AEROBIC WASTEWATER TREATMENT SYSTEMS AND HOW THEY WORK - Biological wastewater treatment systems can be efficient and economical technologies for breaking down and removing organic contaminants from heavily organic-laden wastes, such as those produced in the food and beverage, chemical manufacturing, oil and gas, and municipal industries. Aerobic wastewater treatment systems use oxygen-feeding bacteria, protozoa, and other specialty microbes to clean water. These systems optimize the naturally occurring process of microbial decomposition to break down industrial wastewater contaminants so they can be removed. The organic contaminants these microorganisms decompose are often measured in biological oxygen demand, or BOD, which refers to the amount of dissolved oxygen needed by aerobic organisms to break down organic matter into smaller molecules. High levels of BOD indicate an elevated concentration of biodegradable material present in the wastewater and can be caused by the introduction of pollutants such as industrial discharges, domestic fecal wastes, or fertilizer runoff. Because these organisms require oxygen, aerobic systems require some means of supplying oxygen to the biomass by adding wastewater treatment ponds (which work by creating a large surface area for introducing air to the wastewater) and/or by incorporating some type of mechanical aeration device to introduce oxygen into the biomass.

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What Are Aerobic Wastewater Treatment Systems and How Do They Work?

SAMCO

Typically used as a secondary wastewater treatment method after the initial larger contaminants have been settled and/or filtered out, biological wastewater treatment systems can be efficient and economical technologies for breaking down and removing organic contaminants from heavily organic-laden wastes, such as those produced in the food and beverage, chemical manufacturing, oil and gas, and municipal industries.

Anaerobic and aerobic systems are two of the main types of biological wastewater treatment, but this article will focus on “what aerobic wastewater treatment systems are and how they work.”

What is aerobic wastewater treatment?

Aerobic wastewater treatment systems use oxygen-feeding bacteria, protozoa, and other specialty microbes to clean water (as opposed to anaerobic systems that do not need oxygen).

These systems optimize the naturally occurring process of microbial decomposition to break down industrial wastewater contaminants so they can be removed.

The organic contaminants these microorganisms decompose are often measured in biological oxygen demand, or BOD, which refers to the amount of dissolved oxygen needed by aerobic organisms to break down organic matter into smaller molecules.

High levels of BOD indicate an elevated concentration of biodegradable material present in the wastewater and can be caused by the introduction of pollutants such as industrial discharges, domestic fecal wastes, or fertilizer runoff.

How do aerobic wastewater treatment systems work?

Because these organisms require oxygen, aerobic systems require some means of supplying oxygen to the biomass by adding wastewater treatment ponds (which work by creating a large surface area for introducing air to the wastewater) and/or by incorporating some type of mechanical aeration device to introduce oxygen into the biomass.  

Depending on the chemical makeup of the wastewater in relation to the effluent requirements, a biological wastewater treatment system might be composed of several different processes and numerous types of microorganisms.

They will also require specific operational procedures that will vary depending on the environment needed to keep biomass growth rates optimal for the specific microbial populations.

For example, it is often required to monitor and adjust aeration to maintain a consistent dissolved oxygen level to keep the system’s bacteria multiplying at the appropriate rate to meet discharge requirements.

In addition to dissolved oxygen, biological systems often need to be balanced for flow, load, pH, temperature, and nutrients.

Balancing a combination of system factors is where the biological treatment process can become very complex.

Below are examples of some common types of aerobic biological wastewater treatment systems, including a brief description of how they function within an industrial wastewater treatment regimen to give you an idea of the types of technologies and systems that might benefit your industrial facility.

Activated sludge

Used widely used in municipal applications, activated sludge processes occur when wastewaters from the primary treatment phase enter an aeration tank.

After aeration in the presence of suspended (freely floating) aerobic microorganisms, the organic material is broken down and consumed, forming biological solids which flocculate into larger clumps, or flocs.

The suspended flocs enter a settling tank and are removed from the wastewater by sedimentation. Recycling settled solids to the aeration tank controls levels of suspended solids, while excess solids are wasted as sludge.

Activated sludge treatment systems typically have larger space requirements and generate large amounts of sludge, with associated disposal costs, but capital and maintenance costs are relatively low, compared to other options.

Fixed-bed bioreactors, or FBBRs

These systems consist of multiple-chambered tanks in which the chambers are packed tight with porous ceramic, porous foam, and/or plastic media.

Wastewater then passes through the immobilized bed of media. The media is engineered to have a high enough surface area to encourage a robust biofilm formation with long solids lifespan, resulting in low sludge formation and lowest sludge disposal costs.

