Sand filter media are beds of granular material, or sand, drained from
underneath so that pretreated wastewater can be treated, collected and
distributed to the land application system. They are normally used
to polish effluent from septic tanks or
other treatment processes before it is
distributed on the land. All on-site
systems are no-discharge, meaning
the wastewater must stay in the
system and not leave the property.The wastewater cannot enter surface
water, streams, ditches or any water
resources. After the filtrate is collected
by the sand filters under drains, it is
then disposed of by a soil absorption
system.
Intermittent sand filters provide biodegradation or decomposition of wastewater constituents
by bringing the wastewater into close contact with a well developed aerobic biological
community attached to the surfaces of the filter media. This process requires unsaturated
downward flow of the effluent through a filter media which may be a mineral sand or
equivalently sized crushed glass meeting one of the media.
The Sand filter media is contained in a watertight vessel either below the surface of the ground or wholly
or partially elevated in a containment vessel. Proper function requires that the influent to the
filter be distributed over the media in controlled, uniform doses. In order to achieve accurate
dosing, these systems require a timer controlled pump with associated pump tank, electrical
components, and distribution network to deliver a minimum of 12 doses per day spread evenly
over a 24 hour period. The effluent is collected in the bottom of the sand filter and discharged
either by gravity or pressure to a suitable disposal component, usually a sub-surface drainfield.
This technology is used on sites with high groundwater levels and/or shallow soil conditions
where treatment must be accomplished before disposal. Intermittent sand filters are also used
as part of a mitigation strategy when horizontal separations are reduced.
Media Specifications -- The filter media must meet either the Coarse Sand Media or
the Sand Filter Media specifications for particle size gradation detailed in Appendix
A. Filter media used in constructing a sand filter must be accompanied with a written
certification from the supplier that the sand fully conforms to one of the media.
Treated Wastewater (Filtrate) Collection and Discharge -- Filtrate may be collected and
discharged from the bottom of the sand filter by either a gravity flow underdrain, or pumped
from a pump basin. When sand filters are membrane-lined, gravity flow underdrains must exit
through a boot. The boot and exit pipe must be watertight.
Sand filter media Filteration
Filtration is the last unit process in pretreatment of
water
Water flows either by gravity or under pressure
through a filter media like sand or anthracite
Suspended solids and flocs formed previously by
coagulation and flocculation are retained on the
filter surface
Once the pressure drop exceeds the set limit, the
filer bed is cleaned by back washing the media
by reversal of flow of water
The filter is now ready for use.
Showing posts with label Specification. Show all posts
Showing posts with label Specification. Show all posts
Elegant Swimming Pool Sand Filter Specification
Swimming Pool sand Filters
Keeping a pool clean calls for a multi-level maintenance strategy. The pools grate and skimmer
baskets will catch the bigger, more visible items that float by. Micro-scopic bacteria require
sanitizing chemical additives. For most of the other stuffthe little particles that can make your
water look cloudy and disagreeablethe filter is the best defense.
There are three types of filter systems: sand, cartridge, and diatomaceous earth (DE). All three
systems are effective and will keep your water clean. The cartridge filter requires less
maintenance, so it is rising in popularity.
Sand
Though cartridge filters are popular, Swimming Pool sand Filters are still very common. They rely on very fine
particles of sandfiner than what youd find at the beachto catch small particles you dont want
in your water. Compared to other types of filters, sand is a little less effectivethat is, it will let
some smaller particles pass through into the pool. In addition, sand needs to be cleaned
manually every few weeks and changed at least once a season.
Cartridge
These are like the water filter you may have under your kitchen
sink. Water passes through the filter and catches small, offending
particles. Generally, cartridge filters have more square feet of
catching area than sand filters, so they need to be cleaned less
often; high-end models will last a whole season. And they are
easy to clean: Just hose them off. In terms of effectiveness, they
are between sand and DE filters for particle-catching ability. They
work best with low water pressure, so they partner well with
energy- saving pump systems.
DE (Diatomaceous Earth)
These Swimming Pool sand Filters contain a fine powder of diatomaceous earth, which
is actually fossilized exo-skeletons of tiny diatoms. The powder
coats the filter and works like a sieve to remove particles. This
type of filter is the most effective at keeping the water clean.
