The Operating Principles of Equipments and Machines

Session 8: The Operating Principles of Equipments and

Machines

Total Session Time: 120 minutes

Prerequisites

Learning Tasks

By the end of this session students are expected to be able to:

Machine, Distiller, Autoclave, De-ionizer etc.)

Resources Needed:

SESSION OVERVIEW

Activity/

Step Time Content

Method

1 05 minutes Presentation Introduction, Learning Tasks

10 minutes Presentation Equipment Used in Facility Based

2

Buzzing Pharmaceutical Preparation Unit

25 Minutes Presentation Operating Principles of an Autoclave

3

30minutes Operating Principles of a Reverse Osmosis

4 Presentation

Machine

20 minutes Presentation

5 Operating Principles of a De-ionizer

20 minutes Presentation

6 Operating Principles of a Distiller

7 05 minutes Presentation Key points

8 05 minutes Presentation Evaluation

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

SESSION CONTENTS

STEP 1: Presentation of Session Title and Learning Tasks (5 minutes)

READ or ASK students to read the learning objectives and clarify

ASK students if they have any questions before continuing.

STEP 2: Equipment Used in Facility Based Pharmaceutical Preparation

Unit(10 minutes)

Activity: Buzzing (5minutes)

ASK students to pair up and buzz on the following questions for 5 minutes

ALLOW few pairs to respond and let other pairs add on points not mentioned

WRITE their response on the flip chart/board

CLARIFY and SUMMARIZE by using the content below

The equipment used in facility based pharmaceutical preparation unit include the following:

STEP 3: Operating Principles of an Autoclave (25 minutes)

dependable procedure for the destruction of all forms of microbial life.

sterilization of your materials.

(autoclaves) for the decontamination of cultures and other materials, for preparing

sterile supplies, and for the safe operation of the autoclave.

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

Figure 8:1 Autoclave machine

Source: KSP IV Production Mannual

o The basics: Why is an autoclave such an effective sterilizer? An autoclave is a large

pressure cooker; it operates by using steam under pressure as the sterilizing agent.

 High pressures enable steam to reach high temperatures, thus increasing its heat

content and killing power.

 Most of the heating power of steam comes from its latent heat of vaporization.

This is the amount of heat required to convert boiling water to steam.

 This amount of heat is large compared to that required to make water hot. For

example, it takes 80 calories to make 1 liter of water boil, but 540 calories to

convert that boiling water to steam.

 Therefore, steam at 100º C has almost seven times more heat than boiling water.

Steam is able to penetrate objects with cooler temperatures.

o How does killing occur? Moist heat is thought to kill microorganisms by causing

coagulation of essential proteins.

 Another way to explain this is that when heat is used as a sterilizing agent, the

vibratory motion of every molecule of a microorganism is increased to levels that

induce the cleavage of intra-molecular hydrogen bonds between proteins.

 Death is therefore caused by an accumulation of irreversible damage to all

metabolic functions of the organism.

 Death rate is directly proportional to the concentration of microorganisms at any

given time. The time required to kill a known population of microorganisms in a

specific suspension at a particular temperature is referred to as thermal death time

(TDT).

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

 All autoclaves operate on a time/temperature relationship; increasing the

temperature decreases TDT, and lowering the temperature increases TDT.

o What is the standard temperature and pressure of an autoclave? Processes conducted

at high temperatures for short time periods are preferred over lower temperatures for

longer times. Some standard temperatures/pressures employed are 115 °C/10 p.s.i.,

 Please note that after loading and starting the autoclave, the processing time is

measured after the autoclave reaches normal operating conditions of 121°C

(250°F) and 15 psi pressure, NOT simply from the time you push on the bottom.

o Time is critical. As the cycle time will vary with the composition of the load, it is

important to determine the appropriate time requirement. Some (ignorant) people

assuming that a time of 30 minutes is sufficient, however this often proves to be a

very costly mistake.

o Volume. Obviously, the higher the volume, the more time is needed for sterilization

(see general guidelines below). Generally, the volume of liquid per container is a

more important consideration than the total volume. A 2-liter flask containing 1-liter

of liquid.

o Microbial load. Contaminated items take longer to sterilize than clean items.

