Zagreb, Croatia, June 7 th, 2013. History History : The independent study of the textile technology...

Zagreb, Croatia, June 7th, 2013.


HistoryHistory:

The independent study of the textile technology in Croatia started at the beginning of 1960 as a study at the Faculty of Technology in Zagreb

first only textile chemical engineering, then later mechanical and clothing engineering

and at three independent colleges of textiles in Duga Resa, Varaždin and Zagreb

In 1991 the Institute of Textile and Clothing was organized as an independent Institution named Faculty of Textile Technology of the University of Zagreb


DepartmenDepartmentsts:

Department of Materials, Fibres and Textile Testing

Department of Textile Design and Management

Department of Clothing Technology

Department of Textile and Clothing Design

Department of Fundamental Natural and Engineering Sciences

Department of Textile Chemistry and Ecology

Department of Applied Chemistry

Study in Varaždin

Centre for Development and Transfer of Textile and Clothing

Technologies and Fashion Design


Tihana Dekanic, B.Sc.

e-mail: [email protected]


The Textile industry:

use high volume of water throughout its operation

produce large quantities of wastewaters

is very diverse

broad manufacturing sector

main pollution come from dyeing and finishing processes (require

the input of a wide range of chemicals and dyestuffs – organic

compounds of complex structure)

Major pollutants are:

high suspended solids

heat

colour

acidity or alkalinity

other soluble substances


Classification of fibers:

by TYPE

by LENGTH

by SIZE


Properties:

strengthdurabilityabsorbentcomfortableflexiblegood resistant to alkalispoor acid resistantpoor wrinkle resistance

Features:

soft fibersfiber – single elongated cell – twisted and ribbon like – wide inner hollow (lumen)90% cellulose, 6% moisture, other fats and impurities


Properties:

absorbentlightweightversatilenaturally UV protectiondurable and elasticnon allergenicbiodegradableflame retardanteasy care

Features:

fibre – irregular, roughly cylindrical, multi cellular structurethree basic layers: epidermis (outer layer), cortex (middle layer) and medulla (inner layer)


Properties:

high melting temperaturestronghydrophobicresistant to stretching and shrinkingresistant to most chemicalswrinkle resistantabrasion resistanteasily washed

Features:

smooth, straight, round cross sectionally rod-like shape term „polyester” – mostly refers to polyethylene terephalate (PET)

I. II.

III. IV.

Cotton fibres

before washing

after 11 washing cycles



visible changes of mechanical properties during washing and drying


Water:

water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds

three states of matter: solid liquid gas

covers 71% of the Earth surface (96,5% in oceans, 1,7% in ground water, 1,7% in glaciers and ice caps and 0,001% in the air)

only 2,5% is fresh water and 98,8% of that water is in ice and groundwater

less than 0,3% of all fresh water is in rivers, lakes and the atmosphere


Chemical and physical properties:

is liquid at standard temperature and pressure polar molecule with electrical dipole moment due to non linear structure high surface tension have cappilary action universal solvent low electrical conductivity density thermal: specific heat and latent heat viscosity osmotic pressure optical properties electrical properties: dielectric constant, electrical conductivity


Absolutely pure water is never found in nature!

According to Regulation on Water Classification, there are two groups of indicators of water quality:

1st groups: mandatory indicators (physical and chemical parameters, oxygen demand, microbiological and biological indicators)

2nd groups: metals, organic compounds, radioactivity


1. PHYSICAL INDICATORS:

1.1. Suspended matters

This includes all matter suspended in water that is large enough to be retained on a filter with a given porosity.

1.2. Turbidity

Measures the amount of suspended particles in water

1.3. Colour

The color of a water sample can be reported as:Apparent color is the color of the whole water sample, and consists of color from both dissolved and suspended componentsTrue color is measured after filtering the water sample to remove all suspended materials



1.4. Transparency

Transparency measures how far light can penetrate a body of water.

