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With cystitis, cyst- refers to the bladder, and -itis refers to inflammation, therefore

cystitis describes an inflamed bladder, which is usually the result of a bacterial infection,

but also can result from fungal infections, chemical irritants, foreign bodies like kidney

stones, as well as trauma.

Now a urinary tract infection, or UTI, is any infection of the urinary tract, which

includes the upper portion of the tract—the kidneys and ureters, and the lower portion

of the tract—the bladder and urethra.

So cystitis, when it's caused by an infection, is a type of lower UTI.

Lower UTIs are almost always caused by an ascending infection, where bacteria typically

moves from the rectal area to the urethra and then migrate up the urethra and into the

bladder.

Having said that, on rare occasions, a descending infection can happen as well where bacteria

starts in the blood or lymph and then goes to the kidney and makes its way down to the

bladder and urethra.

Normally, urine is sterile, meaning bacteria doesn't live there; the composition of urine,

which has a high urea concentration and low pH, helps keep bacteria from setting up camp.

Also, though, the unidirectional flow in the act of urinating also helps to keep bacteria

from invading the urethra and bladder.

Some bacteria, though, are better surviving in and resisting these conditions, and can

stick to and colonize the bladder mucosa.

E. coli accounts for the vast majority of UTIs, also though, other gram negative bacteria

that can infect the bladder include Klebsiella, Proteus, Enterobacter, and Citrobacter species.

On the other hand, gram positive bacteria can also cause problems, like Enterococcus

species, and Staphylococcus saprophyticus, which is actually the second most common cause

after E. coli and particularly affects young, sexually active women.

That said, as far as risk factors go, sexual intercourse is a major risk factor, because

bacteria can be introduced into the urethra, and this is sometimes even referred to as

"honeymoon cystitis".

In general, women are at higher risk for cystitis than men, due to having a shorter urethra.

This is because bacteria that are ascending up the urethra don't have to travel as far.

Also, in post-menopausal women there is a decrease in estrogen levels which causes the

normal protective vaginal flora to be lost, increasing the risk of a UTI.

Other risk factors include presence of a Foley catheter in the urethra, which can introduce

pathogens.

Another risk factor is having diabetes mellitus, since people with diabetes tend to have hyperglycemia

or high blood glucose.

Normally with an infection, neutrophils move out of the circulatory system toward the infection,

called diapedesis, as well as carry out phagocytosis, but hyperglycemia inhibits these processes,

making those neutrophils less effective at killing invaders.

Also, infant boys with foreskin around their penis have a slightly higher risk of a UTI

compared to infant boys who've have had a circumcision.

A final important risk factor is impaired bladder emptying causing urinary stasis, which

means urine tends to sit still, allowing bacteria the chance to adhere and colonize in the bladder.

Symptoms of cystitis include suprapubic pain, which is pain in the lower abdomen, dysuria,

which is painful or difficulty urinating, as well as frequent urination and urgency,

meaning you have to go a lot and you have to go now, and typically the urine voids are

small in volume.

Having said that, symptoms can differ by age; infants might have a fever, become fussy,

and feed poorly, whereas elderly patients might feel fatigue, become incontinent, or

even develop delirium.

Symptoms that're not typically present with lower UTIs are systemic signs like fevers

and nausea or vomiting, as well as pain at the costovertebral angle which is the angle

formed on either side of the back between the twelfth rib and the vertebral column,

are all usually absent in a lower UTI, and if they do occur though, this might suggest

an upper urinary tract infection, which includes an infection of the kidneys themselves.

If a urinalysis is done, there may be signs of inflammation like pyuria, the presence

of white blood cells in the urine, which can make the urine appear cloudy.

Having a couple white blood cells in the urine can be normal, but it'd be considered abnormally

high if there are more than 5 white blood cells per high powered field on microscopy

or more than 10 white blood cells per mL on a hemocytometer.

Similarly, a dipstick test that shows the presence of leukocyte esterase, which is an

enzyme created by leukocytes, or white blood cells.

It might also be positive for nitrites, since gram negative organisms like E coli. convert

nitrates in the urine to nitrites, but it's worth remembering that not all uropathogens

are able to do that.

Alright and finally a urine culture is the gold standard for diagnosis, and it's considered

positive if it shows more than 100,000 colony-forming units per mL from a clean catch urine sample,

although a lower number of colony-forming units per mL might still indicate an infection

depending on the source of the specimen and the specifics of the clinical scenario.

And remember that this test assumes that the bacteria that grows is a known bacterial cause

of UTIs and that the patient has clinical symptoms.

Now, if there is pyuria but the urine culture doesn't reveal a bacteria, this is known

as sterile pyuria, and it suggests urethritis, inflammation of just the urethra, as opposed

to cystitis.

Isolated urethritis is most commonly caused by Neisseria gonorrhoeae and Chlamydia trachomatis,

both of which are sexually transmitted infections.

For a UTI, imaging studies can also be helpful, for example, a renal ultrasound can be used

for children who may have a kidney malformation which could contribute to developing a UTI.

In addition, a voiding cystourethrogram or VCUG might be used, which is where an individual

is given a radiocontrast liquid and fluoroscopy which are like real-time Xrays, and then they

watch how that fluid gets urinated out.

This is particularly helpful in children with severe or recurrent UTIs to detect evidence

of vesicoureteral reflux, which is the retrograde movement of urine from the bladder back up

into the ureters and kidneys.

The degree of vesicoureteral reflux can vary and it is an important risk factor for kidney

scarring with a UTI.

Finally, in some situations, renal scintigraphy using DMSA, which is a radionuclide, sometimes

called a DMSA scan, can be used to detect evidence of kidney scarring.

Treatment for a lower UTI is usually antibiotics targeted to the bacterial cause and symptoms

usually clear up within a few days as the urine becomes sterile, at the same time pain

medication may also sometimes be given.

Preventing UTIs mainly involves drinking lots of fluids to help flush out bacteria that

may try to ascend up the urethra and emptying the bladder as often as possible especially

relevant for women after sexual activity, and finally maintaining good hygiene like

wiping from the urethra to the rectum, all of which are aimed at preventing fecal bacteria

from making it up the urethra.

Alright, as a quick recap—cystitis is inflammation of the bladder usually caused by bacterial

infection, which makes it a type of lower urinary tract infection.

E coli's by far the most common culprit, and risk factors include female gender, sexual

intercourse, having catheters, diabetes mellitus, having penile foreskin in infant boys, and

urinary stasis.

For more infomation >> Lower urinary tract infection (cystitis) - causes, symptoms, treatment & pathology - Duration: 8:22.

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4.10 Semi Centralized Treatment, Aerobic Technologies - Duration: 11:38.

Now we will look at the aerobic technologies, which can be used as stand-alone systems

or to polish the effluent of anaerobic units.

Aerobic systems are biological systems which rely on the action of bacteria

needing oxygen to live, like us.

Thus, in all of them oxygen provision is a key aspect.

Without sufficient oxygen, the environment becomes anaerobic,

which leads to processes such as described in the last module.

Some aerobic technologies try to imitate nature, such as the "waste stabilization ponds", or

the "constructed wetlands".

