Wastewater Lagoons in a Cold Climate

1987 ◽  
Vol 19 (12) ◽  
pp. 47-53 ◽  
Author(s):  
J. A. Oleszkiewicz ◽  
A. B. Sparling

Severe climate, intermittent rivers and availability of land make facultative lagoon systems the method of choice in treating primarily domestic sewage from smaller municipalities. The lagoons are designed on a recommended maximum load of 55 kgBOD5/ha d to first cell, while the second cell provides storage. The discharge is twice annually and the occurrence of the spring ice break-up odor period is one of the primary criteria limiting this load. Based on full scale performance data, it is demonstrated that, from the standpoint of odor nuisance, the load to the first cell should be kept equal to or less than 35 kg/ha d. Full scale studies of an overloaded lagoon system show the futility of under-ice aeration for odor control. Mechanism of natural odor control during ice break up is elucidated. Upgrading of the overloaded systems or lagoons receiving significant industrial contribution is best achieved by construction of a 3–5 m deep aerated lagoon preceding the two or more facultative cells in series.

2005 ◽  
Vol 51 (9) ◽  
pp. 165-171 ◽  
Author(s):  
S. Wallace ◽  
R. Kadlec

A pilot-scale subsurface vertical-flow wetland system was constructed at the former BP Refinery in Casper, Wyoming in order to determine benzene, toluene, ethylbenzene and xylene (BTEX) degradation rates in a cold-climate application. The pilot system, consisting of 4 cells, each dosed at a nominal flow rate of 5.4 cubic metres per day, was operated between August and December 2002. The pilot tested the effects of wetland mulch and aeration on system performance. Areal rate constants (kA values) were calculated based on an assumed three tanks in series (3TIS). The presence of wetland sod and aeration both improved treatment performance. Mean kA values were 244 m/yr for cells without sod or aeration, and improved to 356 m/yr for cells with sod and aeration. Based on the results of the pilot system, a full-scale wetland system (capable of operating at 6,000 m3/day) was started up in May 2003. The full-scale system achieved permit compliance within one week of startup, but is currently being loaded at only 45% of the design hydraulic load, and 15% of the design BTEX mass load, resulting in a mean kA value of ∼350 m/yr.


2000 ◽  
Vol 41 (1) ◽  
pp. 177-185 ◽  
Author(s):  
G. Andreottola ◽  
P. Foladori ◽  
M. Ragazzi

The aim of this study was to evaluate the performance of a full-scale upgrading of an existing RBC wastewater treatment plant with a MBBR (Moving Bed Biofilm Reactor) system, installed in a tank previously used for sludge aerobic digestion. The full-scale plant is located in a mountain resort in the North-East of Italy. Due to the fact that the people varied during the year's seasons (2000 resident people and 2000 tourists) the RBC system was insufficient to meet the effluent standards. The MBBR applied system consists of the FLOCOR-RMP®plastic media with a specific surface area of about 160 m2/m3 (internal surface only). Nitrogen and carbon removal from wastewater was investigated over a 1-year period, with two different plant lay-outs: one-stage (only MBBR) and two stage system (MBBR and rotating biological contactors in series). The systems have been operated at low temperature (5–15°C). 50% of the MBBR volume (V=79 m3) was filled. The organic and ammonium loads were in the average 7.9 gCOD m−2 d−1 and 0.9 g NH4−N m−2 d−1. Typical carbon and nitrogen removals in MBBR at temperature lower than 8°C were respectively 73% and 72%.


Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7538
Author(s):  
Wenkai Huang ◽  
Wei Hu ◽  
Tao Zou ◽  
Junlong Xiao ◽  
Puwei Lu ◽  
...  

Most existing wall-climbing robots have a fixed range of load capacity and a step distance that is small and mostly immutable. It is therefore difficult for them to adapt to a discontinuous wall with particularly large gaps. Based on a modular design and inspired by leech peristalsis and internal soft-bone connection, a bionic crawling modular wall-climbing robot is proposed in this paper. The robot demonstrates the ability to handle variable load characteristics by carrying different numbers of modules. Multiple motion modules are coupled with the internal soft bone so that they work together, giving the robot variable-step-distance functionality. This paper establishes the robotic kinematics model, presents the finite element simulation analysis of the model, and introduces the design of the multi-module cooperative-motion method. Our experiments show that the advantage of variable step distance allows the robot not only to quickly climb and turn on walls, but also to cross discontinuous walls. The maximum climbing step distance of the robot can reach 3.6 times the length of the module and can span a discontinuous wall with a space of 150 mm; the load capacity increases with the number of modules in series. The maximum load that modules can carry is about 1.3 times the self-weight.