1.5. Conductivity

Conductivity () is transmission speed of electrical charge through the material (mS/cm).

In water is affected by the presence of inorganic dissolved solids such as chloride, sulfate, sodium, calcium and others.

1.6. Odour and taste

Water odour can cause organic substances. Taste water could be indicators of changes in water sources or treatment process. Inorganic compounds such as magnesium, calcium, sodium, copper, iron, and zinc are generally detected by the taste of water.



1.7. Temperature

Normal temperature: 22°C (limit value of wastewater temperature is 30°C)

Sources: sunlight, thermal pollution

Effects: amount of oxygen that can dissolve, photosynthetic rate, metabolic rates change, senitivity to toxic wastes.

Water temperature fluctuates seasonally, resulting in thermal stratification in deeper water.

Wastewater: commonly higher; vary from season to season and with geographic location

The stratification of a lake in the summer


2. CHEMICAL INDICATORS

2.1. Total dissolved solids

TDS is a measure of the combined content of all organic and inorganic substances contained in a water in: molecular, ionized or micro-granular suspended form

2.2. pH

pH is measure of acidity in water (hydrogen ion concentration)

pH = - log [ H+ ]

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

acid alkalineneutral



2.3. Alkalinity

Alkalinity is the quantitative capacity of water to neutralize an acid. Expressed in mg/l CaCO3. Wastewater is normally alkaline.

2.4. Hardness

Calcium and magnesium salt content Temporary hardness - carbonates and bicarbonates, can be

removed by boilingequilibrium: CaCO3 + CO2 + H2O Ca⇋ 2+ + 2HCO3

−

Permanent hardness - sulfates, chlorides, other anions

Classification of water by German Hardness



2.5. Dissolved gases

Prime importance in considering the quality of water along with the other physical and chemical characteristics.

Important gases dissolved in waters: oxygen carbon dioxide nitrogen ammonia hydrogen sulfide sulfur dioxide chlorine etc.

2.6. Organic matters

Organic matter - organic material present in surface or ground water. Division to: biodegradable and non-biodegradable.Three major sources:

the breakdown of naturally occurring organic materials commercial and domestic chemical wastes chemical reactions that occur during water treatment and filtration

processes



2.7. Nutrients

Nutrients in wastewater: organic carbon nitrogen phosphorus potassium

Required for the primary production of organic matter

2.8. Metals

Most of them are dissolved in water. Can cause public health or aesthetic problems (taste, odour, colour) if not removed.

Can be divided into: non-toxic: arsenic, barium, cadmium, chromium, lead,

mercury, silver toxic: sodium, iron, manganese, aluminum, copper and zinc



2.9. BOD (Biochemical Oxygen Demand)

The amount of oxygen (mg O2/l) required by aerobic microorganisms to decompose the organic matter in a sample of water at 20°C.

Measured after 5, 20 or 100 days (BOD5, BOD20 or BOD100).

2.10. COD (Chemical Oxygen Demand)

The amount of oxygen which is needed for the oxidation of all organic substances (biodegradable and non-biodegradable) in water (mg/l or g/m3).

2.11. TOC (Total Organic Carbon)

To characterize the dissolved and suspended organic matter in water.

2.12. DOC (Dissolved Organic Carbon)

To characterize only organic material that is actually dissolved, not suspended.



2.13. AOX (Adsorbable organic halogens)

The sum of parameters for water soluble "adsorbable organic halogens" in which 'A' stands for adsorbable, 'O' for organic and 'X' for the halogens chlorine, bromine and iodine.

2.14. Other

fluorides (smaller amounts are good in preventing tooth decay) chlorides (give salty taste, can cause corrosion) sulfates (due to the dissolution of minerals can cause indigestion) cyanides (very dangerous, point to pollution waste water) radioactive substances (cause mutagenic changes, sterility,

cancer)


3. BIOLOGICAL INDICATORS:

Biological indicators (bioindicators) are organisms or communities of organisms, which reactions are observed representatively to evaluate a situation, giving clues for the condition of the whole ecosystem.

