Oceanography of Saanich Inlet in Vancouver Island, British Columbia

1962 ◽  
Vol 19 (1) ◽  
pp. 1-37 ◽  
Author(s):  
R. H. Herlinveaux

Saanich Inlet is a fjord (24 km long) having a submerged (75-m) sill at the entrance, behind which there is a deep (234-m) basin. The properties of the water have been observed from time to time from 1927 through 1960. The resulting data are reviewed to provide representative values and structures of temperature, salinity, density (σt), dissolved oxygen content and sound velocity for each month throughout the year. Above the sill depth the properties of the water are normal and continuous with those in the approaches which connect with the Strait of Georgia. The waters below the sill depth are isolated, oxygen-deficient, and usually contain hydrogen sulphide. There is considerable ambient variation in the structures because the currents are too weak to disperse or mix the locally generated concentrations.The runoff into the head of the inlet is negligible. The major source of fresh water is in the approaches. It intrudes the inlet and provides a weak estuarine flushing mechanism above the sill depth. The waters below the sill are flushed only when the water in the approaches becomes sufficiently dense to cascade over the sill into the deep basin.The sound-ranging conditions are far from ideal. From March through July there is a major sound channel at mid-depths above the sill. This vanishes in August and a sound divergence zone develops and persists until December. In addition, the ambient variations provide anomalous transmission conditions.During the autumn (September through November) high concentrations of fish have been observed at the sill depth, associated with the oxycline. Probably the fish are attracted to the area by very large concentrations of zooplankton (Euphausids) that have been observed there at the same time.

1975 ◽  
Vol 32 (11) ◽  
pp. 2075-2089 ◽  
Author(s):  
C. A. Lafond ◽  
G. L. Pickard

Bute Inlet is a fjord of the British Columbia mainland coast connected to the Strait of Georgia through Sutil Channel. The properties of the waters in the inlet were observed during a series of cruises from June 1972 to June 1974 with the main objective of determining the water exchange below the top 100 m.Vertical longitudinal sections and time-series plots of salinity, temperature, and dissolved oxygen distributions measured during the 2-yr survey were used to analyze the circulation patterns and renewal processes of the water below 100 m.Inflows of deep water from the Strait of Georgia into Bute occurred frequently during the study period, and took place when the water from the Strait of Georgia above the inlet sill depth was denser than the water in the basin of the inlet. Volumes of some inflows into Bute were estimated, and calculations indicate that inflow speeds could be large enough to be recorded by existing current meters. The renewal of the deep water in Bute Inlet basin appears to be basically consistent with the annual cycle of deepwater replacement in the Strait of Georgia with its year-to-year variations.


2018 ◽  
Vol 27 (1) ◽  
pp. 85
Author(s):  
José A. Acaro R ◽  
Jeannie L. Quispe E. ◽  
Mali I. Salas D.

Nuestro equipo en esta oportunidad hizo una simulación de una torre de lavado, la cual la aplicamos en el reactor UASB, a manera de escala construimos una torre de lavado compuesta por difusores, una cama de sólidos hecha de material de esponja, un tubo de acrílico y todas las conexiones que conducen el biogás con H2S. Los componentes a eliminar y/o remover fueron los gases que salen del reactor, en especial del H2S (gas odorífero y toxico que a grandes concentraciones pude llevar a la muerte y como resultado de sus reacciones con el ambiente puede causar daños en las estructuras con la cual este en contacto) mediante la oxidación con el oxígeno disuelto que proveen las microalgas presentes en el agua de la laguna terciara utilizada. Esta torre de lavado la montamos en las instalaciones de CITRAR‐UNI con el permiso del operador y vimos el comportamiento que tiene esta torre, mediante los monitoreos de oxígeno disuelto, temperatura, pH y sulfatos que realizamos durante tres semanas de monitoreo. Como resultados obtuvimos que la torre de lavado sí oxidaba y removía la contracción de H2S, ya que cuando pasaba el tiempo se consumía el oxígeno disuelto, además de esto también en el monitoreo de sulfatos pudimos observar un aumento de este parámetro es decir la torre si estaba consumiendo en H2S, y por esta razón también disminuyo el olor fétido que produce este gas. Palabras clave.- Torre de lavado, reactor UASB, remoción de sulfuro de hidrógeno. ABSTRACT The present work reports the simulation of a wet scrubber coupled to an UASB reactor. The scrubber consisted of baffles, packed bed of sponge material, an acrylic tube and all the connections necessary to bring the H2S‐ladden biogas. The purpose of the equipment is to eliminate some of the gases coming out of the reactor, through their oxidation by the dissolved oxygen provided by the microalgae present in the water from the tertiary lagoon. Hydrogen sulfide is a foul‐ smelling and toxic gas which can cause death at high concentrations, and can also cause damage to the structures with which it comes into contact. The scrubber was installed on the site of CITRAR‐UNI and the behavior of the equipment was monitored during three weeks by following the temperature, pH and the concentrations of sulfates and dissolved oxygen. The results have shown that the scrubber was effectively an oxidizing environment which was removing H2S, since the dissolved oxygen was actually consumed gradually. It was also observed that the sulfate concentration was increasing, indicating a consumption of H2S, which was also confirmed by a reduction in the odor of the gas. Keywords.- scrubber, UASB reactor, hydrogen sulfide removal .


