Subscribe For Newsletters: Click Here
1 2 3 4 5 6 7 8 9 10 11 12
Medical Waste Management
 

Healthcare Waste Management System (HCWM)

Healthcare waste is defined as the waste that is generated during the diagnosis, treatment or immunisation of human beings. It constitutes syringes, needles, ampoules, organs and body parts, placenta, dressings, disposables plastics and microbiological wastes.

The management of hospital waste poses to be a major problem in most of the countries, especially developing countries. In recent years, medical waste disposal has posed even more difficulties with the growing volume and increasing types of waste materials.

Hospital wastes are categorised according to their weight, density and constituents. The World Health Organisation (WHO) has classified medical waste into different categories. These are:

  • Infectious: Material-containing pathogens in sufficient concentrations or quantities that, if exposed, can cause diseases. This includes waste from surgery and autopsies on patients with infectious diseases.
  • Sharps: Disposable needles, syringes, saws, blades, broken glasses, nails or any other item that could cause a cut.
  • Pathological: Tissues, organs, body parts, human flesh, fetuses, blood and body fluids.
  • Pharmaceuticals: Drugs and chemicals that are returned from wards, spilled, outdated, contaminated, or are no longer required.
  • Radioactive: Solids, liquids and gaseous waste contaminated with radioactive substances used in diagnosis and treatment of diseases like toxic goiter; and
  • Others: waste from the offices, kitchens, rooms, including bed linen, utensils, paper, etc.

 

Healthcare Waste is hazardous and harmful for human being and environment. It directly affects the people working at healthcare facilities and pollute the environment. It is very important to properly dispose the HCW through a proper system. Government of Nepal has issues the guidelines to dispose the HCW.

Followings are the main steps of HCWM :
  • Waste Minimization
  • Waste Seggregation & Collection
  • Waste Storage & Transportation/Handling
  • Waste Treatment and Disposal
  • Training to Healthcare workers for HCWM.
TAS specializes in HCWM System and provide a complete solution right from tips on waste minimization to Waste segregation to disposal and training.
 

A. Waste Minimization

Waste Minimization can be done by using biodegradable materials and consumables as far as possible. Not using potentially hazardous materials like mercury thermometers and Blood Pressure Monitoring machines etc.
 

B. Waste Segregation & Collection

Segregation means the separation of the entire waste generated in a hospital in defined, different waste groups according to the specific treatment and disposal requirements. Only a segregation system can ensure that the waste will be treated according to the hazards of the waste and that the correct disposal routes are taken and that the correct transportation equipment will be used.

Segregation is the key to any effective waste management !

You can use following materials for Hospital Waste Segregation & Collection:

B1. Sharp Waste

Needles, Needle and Syringe assemblies, Lancets, Scalpets, Blades, Scissors, Sutures, Specimen, Tables, Broken Glass, Ampoules, Intravenous Catheter, Glass Slides, Cover Slips.

Sharp Waste can disposed in followings ways :

Sharp Containers
Our range of Sharps Containers are used for the disposal of sharp and cutting waste. They are puncture resistant and come in several shapes and sizes to facilitate use at different sites of the hospital. Colour of Bins : Red

Needle cum Syringe Destroyer
It destroys the syringe & needle both in single action. Having stainless steel body having facility for table & wall mounting. Bio-degradable & autoclavable material having 3Ltrs capacity. It cuts hub & needle fall in sharp container. 

Consumables : Sharp Containers
Colour of Syringe Destroyer : Yellow

B2. Hazardous/Clinical Waste

Gloves, Gowns & Masks, Gauze, Dressings & Swabs, Spatulas, Urine & Blood Bags, Sump tubes & Suction Canisters, Disposable bowls & Containers, Hemodialysis tubings, Intravenous lines, Bags, Foley's catheters & Sanitary napkins

Hazardous & Clinical Waste can be disposed either in a disposable biodegradable containers or reusable containers using biodegradable bags.

