil losses for erosion and the high rate of sedimentation. Therefore, this work brings the application of software to demonstrate that planters can get benefits by the conservationist practices. The benefits will be obtained from the environment aspect (erosion and sedimentation control), as well as economical aspect (financial incentives). A proposal has been created by the Technical Chamber of Rural Water Use and Conservation (CT-Rural) to estimate the reduction in raw water use charge for the rural water users of the PCJ Watershed - this reduction is being possible since January 2007, at the PCJ Committee. The software develops a simple relationship, so that if the rural conservationist action goes more efficient, such as if the conserved rural area goes larger, then the reduction value will bring better benefits for the rural water users. Within the purposes of this study, there is the idealization of mechanisms that may support specific management matters related to the water users of federal rivers from the rural sector of PCJ Watershed.
Resumo:
The high load of nitrogen present in swine wastewater is one of the biggest management challenges of the activity. The Anammox process emerges as a good alternative for biological removal of nitrogen. This study aims to acclimate sludge collected from swine effluent treatment systems to establish the Anammox process. Two sludge samples were collected at Embrapa Swine and Poultry, Concordia - SC, Brazil, one from the bottom of an inactive anaerobic pond (inoculum A) and another from an aeration tank (inoculum B). Both were acclimated until the depletion of NO3-N, being subsequently inoculated in two reactors (Reactor A - Inoculum A and Reactor B - Inoculum B). The Reactor A showed activity after 110 days of operation, while the Reactor B needed 170 days. The difference in the start-up time could be explained by the different environmental conditions to which each sludge was submitted. FISH and PCR analyses confirmed the presence of microorganisms with Anammox activity, demonstrating that the sludge of swine wastewater treatment systems is a good source of inoculum for the development of the Anammox process.
Resumo:
With the intense debate, in Brazil, between landowners and public agencies about the amount of area with forest cover needed in different regions, there is an increase of the need for provision of technical data used as a basis for decision making. One of the criteria to evaluate the effect of forest cover in protecting water resources is the soil loss, which leads to several consequences on the environment, including the silting of the rivers. Therefore, this study aimed to evaluate the reduction in the soil loss in micro watersheds with different reliefs, size and location of forest cover, in the Corumbataí River watershed, in the state of São Paulo, using the Revised Universal Soil Loss Equation (RUSLE) in a GIS environment. For this study, 18 watersheds in three degrees of slope were selected, and 20 scenarios for land-use were established, by analyzing the influence of the PPA size, and the size and the location of the Legal Reserve. The results showed that: a) the effect of forest cover in reducing annual soil loss varies depending on the average slope of the watershed; b) the PPA width must be determined taking into account the slope of the watershed; c) the Legal Reserve must be located along the PPA. These provide better results in reducing annual soil loss.
Resumo:
In this study it was evaluated the start-up procedures of anaerobic treatment system with three horizontal anaerobic reactors (R1, R2 and R3), installed in series, with volume of 1.2 L each. R1 had sludge blanket, and R2 and R3 had half supporter of bamboo and coconut fiber, respectively. As an affluent, it was synthesized wastewater from mechanical pulping of the coffee fruit by wet method, with a mean value of total chemical oxygen demand (CODtotal) of 16,003 mg L-1. The hydraulic retention time (HRT) in each reactor was 30 h. The volumetric organic loading (VOL) applied in R1 varied from 8.9 to 25.0 g of CODtotal (L d)-1. The mean removal efficiencies of CODtotal varied from 43 to 97% in the treatment system (R1+R2+R3), stabilizing above 80% after 30 days of operation. The mean content of methane in the biogas were of 70 to 76%, the mean volumetric production was 1.7 L CH4 (L reactor d)-1 in the system, and the higher conversions were around at 0.20 L CH4 (g CODremoved)-1 in R1 and R2. The mean values of pH in the effluents ranged from 6.8 to 8.3 and the mean values of total volatile acids remained below 200 mg L-1 in the effluent of R3. The concentrations of total phenols of the affluent ranged from 45 to 278 mg L-1, and the mean removal efficiency was of 52%. The start-up of the anaerobic treatment system occurred after 30 days of operation as a result of inoculation with anaerobic sludge with active microbiota.
Resumo:
In this study it was evaluated the efficiency of the treatment of wet-processed coffee wastewater in upflow anaerobic sludge blanket (UASB) reactors in two stages, in bench scale, followed by post-treatment with activated sludge in batch. The first UASB reactor was submitted to an hydraulic retention time (HRT) of 6.2 d and organic loading rates (OLR) of 2.3 and 4.5g CODtotal (L d)-1, and the second UASB reactor to HRT of 3.1 d with OLR of 0.4 and 1.4g CODtotal (L d)-1. The average values of the affluent CODtotal increased from 13,891 to 27,926mg L-1 and the average efficiencies of removal of the CODtotal decreased from 95 to 91%, respectively, in the UASB reactors in two stages. The volumetric methane production increased from 0.274 to 0.323L CH4 (L reactor d)-1 with increment in the OLR. The average concentrations of total phenols in the affluent were of 48 and 163mg L-1, and the removal efficiencies in the UASB reactors in two stages of 92 and 90%, respectively, and increased to 97% with post-treatment. The average values of the removal efficiencies of total nitrogen and phosphorus were of 57 to 80% and 44 to 60%, respectively, in the UASB reactors in two stages and increased to 91 and 84% with the post-treatment.