Some of these are more engineered, such as the "trickling filter" or the "activated

sludge".

Let's start with the waste deposition ponds, or lagoons.

It is a system that consists in a succession of ponds

with different functions.

First one anaerobic pond, then one or two facultative ponds,

and finally, one or two maturation ponds.

Let's look in more detail at the differences between these three types of ponds.

The anaerobic pond is the deepest, with a depth of two to five meters,

and also the smallest.

It is highly loaded because it receives the rawest water.

The anaerobic pond has a hydraulic retention time from one to three days,

and its main function is sedimentation and anaerobic stabilization of sludge, thus,

settling.

The facultative pond or facultative ponds if they are several, are shallower.

Usually, less than 1.5 meters, but large.

The idea here is to maximize the oxygen supply either through algae, wind, or artificial

aeration.

The hydraulic retention time there is longer: from ten to twenty days.

Here, the main function is the aerobic degradation of suspended and dissolved matter,

thus, degradation.

Finally, the maturation ponds are even shallower, usually less than one meter, but large.

The hydraulic retention time is about ten days.

Here the main function is the final sedimentation of suspended solids,

the bacterial mass, and pathogens, thus polishing.

Waste stabilization ponds can treat high strength wastewater

to a high quality effluent.

They are generally reliable and good functioning and inexpensive, compared to either centralized

options.

However, they require a lot of space and may generate bad odors,

especially the anaerobic pond, if poorly designed.

It requires expert design and supervision, especially to avoid short-circuiting,

in which case, the effluent goes from the inlet to the outlet without

mixing properly, that is, not staying through the intended

retention time.

Besides, if they work at best in warm climates, waste stabilization ponds are not always appropriate

for colder climates.

This picture shows large waste stabilization ponds

for the city of Cuenca, in Ecuador.

A way to increase the performance of waste stabilization ponds

is to provide artificial aeration, which is done in Cuenca in the first pond,

upstream of this picture.

It is also a good way to upgrade the ponds when then reach design capacity,

especially extension, is not always easy.

In aerated ponds, mechanical aerators provide oxygen

and keep the aerobic organisms suspended to achieve a high rate of organic degradation.

Increased mixing and aeration means that the ponds can be deeper

and tolerate much higher organic loads than the maturation pond.

The depth may be from two to five meters and a retention time from three to twenty

days.

In some cases, it can even replace the anaerobic pond,

thus avoiding the bad odors that anaerobic ponds may generate.

The downside of it is that aeration implies a high energy consumption,

and thus costs, and requires a constant source of electricity.

Interruption of electricity service may cause the pond to turn anaerobic,

thus changing completely the inner biological processes.

We will now have a look at another family of treatment technologies: the "constructed

wetlands".

"Constructed wetlands" aim to replicate the naturally occurring processes

of a natural wetland, marsh or swamp.

We distinguish three types: the "free water surface constructed wetland",

the "horizontal subsurface flow constructed wetland",

and the "vertical flow constructed wetland".

Let's start with the "free water surface constructed wetland".

In that case, the water slowly flows through the wetland,

particles settle, and pathogens are eliminated through the combined action of sun, settling,

adsorption, and predation from higher organisms.

The organisms and plants utilize the nutrients.

This style of constructed wetland is commonly used as a polishing step

after secondary or tertiary treatment processes.

It is only appropriate for low strength wastewater.

This is a really important fact.

The depth of the water is ten to 45 cm above ground level.

Wastewater needs to be well distributed at the inlet.

Good operation and maintenance is needed for it not to turn into a mosquito breeding

area, and to avoid short-circuiting.

Let's look now at the "horizontal subsurface flow constructed wetland".

Its performance regarding reduction of BOD, suspended solids, and pathogens

is higher than in the freewater surface constructed wetlands,

and it does not have the mosquito problem as the water flows only under the surface,

as its name indicates.

As in the previous technology, the good distribution of the influent at the

inlet is very important.

The gravel bed is between 50 cm and one meter deep.

The water level is maintained at 5 to 15 cm below the surface.

As wastewater flows horizontally through the basin,

the filter material filters out particles.

It acts both as a filter and as a fixed surface upon which bacteria can attach, forming large

biofilms.

The plant roots play an important role in maintaining permeability in the filter.

It is very important to have a good primary treatment

before the wetland.

Otherwise, the risk of clogging will be very high.

Expert follow-up is necessary to monitor the plants,

especially the startup periods.

As a final remark, we have to mention that the wetlands need a lot of space,

generally a surface of about five to ten square meters per person equivalent.

This picture illustrates the last type of constructed wetland,

the "vertical flow constructed wetland", which is, of course, difficult to differentiate

from outside.

This is the most sophisticated and performance type of wetland

By injecting the wastewater from above the whole surface,

the distribution is greatly improved.

The water flows down and is collected by a drainage system.

The important difference between vertical and horizontal wetlands

is not simply the direction of the flow path, but rather, the aerobic conditions.

The wastewater is applied intermittently, four to ten times a day.

Thus, the filter goes through stages of being saturated and unsaturated,

and accordingly, different phases of aerobic and anaerobic conditions.

With this regime, there is less plugging risk than in horizontal subsurface flow wetland.

Other than that, the treatment processes are the same as in

the horizontal flow wetland.

Because of the mechanical dosing system, this technology is most appropriate where

trained maintenance staff, constant power supply, and spare parts are

available.

Constructed wetlands can reach a good performance with processes close to nature.

However, one has to be aware of the risk of clogging

and the management of the plants, especially the startup and maintenance,

and beware high ammonia levels which may prevent the plants from growing

properly.

In all cases, a good primary treatment is crucial.

Before finishing this module, we will look at two higher end technologies

which we may call Conventional: the "trickling filter", and the "activated

sludge".

These systems are really performant in developed countries,

but imply high capital costs, operation and maintenance by skilled personnel,

and a constant source of energy.

The "trickling filter" is a fixed bed biological reactor

that operates mostly under aerobic conditions.

After primary treatment, wastewater is continuously trickled

or sprayed through the filter, for example, through a rotating sprinkler.

Organics are degraded by the biofilm covering the filter material.

The filter is usually from one to 2.5 meter high,

but some filters may reach a height up to 12 meters.

Adequate airflow is important to ensure sufficient treatment performance

and prevent odors.

The air can circulate vertically through the filter.

The advantage of a trickling filter over the technologies presented before

is the small land requirement; however, flies and odors are often problematic.

The "activated sludge system" is the best known and most widespread in Western

countries under different forms, such as sequencing

batch reactor, oxidation ditches, moving beds, or membrane

bioreactors.

It makes use of highly concentrated micro-organisms to degrade organics and remove nutrients,

leading to a high quality effluent.

To maintain aerobic conditions and to keep the activated sludge suspended,

a continuous and well-timed supply of oxygen is required.

Aeration and mixing can be provided by pumping air or oxygen into the tank

or by surface aerators.

Agglomerations of sludge particles called flux

form in the aerated tank and are removed in a settler

called in that case "secondary clarifier".

We are now at the end of this module on aerobic treatment technologies.

We saw very different technologies that can all perform well,

but have different requirements.

To sum up, we can say that the main decision factors are:

the availability of space, financial resources, skills, and electricity.

