Comparison of Wastewater Treatment Technologies in the ED-WAVE Tool to Technologies of Similar Cases in Malawi: Case of Blantyre and Soche WWTW

2010 ◽  
Vol 4 (1) ◽  
pp. 57-64
Author(s):  
Victor Chipofya ◽  
Andrzej Kraslawski ◽  
Yury Avramenko
Keyword(s):  
Wastewater Treatment ◽  
Removal Efficiency ◽  
Biological Treatment ◽  
Dry Season ◽  
Wet Season ◽  
Trickling Filters ◽  
Treatment Technologies ◽  
The Difference ◽  
Study Manager

This paper compares the wastewater treatment technologies at Blantyre and Soche wastewater treatment works (WWTW) in Malawi with technologies of a similar case according to the ED-WAVE tool to determine if existing cases in the tool can be invoked and appropriately modified to arrive at a particular design alternative. The ED-WAVE tool is a shareware PC based package for imparting training on wastewater treatment technologies. The system consists of four modules viz. Reference Library, Process Builder, Case Study Manager, and Treatment Adviser. The paper also compares the reduction in the levels of BOD5, COD, and TSS at the three respective treatment works. The study established that there is a similarity in the sequencing of treatment units of Municipal Case 6 in the ED-WAVE tool and the sequencing of treatment units at Blantyre and Soche WWTW, respectively. All the three plants incorporate screening, grit removal, aerobic biological treatment, and sedimentation. Soche and Blantyre WWTW use hand-raked inclined bar screens and constant velocity grit channels, where longitudinal flow velocity is hydraulically controlled. Rotary mechanically-raked bar screens and mechanically stirred grit chambers are used in the ED-WAVE tool. In addition, Municipal Case 6 uses oxidation ditches for aerobic biological treatment while Blantyre and Soche WWTW use trickling filters. BOD5 removal efficiency at Soche WWTW at 95% and 96% for dry season and wet season, respectively, is comparable to the removal efficiency at Municipal Case 6 (95%). The dry season BOD5 removal efficiency at Blantyre WWTW at 87% is slightly lower than the removal efficiency at Municipal Case 6. TSS removal efficiency at Soche WWTW is at 80% in the wet season and 35% in the dry season. TSS removal efficiency at Blantyre WWTW is only 3% in the wet season, while there is an increase of 11% in the wet season. TSS removal efficiency at Municipal Case 6 is 96%. Inspite of the difference in the BOD5 and TSS removal efficiencies at Municipal Case 6 as compared to Blantyre and Soche WWTW, there is a close match in technologies at Blantyre and Soche WWTW, and Municipal Case 6 in Greece as invoked by the Case Study Manager in the ED- WAVE tool. What is evident from this study is the need to appropriately modify the case arrived at through the Case Study Manager in order to come up with a design appropriate to the local situation in terms of operation and maintenance.

Use of chemical upgrading (CU) in Hungary and Slovakia

1994 ◽  
Vol 30 (5) ◽  
pp. 87-95 ◽  
Author(s):  
Susan E. Murcott ◽  
Donald R. F. Harleman
Keyword(s):  
Wastewater Treatment ◽  
Biological Treatment ◽  
Treatment Plant ◽  
Domestic Sewage ◽  
Metal Salts ◽  
Plant Performance ◽  
Eastern European ◽  
Low Doses ◽  
The Past ◽  
Treatment Technologies

In the past decade, the development of polymers and new chemical technologies has opened the way to using low doses of chemicals in wastewater treatment. “Chemical upgrading” (CU) is defined in this paper as an application of these chemical technologies to upgrade overloaded treatment systems (typically consisting of conventional primary plus biological treatment) in Central and Eastern European (CEE) countries. Although some of the chemical treatment technologies are proven ones in North America, Scandinavia, and Germany, a host of factors, for example, the variations in composition and degree of pollution, the type of technologies in use, the type and mix of industrial and domestic sewage, and the amount of surface water, had meant that the viability of using CU in CEE countries was unknown. This report describes the first jar tests of CU conducted during the summer of 1993. The experiments show CU's ability to improve wastewater treatment plant performance and to potentially assist in the significant problem of overloaded treatment plants. Increased removal of BOD, TSS, and P in the primary stage of treatment is obtained at overflow rates above 1.5 m/h, using reasonably priced, local sources of metal salts in concentrations of 25 to 50 mg/l without polymers.

scholarly journals Inorganic Nitrogen Production and Removal along the Sediment Gradient of a Stormwater Infiltration Basin