A well-engineered fixed-bed bioreactor will allow wastewater to flow through the system without channeling or plugging.

Chambers can be aerobic and still have anoxic zones to achieve aerobic carbonaceous removal and full anoxic denitrification at the same time.

More advanced biological processes can be facilitated with these systems (for example, nitrification, denitrification, desalination, sulfide-reduction, and anammox), by having unique bacterial populations colonize the biofilm media in separate tank chambers, which can be uniquely configured to treat your facility’s specific wastewater constituents.

Moving bed bioreactors, or MBBRs

MBBRs typically consist of aeration tanks filled with small moving polyethylene biofilm carriers held within the vessel by media retention sieves.

Today the plastic biofilm carriers come from many vendors in many sizes and shapes, are typically half- to one-inch diameter cylinders or cubes and are designed to be suspended with their immobilized biofilm throughout the bioreactor by aeration or mechanical mixing.

Because of the suspended moving bio-film carriers, MBBRs allow high BOD wastewaters to be treated in a smaller area with no plugging.

MBBRs are typically followed by a secondary clarifier, but no sludge is recycled to the process; excess sludge settles, and a slurry removed by vacuum truck, or settled solids are filter pressed and disposed as a solid waste.

Membrane bioreactors, or MBRs

MBRs are advanced biological wastewater treatment technologies that combine conventional suspended growth activated sludge with membrane filtration, rather than sedimentation, to separate and recycle the suspended solids.

As a result, MBRs operate with much higher mixed liquor suspended solids (MLSS) and longer solids residence times (SRTs), producing a significantly smaller footprint with a much higher quality effluent compared to conventional activated sludge.

MBRs primarily target BOD and total suspended solids (TSS).

MBR system design varies depending on the nature of the wastewater and the treatment goals, but a typical MBR might consist of aerobic (or anaerobic) treatment tanks, an aeration system, mixers, a membrane tank, a clean-in-place system, and either a hollow fiber or flat sheet ultrafiltration membrane.

As a result of its many parts and cleaning processes, MBRs are known for high capital, high operating, and high maintenance costs.

Biological trickling filters 

These filters work by passing air or water through a media designed to collect a biofilm on its surfaces.

The biofilm may be composed of both aerobic and anaerobic bacteria which breakdown organic contaminants in water or air. Some of the media used for these systems include gravel, sand, foam, and ceramic materials.

The most popular application of this technology is municipal wastewater treatment and air remediation to remove H2S at municipal sewer plants, but they can be used in many situations where odor control is important.

How SAMCO can help?

SAMCO has over 40 years’ experience custom-designing and manufacturing biological wastewater treatment systems for a range of industries and applications, so please feel free to reach out to us with your questions. Contact us here to set up a consultation with an engineer or request a quote. We can walk you through the steps for developing the proper solution and realistic cost for your specific water treatment system needs.

To learn more about the services and technologies that SAMCO offers, visit our page on wastewater treatment solutions here.

At SAMCO, we anticipate the needs of industry, and respond with forward-thinking solutions. Our focus on industrial applications began in 1987 with the founding of Northeast equipment supplier and systems servicer CS Kimeric. Acquired from a Western New York soft water provider with over 30 years in the business, CS Kimeric was established to provide specialized service for industrial applications. Over the course of the next decade, it became clear that industrial clients would benefit from working with a partner capable of delivering comprehensive, concept-to-completion solutions. In 1998, founder and CEO Richard Posa established SAMCO as an integrated provider of design, fabrication, startup, and maintenance services. 

Today, SAMCO serves the process water needs of clients across the nation and globe from its headquarters in Buffalo, New York. Leveraging the collective skills of experienced chemical, civil, environmental, electrical, mechanical and process engineers, chemists, and skilled tradesmen, SAMCO blends a culture of teamwork, commitment and passion to help solve your unique industrial water treatment needs.

https://www.samcotech.com/what-are-aerobic-wastewater-treatment-systems-and-how-do-they-work/