Measurement:

saprobic index

the degree of biological production

microbiological indicators (coliform bacteria, E-coli, faecal

streptococcus)

the degree of toxicity


3. BIOLOGICAL INDICATORS:

Biological surface water quality determinants being monitored according toWater Classification Act (“National Gazette” , NN 77/98) are:

Saprobic index (Pantle – Buck),Extended Biotic Index and

Trophy status (lakes)

Bioindicator system that is currently in use in Croatia:Wegl (1983)

Analysed communities:Benthic macroinvertebrates

PeriphytonBioseston

HRIS - national bioindicator system (2005)

Surface water quality monitoring in Croatiacontinuous monitoring in Republic of Croatia started in the 1950’water quality monitoring is mainly based on physico-chemical parameters since 2000 water quality assessment is significantly improved sampling and assessment of water quality is done in accordance with Croatian (HRN) or International norms (ISO-EN) in authorized laboratories


Croatia: the quality indicators of industrial wastewater discharged into the public sewage system or into surface watercourses and their limits are prescribed and explained in the Regulation on limit values and other hazardous substances in wastewater

INDICATORS AND MEASURESSURFACE

WATER

PUBLIC SEWER SYSTEM

REFERENCE METHOD OF MEASUREMENT

GENERAL INDICATORS

pH 6,5-9,0 6,5-9,5 HRN ISO 10523:1998

Temperature [ oC] 30 40 DIN 38404-C4

Deposited matters [ml/l] 0,5 10 DIN 38409-H9

Suspended matters [mg/l] 80 (a) HRN ISO 11923:1998

ORGANIC INDICATORS

BOD5 [mgO2/l] 30 - HRN EN 1899-1:2004

COD [mgO2/l ] 200 (e) (d)HRN ISO 6060:2003HRN ISO 15705:2003

TOC [mgC/l] 60 (c) (d) HRN EN 1484:2002

AOX [mg/l] 0,5 0,5 HRN EN 1485:2002

Surfactants, anionic and nononic [mg/l] 1,0 (a) HRN EN 903:2002

Mineral oils [mg/l] 10 20 HRN EN ISO 9377-2:2002

Parameters and Maximum Permissible Concentration

(MPC) for laundry wastewater with applicable

standards


INORGANIC INDICATORS

Sulphides dissolved S [mg/l] 0,5 1,0HRN ISO 10530:1998HRN ISO 13358:1998

Sulphates SO4 [mg/l]

Sulfites SO3 [mg/l]

Free chlorine [mg Cl2/l] 0,2 0,5HRN EN ISO7393-1:2001 HRN EN ISO 7393-2:2001 HRN EN ISO 7393-3:2001

Total chlorine [Cl2mg/l] 0,5 1,0HRN EN ISO 7393-1:2001 HRN EN ISO 7393-2:2001 HRN EN ISO 7393-3:2001

Total phosphorus [mg P/l] 1,0 - HRN ISO 6878

Ammonium [mg N/l] 5HRN ISO 5664:1998HRN ISO 7150-1:1998

Total chromium Cr [mg/l] 1,25 4,0HRN EN 1233HRN ISO 8288

Chromium Cr6+ [mg/l] 0,1 0,2 HRN ISO 11083

Ortophosphates [mg P/l] 1-4 - HRN ISO 6878

Nitrites [mg/l] 0,5-2 10 HRN ISO 10304-2

Nitrates [mg/l] 2-10 - HRN EN ISO 10304-2

AOX [mg/l] 0,1-7,5 1 HRN EN 1485

SURFACTANTS

Total surfactant [mg/l] 4-10 20 Σ surfactants

Anionic surfactant [mg/l] 1-4 10

HRN EN 903ASTM D 4251-89HRN EN ISO 7875-1HRN ISO 2271

Nonionic surfactant [mg/l] 1-4 10HRN ISO 2268HRN ISO 7875-2

Cationic surfactant [mg/l] 0,2-1,0 2HRN EN ISO 2871-1HRN EN ISO 2871-2ASTM 5070-90


The common characteristics of textile wastewater are:

high chemical oxygen demand (COD) high biological oxygen demand (BOD) high temperature high pH solid materials phenol, sulphure and the colours caused by different dyes

Wastewater of textile industry are changeable in amount and composition.