2011 ◽  
Vol 356-360 ◽  
pp. 959-962
Author(s):  
Ji Ping Ma ◽  
Cui Jie Rui ◽  
Jian Hua Ge ◽  
Yu Hua Liu ◽  
Zhi Wen Song ◽  
...  

Based on the Jihogntan reservoir’s monitoring data from 2006 to 2009, eutrophication of Jihongtan reservoir was assessed. The result showed that the nutrition level of the Jihongtan reservoir was middle in recent years. The average concentration of chlorophyll-a(Chla) was higher in summer and autumn than in spring and winter. The correlation between concentration of Chla and some environmental factors was studied by statistical method, and seasonal variation of Chla and the extent of eutrophication were also analyzed. The results showed that the correlations between Chla and total nitrogen(TN), dissolved oxygen(DO) and transparency were significantly negative, and that between Chla and total phosphorus(TP), temperature(T) and potassium permanganate index(COD Mn) were significantly positive. The growth of phytoplankton was promoted by TP and TN at low concentrations, and inhibited by TN at high concentrations.


1980 ◽  
Vol 88 (1) ◽  
pp. 239-248
Author(s):  
A. G. LOGAN ◽  
R. MORRIS ◽  
J. C. RANKIN

Micropuncture techniques have been used to investigate kidney function in lampreys adapted to hyperosmotic media. Plasma electrolyte concentrations were maintained well below corresponding concentrations in the external environment. Urine composition was variable, but generally showed high concentrations of magnesium, sulphate and chloride ions. Lampreys in 50% sea water produced urine which was hypo or iso-osmotic to plasma, whereas those in 100% sea water produced hyperosmotic urine. Urine flow rate in 50% sea water was one tenth of that in fresh water, due to a reduction in filtration rate and an increase in water reabsorption by the kidney. As in fresh water, little if any filtered water was reabsorbed by the proximal segment. Almost 90% of filtered water was reabsorbed by the kidney of 100% sea water lampreys and most of this must have occurred in the distal and collecting segments.


2001 ◽  
Vol 43 (3) ◽  
pp. 283-290 ◽  
Author(s):  
G. Buitrón ◽  
G. Soto ◽  
G. Vite ◽  
J. Moreno

This study presents two strategies used to enhance the biological degradation of phenolic wastewaters. In the first one the operation of a sequencing batch biofilter added with granular activated carbon (SBB-AC) was studied. The second strategy presents the results of the automation of a sequencing batch reactor in order to optimize the reaction phase. In this case, the dissolved oxygen was employed to monitor and control the reactor. The results of the SBB-AC system, based on the configuration of the reactor, type and size of activated carbon and size of the packing material, are discussed. The system biodegraded efficiently (total phenol removals as high as 97%) high concentrations (600 mg/l) of a mixture of phenol, 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol. Maximal eliminated loads of 4.33 kg COD/m3-d were achieved. For the second strategy, the applicability of an optimal control for a SBR using the dissolved oxygen as the measured variable was demonstrated. When the reactor was operated under the time-optimal control strategy, the degradation time of 4-chlorophenol was reduced. A very satisfactory operation of the reactor was observed, since the removal efficiencies were around 99%.


1999 ◽  
Vol 40 (1) ◽  
pp. 245-252 ◽  
Author(s):  
H. Schenk ◽  
M. Wiemann ◽  
W. Hegemann

Sulphide, and especially the undissociated form, hydrogen sulphide, is inhibitory to anaerobic wastewater treatment processes. Tannery beamhouse wastewater contains high concentrations of organic material which make an anaerobic treatment favourable, but it also contains high concentrations of sulphide which cause difficulties for anaerobic treatment. The success of an anaerobic treatment will depend on reliable elimination of the sulphide. In batch tests stripping was the most effective process for sulphide removal compared to precipitation. The chemical-physical COD removal caused by the stripping was negligible, while precipitation caused a COD-removal of 26%. Also, anaerobic degradation velocity was higher if sulphide was removed by stripping. In fixed bed reactors operated continuously, stripping was shown to be a reliable method for eliminating hydrogen sulphide toxicity. Hydrogen sulphide caused an inhibition of 0.2% per mg 1−1 for methanogenic bacteria. Acidogenic bacteria were not inhibited by hydrogen sulphide. The gas-liquid equilibrium was shown to deviate from theoretical values taken from literature.


2019 ◽  
Vol 20 (10) ◽  
pp. 2550 ◽  
Author(s):  
Alida Spalloni ◽  
Viviana Greco ◽  
Giulia Ciriminna ◽  
Victor Corasolla Carregari ◽  
Federica Marini ◽  
...  