TOXIC BENZENE AND PARKED CARS - Benzene is a toxic chemical known to produce a variety of ill health effects, including anemia and cancer (specifically leukemia) in humans. The substance occurs both naturally and as a byproduct of human activities, e.g. as a component of petroleum-based products and products manufactured using benzene as a solvent (such as plastics, synthetic fibers, dyes, glues, detergents, and drugs). It's also a constituent of tobacco smoke. Low levels of benzene are typically present in outdoor air due to automobile exhaust and industrial emissions. Thanks to vapors emitted by household products such as glues, paints, and furniture wax, even higher levels of benzene can sometimes be found in indoor air, especially in new buildings. In most cars, these items are made from plastics, synthetic fabrics, and glues, some of which are manufactured using benzene. Such items may "off-gas" trace amounts of benzene, especially under hot weather conditions. As to car air fresheners, there's precious little information available about the ingredients, though one European study found that some household air fresheners emit measurable amounts of benzene. It's not inconceivable that some car air fresheners do, too. The crucial question is how much. Might all of these potential emitters cumulatively give off enough benzene to harm your health? Most of the published studies wherein benzene levels were measured inside passenger vehicles have been done in traffic. So, while such studies have indeed found that in-vehicle benzene levels can significantly exceed those outside the vehicle, and could pose a human health hazard, this is mainly attributed to the presence of exhaust fumes.

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Toxic Benzene and Parked Cars

by David Emery

This viral message claims car interiors contain toxic levels of cancer-causing benzene emitted by dashboards, car seats, and air fresheners, and recommends opening windows to expel trapped benzene gas before turning on the car air conditioner.

True or false?

·      Description: Online rumor

·      Circulating since May 2009

·      Status: Grain of truth / Overblown (see details below)

·      Example: Email text contributed by Glennis A., May 11, 2009:

Car A/C (Air Conditioning) MUST READ!!!

Please do NOT turn on A/C as soon as you enter the car.
Open the windows after you enter your car and turn ON the air-conditioning after a couple of minutes.

Here's why:

According to a research, the car dashboard, sofa, air freshener emit Benzene, a Cancer causing toxin (carcinogen - take time to observe the smell of heated plastic in your car).

In addition to causing cancer, Benzene poisons your bones, causes anemia and reduces white blood cells.

Prolonged exposure will cause Leukemia, increasing the risk of cancer. May also cause miscarriage.

Acceptable Benzene level indoors is 50 mg per sq. ft.

A car parked indoors with windows closed will contain 400-800 mg of Benzene. If parked outdoors under the sun at a temperature above 60 degrees F, the Benzene level goes up to 2000-4000 mg, 40 times the acceptable level...

People who get into the car, keeping windows closed will inevitably inhale, in quick succession excessive amounts of the toxin.

Benzene is a toxin that affects your kidney and liver. What's worse, it is extremely difficult for your body to expel this toxic stuff. So friends, please open the windows and door of your car - give time for interior to air out - dispel the deadly stuff - before you enter.

Our Analysis

While it isn't one hundred percent false, the above text is a font of misinformation. Don't let it scare you.

Starting with the basics, it's true that benzene is a toxic chemical known to produce a variety of ill health effects, including anemia and cancer (specifically leukemia) in humans.

The substance occurs both naturally (mainly as a component of crude oil) and as a byproduct of human activities, e.g. as a component of petroleum-based products (such as gasoline) and products manufactured using benzene as a solvent (such as plastics, synthetic fibers, dyes, glues, detergents, and drugs).

It's also a constituent of tobacco smoke.

Low levels of benzene are typically present in outdoor air due to automobile exhaust and industrial emissions.

Thanks to vapors emitted by household products such as glues, paints, and furniture wax, even higher levels of benzene can sometimes be found in indoor air, especially in new buildings.

Benzene in Cars

Do automobile dashboards, door panels, seats, and other interior components emit benzene, as claimed in the email?

Most likely.

In most cars, these items are made from plastics, synthetic fabrics, and glues, some of which are manufactured using benzene.

According to scientists, such items may "off-gas" trace amounts of benzene, especially under hot weather conditions.

As to car air fresheners, there's precious little information available about the ingredients, though one European study found that some household air fresheners emit measurable amounts of benzene.

It's not inconceivable that some car air fresheners do, too.

The crucial question is how much.

Might all of these potential emitters cumulatively give off enough benzene to harm your health?

What the Scientists Say

Most of the published studies wherein benzene levels were measured inside passenger vehicles have been done under driving conditions, in traffic.

So, while such studies have indeed found that in-vehicle benzene levels can significantly exceed those outside the vehicle, and could pose a human health hazard, this is mainly attributed to the presence of exhaust fumes.

Also, the amounts of benzene actually detected by researchers, albeit statistically significant, were much, much smaller than the amounts stated in the email.