The 1st reason of pollutants: is the natural impurity in fibres.

The 2nd reason: is the chemical materials that are used in processes. A huge amount of dye, carriers, chrome and its derivations

and sulphur are found in wastewater.


Textile industry is a very diverse sector in terms of raw materials, processes, products and equipment and has very complicated industrial chain.

Main pollution came from dyeing and finishing processes. These processes require a wide range of chemicals and dyestuffs, which are generally organic compounds of complex structure.

Because all of them are not contained in the final product, became waste and caused disposal problems.

Besides its complex forms, textile wastewater creates problems due to their high volume. This industry takes place in the first ranks on account of water consumption.

The other problem is that it produces wastewater in different forms and volumes since textile industry has many subdivisions.


Major pollutants in textile wastewaters are high suspended solids, COD, heat, colour, acidity and other soluble substances.

Substances which need to be removed from textile wastewater are mainly COD, BOD, nitrogen, heavy metals and dystuffs.

Process Effluent composition Nature

Sizing starch, waxes, carboxymethil cellulose (CMC), polyvinyl alcohol (PVA), wetting agents

high BOD, COD

Desizing starch, CMC, PVA, fats, waxes, pectinshigh BOD, COD, suspended solids, dissolved solids

Bleachingsodium hypochlorite (NaClO), Cl2, NaOH, H2O2,

acids, surfactants, NaSiO3, sodium phosphate,

short cotton fibre

hihg alkalinity, high suspended solids

Mercerizing sodium hydroxide, cotton waxhigh pH, low BOD, high suspended solids

Dyeing dystuffs, urea, reducing agents, oxidizing agents, acetic acid, detergents, wetting agents

strongly coloured, high BOD, high dissolved solids, low suspended solids, heavy metals

Printing pastes, urea, starches, gums, oils, binders, acids, thickeners, cross-linkers, reducing agents, alkali

highly coloured, high BOD, oily appearance, high suspended solids, slightly alkaline, low BOD

Finishing resins, waxes, chlorinated compounds, acetate, softeners, formaldehyde, PVA

high alkalinity, high acidity, toxicity, high organic and inorganic suspended solids

Leather production

sulphite, chromium, synthetic tannins, biocides, lubricants

toxicity, high organic and inorganic suspended solids, odour

Textile care fats, detergents, chlorine, active oxygenhigh BOD, high COD, high alkality,low suspended solids, toxicity, foam


Washing is a complex process that is occurs in an aqueous meduim with the influence of four parameters:

temperature time mechanics chemistry

All factors are important and need to be optimized in order to achieve a good results of washing.

Particulary is important a hygienic aspects of quality control in the textile laundry from hospital, nursing homes, food and pharmaceutical industries, where is very important disinfection (thermal, chemical or chemo-thermal).

Disinfection effect depends on temperature, concentration of disinfectants, time of action, the presence of microorganisms and the structure of the environment.


Factors that influence on washing effects:

1. WATER

-quantity

-hardness (ratio Ca 2+/Mg2+)

-purity, microbiological composition, content of heavy metals

2. SOILING

-the degree and type of soiling

-interaction with components of detergent-composition and structure of textile materials

3. TEXTILES

- textiles (fabric, yarn..)- sweling Tg

- finishing, coloration

- charge (dimenzion, size..)

