A condition occurring on trickling filters when the hollow spaces (voids) become plugged to the extent that water passage through the filter is inadequate. Ponding may be the result of excessive slime growths, trash, or media breakdown.
What are the components of a trickling filter?
A trickling filter consists of a fixed bed of rocks, gravel, slag, polyurethane foam, sphagnum peat moss, or plastic media over whichsewage or other wastewater flows downward and causes a layer or film of microbial slime to grow, covering the bed of media.
What is sloughing In trickling filter?
As the biological film continues to grow, the microorganisms near the surface lose their ability to cling to the medium, and a portion of the slime layer falls off the filter. This process is known as sloughing.
What is recirculation in trickling filter?
The recirculation means returning a portion of treated sewage to the treatment unit. By doing so, efficiency of trickling filter improves and it also reduces the load on filter.
What is percolating filter method?
It is an aerobic wastewater treatment method in which the biomass is grown on mass & the sewage is passed over its surface. A trickling filter system is a sort of an attached culture arrangement. It is also termed a percolating filter.
Why does ponding occur at the top of the bed of the filter?
Ponding is normally the result of : (a) excessive organic loading without a corresponding higher recirculation rate, (b) use of media which is too small, (c) clogging of underdrain system, (d) non-uniform media size or breaking up of media, and (e) trash or debris in filter voids.
Which of the FF is a cause of ponding in trickling filters?
Answer: The answer to the question is D. Ponding is a very common condition on trickling filters. Excessive organic loading (resulting in rapid growth of biomass and large sloughing), accumulation of debris and leaves (generally from poor or neglected housekeeping) and/or excessive algae growth cause it.
What is BOD and COD?
Biochemical oxygen demand (BOD) is the amount of oxygen microorganisms require to break down organic materials. In contrast, chemical oxygen demand (COD) is the amount of oxygen required to break down the organic material via oxidation. Read: Biological Oxygen Demand.
What is meant by activated sludge?
The activated sludge is a process with high concentration of microorganisms, basically bacteria, protozoa and fungi, which are present as loose clumped mass of fine particles that are kept in suspension by stirring, with the aim of removing organic matter from wastewater.
Is aeration required in trickling filter?
A trickling filter (TF) is a non-submerged fixed bed reactor consisting of highly permeable packing media in which aerobic condition is maintained via diffusion, forced aeration, natural convection or splashing.
What is the purpose of grit chamber?
Grit chambers are long narrow tanks that are designed to slow down the flow so that solids such as sand, coffee grounds, and eggshells will settle out of the water. Grit causes excessive wear and tear on pumps and other plant equipment.
What is digestion of sludge?
The process of changing organic matter in sludge into a gas or a liquid or a more stable solid form. These changes take place as microorganisms feed on sludge in anaerobic (more common) or aerobic digesters.
What is the purpose of sludge recirculation?
Sludge recirculation is an easy, simple and reliable method for increasing anaerobic digester performance.
What are the 3 stages of filtration?
There are three stages of filtration: mechanical, biological, and UV clarification.
What are the 3 basic method of filtering?
There are several filtration methods : simple or gravity, hot and vacuum filtrations. The selection of the appropriate method is typically dictated by the nature of the experimental situation.
What are the 4 stages of filtration?
The Water Shop uses the Millenium four-stage filtration process for drinking water purity.
- Pre-Filter. The Millennium pre-filter is a sediment/carbon block cartridge.
- Membrane. Water travels from the pre-filter into the membrane.
- Post-Filter. Any tastes or odors remaining in the water will be reduced by the.
- Polishing Filter.
What do you mean by ponding?
Ponding is the (typically) unwanted pooling of water, typically on a flat roof or roadway. Ponding water accelerates the deterioration of many materials, including seam adhesives in single-ply roof systems, steel equipment supports, and particularly roofing asphalt.
What causes ponding?
Ponding water forms when the rooftop doesn’t properly drain, leaving rainwater on the roof for two days or more, despite conditions that allow other areas of the roof to completely dry. Ponding water can affect your roof in many ways.
What is ponding of water?
Water ponding is the accumulation of water on flat surfaces such as slab-on-grade, flat decks, driveways or balconies. This can occur due to water seeping upward from inside (or below) the surface, or its source can be external, such as rainwater.
What happens at ponding time?
Ponding time is the time when rainwater infiltrates from the beginning of infiltration until surface runoff begins. Ponding which is a response to rain when the soil surface exceeds the soil saturation limit is undoubtedly influenced by factors that affect the infiltration rate.
How do you solve ponding water problems?
How To Stop Water Pooling on Flat Roof (Tips + Hacks in 2022)
- Flush Existing Drains.
- Fix Low Spots.
- Add More Drain Lines.
- Install Roof Crickets.
- Re-pitch The Rooftop.
- Replace The Membrane.
- Compress Insulation.