A 2006 study summarizing all the data collected to date reported in-vehicle benzene levels from exhaust fumes ranging from .013 mg to .56 mg per cubic meter — a far cry from the 400 mg to 4,000 mg per square foot (do they mean cubic foot?) reported in the email.

Benzene Levels in Parked Cars

In the one study, we were able to find that measured benzene levels inside parked cars with their engines turned off.

The results were more benign.

Toxicologists took samples of the air inside both a new and a used vehicle under simulated hot-sunlight conditions, measuring the levels of volatile organic compounds (VOCs) including C3- and C4-alkylbenzenes, and exposing human and animal cells to the samples to determine their toxicity.

Despite the detectable presence of VOCs (a total of 10.9 mg per cubic meter in the new car and 1.2 mg per cubic meter in the old car), no toxic effects were observed.

Apart from noting the slight possibility that allergy-prone individuals might find their condition exacerbated by exposure to such compounds, the study concluded there is "no apparent health hazard of parked motor vehicle indoor air."

When in Doubt, Ventilate

Despite this finding, some drivers may still be concerned about the presence of any benzene vapors inside their car, especially given the World Health Organization's stated position that there is "no safe level of exposure" to the carcinogen.

They may also worry, per the email warning above, that turning on the vehicle's air conditioner might exacerbate their exposure to trapped toxins by recirculating contaminated air.

If that's the case, there's no harm done — and much peace of mind to be gained — by simply opening the windows and ventilating the car before turning it on.

David Emery is a freelance writer and avid chronicler of folklore and popular culture, with a special interest in the quick-fire folklife of the digital age.

Experience

Dubbed About.com's "urban legend guru" by Salon magazine and cited in the New York Times, Christian Science Monitor, Washington Post, the BBC and USA Today, David Emery has more than 18 years' experience as an Internet folklore expert and debunker of urban legends, hoaxes, and popular misconceptions. Other professional credits include stints as a newsroom librarian, staff writer for a TV sitcom, freelance journalist, and contributing editor of a satirical newspaper. Mr. Emery first won recognition in the online universe as an arch commentator on the outer limits of Net culture with Iron Skillet Magazine, "a compendium of offbeat views run through the blender of the author's savage sense of humor ... [with] on-target skewerings of strange ideas" (Houston Chronicle, 1997).

Testimonials

“[Emery is] a strong writer with a bright, amusing style. This fun, informative, and concise site is extremely easy to navigate and a good first step for those new to the subject.” – Brandon Toropov, The Complete Idiot's Guide to Urban Legends (Alpha Books, 2001)

“The best place to track urban legends is the About.com section run by guide David Emery. In addition to his usual smart debunking of various urban legends, he has been tracking rumors about the attacks since Sept. 11. “ – Sree Sreenivasan, “Keeping Track of Rumors and Hoaxes” (Poynter.org, 2002)

“This About.com subsite has been hosted for ten years by David Emery and frankly, he has done a great job. He is passionate about finding and debunking all those rumors, myths, pranks and odd stories. “ – Tim Malone, “Top 10 Sites to Debunk Urban Legends" (Tech Republic, 2008)

"David Emery's urban legend site at About.com has been a reliable source of information for years." – Jan Harold Brunvand, Encyclopedia of Urban Legends, Updated and Expanded Edition (ABC-CLIO, 2012)

Education

Mr. Emery holds a BA in Philosophy.

David Emery

Please join me in what promises to be a constantly entertaining, ever-enlightening exploration into the urban legends and folklore of the digital age.

https://www.thoughtco.com/is-there-toxic-benzene-in-parked-cars-3298894

FIRE FIGHTING SYSTEMS - A fire fighting system is probably the most important of the building services, as its aim is to protect human life and property, strictly in that order. It consists of three basic parts: a large store of water in tanks, either underground or on top of the building, called fire storage tanks; a specialised pumping system; a large network of pipes ending in either hydrants or sprinklers. A fire hydrant is a vertical steel pipe with an outlet, close to which two fire hoses are stored (A fire hydrant is called a standpipe in America). During a fire, firefighters will go to the outlet, break open the hoses, attach one to the outlet, and manually open it so that water rushes out of the nozzle of the hose. The quantity and speed of the water is so great that it can knock over the firefighter holding the hose if he is not standing in the correct way. As soon as the fire fighter opens the hydrant, water will gush out, and sensors will detect a drop in pressure in the system. This drop in pressure will trigger the fire pumps to turn on and start pumping water at a tremendous flowrate. A sprinkler is a nozzle attached to a network of pipes, and installed just below the ceiling of a room. Every sprinkler has a small glass bulb with a liquid in it. This bulb normally blocks the flow of water. In a fire, the liquid in the bulb will become hot. It will then expand, and shatter the glass bulb, removing the obstacle and causing water to spray from the sprinkler.