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 320
Author(s):  
Qianyao Si ◽  
Mary G. Lusk ◽  
Patrick W. Inglett
Keyword(s):  
Removal Efficiency ◽  
N Mineralization ◽  
Inorganic Nitrogen ◽  
Dry Season ◽  
Pollutant Removal ◽  
Net N Mineralization ◽  
Wet Season ◽  
Inorganic N ◽  
N Removal ◽  
Stormwater Infiltration

Stormwater infiltration basins (SIBs) are vegetated depressions that collect stormwater and allow it to infiltrate to underlying groundwater. Their pollutant removal efficiency is affected by the properties of the soils in which they are constructed. We assessed the soil nitrogen (N) cycle processes that produce and remove inorganic N in two urban SIBs, with the goal of further understanding the mechanisms that control N removal efficiency. We measured net N mineralization, nitrification, and potential denitrification in wet and dry seasons along a sedimentation gradient in two SIBs in the subtropical Tampa, Florida urban area. Net N mineralization was higher in the wet season than in the dry season; however, nitrification was higher in the dry season, providing a pool of highly mobile nitrate that would be susceptible to leaching during periodic dry season storms or with the onset of the following wet season. Denitrification decreased along the sediment gradient from the runoff inlet zone (up to 5.2 μg N/g h) to the outermost zone (up to 3.5 μg N/g h), providing significant spatial variation in inorganic N removal for the SIBs. Sediment accumulating around the inflow areas likely provided a carbon source, as well as maintained stable anaerobic conditions, which would enhance N removal.

Comparative Researches on the Provenances of Suspended Sediments in Different Reaches of Dongtiaoxi and Xitiaoxi Watershed

2014 ◽  
Vol 937 ◽  
pp. 597-603
Author(s):  
Zhao Peng Lu ◽  
Xu Yin Yuan ◽  
Huan Wang ◽  
Hai Long Chen ◽  
Wen Wen Xu
Keyword(s):  
Taihu Lake ◽  
Arable Land ◽  
Suspended Sediments ◽  
Urban Land ◽  
Dry Season ◽  
Wet Season ◽  
Geochemical Model ◽  
Geochemical Parameters ◽  
Main Discharge ◽  
The Difference

Dongtiaoxi and Xitiaoxi river are the two main discharge rivers of Taihu Lake. It is important to research the provenances of suspended sediments (SS) and the difference of the provenances. This paper establishes the geochemical model to quantify the proportions of SS sources with geochemical parameters, and then analyzes the contribution differences of the sources to SS in the basins and its reasons. The results show that the contribution of woodland is highest in the upper reaches of both Dongtiaoxi and Xitiaoxi basin, but the contribution of arable land has more differences. Arable land becomes a major contributor to the midstream of Dongtiaoxi and Xitiaoxi basin, while the contributions of woodland and urban land are larger in Dongtiaoxi basin. The SS contribution of urban land is highest in the downstream of Dongtiaoxi and Xitiaoxi basin, while the contribution of arable land is larger in Dongtiaoxi basin. During wet season and dry season, the differences of the sources contribution variations in Dongtiaoxi basin are not obvious, while that in Xitiaoxi basin are significantly obvious, that is the SS contributions of woodland and urban land in wet season are significantly higher than in dry season, while the contributions of arable land and bank sediment are on the contrary.

scholarly journals Identification Soybean Processed Waste Environmental Impact and Management Alternatives (Case Study City of Jakarta Selatan)

2021 ◽  
Vol 5 (2) ◽  
pp. 122-129
Author(s):  
Naomi Aurora Margareth Br. Simanjuntak ◽  
Alfiyah Najwa ◽  
Muhamad Hisyam Dhiya Ulhaq ◽  
Mutiara Octaviani ◽  
Deni Adnan ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Waste Treatment ◽  
Negative Impact ◽  
Treatment Technology ◽  
Trickling Filters ◽  
Industry Waste ◽  
The People ◽  
Management Alternatives ◽  
Processed Waste

Processed soybeans such as tempeh and tofu are some of the foods that the people of Indonesia favour. The Tempe and Tofu processing factory produce tofu with the essential soybean ingredients as much as 17 kg every day. The tofu production process starts from soybean immersion, grinding, boiling, filtering, compaction, moulding, cutting, to frying tofu. Production activities from the tofu industry will certainly produce solid and wastewater. These wastes can have a negative impact on the environment. Therefore, the waste must be managed and treated correctly to create an environmentally friendly industry and improve environmental quality. Tofu industry waste management and treatment can be done by identifying the generation of waste that is a priority to be treated and choosing waste treatment technology. There are three alternatives for wastewater treatment from the tofu industry: the chlorine in wastewater, ponds by forming biofilms using biofilter media, and Trickling Filters.