Disposable Containers
Disposable containers are made of biodegradable plastic, in which the hazardous waste can be collected and it can be disposed after it is filled-up.
Colour of Bins : Yellow
Reusable Containers Reusable Containers known as CLIPPERS are reusable plastic bins (autoclavable) in which waste can be collected using biodegradable plastic bags/linings. Colour : Yellow

B3. General Waste

Packages boxes, Wrappings, Newspapers& Magazines, Disposable plates, Cups & Utensils, Food, Food packaging, Packages boxes, Wrappings, Newspapers& Magazines, Disposable plates, Cups & Utensils, Food, Food packaging.

Reusable Containers known as CLIPPERS are reusable plastic bins (autoclavable) in which waste can be collected using biodegradable plastic bags/linings. Colour : Grey/Green


C. Waste Storage and Transportation/Handling

Storing and transporting the healthcare waste is very important to avoid the spread of infection while storing or transporting. Special containers and specially designed transport system is used for the same.

D.Waste Treatment & Disposal

Waste Treatment and Disposal is one of the most important part of HCWM System. Following different methods can be used for the same.

D1. Sterilizers & Shredders

Sterilizers : The waste is sterilized by autoclaving using steam at high pressure and temperature (134ºC). This ensures that the biologically harmful elements of the waste are destroyed.
Shredders : Shredding ensures that any sharp elements of the waste are broken down, making them safe for handling and disposal. Another advantage of shredding is that it reduces the treated waste’s volume.

Integrated Sterilizer & Shredder :

The ISS performs both shredding and waste steam sterilization in a single vessel. The vessel is fitted with a motordriven shaft, with powerful shredding/crushing blades which reduce the size and volume of the waste.

image
  • Easy to Operate – No need for special technician qualification.
  • Environmentally Sound - Shredded waste is reduced to as little as 1/5 its original volume, without emitting harmful substances.
  • Cost-effective - Inexpensive operation and maintenance.
  • Totally Safe - Automatic locking door prohibits unauthorized interruption.
  • Efficient - A single unit can serve any middle size hospital, clinic or laboratory.
  • Compact - Room of only 3 x 4 meters is necessary.
  • Easily and quickly installed – Within one day.

Celitron’s compact medical hazardous waste solution, the Integrated Sterilizer & Shredder, is a large steam sterilizer with an integrated shredder, designed for on-site conversion of biohazard waste in hospitals and clinics, complying the EU and WHO recommendations.

The stainless steel vessel is fitted with a motor-driven shaft, with powerful shredding / crushing blades that can rotate in two directions to reduce the size and volume of the waste down to 20%.The 5,5kW motor is sufficient to rotate the shaft with an RPM of 300-1100 for various operations. The blades are mounted on the shaft and are designed to shred waste such as sharps, dialyzers, syringes, papers, cloth, plastic and glass. Shredding is important as it enhances the steam penetration therefore improves the overall sterilization results.

The steam is internally produced by a steam generator, supplied by water purification and draining system as standard accessory. The vessel is constructed with internal sprinklers for automatic cleaning. The entire process is automatic, including the opening and closing the door, turning and rotating of the vessel and the sequences of shredding and sterilization. The total cycle time can take as fast as 25 minutes and between 15 to 25 kg of waste can be processed.

After treated in the ISS, the waste is sterile. The liquid components of the waste are steamed out of the vessel, re-condensed and drained to a municipal sewer. As the waste is dehydrated, there is no risk of contaminated waste water. The waste is rendered, fragmented, non-toxic, largely solid and dry and therefore safe to be disposed as regular municipal waste.

D2. Incinerator

Incinerators are the equipment to burn the HCW into ashes. HCW in Sharp Bins, Hazardous waste containers or biodegradable bags can directly be fed into incinerators to burn it into ashes.

The PG/PY - VS series of incinerators function under a combination of controlled heat and air.

The three “T”s of combustion viz. turbulence through air and temperature are controlled in such a way that the waste is first volatilized / gasified under the conditions of inadequate air and temperature and then totally destroyed under conditions of adequate air and right temperature. The third “T”, i.e. necessary residence time in the secondary chamber is provided to achieve complete combustion and thus total incineration.