Whichever type of filter you choose, good maintenance will help
keep your whole pump/filtration system working efficiently. To
gauge when its time to clean the filter, keep an eye on the pressure, or psi, level in your pool.
Take note of the pressure level when the filter is clean. When you notice that the pressure has
risen about 10 psi, its time to clean the filter. The water circulation system for all types of filters
works best at low water pressure levels.
Filtermaster Sand Filters are manufactured with
high grade breglass and resins utilising the latest
engineering techniques ensuring high quality and
superior strength for long life and durability.
Keeping a pool clean calls for a multi-level maintenance strategy. The pools grate and skimmer
baskets will catch the bigger, more visible items that float by. Micro-scopic bacteria require
sanitizing chemical additives. For most of the other stuffthe little particles that can make your
water look cloudy and disagreeablethe filter is the best defense.
There are three types of filter systems: sand, cartridge, and diatomaceous earth (DE). All three
systems are effective and will keep your water clean. The cartridge filter requires less
maintenance, so it is rising in popularity.
Sand
Though cartridge filters are popular, Swimming Pool sand Filters are still very common. They rely on very fine
particles of sandfiner than what youd find at the beachto catch small particles you dont want
in your water. Compared to other types of filters, sand is a little less effectivethat is, it will let
some smaller particles pass through into the pool. In addition, sand needs to be cleaned
manually every few weeks and changed at least once a season.
Cartridge
These are like the water filter you may have under your kitchen
sink. Water passes through the filter and catches small, offending
particles. Generally, cartridge filters have more square feet of
catching area than sand filters, so they need to be cleaned less
often; high-end models will last a whole season. And they are
easy to clean: Just hose them off. In terms of effectiveness, they
are between sand and DE filters for particle-catching ability. They
work best with low water pressure, so they partner well with
energy- saving pump systems.
DE (Diatomaceous Earth)
These Swimming Pool sand Filters contain a fine powder of diatomaceous earth, which
is actually fossilized exo-skeletons of tiny diatoms. The powder
coats the filter and works like a sieve to remove particles. This
type of filter is the most effective at keeping the water clean.
Whichever type of filter you choose, good maintenance will help
keep your whole pump/filtration system working efficiently. To
gauge when its time to clean the filter, keep an eye on the pressure, or psi, level in your pool.
Take note of the pressure level when the filter is clean. When you notice that the pressure has
risen about 10 psi, its time to clean the filter. The water circulation system for all types of filters
works best at low water pressure levels.
Filtermaster Sand Filters are manufactured with
high grade breglass and resins utilising the latest
engineering techniques ensuring high quality and
superior strength for long life and durability.
Luxury Swimming Pool Filter Specification
Filters can be above-ground or in-ground pool models, or both. Some models are also multipurpose pool/spa/aquarium filters. Popular brands include Intex, Hayward,Pentair (Triton, Purex), Sta-Rite (now merged with Pentair), Waterway, Jandy, Pac-Fab (Nautilus), Waterco, and Doughboy. Prices range from under $ 50 to a few hundred dollars; depending on the type, size and brand.
How to Choose the Right Swimming Pool Filter
All filters should have a flow-rate (GPH, gallons per hour) rating. The larger the filter, the higher the flow-rate it can handle. The filter's flow-rate should be the
same or higher than the pump's flow-rate. A larger flow-rate filter has less resistance, putting less strain on the pump.
Filters are sometimes specified according to pool size. For example, a filter can be specified for a maximum pool size of 19,000 gallons and assuming an 8 hour
turnover time. This means that the filter can handle 19,000 gallons in 8 hours, or 19,000 / 8 = 2,375 GPH.
There are three main types of Swimming Pool Filter
: cartridge, sand, and diatomaceous earth. When choosing a filter, filtration performance and initial cost are important considerations.
Maintenance effort and cost are also important. These are more difficult to know beforehand as they depend on how dirty the pool water is (pollen count, number of
people, sun tan lotion used, amount of algae-promoting sunlight, etc), and the size of the filter relative to the size of the pool. The filter-change numbers given
below are based on manufacturers' recommendations and user reviews, and will vary depending on actual conditions.
The filter should be washed or replaced, when the filter begins to be blocked by trapped dirt. This is determined by comparing either water flow-rate or filter water
pressure, against the numbers when the filter was new. Details will be in the manufacturer's owner's manual.