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An electric fire pump located in a fire fighting pump room.

Fire
Fighting Systems

understandconstruction.com

A fire fighting system is probably the most important of the building services, as its aim is to protect human life and property, strictly in that order.  

It consists of three basic parts:

·        a large store of water in tanks, either underground or on top of the building, called fire storage tanks

·        a specialised pumping system,  

·        a large network of pipes ending in either hydrants or sprinklers (nearly all buildings require both of these systems)

A fire hydrant is a vertical steel pipe with an outlet, close to which two fire hoses are stored (A fire hydrant is called a standpipe in America). 

During a fire, firefighters will go to the outlet, break open the hoses, attach one to the outlet, and manually open it so that water rushes out of the nozzle of the hose.

The quantity and speed of the water is so great that it can knock over the firefighter holding the hose if he is not standing in the correct way.  

As soon as the fire fighter opens the hydrant, water will gush out, and sensors will detect a drop in pressure in the system.

This drop in pressure will trigger the fire pumps to turn on and start pumping water at a tremendous flowrate.

A sprinkler is a nozzle attached to a network of pipes, and installed just below the ceiling of a room.

Every sprinkler has a small glass bulb with a liquid in it. This bulb normally blocks the flow of water.

In a fire, the liquid in the bulb will become hot. It will then expand, and shatter the glass bulb, removing the obstacle and causing water to spray from the sprinkler.

The main difference between a hydrant and a sprinkler is that a sprinkler will come on automatically in a fire.

A fire hydrant has to be operated manually by trained firefighters - it cannot be operated by laymen.

A sprinkler will usually be activated very quickly in a fire - possibly before the fire station has been informed of the fire - and therefore is very effective at putting out a fire in the early stages, before it grows into a large fire.  

For this reason, a sprinkler system is considered very good at putting out fires before they spread and become unmanageable.  

According to the NFPA of America, hotels with sprinklers suffered 78% less property damage from fire than hotels without in a study in the mid-1980s.

FIRE STORAGE TANKS

The amount of water in the fire storage tanks is determined by the hazard level of the project under consideration.  

Most building codes have at least three levels, namely, 

o  Light Hazard (such as schools, residential buildings and offices), 

o  Ordinary Hazard (such as most factories and warehouses), and 

o  High Hazard (places which store or use flammable materials like foam factories, aircraft hangars, paint factories, fireworks factories).  

The relevant building code lists which type of structure falls in each category. 

The quantity of water to be stored is usually given in hours of pumping capacity.

In system with a capacity of one hour, the tanks are made large enough to supply the fire with water for a period of one hour when the fire pumps are switched on.  

For example, building codes may require light hazard systems to have one hour’s capacity and high hazard 3- or 4-hours capacity.  

The water is usually stored in concrete underground tanks.

It is essential to ensure that this store of water always remains full, so it must have no outlets apart from the ones that lead to the fire pumps.

These tanks are separate from the tanks used to supply water to occupants, which are usually called domestic water tanks.

Designers will also try and ensure that the water in the fire tanks does not get stagnant and develop algae, which could clog the pipes and pumps, rendering the system useless in a fire.

FIRE PUMPING SYSTEM

Fire pumps are usually housed in a pump room very close to the fire tanks.

The key thing is that the pumps should be located at a level just below the bottom of the fire tank, so that all the water in the tanks can flow into the pumps by gravity.

Like all important systems, there must be backup pumps in case the main pump fails.

There is a main pump that is electric, a backup pump that is electric, and a second backup pump that is diesel-powered, in case the electricity fails, which is common.

Each of these pumps is capable of pumping the required amount of water individually - they are identical in capacity.

There is also a fourth type of pump called a jockey pump.

This is a small pump attached to the system that continually switches on to maintain the correct pressure in the distribution systems, which is normally 7 Kg/cm2 or 100 psi.

If there is a small leakage somewhere in the system, the jockey pump will switch on to compensate for it. Each jockey pump will also have a backup.

The pumps are controlled by pressure sensors.

When a fire fighter opens a hydrant, or when a sprinkler comes on, water gushes out of the system and the pressure drops.

The pressure sensors will detect this drop and switch the fire pumps on.

But the only way to switch off a fire pump is for a fire fighter to do this manually in the pump room.