scholarly journals THE EFFECT OF SEASONAL VARIATION ON PERFORMANCE OF EGG TYPE POULTRY: A Case Study of Mitchell Farms, Mosogar, Delta State, Nigeria

2021 ◽  
Vol 24 (2) ◽  
pp. 101-105
Author(s):  
E. E. Guobadia
Keyword(s):  
Seasonal Variation ◽  
Feed Intake ◽  
Egg Production ◽  
Management Practices ◽  
Secondary Data ◽  
Dry Season ◽  
Wet Season ◽  
Egg Hatchability ◽  
Significant Difference

The study was designed to find out the effect of seasonal variation on poultry in Delta State of Nigeria. The variables considered were mortality rate, feed intake, egg production and egg hatchability in the wet and dry seasons of the year. Secondary data were also collected from records kept in the farm. Sites 4AHI-BLK,5AKI-BLK, 9H/BF and 10H/BF were used for the study with each having an average of 2,500-3,500 birds of the same breed and sex aged 1-9 weeks and 21-52weeks. The records were grouped into dry season (October-March) and wet season (April-September) covering three years, 1991-1994. The analysis of the result showed that seasonal variation does not have any significant effect (P < 0.05) on mortality and feed intake in the two seasons. However percentage egg production and egg hatchability revealed a significant difference (P < 0.05) between the two seasons, with a mean % egg production and hatchability of 74±.03 and 80.6 in the wet season and 53.67±0.01 and 55.9 respectively in the dry season. Recommendation is therefore made for proper planning which ensures the utilization of wet and dry season management practices to reduce the effect of high humidity and embient temperature on production.

scholarly journals Contrasting patterns of litterfall seasonality and seasonal changes in litter decomposability in a tropical rainforest region

2014 ◽  
Vol 11 (6) ◽  
pp. 7901-7929
Author(s):  
S. A. Parsons ◽  
V. Valdez-Ramirez ◽  
R. A. Congdon ◽  
S. E. Williams
Keyword(s):  
Seasonal Changes ◽  
Biogeochemical Cycles ◽  
Dry Season ◽  
Tropical Region ◽  
Soil N ◽  
Wet Season ◽  
Evergreen Forests ◽  
P Limitation ◽  
Global Trend ◽  
The Difference

Abstract. The seasonality of litter inputs in forests has important implications for understanding ecosystem processes and biogeochemical cycles. We quantified the drivers of seasonality in litterfall and leaf decomposability, using plots throughout the Australian wet tropical region. Litter fell mostly in the summer (wet, warm) months in the region, but other peaks occurred throughout the year. Litterfall seasonality was modelled well with the level of deciduousness of the site (plots with more deciduous species had lower seasonality than evergreen plots), temperature (higher seasonality in the uplands), disturbance (lower seasonality with more early secondary species) and soil fertility (higher seasonality with higher N : P/P limitation) (SL total litterfall model 1 = deciduousness + soil N : P + early secondary sp: r2 = 0.63, n = 30 plots; model 2 = temperature + early secondary sp. + soil N : P: r2 = 0.54, n = 30; SL leaf = temperature + early secondary sp. + rainfall seasonality: r2 = 0.39, n = 30). Leaf litter decomposability was lower in the dry season than in the wet season, driven by higher phenolic concentrations in the dry, with the difference exacerbated particularly by lower dry season moisture. Our results are contrary to the global trend for tropical rainforests; in that seasonality of litterfall inputs were generally higher in wetter, cooler, evergreen forests, compared to generally drier, warmer, semi-deciduous sites that had more uniform monthly inputs. We consider this due to more diverse litter shedding patterns in semi-deciduous and raingreen rainforest sites, and an important consideration for ecosystem modellers. Seasonal changes in litter quality are likely to have impacts on decomposition and biogeochemical cycles in these forests due to the litter that falls in the dry being more recalcitrant to decay.