For more infomation >> 4.10 Semi Centralized Treatment, Aerobic Technologies - Duration: 11:38.

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3.5 Water Treatment [Maryna Peter (EAWAG)] - Duration: 14:15.

Here is your source water.

How do we make it to look so?

And even if looks so, is it really safe?

During this lecture, we will find out about different water treatment steps, processes

and technologies, understand basic principles behind most commonly used technologies.

We will also discuss advantages, disadvantages and limitations of each treatment process.

All water treatment methods can be divided in five major groups which can function as

a single step treatment or should be applied as part of a large multi-stage treatment.

The five groups of methods are structured around the type of contaminants removed by

the method.

Those groups are clarification which is removal of particulate matter, inactivation of microorganisms

also called disinfection, desalination, and reduction of concentrations of geogenic and

anthropogenic contaminants to meet water quality guidelines.

A meaningful combination of technologies is in most cases necessary to achieve the WHO

water quality standards for safe drinking water.

The choice of technologies or its combinations we make depends on the many factors including

available water resources, their quality and seasonality, legal requirements, scale, space,

financial resources, local availability of products, consumables and skills as well as

available energy sources.

The purpose of clarification is to remove as much as possible particulate material.

The conventional treatment systems usually apply coagulation/flocculation combined with

sedimentation or filtration.

Rapid sand filtration without coagulation is used as well on large centralized drinking

water treatment plants or community supplies.

In community supplies, roughing filtration has been used successfully as efficient and

low maintenance pre-treatment.

Coagulation is usually a pre-treatment step.

Its goal is to change the fine dispersed particles into larger agglomerates that can be removed

by sedimentation or filtration or both.

In coagulation process, a metal salt such as aluminium or iron salts are added to water

containing dispersed often negatively charged particles.

Aluminium or iron ions destabilize the particles by neutralizing their charge.

Water is being mixed rapidly and pH might need a correction.

The destabilized particles form flocks which grow larger during slow mixing and finally

settle down or can be easier filtered out.

Another method of reducing particulate matter content is a rapid sand filtration.

Water passes through the filter media which is coarse or medium sized sand, which is loaded

over the more coarse gravel layer.

During filtration, solids get trapped, settle or adsorb onto the sand material.

After trapped material accumulated in the filter layers, the filter requires backwashing

– reverse flow of water to remove accumulated material.

The filters are operated at linear velocity of 1-40 m/h, which is considerably higher

than in slow sand filters which we discuss later.

The filter can be constructed with locally available resources and does not require consumables,

but proper design, adequate operational parameters and maintenance are crucial for good performance.

For a rather turbid waters, roughing filters can be used prior to rapid or slow sand filtration

or disinfection.

Differently sized coarse material is used in roughing filters.

The size decreases in the direction of flow.

Gravel from riverbed, broken stones, rocks or bricks, plastics, burnt charcoal or coconut

fibre can be used as filtration media.

There are different configurations of roughing filters: up-flow, down-flow or horizontal

flow.

In an up-flow filter you see here, water moves from down to top and the retained solids accumulate

predominantly in the bottom of the filter.

They can be flushed out by reversing the flow or simply draining the filter.

They are quite simple to maintain, do not require any chemicals and have low operational

costs.

Filter design, maintenance practices and raw water quality fluctuations can influence the

performance to a large extent.

Disinfection of drinking water ensures that bacteria viruses and protozoa have been inactivated

or removed from water so they do not longer pose health risk.

Disinfection is always done after clarification and not before, as particles reduce the efficiency

of many disinfectants.

Disinfection by chlorination is most commonly used method.

Chlorine or sodium hypochlorite can also be produced on-site by hypochlorite generators

by electrolysis of salt.

Ozone and UV light inactivate microorganisms while slow sand filtration and membranes filtration

are based on filtration purely or combined with biological processes.

When chlorine is dissolved in water, it forms equilibrium between the chlorine Cl2, hypochlorous

acid HOCl and hydrochloric acid HCl by this reaction forming:

When chlorine is added to water, it reacts first with reduced compounds and is being

destructed.

At a higher dose, it reacts also with organic matter and nitrogen species to form chloro-organic

and chloramine compounds, which at higher dose of chlorine are partly destructed.

Breakpoint is the point at which complete oxidation of all chloramine species occurred.

Figure summarizes the processes occurring during breakpoint chlorination.

In short, at first chlorine residual increases proportionally to the amount of chlorine added

until the mole ratio of ammonia to chlorine is about 1.

Beyond that, addition of chlorine reduces total chlorine residual due to oxidation of

some chloramine species.

Breakpoint (point C) is the point at which complete oxidation of all chloramine species

occurred.

The location of this point depends on the presence of organic matter, nitrogen and reduced

inorganic ions.

After the breakpoint is reached, free chlorine residual proportionally increases with the

chlorine dose.

After the breakpoint is reached, free chlorine residual proportionally increases with the

chlorine dose.

The part of chlorine which participates in disinfection and is called chlorine demand.

The part which remains in water after chlorine demand is satisfied is called total chlorine.

The free chlorine is chlorine which is present in water in form of hypochlorous acid HOCl

or hypochlorite ion OCl-.

Free chlorine inactivates microorganisms or kills them during a defined period of time,

called contact time.

Chlorine residual is the chlorine which remains in water after the disinfection process has

been predominantly completed and acts as a safeguard against additional microbial contamination

that could be introduced in the distribution network or at the point of use.

Recommended residual chlorine concentration is about 0.5 mg/L of free chlorine which should

be applied to water during at least 30 min.

Chlorine dose is being expressed in concentration multiplied by contact time, called Ct value.

Ct99 means the concentration and time required to kill 99 % of target microorganisms.

IN case of bacteria, the Ct values are low, indicating the inactivation of bacteria occurs

relatively fast and at low concentration.

The time and concentration are considerably higher to inactivate viruses, and very high

for protozoa, indicating that chlorination is not very efficient for protozoa inactivation.

Cryptosporidium oocysts are resistant to chlorine which often does not provide sufficient level

of inactivation to protect from a disease.

Presence of particulate matter in water leading to high turbidity of water compromise chlorination

and water has to be clarified before it can be disinfected with chlorine.

There are different forms of chlorine available, and it can even be produced on site by electrolysis

of salt and water.

The choice of the most appropriate form of chlorine will depend on such factors as scale

and water volume which needs to be treated, skills available, safety management practices

and power supply reliability.

Ozone is highly effective oxidant, not only disinfecting water but also reducing color,

micro pollutants content and other organic contamination.

It is however expensive and does not provide residual protection.

Due to high costs and relative complexity it is usually not used in the developmental

or emergency context.

In contrary, UV disinfection is cheap and relatively simple.

It inactivates microorganisms by damaging their DANN and RNA.

In contrary to chlorination it is also efficient against protozoa.

No supply of chemicals is also an advantage of the method.

However, it does not provide residual protection, requires reliable power supply and frequent

cleaning of the UV lamps which are the source of UV light.

As well as in case of chlorination, it is sensitive to turbidity and water should be

clarified before UV treatment.