Thus the waste is incinerated in two stages i.e. the primary chamber and the secondary combustion chamber which are positioned adjacent to each other . The flue gases then pass through the high pressure drop venturi scrubber , droplet separator and are let out to atmosphere via ID fan and chimney. The primary combustion chamber operates under near pyrolytic condition wherein the wastes are decomposed & all volatiles are released. The substrate remaining, gets converted into sterile ash. The volatiles released from primary combustion chamber are then completely burnt in the secondary combustion chamber under high temperature & excess air.


DESIGN :

The Incinerator consists of :

A) PRIMARY CHAMBER :

The primary chamber is lined with refractory and insulation bricks of IS-8 and IS-2042 standards. The air required for volatilization is supplied through an air duct and introduced through equally placed nozzles. Air flow is controlled with the help of air dampers provided. The primary chamber is fitted with a fuel oil burner which has necessary instrumentation to function automatically. A forced draft fan is used to provide for combustion / volatilization air. The combustion air is controlled to have minimum turbulence, restricting ash fly off

The waste is fed through a charging door / DFDV and the ash is removed from the deashing door.

B) SECONDARY CHAMBER :

The volatiles / gases emitted from the Primary chamber pass through the neck to the secondary chamber which is also lined with refractory and insulation bricks / castables .

Just before the flue gas enters the Secondary the combustion air as per stoichiometric condition is mixed .

The vapours are subjected to the right temperature / heat which is generated using an automatic fuel oil burner system. The secondary chamber is designed to ensure the flue gas residence time of one second.

The waste destroyed in the Pyrolytic has the following composition :
1) Volatile Matter.
2) Fixed Carbon.
3) Moisture.
4) Ash or Non Combustibles.

The volatile matter has a low flash point and hence gets liberated in the primary combustion chamber. This is later burnt in the secondary combustion chamber. Volatiles give rise to smell and smoke. These hence have to be burnt, at a high temperature & in the presence of excess air in the secondary chamber. Volatiles are basically long chain hydrocarbons.

Fixed Carbon is the non-volatile portion of the waste and is completely incinerated in primary chamber only.

The Moisture present in the waste is evaporated in the primary chamber This then passes through the secondary chamber and leaves the system as super heated water vapour.

Sterile ash and non-combustible material remain in the primary chamber. To prevent them from flying out along with the gases, non turbulent conditions are maintained in the primary chamber.

Depending upon the type of waste destroyed in the incinerator the sterile ash contain ranges between 5-10 %. At the end of the burning operation we guarantee a similar quantity of sterile ash remaining as left over, proving that the destruction of the waste is complete.

The flue gases then pass through the downstream Air Pollution Control system. This system is designed to remove acidic pollutants and particulate matter present in the flue gases from incineration. This system comprises venturi scrubber, droplet separator followed by , ID fan and stack.

The flue gases from the incinerator are cooled to 850 Deg.C. and then sent to venturi scrubber. Venturi scrubber is a high energy device where (sub micronic) particulate matter as well as acidic pollutants are scrubbed. Here, the acidic gases are removed by absorption with caustic and the particulate by the inertial impaction energy. A high pressure drop (30 – 35 cm Wc) across the venturi scrubber, imparts sufficiently high energy which helps in atomizing the scrubbing liquid and thus trapping the particulate. In venturi, gases saturate due to evaporation of water vapour and thus cools. 5% caustic solution is used as scrubbing liquid to neutralize the SO2 etc. present in flue gases.

The flue gases then enter tangentially into the droplet separator, which is of cyclonic type. By the action of centrifugal force, the larger droplets present in flue gases settles d

own. This helps in protecting the impeller of the ID fan. The ID fan maintains the balance draft and draws out the clean gases into the atmosphere through a 30m high stack.


Portable Incinerators :

Small Portable Incinerators both electrical and diesel operated are available for small clinics and nursing homes. These portable incinerators are also used for burning human parts and tissues, when you have sterilizers for other type of wastes.

image