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Open-Loop Multi-Well Groundwater Heat Pump Systems
Published in Vasile Minea, Heating and Cooling with Ground-Source Heat Pumps in Cold and Moderate Climates, 2022
The following major modifications have been implemented in 1984: (i) production well pump operation was modified from on/off to variable-speed control. Under this approach, the pump would operate continuously, eliminating the start/stop of the original design; this modification eliminated one of the two major sources of oxygen entering the system and constant surging of the well that occurred at each pump-off cycle has been eliminated, possibly reducing sand production from the aquifer; (ii) elimination of the settling tank closed the second major avenue for oxygen intrusion into the system; with the installation of a variable-speed drive for the production well pump, the tank would be unnecessary for groundwater flow control; if sand continued to be a problem, the use of a centrifugal sand separator was recommended in lieu of the settling tank; and (iii) installation of heat exchangers to isolate the groundwater from the balance of the mechanical system was the most important recommendation.
A pilot study of deep-well recharge by Amsterdam Water Supply
Published in Peter J. Dillon, Management of Aquifer Recharge for Sustainability, 2002
S.W. van Duijvenbode, T.N. Olsthoorn
The mobile cleaning robot travels across the bottom of the supply channel and removes the top layer by suction (Fig. 4). This layer (filter sludge) is composed of a mixture of fine sand and organic material. The removed layer is fed through a sand separator placed on the back of the robot. After separation, slurry is transported to the waterside and the sand put back in to the filter. In August 1996, this mobile slurry removing system came into use (Van Duijvenbode 1997). By using this mobile robot (1996–1998) the increase of hydraulic resistance in the slow sand filter could be limited (fig. 3).
Drip irrigation
Published in Mohammad Albaji, Introduction to Water Engineering, Hydrology, and Irrigation, 2022
Components (listed in order from water source)Pump or pressurized water sourceWater Filter(s) – Filtration Systems: Sand Separator like Hydro-Cyclone, Screen filters, Media Filters, Automatic self-cleaning water filtersFertigation Systems (Venturi injector) and Chemigation Equipment (optional)Backwash Controller (Backflow Preventer)Pressure Control Valve (Pressure Regulator)Main Line (larger diameter Pipe and Pipe Fittings)Hand-operated, electronic, or hydraulic Control Valves and Safety ValvesSmaller diameter polytube (often referred to as “laterals”)Poly fittings and Accessories (to make connections)Emitting Devices at plants (ex. Emitter or Drippers, micro-spray heads, inline drippers, trickle rings)Note that in Drip irrigation systems Pumps and valves may be manually or automatically operated by a controller.
Supervisory fuzzy control system for biological processes in sequencing wastewater batch reactor
Published in Urban Water Journal, 2020
The Swarzewo WWTP is located in Northern Poland and is a typical SBR plant. The average WWTP wastewater influent is about 6000 m3/day. The wastewater treatment involves mechanical, biological, and chemical processes. Sewage solids are separated in the mechanical part (grid, screen, grit chamber, sand separator), while the chemical part is used to remove phosphorus from wastewater using coagulants. Nutrient removal is performed by four SBRs. SBR capacities are as follows: SBR 1, 2, 3 are of 5100 m3, and SBR 4 is of 4948 m3. They operate independently and in parallel. The air for the reactors is supplied by two separate aeration systems. SBRs 1, 2 and 3 are supplied by the first aeration system, and SBR 4 by the second aeration system. This system is considered in this paper.