Slow sand filters are operated at slower filtration rates of 0.1-0.3 m/h compare to rapid sand

filters which are commonly operated at 1-40 m/h.

Slow filtration rates allow development of a biological activity within the filter.

Thus the slow sand filtration is a combination of different biological and physical processes

including Mechanical trapping, Adsorption or attachment, Predation and Natural death

leading to reduction of solids but also micro and macro organisms .Slow sand filters are

usually down-flow filters and are operated by gravity.

Each filter requires ripening period of few days to few weeks, until removal rates stabilize.

Mainly the top layer of the slow sand filter contains a diverse microbiological community

and particles which is also called schmutzdecke, where inactivation of microorganisms occurs.

The technology is simple, low cost and has a long lifespan, but requires large area and

is sensitive to mal-operation or during the periods of excessive turbidity or algal matter

in inflow.

During membrane filtration was is driven by pressure difference between the feed water

and filtrate through a filter with pores of a defined size range.

usually polymeric membranes and sometime ceramic membranes are used.

Microfiltration has pores in the size of bacteria or high and removes them and particulate matter

by siue exclusion.

Ultrafiltration membranes are more tight and remove also viruses which is the size of 20-80

nm.

Nanofiltration requires considerable higher pressure as the pores are small and is capable

of retaining macromolecules and larger ions.

Small ions such as salt ions can be removed by reverse osmosis, requiring even higher

pressure.

For disinfection purposes, ultrafiltration membranes are most common as an effective

barrier against pathogenic microorganisms and particles.

Different configurations of membranes are available.

In drinking water supply hollow fiber membranes are commonly used.

Spiral wound elements – so flat membrane is rolled together with a spacer- are more

often used in desalination processes.

Flat sheet membrane modules are more often used in wastewater treatment in membrane bioreactors.

Membranes need to be frequently backflushed to remove a layer of particles or microorganisms

accumulating on the surface of the membrane.

This layer is also called fouling layer.

The drinking water filtration systems offer constant and reliable operation, which however

requires high degree of automation, reliable power supply and relatively high costs.

There are also gravity driven systems on the market and in development, more suitable for

remote applications.

Desalination is used to remove salt from sea or brackish water.

If a semipermeable membrane is installed between pure and saline water containers, pure water

be drawn by saline water creating osmotic pressure.

In order to overcome this osmotic pressure, external pressure which is higher than osmotic

pressure, needs to be applied.

Seawater has an osmotic pressure of about 25 bar.

Thus RO systems are operated at 30-70 bar to achieve movement of pure water from saline

water through the membrane.

Thus, high pressure pumps and good power supply are required, as well as pretreatment to protect

membranes from fouling.

Chemical contaminants are either naturally occurring chemicals in rocks and soils such

as F and As or synthetic chemicals introduced into environment through industrial waste

and wastewater, agricultural practices or untreated municipal wastewater.

Adsorption on granular activated carbon, sometimes ozonation as well as nanofiltration or RO

are common methods to reduce concentrations to the acceptable level.

It is quite complex and costly processes and it is advisable to look for other water sources

if this is possible if concentrations of synthetic chemicals are too high.

Fluoride and arsenic are most commonly occurring geogenic chemicals which pose a health risk.

There are few methods based on adsorption, coagulation, ion exchange and membranes to

reduce concentrations of these chemicals.

All of them have advantages and disadvantages and no best option exist yet.

There is a large variety of different treatment technologies and part of these we have not

considered here.

Some processes are still in development or few promising systems still exist as pilots.

Nevertheless in this course we considered major conventional drinking water treatment

steps which include clarification and disinfection.

Disinfection is not efficient if water is turbid, and thus clarification needs to be

done before.

Geogenic and anthropogenic contamination of water require special additional treatment

steps, which adds complexity to the system Desalination of sea water is complex, has

high energy demand and often only appropriate in cases were ultimately no other water source

is available.

So, we clarified and disinfected this water.

Let's drink it!

For more infomation >> 3.5 Water Treatment [Maryna Peter (EAWAG)] - Duration: 14:15.

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Lung Cancer Symptoms and Treatment Facts to Know - Duration: 8:14.

Lung Cancer Symptoms and Treatment Facts to Know

Your lungs are an essential part of your respiratory system.

The air that enters through your nose and mouth travels through the trachea until it reaches both of your bronchi, and finally arrives to your lungs.

Lung cancer symptoms can prove deadly.

And, thats why its important to catch them early.

When you breathe in, your lungs fill with air.

This is how you acquire oxygen.

When that air is released, your body releases carbon dioxide.

But how do lung cancer symptoms occur? Everything starts with the cells that are found in the various tissues and organs of your body – in this case, the lungs.

These cells divide to form new cells.

When they're damaged or grow old, they are replaced by other cells.

Sometimes, however, the process can get out of control and produce an excess of new cells for renewal.

This is how tumors form.

Non-small cell lung cancer is the most common type of cancer that many lung cancer symptoms can lead to.

Types of cancer.

Squamous cell carcinoma: This type of cancer originates in the squamous cells, which are thin, flat cells that are similar to fish scales.

Medically, this is known as squamous cell carcinoma.

Large cell carcinoma: This type originates from several different types of large cells.

Adenocarcinoma: This type of cancer arises in the cells that line the alveoli and create substances like mucus.

Uncommon types: Pleomorphic carcinoid tumors, carcinoma of the salivary gland, and unclassified carcinomas.

See also: 8 common cancer symptoms that most people ignore.

Risk factors.

People who smoke are 90% more likely to get lung cancer.

And, don't forget that inhaling second-hand smoke is just as bad as if you were smoking.

Additionally, the inhalation of substances like arsenic, silicon, or chromium is another risk factor.

Diagnosis.

But, the following lung cancer symptoms stand out.

Constant or worsening cough, Chest pain, Trouble breathing, Cough associated with blood or phlegm that's rust-colored, Constant feeling of fatigue, Hoarseness, Weight loss for no apparent reason, Infections like recurring bronchitis and pneumonia, A whistle in the chest.

Additionally, when lung cancer spreads to other parts of the body, you may experience the following:.

Yellowing of the skin, if the cancer spreads to your liver, Bone pain, Headaches, Weakness in the arms and legs, Dizziness, Seizures, Swollen lymph nodes due to a build-up of cells in your immune system.

Also, if these symptoms continue for more than three weeks it's essential that you visit your doctor for a chest x-ray.

Based on your x-ray results, the doctor may request your detailed medical history and perform a physical examination along with other lab tests.

Detection.

This consists of searching for the disease before a patient has any symptoms.

Physical exam: A doctor may check your overall health to see if there are any lumps or anything else out of the ordinary.

Your habits and previous disease history or treatments will be taken into account.

Laboratory tests: Samples of blood, urine, tissue, and other materials that may show signs of cancer are taken.

Imaging: This procedure allows the doctor to obtain images of your body's internal areas.

Genetic testing: These tests search for genetic mutations that could be related to different types of cancer.

Note: Also, it's important that your doctor authorizes all procedures for detecting cancer.

Because, they may not all be useful and could even pose certain risks.

Treatment.

Surgery: An operation that removes the cancerous tissue.