- purpose, residues


4. WASHING MACHINE

washing temperature (initial, heating, final temperature)

washing time

mechanics of laundering (rotation speed, reversible rotation and drum diameter), volume, volume baths, weight and dimensions of textiles, fabrics/friction, foam), washing program (prewash, main wash and rinse)

5. DETERGENT

Active components

anionic surfactant

nonionic surfactant

soap

cationic surfactant

Inorganic components

alkalies (silikates, Na2CO3)

phosphates (sodium triphosphate)

zeolites (sodium aluminosilicate)

chemical bleaches (sodium perborate, sodium percarbonate)

stabilizer (magnesium silicate)


Organic components

cobuilders (NTA, citrates…)

polycarboxylic acid polymers

optical brigheteners

solvents (alcohols)

enzymes (protease, amylase, lipase, cellulase, mananaze)

activators of chemical bleaches (EDTA and NOBS)

graying inhibitors (carboxymethyl cellulose, hydroxyethyl cellulose, special polymers (SRP), fragrance)

Generally:

laundering is an energy intensive process more than 90% of energy for washing is used to heat the water - thus low temperature washing should be a great energy saver however an important factor to consider is that reducing the washing temperature decreases the degree of disinfection and increases the possibility of cross-infection of textiles washed in the same load


preparation of technological water (ion exchangers: synthetic resins and ion exchange)

REQUIREMENTS

Water hardness (°dH) 0

Iron content (mg/l) 0,1

Copper content (mg/l) 0,05

Manganese content (mg/l) 0,03

The total number of microorganisms (CFU/ml) Water-rinse

100

Prewash

1000

ANALYSIS AFTER RINSING

organic incrustation(%) 1

inorganic incrustation(%) 1

pH 6,5-8,3

Anionic surfactant (g/g) 200

Nonionic surfactant (g/g) 400


Wastewater due to the pollution source

NORMAL LAUNDRY

HOSPITAL LAUNDRY

WORKING CLOTHES

CLEANING CLOTHES

COD (mg O2/l) 600 - 2500 400 - 1200 1200 - 20000 to 100000

hydrocarbons (mg/l) 0 - 10 - 0 - 20000 to 30000

Surfactant (mg/l) 30 - 150 20 - 120 100 - 600 to 300

AOX (mg/l) 0 - 4 0 - 12 0-36 to 50

Copper (mg/l) 0 - 0,4 0 - 0,2 1-7 to 100

Lead (mg/l) 0 - 0,2 0 - 0,1 0,7-2,8 to 100

An important criteria at industrial laundry are hygienic conditions, especially in the case of hospital laundry and laundry from food industry.

It is referring to the disinfection of all work areas, vehicles, auxiliary devices (transport truck), employees and equipment.


When wastewater (effluent) discharged into a river body such as lake, river or sea, a number of process occur which cause loss of organisms

It is necessary to treat effluent or waste before discharging in water body

The types of water treatment are regularly used to: improve water quality remove microorganisms reduce the level of toxic substances

The treatment procedure are generally divided into three groups: PRIMARY TREATMENT (mechanical treatment) SECONDARY TREATMENT (biological treatment) TERTIARY TREATMENT (advanced biological or chemical treatment)


PRIMARY TREATMENT - mechanical treatment

suspended solids and floating material is removed physical and/or chemical treatment

Sedimentation:

the suspended and colloidal impurities are separated in sedimentation tank by gravitation

the main principle: allow water to rest or flow at a very slow velocity - heavier particles settle down due to gravity

settling of particles depend on velocity of flow, size, shape and specific gravity of particles and viscosity of liquid

the velocity of water decreased by increasing the length of flow


Major differences in aerobic and anaerobic treatment

Parameter Aerobic treatment Anaerobic Treatment

Process principle

microbial reactions take place in the presence of molecular/free oxygenreactions product are carbon dioxide, water and excess biomass

microbial reactions take place in the absence of molecular/free oxygenreactions products are carbon dioxide, methane and excess biomass

Applications

Wastewater with low to medium organic impurities (COD<1000 ppm) and for wastewater that are difficult to biodegradable e.g. municipial sewage, refinery wastewater etc.