The filter should have a built-in pressure gauge. Cheaper cartridge filters do not have a pressure gauge. It's therefore necessary to eye-ball the cartridge condition,
water flow-rate, or pool clarity.
Cartridge Swimming Pool Filter
These are the cheapest type of filter and are often supplied together with above-ground pools.
Advantages
Low initial cost.
Easy to install and set up.
Easy to maintain, just clean or replace the cartridge, but with daily or weekly effort.
Medium filtration performance (size of dirt particles trapped).
Disadvantages
Frequent filter washings (every day or week) and replacement (every few weeks or months) required. Shops might not sell filters all year round (online sales websites
are one solution), and the cost of replacement filters adds up.
Filter needs to be manually hosed down for cleaning. There is no backwash setting. Special filter cleaning solutions are available for more thorough cleaning.
Slow Sand Filters
This traditional design of filter typically has a bed 1 to 2 metres deep, and can be rectangular or cylindrical in cross section; it is used primarily to treat surface
water. Slow sand filters have a number of unique qualities:
Use biological processes and are non-pressurized systems.
Do not require chemicals or electricity to operate.
Cleaning is traditionally by mechanical scraper; however, some operators use "wet harrowing", where the sand is scraped while still under water, and the water used for
cleaning is drained to waste.
Maximum required throughput of water is achievable with one or more beds out of service.
Require relatively low feed turbidity levels.
Produce water at a slow, constant flow rate and are usually used in conjunction with a storage tank for peak usage.
How to Choose the Right Swimming Pool Filter
All filters should have a flow-rate (GPH, gallons per hour) rating. The larger the filter, the higher the flow-rate it can handle. The filter's flow-rate should be the
same or higher than the pump's flow-rate. A larger flow-rate filter has less resistance, putting less strain on the pump.
Filters are sometimes specified according to pool size. For example, a filter can be specified for a maximum pool size of 19,000 gallons and assuming an 8 hour
turnover time. This means that the filter can handle 19,000 gallons in 8 hours, or 19,000 / 8 = 2,375 GPH.
There are three main types of Swimming Pool Filter
: cartridge, sand, and diatomaceous earth. When choosing a filter, filtration performance and initial cost are important considerations.
Maintenance effort and cost are also important. These are more difficult to know beforehand as they depend on how dirty the pool water is (pollen count, number of
people, sun tan lotion used, amount of algae-promoting sunlight, etc), and the size of the filter relative to the size of the pool. The filter-change numbers given
below are based on manufacturers' recommendations and user reviews, and will vary depending on actual conditions.
The filter should be washed or replaced, when the filter begins to be blocked by trapped dirt. This is determined by comparing either water flow-rate or filter water
pressure, against the numbers when the filter was new. Details will be in the manufacturer's owner's manual.
The filter should have a built-in pressure gauge. Cheaper cartridge filters do not have a pressure gauge. It's therefore necessary to eye-ball the cartridge condition,
water flow-rate, or pool clarity.
Cartridge Swimming Pool Filter
These are the cheapest type of filter and are often supplied together with above-ground pools.
Advantages
Low initial cost.
Easy to install and set up.
Easy to maintain, just clean or replace the cartridge, but with daily or weekly effort.
Medium filtration performance (size of dirt particles trapped).
Disadvantages
Frequent filter washings (every day or week) and replacement (every few weeks or months) required. Shops might not sell filters all year round (online sales websites
are one solution), and the cost of replacement filters adds up.
Filter needs to be manually hosed down for cleaning. There is no backwash setting. Special filter cleaning solutions are available for more thorough cleaning.
Slow Sand Filters
This traditional design of filter typically has a bed 1 to 2 metres deep, and can be rectangular or cylindrical in cross section; it is used primarily to treat surface
water. Slow sand filters have a number of unique qualities:
Use biological processes and are non-pressurized systems.
Do not require chemicals or electricity to operate.
Cleaning is traditionally by mechanical scraper; however, some operators use "wet harrowing", where the sand is scraped while still under water, and the water used for
cleaning is drained to waste.
Maximum required throughput of water is achievable with one or more beds out of service.
Require relatively low feed turbidity levels.
Produce water at a slow, constant flow rate and are usually used in conjunction with a storage tank for peak usage.
Subscribe to:
Posts (Atom)