Chemotherapy: The use of medications in pill form or intravenously that reduce or eliminate the cancer.

Radiotherapy: Cancer cells are targeted with high intensity radiation.

Targeted therapy: The use of medications to block the spread of cancer cells.

Prevention.

Avoid smoking and breathing second-hand smoke, Increase your consumption of fruits and vegetables, Exercise regularly, Don't burn wood in your home, as it can release harmful substances, Avoid very industrialized areas, Reduce alcohol consumption, Have an annual medical checkup to detect any abnormalities.

And, don't forget: it's better to be safe than sorry.

Never ignore lung cancer symptoms; its better to see a doctor right away.

For more infomation >> Lung Cancer Symptoms and Treatment Facts to Know - Duration: 8:14.

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Healthwatch: New Treatment For Prostate Cancer - Duration: 3:10.

For more infomation >> Healthwatch: New Treatment For Prostate Cancer - Duration: 3:10.

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What Is The Best Treatment For An Eating Disorder? - Duration: 4:55.

For more infomation >> What Is The Best Treatment For An Eating Disorder? - Duration: 4:55.

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Breast Cancer: The Different Types, Symptoms and Treatment - Duration: 8:10.

Breast Cancer: The Different Types, Symptoms and Treatment

Breast cancer is a chronic illness that occurs when the mammary cell tissues start to change and grow uncontrollably.

These cells continue forming a conglomerate of cells known as a tumor, which can be benign or malignant depending on the way it develops.

If the cells continue growing and are able to spread to other parts of the body, its a malignant tumor.

Types of breast cancer Breast cancer can develop through an invasive or non-invasive form.

If the cancer is invasive, it spreads to the adjacent tissue while the non-invasive form of cancer only develops in the milk ducts and lobules.

  Knowing that the breast zone is where the tumors form, we can distinguish the following types of breast cancer: Ductal carcinoma Ductal carcinoma is the most frequent type of breast cancer.

It starts in the cells that cover the insides of the milk ducts.

If it only develops in the duct, its ductal carinoma in situ (DCIS).

On the other hand, if the cancer spreads outside of the duct, its called invasive ductal carcinoma.

Lobular carcinoma Lobular carcinoma is a type of cancer that develops in the mammary lobules.  Other types In some cases, though they are infrequent in comparison to ductal and lobular carcinoma, breast cancers can also be: medullary, mucinous, tubular, metaplastic or papillary breast cancer.

Causes of breast cancer Typically, a high number of breast cancer cases are a result of gene mutations that happen after birth.

Hereditary factors are less frequent, but they can occur when genetic changes are passed down in a family from one generation to the next.

Aside from family history, its important to highlight that the risk of getting breast cancer increases after reaching the age of 50.

This is especially true if theres a family history of ovarian cancer or late menopause.

Other risk factors are:   Obesity, Alcoholism, Exposure to a ionizing radiation, Undergoing hormonal replacement therapy, Early onset of menstruation.

Breast cancer symptoms In the majority of cases, breast cancer doesnt show obvious symptoms in its initial stages.

In light of this, its crucial to regularly check your breasts at home (self-check) as well as with a healthcare professional.

As the cancer develops further, symptoms can include: Hard, painless lump in armpit zone, with a jagged outline.

Changes in the shape, form or texture of the breasts or nipple.

Formation of a palpable lump or nodule, normally painless.

Foul-smelling liquid emitting from the nipple that can be bloody, yellow or greenish.

In cases of male breast cancer, the cancer can cause pain and sensitivity in the breasts in addition to lump formations.

  The symptoms of an advanced cancer include: Skin ulcers, Bone pain, Breast pain, Weakness and tiredness, Significant weight loss, Inflammation of the lymph nodes in the underarm area.

Diagnosis Diagnosing breast cancer starts with a physical exam. Then, it continues to an examination of both breasts, the underarm area, the neck and the thorax.

If there are any reasons to suspect the illness or if the patient shows important risk factors, a medical specialist can preform a series of tests that help confirm the cancer.

Among these are: Mammography: For detecting suspicious zones in the breast by using X-rays.

Magnetic resonance imaging (MRI): Uses a electromagnetic field in order to obtain images that aims to accurately identify tumors or study abnormal changes in the mammogram.

Breast ultrasound: Carried out with mammograms and they help determine if tumors are liquid or solid.

Breast biopsy: Using methods like a needle, image-guided biopsy, stereotactic or open biopsy.

Computerized tomography: Determines if the cancer has spread outside of the mammary tissue.

Biopsy of the sentinel lymph node: Aims to identify if the cancerous cells have spread to the lymph nodes.

Treatment The treatment for breast cancer takes several factors into consideration, such as: the type of cancer, the stage of the cancer, the sensitivity to certain hormones and if the cancer produces an excess of a protein called HER2/neu.

Several of the most important treatments are: Chemotherapy: A method which utilizes medication to destroy cancerous cells.

Radiotherapy. Aims to destroy cancerous tissue.

Surgery to remove cancerous tissue: If the breast lump is removed, its known as a lumpectomy. Meanwhile, a mastectomy is the removal of the entire breast and possibly neighboring zones, as well.

Targeted therapy: Hormonal treatment is an example of such therapy.

Its used to block certain hormones that stimulate the growth of malignant cells.

It uses medication to attack the gene changes in cancerous cells.

After receiving the treatment best suited for their cases, some women continue on medication for some period of time. No matter what, all patients should follow medical guidelines for undergoing the relevant tests for monitoring cancer relapse or growth of a different kind of breast cancer.

References Cáncer de mama (2009) MedlinePlus Enciclopedia médica en español.

Información general sobre el cáncer del seno (mama) (2010) Instituto Nacional del Cáncer.

Featured image courtesy of © wikiHow.com.

For more infomation >> Breast Cancer: The Different Types, Symptoms and Treatment - Duration: 8:10.

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Baystate Medical's Dr. Heba Wassif on Breast Cancer Treatment and Heart Disease | Connecting Point - Duration: 8:25.

>>> IN MEDICAL NEWS TONIGHT, WE TAKE A LOOK AT THE CONNECTION

BETWEEN CERTAIN BREAST CANCER TREATMENTS CAUSING AN INCREASED

RISK OF HEART DISEASE FOR SOME PATIENTS.

THE AMERICAN HEART ASSOCIATION RECENTLY RELEASED A STATEMENT ON

THE CONNECTION, AND CAROLEE MCGRATH SAT DOWN WITH

NON-INVASIVE CARDIOLOGIST DR.

HEBBA WASIF FROM BAY STATE MEDICAL CENTER TO LEARN MORE.

>> THE EMERGING PARADIGM, FOR THREE REASONS, THERE ARE COMMON

RISK FACTORS BETWEEN BREAST CANCER AND CARDIOVASCULAR

DISEASE, LIKE A SEDENTARY LIFESTYLE, CERTAIN DIETS,

EXCESSIVE MEATS, FOR EXAMPLE, SMOKING THAT HAS SOME

ASSOCIATION ALSO WITH BREAST CANCER.

SO THE DISEASE, BOTH DISEASES CAN EXIST IN THE SAME PERSON, SO

A PERSON CAN BE SUFFERING FROM BABIES AS WELL AS CARDIOVASCULAR

DISEASE.