Consequently, water sterilizes faster than yeast-extract containing media (which

contains lots of microbes), or media left at room temperature for a while before

autoclaving (which allows the concentration of microbes to increase). Also, some

types of microbes are more resistant to autoclaving than others.

o Some general guidelines. Here are some recommended times for autoclaving liquids

of the following volume per container:

 Remember to modify these times as needed!!!!! For example, more time is

required if the flasks in a plastic tray (which is the standard method); if many

bottles are close to each other in the tray; if the chamber is full of several trays; if

the liquid contains microbes; if you are using plastic instead of glass containers;

etc. Therefore, you probably need to go longer than the times indicated above

STEP 4: Operating Principles of a Reverse Osmosis Machine

(30minutes)

from water by pushing the water under pressure through a semi-permeable membrane.

pushing it under pressure through a semi permeable reverse osmosis membrane.

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

solution.

with a higher concentration.

pass but not others.

need to apply energy to the more saline solution.

water molecules but not the majority of dissolved salts, organics, bacteria and pyrogens.

applying pressure that is greater than the naturally occurring osmotic pressure in order to

desalinate (demineralise or deionise) water in the process, allowing pure water to pass

through while holding back a majority of contaminants.

through the semi-permeable membrane and the contaminants are not allowed to pass

through.

Figure 8: 2 Reverse Osmosis Machine

Source: KSP IV Production Manual

o Reverse osmosis machine works by using a high pressure pump to increase the

pressure on the salt side of the reverse osmosis and force the water across the semi-

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

permeable reverse osmosis membrane, leaving almost all (around 95% to 99%) of

dissolved salts behind in the reject stream.

o The amount of pressure required depends on the salt concentration of the feed

water.

o The more concentrated the feed water, the more pressure is required to overcome

the osmotic pressure.

o In very simple terms, feed water is pumped into a Reverse Osmosis system and you

end up with two types of water coming out of the reverse osmosis system: namely

good water and bad water.

o The good water that comes out of a reverse osmosis system has the majority of

contaminants removed and is called permeate water.

o Another term for permeate water is product water.

o Permeate is the water that was pushed through the RO membrane and contains very

little contaminants

o The bad water is the one that contains all of the contaminants that were unable to

pass through the reverse osmosis membrane and is known as the concentrate,

reject, or brine water. (all the three terms are used interchangeable and mean the

same thing)

As the feed water enters the reverse osmosis membrane under pressure the water

molecules pass through the semi permeable membrane and the salts and other

contaminants are not allowed to pass and are discharged through the concentrate stream,

which goes to drain or can be fed back into the feed water supply in some

circumstances to be recycled through the reverse osmosis system to save water.

o It is important to understand that reverse osmosis system employs cross filtration

rather than standard filtration where the contaminants are collected within the filter

media. With cross filtration, the solution passes through the filter, or crosses the filter,

with two outlets: under cross filtration, the filtered water goes one way and the

contaminated water goes a different route.

o To avoid build up of contaminants, cross flow filtration allows water to sweep away

contaminant build up and also allow enough turbulence to keep the membrane surface

clean.

o Reverse Osmosis is capable of removing up to 99%+ of the dissolved salts (ions),

particles, colloids, organics, bacteria and pyrogens from the feed water (although an

RO system should not be relied upon to remove 100% of bacteria and viruses).

o A Reverse osmosis membrane rejects contaminants based on their size and charge.

o Any contaminant that has a molecular weight greater than 200 is likely to be

rejected by a properly running reverse osmosis system.

o Because an reverse osmosis system does not remove gases, the permeate water can

have a slightly lower than normal pH level depending on CO2 levels in the feed

water as the CO2 is converted to carbonic acid due to CO2 are not highly ionized

(charged) while in solution and have very low molecular weght.

o In order to accurately measure the performance of an RO system you need the

following operation parameters at a minimum:

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

 Feed pressure

 Permeate pressure

 Concentrate pressure

 Feed conductivity

 Permeate conductivity

 Feed flow

 Permeate flow

 Temperature

o Proper pre-treatment using both mechanical and chemical treatments is critical for

an RO system to prevent fouling, scaling and costly premature reverse osmosis

membrane failure and frequent cleaning requirements.

o Fouling occurs when contaminants accumulate on the membrane surface effectively

plugging the membrane.

o Fouling can be caused by the following

 Particulate or colloidal matter e.g. Dirt, silt, clay etc.