A number of factors can trigger amyotrophic lateral sclerosis (ALS), although its precise pathogenesis is still uncertain. In a previous study done by us, poisonous liquoral levels of hydrogen sulphide (H2S) in sporadic ALS patients were reported. In the same study very high concentrations of H2S in the cerebral tissues of the familial ALS (fALS) model of the SOD1G93A mouse, were measured. The objective of this study was to test whether decreasing the levels of H2S in the fALS mouse could be beneficial. Amino-oxyacetic acid (AOA)—a systemic dual inhibitor of cystathionine-β-synthase and cystathionine-γ lyase (two key enzymes in the production of H2S)—was administered to fALS mice. AOA treatment decreased the content of H2S in the cerebral tissues, and the lifespan of female mice increased by approximately ten days, while disease progression in male mice was not affected. The histological evaluation of the spinal cord of the females revealed a significant increase in GFAP positivity and a significant decrease in IBA1 positivity. In conclusion, the results of the study indicate that, in the animal model, the inhibition of H2S production is more effective in females. The findings reinforce the need to adequately consider sex as a relevant factor in ALS.


2018 ◽  
Vol 84 (4) ◽  
pp. 605-612 ◽  
Author(s):  
Toshinao Ineno ◽  
Ryusuke Kodama ◽  
Tomoya Taguchi ◽  
Kazuya Yamada

1984 ◽  
Vol 16 (5-7) ◽  
pp. 95-125 ◽  
Author(s):  
A Azkona ◽  
S H Jenkins ◽  
H M G Roberts

This paper describes part of a comprehensive multidisciplinary study of the pollution of the estuary of the River Nervion, Bilbao, Spain. The objectives of the study were to determine the sources and loads of pollution from domestic sewage and industrial wastewater; provide information on the extent of pollution; formulate hydrodynamic and predictive models capable of forecasting the effects on the estuary of the anticipated growth of population and industry; determine the amount of polluting matter that would have to be removed in order to reach defined estuary water quality standards; arrive at suitable technical methods able to attain these standards at minimum cost; determine the treatability of wastewater discharges and recommend methods for controlling industrial wastewater. These objectives necessitated a survey of the pollution loads from domestic sources and industry which were discharged to the fresh water and tidal reaches of four major tributaries in addition to the main river Nervion; the results of this part of the survey are described in this paper. The presence of iron in discharges from iron ore mining and metal processing was found to aid flocculation of organic matter and the consequent deposition of sludge in the estuary. This action and the rate of oxygen uptake during the decomposition of such deposits are also described. The domestic sewage of the study area receives treatment in septic tanks before discharging to rivers or the estuary. In spite of free hydrogen sulphide and high concentrations being present in the septic tank effluents, odour nuisance does not occur, because, as is shown in the paper, of the formation of ferrous sulphide. The hydrogen sulphide concentration in the atmosphere at a pumping station was found to be above the safety level. The industrial load of impurity was estimated to be approximately 15% higher than the domestic load, but it is extremly difficult to find a rational basis on which comparisons may be made between domestic sewage and a mixture of industrial effluents containing substances inimical to biological activity. The industrial effluent was contained in a very large volume of water, much of it taken from the estuary for cooling or process water. It is calculated that if the industrial pollutants had been contained only in the fresh water used by industry the COD of the mixture would have been 1317 mg/l; the suspended solids 2143 mg/l; the ammonia nitrogen 191 mg/l; iron 1037 mg/l; other heavy metals 118 mg/l; fluoride as F 14.5 mg/l; cyanide as CN 8.1 mg/l; oil 196 mg/l; phenols 8.1 mg/l; mercury 0.13 mg/l; and the mixture would have had an excess of acidity of 5188 mg/l. An estimate of the load of substances having an oxygen demand indicated that of the total oxygen demand discharged to the system of rivers and estuary approximately 50% entered the estuary from the main tributaries, the remainder being discharged directly to the estuary. An outline is given of the methods that would be used to determine the treatability of industrial effluents which were rendered acceptable for discharge into public sewers.


1983 ◽  
Vol 15 (8-9) ◽  
pp. 117-126 ◽  
Author(s):  
M J T Carrondo ◽  
J M C Silva ◽  
M I I Figueira ◽  
R M B Ganho ◽  
J F S Oliveira

Two anaerobic filters were used to assess the treatability of a high strength acidic molasses fermentation wastewater containing up to 3000 mg/l of sulphate ion. The waste had to be neutralized and buffered prior to treatment and the filters operated at ambient temperature. The inlet COD concentrations were increased from 10,000 to 50,000 mg/l, organic loads ranged from 2 to 12 Kg COD/m3 day at hydraulic retention times of 2.5 and 5 days. COD removals varied from 57 to 79% and removal rates as high as 6.8 Kg COD/m3.day were obtained. Although the gas productions were reasonable, reaching 4.8 m3/m3.day, the methane content was always lower than 40% and high concentrations of hydrogen sulphide were detected in the gas. The filters were operated for seven months without sludge removal.


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