THE SECOND REASON IS THERE ARE MANY TREATMENT OPTIONS NOW FOR

BREAST CANCER THAT HAVE SOME CARDIOVASCULAR TOXICITY THAT I

BELIEVE WE'LL BE DISCUSSING LATER ON.

SO IT'S IMPORTANT TO KNOW WHAT AN INDIVIDUAL'S UNDERLYING

CARDIOVASCULAR RISK IS.

THE THIRD OBVIOUSLY THAT IF YOU HAVE UNDERLYING CARDIOVASCULAR

DISEASE, THAT MAY DETERMINE OR DIRECT SOME OF YOUR TREATMENT

OPTIONS FOR BREAST CANCER.

>> SO WHAT TYPES OF TREATMENTS ARE WE TALKING ABOUT THIS WOULD

BE THE MOST ADEGREESIVE AND CAUSE PROBLEMS WITH THE HEART?

>> ONE OF THE MOST AGGRESSIVE TREATMENTS IS A GROUP OF DRUGS,

THERE ARE SEVERAL OF THEM IN THE GROUP, SOME CAUSE MORE

CARDIOTOXICITY THAN OTHERS.

>> EXPLAIN THAT.

>> FOR THE LAY PERSON, CARDIOTOXICITY, BECAUSE AS THESE

DRUGS ARE TOXIC AND KILL THE BREAST CANCER CELLS, THEY ALSO

KILL THE MYO CARDIAL CELLS, THE CELLS OF THE HEARTS.

THEY HAVE THE SAME IMPACT, SO THEY INTERACT WITH THE D.N.A.

IN A SIMILAR FASHION THAT THEY

WOULD DO WITH THE TUMOR CELLS.

BUT HERE NOW WE'RE TALKING ABOUT A LIVING HEART CELL.

AND THEREFORE IT CAN POTENTIALLY CAUSE WEAKNESS OF THE HEART

MUSCLE.

THESE DRUGS WERE USED FROM THE EARLY 70'S.

IT WASN'T UNTIL ALMOST 10 YEARS LATER THAT WE DISCOVERED SUCH

THESE TOXICITIES, SO TO SAY. AND WE'VE ALSO DISCOVERED THAT

IT'S SOMEWHAT DOSE DEPENDENT.

AND I WILL QUALIFY THAT STATEMENT, THAT THE I'MER THE

DOSE THE MORE RISK FOR THE HEART MUSCLE.

HOWEVER, THERE'S SOME INDIVIDUALS THAT ARE MORE

SUSCEPTIBLE EVEN AT VERY LOW DOSES, THEY CAN POTENTIALLY HAVE

PROBLEMS WITH THE HEART MUSCLE.

>> WHAT KINDS OF CONDITIONS ARE THOSE INDIVIDUALS IN?

THEY ALREADY HAVE UNDERLYING FACTORS FOR HEART DISEASE?

>> EXACTLY, SO IF THEY HAVE UNDERLYING CARDIOVASCULAR

DISEASE OR IF THEIR HEART MUSCLE IS BORDER LINE WEAK, SO WE

DEFINE A STRONG HEART MUSCLE IN THE WORLD OF MEDICINE IS A HEART

MUSCLE THAT PUMPS ABOUT 60% OF THE BLOOD.

IF YOUR HEART MUSCLE IS BORDER LINE, 50 TO 55%, THEN WE'RE

STARTING AT A WEAKER HEART MUSCLE, THAT CAN POTENTIALLY BE

AT RISK.

AND SOME OF IT IS ALL -- IT'S A WORLD OF UNCERTAINTIES.

BUT WE CAN ONLY TRY TO FIND WHAT ARE THE POSSIBLE ASSOCIATIONS

THAT WOULD INCREASE THE RISK, IDENTIFY THEM, AND THEN MODIFY

WHAT WE DO TO MINIMIZE THAT RISK.

SO IF AN INDIVIDUAL IS OVER 60 YEARS OLD, THEY HAVE TWO OR MORE

CARDIOVASCULAR RISK FACTORS, THEY HAVE A WEAK HEART MUSCLE,

AS I MENTIONED, LIKE A BORDER LINE HEART MUSCLE, THEN WE HAVE

TO MAYBE USE LESS AGGRESSIVE THERAPIES.

OR DO CONTINUOUS MONITORING AT THE BEGINNING OF THE TREATMENT,

AS THE TREATMENT PROGRESSES, AND EVEN AFTER THE TREATMENT IS

TERMINATED BECAUSE SOME OF THESE EFFECTS COULD BE VERY LATE AFTER

THE TREATMENT HAS ENDED.

>> WHEN WOMEN HEAR BREAST CANCER, YOU KNOW, IT'S AN

AUTOMATIC, AS IT SHOULD BE, YOU KNOW, YOU'RE FRIGHTENED, YOU'RE

SO WORRIED ABOUT YOUR FUTURE, YOUR CHILDREN, YOUR HUSBAND.

AND WHAT THE MEDICAL OUTCOME WILL BE.

SO I'M SURE PEOPLE ARE SAYING, YOU KNOW, GIVE METHE STRONGEST

TREATMENT POSSIBLE BECAUSE I WANT TO GET RID OF THIS.

BECAUSE YOU HAVE TO TREAT IT AGGRESSIVELY.

>> ABSOLUTELY.

AND THAT'S NOT HAVING SAID THAT BECAUSE OF THE CONCERN OF

CARDIOVASCULAR RISK OR CARDIOTOKS ISITY, THAT DOESN'T

MEAN THAT WE SHOULD HOLD TREATMENT FOR BREAST CANCER.

YOU HAVE TO TREAT THE CANCER IF IT'S AGGRESSIVE, YOU'RE MORE

LIKELY TO DIE FROM BREAST CANCER THAN DIEING FROM CARDIOVASCULAR

DISEASE.

SOME OF THESE POSSIBILITIES MAY BE LONG TERM.

AND BECAUSE WE HAVE LONG-TERM SURVIVORS, WE ARE SEEING MORE

WOMEN THAT ARE SURVIVING BREAST CANCER, WHICH IS AN AMAZING

ENDEAVOR THAT HAS BEEN ACHIEVED OVER THE LAST 25 YEARS MARKS THE

MORTALITY FROM BREAST CANCER HAS BEEN REDUCED SIGNIFICANTLY.

WE'RE SEEING WOMEN THAT ARE NOW DYING AS OLDER WOMEN FROM

CARDIOVASCULAR DISEASE, WHO HAD BREAST CANCER.

NOT FROM THE RECURRENCE OF THE BREAST CANCER, BUT RATHER FROM

CARDIOVASCULAR DISEASE.

SO IT'S IMPORTANT TO IDENTIFY WHO IS AT RISK FIRST, AND IT IS

AN EVOLVING FIELD WHERE THERE'S A LOT OF WORK THAT'S CURRENTLY

BEEN DONE.

AND IT'S ALSO BEEN IDENTIFIED AS A UNIQUE SUB SPECIALTY OF

CARDIOLOGY WHICH IS ALMOST NEW IN EXISTENCE OVER THE LAST FEW

YEARS.