Reality or myth: “Advanced wastewater treatment technologies cannot be cost competitive with conventional treatment processes”

2011 ◽  
Vol 6 (1) ◽  
Author(s):  
Ali R. Ahmadi Motlagh ◽  
Stephen Lacy ◽  
Madan Arora ◽  
Jim Ross ◽  
Jeff Misenhimer
Keyword(s):  
Wastewater Treatment ◽  
Conventional Treatment ◽  
Treatment Plant ◽  
Advanced Treatment ◽  
Recycled Water ◽  
Treatment Technology ◽  
Treatment Processes ◽  
Treatment Technologies ◽  
Two Alternatives

With shortage of water becoming a major concern in many areas, use of recycled water is a necessity for a growing number of municipalities. This paper describes a case study in which two alternatives were considered for upgrading an existing wastewater treatment plant with the goal of producing recycled water. The first alternative consisted of conventional secondary and tertiary unit processes while the second alternative included the advanced treatment technology of membrane bioreactor (MBR). Also, two alternatives were evaluated for disinfection of recycled water; chlorine gas and UV system. The more advanced treatment technologies (MBR + UV), which produce the higher quality recycled water, resulted in higher cost. The paper discusses the design and project execution approaches as how the more expensive advanced treatment processes were made cost competitive with the conventional treatment processes.

scholarly journals Immature growth performance of three important rubber tree (Hevae brasiliensis) clones in a drought-prone area

2020 ◽  
pp. 469-474
Author(s):  
Sophea Nhean ◽  
Supat Isarangkool Na Ayutthaya ◽  
Rachanee Rathanawong ◽  
Frederic C. Do
Keyword(s):  
Rubber Tree ◽  
Genetic Material ◽  
Dry Season ◽  
Wet Season ◽  
Monthly Basis ◽  
Common Strategy ◽  
Prone Area ◽  
The Difference ◽  
Dehydration Avoidance ◽  
Drought Prone Area

Adaptation of rubber tree clones to water-limited areas and maintenance of trunk radial growth are important keys for performance of genetic material. The rubber farmers need to shorten the interim phases to produce latex, which is considered “immature” phase, i.e. the time without income. The objective of this study was to compare the performance of three important rubber tree clones: GT1, the elder clone as control, which is still widely used in Cambodia and West Africa; RRIM600, the “all-round” clone, the most planted clone in Thailand, the first world producer; and RRIT251, the expanding clone, recommended by the Rubber Authority of Thailand, all in the field condition. The investigation was conducted in a drought-prone area of Northeast Thailand, where the dry season lasts 5 to 6 months. The cumulated growth and the annual growth were analyzed 4.5 years after planting. The trunk girth and height were measured monthly. Main climatic variables were hourly recorded. The year was separated in three periods: the leaves-shed season from January to April, the wet season from May to September, and the dry season with canopy maintenance from October to December. The results showed significant clonal effect on both trunk girth and height; however, with relatively low differences. The trunk girth of clone RRIT251 was about 29 cm and 10% higher than GT1. The difference was not significant in RRIM600. The annual girth increment was mainly located in wet season (63%) without clonal effect. The clonal difference was occurred in the dry season, where RRIT251 was better performed particularly in the leave-shed period preceding wet season. On a monthly basis, the relative trunk girth increment rate was highly negatively related to the vapor pressure deficit. We hypothesized that rubber clones shared a common strategy of dehydration avoidance, while RRIT251 expressed a little less degree of avoidance.

scholarly journals Contaminants of Emerging Concern Removal in an Effluent of Wastewater Treatment Plant under Biological and Continuous Mode Ultrafiltration Treatment

2020 ◽  
Vol 12 (2) ◽  
pp. 725 ◽  
Author(s):  
Cristian Ferreiro ◽  
Iker Gómez-Motos ◽  
José Ignacio Lombraña ◽  
Ana de Luis ◽  
Natalia Villota ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Biological Treatment ◽  
Food Additives ◽  
Treatment Plant ◽  
Pharmaceutical Products ◽  
Contaminants Of Emerging Concern ◽  
Removal Rates ◽  
Wide Range

This work presents a case study of a wastewater treatment plant (WWTP), located in Biscay (Spain), in which the removal of high-occurrence contaminants of emerging concern (CEC) was studied. The existing biological treatment in the WWTP was complemented with a continuous ultrafiltration (c-UF) pilot plant, as a tertiary treatment. Thus, the effect on CEC removal of both treatments could be analyzed globally and after each operation. A total of 39 CEC were monitored, including pharmaceutical products, industrial additives, food additives, herbicides and personal care products. For evaluation of the efficiencies, the removal rates of the biological and of the c-UF treatments, including their variability over a day and a week in relation to the ammonium content, were examined in the influent of the WWTP. In the biological treatment, a wide range of different removal rates was obtained due to the different CEC’s biodegradability and concentration. In UF, lower, but more constant removal rates, were achieved. In addition, the reduction of the general toxicity by the UF treatment in terms of the Microtox® toxicity assay was also evaluated. After UF, all of the samples yielded values of TU50 lower than 1, confirming this result the UF effectiveness for toxicity removal.

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