This is an international code of practice that is designed to avoid the pumps switching off due to any malfunction in the control system.

The capacity of the pumps is decided by considering a number of factors, some of which are:

·        the area covered by hydrants / standpipes and sprinklers

·        the number of hydrants and sprinklers

·        the assumed area of operation of the sprinklers

·        the type and layout of the building

THE DISTRIBUTION SYSTEM

The distribution system consists of steel or galvanised steel pipes that are painted red. 

These can be welded together to make secure joints, or attached with special clamps. 

When running underground, they are wrapped with a special coating that prevents corrosion and protects the pipe.  

There are basically two types of distribution systems

Automatic Wet systems are networks of pipes filled with water connected to the pumps and storage tanks, as described so far.

Automatic Dry systems are networks of pipes filled with pressurized air instead of water.

   When a fire fighter opens a hydrant, the pressurized air will first rush out.

   The pressure sensors in the pump room will detect a drop in pressure, and start the water pumps, which will pump water to the system, reaching the hydrant that the fire fighter is holding after a gap of some seconds.

   This is done wherever there is a risk of the fire pipes freezing if filled with water, which would make them useless in a fire.

Some building codes also allow manual distribution systems that are not connected to fire pumps and fire tanks.

These systems have an inlet for fire engines to pump water into the system.

Once the fire engines are pumping water into the distribution system, fire fighters can then open hydrants at the right locations and start to direct water to the fire.

The inlet that allows water from the fire engine into the distribution system is called a siamese connection.

In high-rise buildings it is mandatory that each staircase have a wet riser, a vertical fire-fighting pipe with a hydrant at every floor. 

It is important that the distribution system be designed with a ring main, a primary loop that is connected to the pumps so that there are two routes for water to flow in case one side gets blocked.

In more complex and dangerous installations, high and medium velocity water-spray systems and foam systems (for hazardous chemicals) are used. 

The foam acts like an insulating blanket over the top of a burning liquid, cutting off its oxygen. 

Special areas such as server rooms, the contents of which would be damaged by water, usegas suppression systems. 

In these an inert gas is pumped into the room to cut off the oxygen supply of the fire.

When you design a fire fighting system, remember the following:

o  Underground tanks: water must flow from the municipal supply first to the firefighting tanks and then to the domestic water tanks. This is to prevent stagnation in the water. 

o  The overflow from the firefighting to the domestic tanks must be at the top, so that the firefighting tanks remain full at all times. 

o  Normally, the firefighting water should be segregated into two tanks, so that if one is cleaned there is some water in the other tank should a fire occur.

o  It is also possible to have a system in which the firefighting and the domestic water are in a common tank. 

In this case, the outlets to the fire pumps are located at the bottom of the tank and the outlets to the domestic pumps must be located at a sufficient height from the tank floor to ensure that the full quantity of water required for firefighting purposes is never drained away by the domestic pumps. 

The connection between the two tanks is through the suction header, a large diameter pipe that connects the all the fire pumps in the pump room. 

Therefore, there is no need to provide any sleeve in the common wall between the two firefighting tanks.

o  The connection from each tank to the suction header should be placed in a sump; if the connection is placed say 300mm above the tank bottom without a sump, then a 300mm high pool of water will remain in the tank, meaning that the entire volume of the tank water will not be useable, to which the Fire Officer will object.

o  Ideally the bottom of the firefighting pump room should be about 1m below the bottom of the tank. This arrangement ensures positive suction for the pumps, meaning that they will always have some water in them.

o  All pump rooms should without fail have an arrangement for floor drainage; pumps always leak. 

o  The best way to do this is to slope the floor towards a sump, and install a de-watering pump if the water cannot flow out by gravity.

o  In cases where there is an extreme shortage of space, one may use submersible pumps for firefighting. This will eliminate the need for a firefighting pump room.

o  Create a special shaft for wet risers next to each staircase. About 800 x 1500 mm should suffice. It is better to provide this on the main landing rather than the mid landing, as the hoses will reach further onto the floor.

This is a site that explains the art and science of building construction in great clarity and detail.  Our goal is to make you understand concepts in building construction.
Written by architects and engineers, the content on the site is actually a result of accumulated years of work experience at building construction sites and design offices.  This expert knowledge of building construction is not available in textbooks!
We also take great pains to ensure that our quality of writing is of a high standard.  We aim to take complicated situations and make them simple and clear, as well as to provide content that is interesting to industry experts and newcomers alike.  Do let us know where we succeed - and where we fail - in this task.

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