>> GIVE US THE NUMBERS AS FAR AS THE MORTALLY RATES FOR HEART

DISEASE VERSUS BREAST CANCER.

>> TO PUT THINGS INTO PERSPECTIVE, THERE ARE MORE

WOMEN LIVING WITH CARDIOVASCULAR DISEASE IN THE U.S. THAN THERE

ARE WOMEN WITH BREAST CANCER.

ALMOST 48 MILLION WOMEN WITH CARDIOVASCULAR DISEASE, AND ONE

OUT OF THREE WOMEN WILL DIE FROM CARDIOVASCULAR DISEASE.

AND THAT'S INCLUDING STROKE AS WELL.

ONE OUT OF 31 WOMEN WILL DIE FROM BREAST CANCER.

SO WOMEN ARE MORE LIKELY TO DIE FROM HEART DISEASE THAN BREAST

CANCER.

BUT THIS IS AGAIN WHERE WE'RE IDENTIFYING AWE BREAST CANCERS

IN ALL ITS STAGES AND ALL ITS FORMS AS WELL AS CARDIOVASCULAR

DISEASE.

IT DOESN'T SPEAK FOR THE PARTICULAR INDIVIDUAL.

>> HOW DO YOU WORK WITH THE ONCOLOGIST, WHEN YOU HAVE A

PATIENT WHO HAS HEART DISEASE WHO IS ALSO BEING TREATED FOR

BREAST CANCER, TELL ME HOW THAT RELATIONSHIP HAS TO WORK TO BEST

BENEFIT THE PATIENT.

>> AS I SAID, THIS IS AN EMERGING PARADIGM, AND IT'S AN

EVOLVING COLLABORATION NOW BETWEEN CARDIOLOGISTS AND

ONCOLOGISTS.

THE ONCOLOGIST IS THE PRIMARY TREATING PHYSICIAN, THEY

IDENTIFY WHAT IS THE MOST APPROPRIATE THERAPY FOR THE

PATIENT.

BUT THEY WORK HAND IN HAND WITH THE CARDIOLOGIST TO FIRST

MONITOR THE PATIENTS FROM A CARDIOVASCULAR STANDPOINT, FOR

EXAMPLE, IF THE HEART MUSCLE IS RELATIVELY WEAK TO START WITH,

THEN MAYBE INITIATING CERTAIN THERAPIES MAY BE ADVICABLE.

IF HEART WEAKNESS OCCURS DURING THE THERAPY, AJUSTMENT OF THE

TREATMENT OPTIONS IS WARRANTED.

AND THIS CONTINUOUS MONITORING BY CARDIAC ECHO CARD YOG REAF,

WHICH IS THE ULTRASOUND FOR THE MART MUSCLE, I VERY --

IS VERY IMPORTANT.

IT'S A COLLABORATION OF THE BEGINNING, MIDDLE OF THERAPY AND

EVEN AFTER THE THERAPY IS TERMINATED.

>> I KNOW YOU'RE A MEDICAL DOCTOR, BUT I HAVE TO IMAGINE

THAW SEE THE EMOTIONAL SIDE OF YOUR PATIENTS.

>> SLEUMENT.

>> HERE YOU HAVE BREAST CANCER AND NOW YOU'RE AT HIGH RISK FOR

A HEART, SOME SORT OF HEART FAILURE OR HIGH RISK OF HEART

DISEASE.

THAT'S LIKE TWO MAJOR THINGS THAT PEOPLE WOULD HAVE TO DEAL

WITH.

HOW DO YOU HELP PATIENTS UNDERSTAND THE PROCESS?

>> IT'S OBVIOUSLY, YOU CAN'T TAKE AT THE MOTION OUT OF EITHER

CONDITION.

THERE'S A LOT OF EMOTIONS ASSOCIATED WITH THEM AND PEOPLE

ARE PEOPLE, WE'RE HUMAN BEINGS.

AT THE END OF THE DAY THIS IS LIFE THREATENING ON BOTH ENDS.

IT'S ALL ABOUT ASSESSING RISK, WHAT IS THE MOST RISK NOW, AND

IF THE BREAST CANCER IS THE MOST RISK, WHICH IT USUALLY IS

IMMEDIATELY, THEN YOU MANAGE THE BREAST CANCER, AND YOU MONITOR.

AND YOU MAY, AS I SAID, MAYBE USE LESS AGGRESSIVE THERAPIES.

AND THERE ARE LESS AGGRESSIVE THERAPIES, BUT IT HAS TO BE WITH

THE AGREEMENT OF THE ONCOLOGIST THAT THAT IS AN APPROPRIATE

THERAPY FOR THAT PARTICULAR PATIENT.

For more infomation >> Baystate Medical's Dr. Heba Wassif on Breast Cancer Treatment and Heart Disease | Connecting Point - Duration: 8:25.

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4.8 Semi Centralized Treatment, Treatment Stages - Duration: 5:33.

Unfortunately, around the world, huge amounts of waste water and sludge end up untreated

into rivers, lakes, and into the sea.

What does it take to treat them?

I will now introduce you to the centralized and semi-centralized treatment technologies.

The treatment process can be divided into several stages.

The pre-treatment, the primary treatment, the secondary treatment, the tertiary treatment,

or post-treatment.

Within these categories, some technologies are based on biological

processes: aerobic, anaerobic or both.

And some others on physical, chemical ones.

In this module, we'll have a look at the different treatment stages

and then focus on pre- and post-treatment, which can be implemented in any system.

we will review the anaerobic technologies, The learning goals

of this series of modules on treatment are: get to know the different treatment technologies,

understand the different treatment stages and processes,

and understand the different functions of the treatment technologies.

Let's start.

First, let's review the different treatment stages.

The two main treatment stages are called primary and secondary.

"Primary treatment" consists in the liquid/solid separation.

For example, through sedimentation.

As for the "Secondary treatment", it consists of the removal

of organic matter and suspended solids.

The "pre-treatment" is the preliminary removal of waste water or sludge constituents, such

as oil, grease and various solids, like sand and trash.

Pre-treatment is a must.

On the other hand, the "tertiary treatment" and "post-treatment"

consist of removing elements like remaining pathogens,

nutrients such as nitrogen and phosphorous, or micropollutants from the effluent.

Tertiary treatment embraces a large spectrum of technologies,

and most of them are not implemented in low- and middle-income countries.

Too expensive and too complex.

Let's have a look at a few pre-treatment technologies.

Pre-treatment is a preliminary removal of waste water

or sludge constituents, either before conveyance, or before treatment systems.

It is meant to prevent the accumulation of solids

in further stages and avoid blockages.

It can also help produce abrasion of mechanical parts and extend the life

of sanitation infrastructure.

Pre-treatment technologies use physical removal mechanisms such as screening,

flotation, settling, and filtration.

"Screening" is used, for example, in the screens to prevent trash

and coarse solids to end up in the sewerage system

or the treatment plant.

"Flotation" is used, for example, in grease traps and grids interceptors

to remove the fats, oil and grease.

Finally, "settling" is used, for example, in the sand trap,

or grit chambers, to remove the heavier solids.

As you can see in this figure, grease traps and grit chambers

can be combined in one technology.