2018 ◽  
Vol 13 (3) ◽  
pp. 589-593 ◽  
Author(s):  
T. Niwa ◽  
R. Yin ◽  
M. H. Oo ◽  
H. Noguchi ◽  
T. Watanabe ◽  
...  

Abstract Application of membrane technology for water reclamation has grown significantly in recent years due to reduced footprint size and more consistent product water quality. For a membrane bioreactor (MBR) system, it is critical for it to be robust to allow membrane systems to operate at higher flux without significant increase of trans-membrane pressure (TMP). A full-scale ceramic MBR system was installed at Changi Water Reclamation Plant (CWRP) as part of an MBR retrofit project to increase treatment capacity without expanding the plant's footprint. The nominal capacity of the ceramic MBR system is 15,000 m3/d. The system has been successfully operating since January 2017 with a net flux of 30–60 L/m2-hr (LMH). Stable operation was observed at nominal production capacity for more than 3 months. During that period, the TMP was stable in the range of 9–14 kPa for Tank A and 10–17 kPa for Tank B. Permeate turbidity was recorded in the range of 0.04–0.06 NTU for both Tank A and Tank B.


Land ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 520
Author(s):  
Guri Venvik ◽  
Floris Boogaard

The rain gardens at Bryggen in Bergen, Western Norway, is designed to collect, retain, and infiltrate surface rainfall runoff water, recharge the groundwater, and replenish soil moisture. The hydraulic infiltration capacity of the Sustainable Drainage System (SuDS), here rain gardens, has been tested with small-scale and full-scale infiltration tests. Results show that infiltration capacity meets the requirement and is more than sufficient for infiltration in a cold climate. The results from small-scale test, 245–404 mm/h, shows lower infiltration rates than the full-scale infiltration test, with 510–1600 mm/h. As predicted, an immediate response of the full-scale infiltration test is shown on the groundwater monitoring in the wells located closest to the infiltration point (<30 m), with a ca. 2 days delayed response in the wells further away (75–100 m). Results show that there is sufficient capacity for a larger drainage area to be connected to the infiltration systems. This study contributes to the understanding of the dynamics of infiltration systems such as how a rain garden interacts with local, urban water cycle, both in the hydrological and hydrogeological aspects. The results from this study show that infiltration systems help to protect and preserve the organic rich cultural layers below, as well as help with testing and evaluating of the efficiency, i.e., SuDS may have multiple functions, not only storm water retention. The functionality is tested with water volumes of 40 m3 (600 L/min for 2 h and 10 min), comparable to a flash flood, which give an evaluation of the infiltration capacity of the system.


2007 ◽  
Vol 55 (11) ◽  
pp. 73-79
Author(s):  
D. Houweling ◽  
F. Chazarenc ◽  
R. Leduc ◽  
Y. Comeau

Tracer studies performed in two aerated facultative lagoons indicate some bypass and an overall hydraulic regime close to completely-mixed. Results were used to calibrate a hydraulic model based on the tanks-in-series approach. The hydraulic model was combined with a simple “death-regeneration” biokinetic model to simulate seasonal nitrification as observed over a three year period. Modifications were made to the hydraulic model to represent the effect of baffle installations to 1) eliminate bypass and 2) impose a plug-flow regime. Simulation results indicate there is some gain to eliminating bypass but that imposing a plug-flow regime would increase biomass washout rates and hinder nitrification.


1981 ◽  
Vol 8 (1) ◽  
pp. 9-15
Author(s):  
D. S. Mavinic ◽  
D. A. Koers

With high-rate activated sludge as feed, various modes of digestion were studied on a laboratory scale at 20, 10, and 5 °C. This study was performed to develop design guidelines, operating criteria, and kinetic coefficients for low-temperature aerobic sludge digestion. To develop a possible scale factor for extrapolation of laboratory results to full-scale conditions, a field evaluation program was conducted to collect and analyze full-scale data from three independent sources.In this manuscript a summary of previously published data, as well as some of the latest research findings, have been presented. In addition, this paper outlines a new design procedure for use in "sizing" a typical aerobic digester; as well, a method for determination of oxygen requirements in the digester tanks is described.This design procedure is based primarily on a graphical solution involving several variables, whereby the percentage reduction of volatile suspended solids is plotted against the product of temperature and sludge age. Included in this presentation is a comparison between the use (and misuse) of kinetic data in traditional design procedures. The design methodology presented has already proven to be a valuable and cost-effective tool, especially for cold-climate package plant design.


Sign in / Sign up

Export Citation Format

Share Document