Wastewater with medium to high organic impurities (COD>1000 ppm) and easily biodegradable wastewater e.g. from food and baverage wastewater rich in starch/sugar/alcohol

Reaction kinetics Relatively fast Relatively slow

Net sludge yield Relatively highRelatively low (generally one fifth to one tenth of aerobic treatment process)

Post treatmentTypically direct discharge or filtration/ disinfection

Invariably followed by aerobic treatment

Foot-Print Relatively large Relatively small and compact

Capital investment Relatively high Relatively low with pay back

Example technologiesActivated sludge e.g. etended aeration, MBR, fixed film processes etc.

Continuously stirred tank reactor/digester, upflow anaerobic sludge blanket etc.


Aerobic Activated sludge process

most versatile biological oxidation process treatment of waste water contain dissolved solid, collides, rough solid

and organic matter sewage from sedimentation tank enter into aeration tank active sludge is mixed for about 4 to 8 hours the microorganisms oxidize organic matter in the presence of abundant

quantity of oxygen in the aeration tank sewage is settle in secondary sedimentation tank some portion of activated sludge is recalculated into the aeration tank contain a large number of aerobic bacteria and other microorganisms


Aerobic Trickling filters (TF) - biotowers

are used to remove organic matter from wastewater an aerobic treatment system enable organic material in the wastewater to be adsorbed by a

population of microorganisms (aerobic, anaerobic, and facultative bacteria; fungi; algae; and protozoa) attached to the medium as a biological film or slime layer

the wastewater flows over the medium - microorganisms form a film - the organic material is degraded by the aerobic microorganisms in the outer part of the layer

layer thickens through microbial growth - oxygen cannot penetrate the medium face - anaerobic organisms develop - biological film continues to grow - microorganisms near the

sloughed solids are picked up and transported to a clarifier for removal from the wastewater

surface lose their ability to cling to the medium - a portion of the slime layer falls off the filter (so-called sloughing)


Aerobic Advantages and disadvantages of Trickling filters (biotowers)


AerobicAerated pond - lagoon

wastewater is purified by action of algae and aerobic bacteria organic matter are decomposed by bacteria and are consumed by algae oxygen is released during the process of photosynthesis

aerobic bacteria get O2 from atmosphere and convert the organic matter present in CO2 which is again taken by algae during the process of photosynthesis


biological agents are used to remove the contaminant from water in the absence of oxygen

biological agents include microorganisms which break down biodegradable material present in sludge after it is filtered from polluted water (so-called anaerobic digestion)

huge sealed tanks

Anaerobic treatment

microorganisms breakdown the sludge and convert it to organic acids, carbon dioxide, hydrogen and ammonia

in the later stages the sludge remains are converted to biogas by methanogen

biological anaerobic treatment is a very low energy process

ideal for treating wastewater which is high in soluble BOD and/or COD


Bioremediation

process that uses microorganisms, fungi, green plants or their enzymes to return the natural environment altered by contaminants to its original condition

types of bioremediation: In situ – at the site Ex situ – away from the site

advantages: low cost minimal site disruption simultaneous treatment of contaminated water and soil minimal exposure of public and site personnel

disadvantages: time consuming seasonal variation problematic addition of additives


TERTIARY TREATMENT - advanced biological or chemical treatment

to decrease the content of nitrogen and phosphorous compound in the effluent

Disinfection

Water is disinfected to kill any pathogens which pass through the filters and to provide a residual dose of disinfectant to kill or inactivate potentially harmful microorganisms in the storage and distribution systems

Chlorine disinfection

the most common disinfection method chlorine – a strong oxidant - rapidly kills many harmful microorganisms danger of a release toxic gases - problem is avoided by the use of sodium hypochlorite