On the other end of the treatment process, there are different possibilities to polish

the effluent: the so called post- treatment technologies.

Depending on the design and use of the effluent, or on national standards for discharging water

bodies, a post-treatment step may be required

to remove pathogens, residual suspended solids, or its soil constituents.

This can be mainly achieved through tertiary filtration

and disinfection techniques.

Filtration process can be classified in two categories: first, the depth,

or "packed-bed filtration", as shown in this figure,

where the effluent passes through a filter medium,

such as sand or activated carbon.

On the other hand, "surface filtration" removes undesired elements through sieving;

for example, through membranes.

As for "disinfection", its target is the elimination of pathogenic micro-organisms.

Chlorine is the most widespread technique.

Chlorine is mixed with effluent at the outset of the treatment plant,

as shown in this figure, with a chlorine diffuser and a chlorine mixer.

You can also do disinfection through UV radiation or ozonation,

the two being more energy intensive.

However, you have to be cautious with disinfection.

For example, chlorine together with organic matter

can form toxic byproducts, harmful for the environment.

It should thus only be applied if strictly necessary.

You don't want to create more problems than you actually solve.

To sum up, we saw that treatment is a succession of different steps,

the main ones being the primary and secondary treatment.

Pre-treatment is a must, as a kind of preventive measure,

either at the household level, at the street level,

or at the inlet of a treatment plant.

Post-treatment is not always necessary, and a pragmatic approach is recommended.

The effluent quality should match the intended end use

practice, or the quality of the receiving water body.

For more infomation >> 4.8 Semi Centralized Treatment, Treatment Stages - Duration: 5:33.

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4.6 Collection and Storage Treatment, Anaerobic Technologies - Duration: 7:44.

In this lecture, we are going to look at technologies for on-site blackwater and

greywater management, including the septic tank and the biogas reactor.

These technologies are based on anaerobic processes, and I will just

explain what that means.

The word 'anaerobic' describes biological processes that occur in the

absence of oxygen.

These processes naturally take place in swamps, marshes, ponds and other

standing water bodies.

They can easily be recognized by the formation of gas bubbles, as shown

in these beautiful photographs.

The gas is formed, for example, at the bottom of a pond, where the anaerobic

bacteria decompose carbon-rich organic substances into methane and carbon dioxide

(also called 'biogas').

The gas bubbles then rise to the surface.

In cold areas, where the lake surfaces freeze in wintertime, it can sometimes be

observed that the bubbles get trapped below the ice surface,

as shown on the two pictures on the right side.

In wastewater engineering, we often talk about 'anaerobic digestion.'

The term 'anaerobic digestion' refers to the degradation and stabilization of

organic matter by microorganisms without oxygen, leading to production of biogas.

Both anaerobic and aerobic processes are used for wastewater treatment.

The aerobic ones need aeration systems to provide enough oxygen and are technically

a bit more complex.

They are, therefore, not so commonly used at the collection and storage level.

We will introduce those technologies later in the collectors about centralized and

semi-centralized treatment.

So much for an introduction to the general processes.

Now we want to look at a few technologies.

The septic tank is among the most widespread onsite sanitation technologies.

There are two important things you have to know about the septic tank.

First - it is a water-tight tank, typically made of reinforced concrete,

polyethylene or fiberglass and, second - it has an outlet, through which

the clarified effluent leaves the tank.

In practice, people are not always aware of those two aspects.

They may even call an open-bottom pit a septic tank, which is actually wrong.

Blackwater and greywater enter the tank through an inlet T.

Settleable solids fall down to the bottom, where they accumulate as sludge.

With time, the sludge undergoes some stabilization by anaerobic digestion.

It has to be removed every 3-5 years.

Floatable substances move up to the surface, forming a scum layer.

The effluent from the clearwater zone, in the middle, flows out through an outlet T

and is then typically infiltrated, for example, in a leach field.

One or two separation walls in the tank can improve the solid / liquid

separation process.

The good thing about septic tanks is that they are passive and do not require

electrical energy to function.

This makes this technology quite robust.

Construction is relatively costly but the technology has a long service life

and requires little maintenance.

The costs for mechanical emptying, however, may be considerable.

Little space is required because this technology is typically built underground.

On the negative side - it has to be mentioned that the removal of

pathogenic organisms, suspended matter, organic substances and nutrients is

relatively low, therefore, the effluent, as well as the sludge,

require further treatment and / or appropriate discharge.

To ensure optimum performance of the septic tank, it has to be regularly pumped

as shown in the photo.

An anaerobic baffled reactor, or ABR, is like an improved version of a large

septic tank.

Its functioning is very similar, but it is equipped with baffles,

which form several anaerobic chambers to remove and digest organics and improve

the treatment performance.

The treatment can be further improved by providing 1 to 3

fixed-bed filter units, which helps to trap non-settleable suspended particles

and provide an increased surface for microbial growth.

This technology is called "anaerobic filter."

An ABR, or an anaerobic filter, can be installed at the small scale for on-site

collection and treatment, but also at semi-centralized or centralized

treatment level.

More detailed explanations of these two technologies will be provided in module 3.2.

In the septic tank, ABR (or anaerobic filter), the gases produced in the anaerobic processes

are just released into the atmosphere because their quantities are relatively

low.

The biogas reactor, or anaerobic digestor, however, is designed

to generate as much biogas as possible and to capture and collect it,

so that it can be used as a renewable energy source for cooking or other purposes.

The blackwater from a toilet can be directly connected to the digestor.

In order to produce significant amounts of biogas, additional inputs like cow dung or

organic solid waste, are normally mixed in at the inlet.

The substrate flows into the reactor, where it has a retention time of,

typically, 15-to-25 days.

The biogas collects in the dome at the top of the reactor, and is transported

to the point of use, through a gas pipe.

When new substrate is added to the reactor or when the gas pressure rises, the digestate

flows into the expansion chamber from where it can be removed.

In the photos, you can see some examples of different biogas reactor designs.

Picture on the upper left shows a thick stone reactor under construction.

This is another thick stone digestor, similar to

the one previously shown on the drawing.

As you can see, the space requirement is quite low, because it can be built underground.

On the right side, you can see a floating dome reactor, where the

gas storage can move up and down, depending on the gas volume inside;

and this one here is a biogas stove.

This technology has the clear benefit that no energy is required for operation, but energy

is actually produced.

A high reduction of organic matter and particles can be achieved.

The digestate is almost odorless and still contains all the nutrients, so it

can be used as an excellent fertilizer, however, the agricultural application

has to be done correctly and carefully because the digestate may still contain

some pathogens.

This technology has many benefits but its success depends on correct implementation

by experts, proper operation and regular maintenance.

We have seen that there are several anaerobic technologies that are robust

and easy to operate for on-site treatment of blackwater and greywater.

I want you to remember two things from this module:

First - septic tanks can be a good solution but it is important that the

effluent is properly disposed of and that the sludge is regularly removed.

The second thing that I want you to remember is that the biogas reactor

can be an attractive technology, but the economic benefits do not mean that it is

always automatically successful.

Whether or not the initial investment costs can be recovered will depend on the

correct design and implementation and their motivated operator.