 Organic compounds.

 Microorganism.

o Scaling. As certain dissolved (inorganic) compounds become more concentrated,

then scaling can occur if these compounds exceed their solubility limits and

precipitate on the membrane surface as scale. an example of common scale that

tends to form on reverse osmosis membrane is calcium carbonate .

o Mechanical Damage: If there is too much back pressure on the reverse osmosis

system then mechanical damage to the reverse osmosis membranes can also occur.

STEP 5: Operating Principles of a De-ionizer (20 minutes)

from a solution using an ion exchange process they are also known as ion exchangers or

demineralizers.

ion and anion resin in a single vessel, or "dual bed", where each resin type is in a separate

vessel. Mixed bed deionizers produce water containing the lowest ionic concentrations.

medical purposes such as hemodialysis.

Figure 8: 3 De – ionizer machine

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

Source: KSP IV Production Mannual

o Deionizers remove both cat ions and anions, releasing hydrogen ions (H+) in

exchange for the former, and hydroxyl ions (OH-) for the latter.

o The hydrogen and hydroxyl ions subsequently combine to form pure water.

Figure 8:3:1 Schematic representation of ion Exchange showing exchange of sodium and

Chloride for hydrogen ion and hydroxyl ions. The latter combine to form water

Source: Google (2014).

remove bacteria, endotoxins or pyrogens.

providing an environment which is conducive to bacterial proliferation.

removes bacteria and/or endotoxins, such as ultra filtration, submicron filtration, steam

distillation or even ultraviolet irradiation.

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

STEP 6: Operating Principles of a Distiller (20 minutes)

organisms from water. A clean, well-maintained distiller will remove over 95 per cent of

the minerals, including sodium, sulfate, nitrate and arsenic. Biological contaminants such

as bacteria, viruses and cysts are destroyed during distillation. Water distillers can be

simple, versatile drinking water treatment devices.

cooking which is due to the cost of operation and slow rate of treated water production.

more suitable.

o An electric heating element (1,000 to 1,500 watts) boils water in a stainless steel tank.

o The resulting steam leaves the tank and enters a stainless steel cooling coil.

o In the cooling coil, the steam condenses to form distilled water.

o Some distillers use air to cool the steam.

o Others use incoming water for cooling.

When most of the water is boiled out of the distiller, a float switch turns off the power

to the heating element.

o The concentrated mineral solution left in the boiling tank is drained off, and the

boiling chamber is refilled manually or automatically. Some distillers are built as

portable countertop units. These are usually refilled manually and plugged into

normal 120 volt power outlets. Countertops units normally batch distill 3 to 4 litres of

water at a time.

Other distillers are permanently installed, usually in the house basement.

o They are plumbed into a water supply line, distilled water is collected in a storage

container, and then a small pump is used to pump water to treated water taps,

humidifiers, or fridges and icemakers.

o These units are normally continuous flow type distillers.

Figure 8: 4 distiller operation air cool type

Source 🙁 n.d).Retrieved from

https://www.gooogle.com/search (2018).

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

STEP 7: Key Points (5 minutes)

Osmosis Machine, Distiller, Autoclave, De-ionizer etc.

sterilizing agent.

permeable membrane.

or pyrogens.

organisms from water.

STEP 8: Evaluation (5 minutes)

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

References

“Reverse Osmosis.” Egyptian Journal of Medical Human Genetics, Elsevier,

www.sciencedirect.com/topics/chemistry/reverse-osmosis.

Editorial Board. (2016). Egyptian Journal of Medical Human Genetics,17(4), Iii.

doi:10.1016/s1110-8630(16)30059-3

procedures for autoclave

Pearce G., (2007),The case of UF/MF pretreatment to RO in seawater applications,

Desalination 203 , 286-295 Pilat B.,(2001), Practice of water desalination by

electrodialysis, Desalination 139 . 385-392

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PST 05207 Quality Assurance of Pharmaceutical Products NTA Level 5 Semester 2

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