Resumo:
ABSTRACT Water and sewage treatment plants (STP and WTP) generate as byproduct a significant amount of sludge with environment harmful elements. Sending to landfills or depositing on the ground or rivers are respectively expensive and dangerous alternatives. In this scenario, the use of this waste in paving processes is a promising alternative for disposal thereof. In this study, we focused on characterizing sludge and evaluating its use in paving, which showed satisfactory results for use in base and sub-base floors.
Resumo:
Biogas production has considerable development possibilities not only in Finland but all over the world since it is the easiest way of creating value out of various waste fractions and represents an alternative source of renewable energy. Development of efficient biogas upgrading technology has become an important issue since it improves the quality of biogas and for example facilitating its injection into the natural gas pipelines. Moreover, such upgrading contributes to resolving the issue of increasing CO2 emissions and addresses the increasing climate change concerns. Together with traditional CO2 capturing technologies a new class of recently emerged sorbents such as ionic liquids is claimed as promising media for gas separations. In this thesis, an extensive comparison of the performance of different solvents in terms of CO2 capture has been performed. The focus of the present study was on aqueous amine solutions and their mixtures, traditional ionic liquids, ‘switchable’ ionic liquids and poly(ionic liquid)s in order to reveal the best option for biogas upgrading. The CO2 capturing efficiency for the most promising solvents achieved values around 50 - 60 L CO2 / L absorbent. These values are superior to currently widely applied water wash biogas upgrading system. Regeneration of the solvent mixtures appeared to be challenging since the loss of initial efficiency upon CO2 release was in excess of 20 - 40 vol %, especially in the case of aqueous amine solutions. In contrast, some of the ionic liquids displayed reversible behavior. Thus, for selected “switchable” ionic and poly(ionic liquid)s the CO2 absorption/regeneration cycles were performed 3 - 4 times without any notable efficiency decrease. The viscosity issue, typical for ionic liquids upon CO2 saturation, was addressed and the information obtained was evaluated and related to the ionic interactions. The occurrence of volatile organic compounds (VOCs) before and after biogas upgrading was studied for biogas produced through anaerobic digestion of waste waters sludge. The ionic liquid [C4mim][OAc] demonstrated its feasibility as a promising scrubbing media and exhibited high efficiency in terms of the removal of VOCs. Upon application of this ionic liquid, the amount of identified VOCs was diminished by around 65 wt %, while the samples treated with the aqueous mixture of 15 wt % N-methyldiethanolamine with addition of 5 wt % piperazine resulted in 32 wt % reduction in the amounts of volatile organic compounds only.
Resumo:
In Finland the thermal treatment of sewage sludge has been moderate in 21th century. The reason has been the high moisture content of sludge. During 2005-2008, 97-99% of sewage sludge was utilized in landscaping and agriculture. However agricultural use has been during 2005-2007 less than 3 %. The aim of national waste management plan is that by 2016 100% of sludge is used either as soil amendment or energy. The most popular utilization method for manure is spreading it on arable land. The dry manures such as poultry manure and horse manure could also be used in incineration. The ashes could be used as fertilizers and while it is not suitable as a starter fertilizer, it is suitable in maintaining P levels in the soil. One of the main drivers for more efficient nutrient management is the eutrophication in lakes and the Baltic See. ASH DEC process can be used in concentrating phosphorus rich ashes while separating the heavy metals that could be included. ASH DEC process uses thermochemical treatment to produce renewable phosphate for fertilizer production. The process includes mixing of ashes and chlorine donors and subsequent treatment in rotary kiln for 20 min in temperature of 900 – 1 050 oC. The heavy metals evaporate and P-rich product is obtained. The toxic substances are retained in air pollution control system in form of mixed metal hydroxides. The aim of conducting this study is to estimate the potential of ASH DEC process in treating phosphorus rich ashes in Finland. The masses considered in are sewage sludge, dry manure from horses, and poultry and liquid pig manure. To date the usual treatment method for sewage sludge in Finland is composting or anaerobic digestion. Part of the amount of produced sewage sludge (800 kt/a fresh mass and 160 kt/a TS) could also be incinerated and the residual ashes used in ASH DEC process. Incinerating only manure can be economically difficult to manage because the incineration of manure is in Finland considered as waste incineration. Getting a permit for waste incineration is difficult and also small scale waste incineration is too expensive. The manure could act as an additional feedstock in counties with high density of animal husbandry where the land area might not be enough for spreading of manure. Now when the manure acts as a supplementary feedstock beside sludge, the ash can’t be used directly as fertilizer. Then it could be used in ASH DEC process. The perquisite is that the manure producers could pay for the incineration, which might prove problematic.