Chlorine dioxide disinfection

a faster acting disinfectant than elemental chlorine chlorine dioxide is supplied as an aqueous solution and added to water to avoid gas handling problems

a powerful disinfectant, excellent for removing odours, destroys organic matter, viruses and spores

very explosive so cannot be stored

Advanced Oxidation Processes (AOPs)

the aim of these methods is to mineralize the pollutants, i.e., to convert them entirely to CO2, H2O, and mineral acids such as HCl

most AOPs are ambient-temperature processes

generation of significant amounts of the hydroxyl free radical (OH.) – in aqueous solution is a very effective oxidizing agent the hydroxyl radical can initiate the oxidation of a molecule – by extraction of hydrogen atom, or addition to one atom of a multiple bond, or extract an electron from an anion


Fenton process

based on oxidation by Fenton regaens, which is an oxidative mixture of hydrogen peroxide and Fe2+ ions

effectiveness depends on the pH, temperature and the ratio of the amount of Fe2 + ions and hydrogen peroxide

Advantages: no formation of chlorinated organic by-products, both reactants are relatively inexpensive, simple to use and non-toxic

From AOPs the most common are:

Fenton process

Ozone oxidation

Oxidation by UV rays


Ozone oxidation

Ozone: strong oxidizing agent, unstable to store (has to be made as it isused)it is produced by passing an electrical discharge through air which is then bubbled through the water powerful oxidizing agent which is toxic to most waterborne organisms some of the advantages include the production of fewer dangerous by-products (in comparison to chlorination) and the lack of taste and odour produced by ozonisation

Oxidation by UV rays

very effective at inactivating cysts

UV lights disinfection effectiveness decreases as turbidity increases

the water is passed through banks of cylindrical,quartz-jacketed fluorescent bulbs disadvantages: some dissolved materials (iron and some organic compounds) can absorb the light, expensive


Other water purification – MEMBRANE PROCESS

Common membrane processes include: microfiltration (MF) ultrafiltration (UF) nanofiltration reverse osmosis (RO)

Water can be purified of most contaminant ions, molecules, and small particles, including viruses and bacteria, by passing it through a membrane in which the individual holes, called pores, are of uniform and microscopic size

the pore size of the membrane must be smaller than the contaminant size


membrane separation processes can be define as procedures which divide the input current (feed liquid) into two streams:

permeate (the part of the input current who is passed through the membrane) retentate (concentrate) part of the input current retained by membrane

REVERSE OSMOSIS or HYPERFILTRATION

water is forced under high pressure to pass through the pores in a semipermeable membrane, composed of an organic polymeric material such as cellulose acetate or triacetate or a polyamide

only water (and other molecules of its small size) can pass through the pores, the liquid on the other side of the membrane is purified water


MEMBRANE BIOREACTOR - MBR

Is an improvement of the conventional activated sludge processes, where the traditional secondary clarifier is replaced by a membrane unit for the separation of treated water from the mixed solution in the bioreactor

Membrane Bioreactor (MBR) Technology is based on Biological Treatment followed by membrane separation.

Advantage:

the high-quality of the purified water increased volume efficiency stops the pathogenic microorganisms and other pollutants enables the growth nitrifying bacteria ability to work on high-organic pollution biomass growth is significantly reduced

Disadvantage:

membrane fouling


TYPES / MODULES of membranes:

plate-and-frame

tubular

spiral-wound

hollow-fiber


prior to discharge of industrial water into the drainage system they need to be purified

method of treatment depends on the technological process where are produces wastewater

the newest and the best effects of water purification achieved by a combination of purification processes

modified the process with the task of reducing the quantity of wastewater

re-use of purified wastewater


Sources of pollution:

from the raw water (salts)

detergents (surfactants – tenzides; phosphates, silicates)

dirt from clothes (fiber clothing, colour, fat, oil)

temperature

Important: physical treatment (membrane procesess)

biological treatment

combination of procesess

Regarding to laundry:

Zagreb, Croatia, June 7 th, 2013. History History : The independent study of the textile technology...

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Transcript of Zagreb, Croatia, June 7 th, 2013. History History : The independent study of the textile technology...