Chemical Cleaning/Remediation/Decontamination/Decommissioning

Chemical Cleaning/Remediation/Decontamination/Decommissioning

Chemical cleaning

Chemical cleaning is a method to derive surfaces and walls of equipment, pipelines, vessels, kettles and heat exchangers of unwanted contaminants. Chemical cleaning also means the purification, conditioning, treatment or disinfection of water.

Here, we will provide you with an overview of all chemical cleaning methods and their applications. We will also name alternatives and environmentally friendly solutions.
• Limestone removal and scaling prevention for heat exchangers, pipelines and kettle walls
• Biofilm removal for equipment that has been in touch with water
• Legionella disinfection
• Surface disinfection and suture activation with UV-radiation
• Ozone disinfection and oxidation for several applications
• Surface corrosion treatment
• Scent removal off walls, pipelines
• Corrosion prevention in CV-pipes, aluminum silo’s and systems with various materials

Biofilm removal and control

A biofilm is a layer of microorganisms contained in a matrix (slime layer), which forms on surfaces in contact with water. Incorporation of pathogens in biofilms can protect the pathogens from concentrations of biocides that would otherwise kill or inhibit those organisms freely suspended in water.
Biofilms provide a safe haven for organisms like Listeria, E. coli, and legionella where they can reproduce to levels where contamination of products passing through that water becomes inevitable.
It has been proven beyond doubt that chlorine dioxide removes biofilm from water systems and prevents it from forming when dosed at a continuous low level. Hypochlorite, on the other hand, has been proven to have little effect on biofilms.


Legionella control


In the prevention and control of legionnaires disease (legionella) causing microbes, chlorine dioxide has taken an eminent roll. The specific characteristics of the disinfectant make sure ClO2 gets the job done where others fail.
Biofilm in the piping can protect legionella from most of the disinfectants.
Chlorine dioxide, however, removes the biofilm and kills bacteria, spores, and viruses.

Other advantages are:

1.    The bactericidal efficiency is relatively unaffected by pH values between 4 and 10;
2.    The required contact time for ClO2 is lower;
3.    Chlorine dioxide has better solubility;
4.    Chlorine dioxide does not react with NH3 or NH4+;
5.    It destroys THM precursors and increases coagulation;
6.    ClO2 destroys phenols and has no distinct smell;

Corrosion treatment

Corrosion treatment is a kind of water treatment that serves the prevention of corrosion in plumbing systems of various materials, such as rustproof steel, carbon steel, copper and aluminum.

Many drinks of water and process water transporting pipelines have corrosion problems in open or closed ring pipes or cooling and heating processes as a consequence of the use of several metals, such as rustproof steel, carbon steel, copper and aluminum and as a consequence of badly conditioned water.

Galvanic corrosion

When two metals are connected with one another in the near to an electrolyte a reaction consists. This is called galvanic corrosion. The noble metal will corrode last during such a reaction.

Open plumbing systems

An "open system" means that the water in a plumbing system can come in contact with outside air and, as a result, with oxygen. The system is open because of a connection with an open storage barrel or a vertical pipe. Oxygen dust or contaminants may be added to the system in time through the openings.

Oxygen and contaminants that are added to the system can enhance microbial activity. Consequentially biofilm formation may occur. This may cause negative effects, such as slime formation and stuffing of pipes and heat exchangers.

The MACK Group can offer various solutions to these problems, for instance, UV-disinfection, ozonization, bio dispersant dosing, and other chemical solutions.

Next to these effects, corrosion may occur as a result of the application of various materials, such as copper or rustproof steel pipes and carbon steel pumps.

The MACK Group can offer and dose corrosion inhibitors, to introduce corrosion protection in pipes and pumps. These inhibitors, which may be based on phosphates or phosphonates, will pacify and protect rustproof and carbon steel parts from corrosion. The MACK Group often advises companies to use softened or demineralized water (low chlorine levels and no precipitation of hardness increasing salts) in the pipes. The MACK Group also advises pH control and an increase of the pH of the circulating water to pH 9.2 - 9.5. The corrosion speed on metal is very low at this pH.

For systems that will often be out of order for longer periods of time we advise companies to maintain low but continuous water flows through pipelines, in order to prevent standstill corrosion.

We also often advise companies to apply partial stream filters for the removal of small suspended matter, which derives of peeled-off matter from the inside of the pipes and corrosion products. These filters were developed to continually filter the water of CV and cooling systems of building installations and to remove iron particles (iron oxide; rust particles) and sludge. The filters we recommend are a combination of magnet filters and bag filters that are fitted directly on the main returning pipe.

Closed plumbing systems

Within closed plumbing systems corrosion may also come about. Even though companies always make sure they use pure water as a starting point and there is no possibility of oxygen addition to the system, corrosion can still occur on various sites in the plumbing system.
This kind of corrosion is called anaerobic corrosion. Anaerobic bacteria will reduce certain substances, such as sulfate, and consequently, corrosion will come about. The anaerobic processes that cause the corrosion will function optimally at a pH of between 7 and 8. The resulting substances are a precipitate of iron hydroxide (Fe(OH)2) and iron sulfide (FeS).

Sampling equipment and measurements

The MACK Group can supply companies with various test sets for the monitoring of several parameters, such as pH, conductivity, hardness, microbial contamination and inhibitor concentrations.

If you would like us to advise you on the situation of your plumbing system and the steps you can take to remove and prevent corrosion, please send us an overview of the arrangement of your system and your water analysis.
If necessary we could perform water analyses for you.


Hot and cold water systems

The advantages of using chlorine dioxide with hot and cold water systems have already been shown at the descriptions on legionella. There are however more advantages:

1.    The bactericidal efficiency is relatively unaffected by pH values between 4 and 10;
2.    Chlorine dioxide is clearly superior to chlorine in the destruction of spores, bacteria's, viruses and other pathogen organisms on an equal residual base (even cryptosporidium and giardia);
3.    The required contact time for ClO2 is lower;
4.    Chlorine dioxide has better solubility;
5.    No corrosion associated with high chlorine concentrations. Reduces long term maintenance costs;
6.    Chlorine dioxide does not react with NH3 or NH4+;
7.    It destroys THM precursors and increases coagulation;
8.    ClO2 destroys phenols and has no distinct smell;
9.    It is better at removing iron and magnesia compounds than chlorine, especially complex bounds.
Information on legionella in fountains is also available
For more information or advice on the treatment, measurement, and prevention of legionella please feel free to contact us by mail, fax or telephone.
    

Chemical Remediation

In situ chemical oxidation (ISCO), a form of advanced oxidation processes and advanced oxidation technology is an environmental remediation technique used for soil and/or groundwater remediation to reduce the concentrations of targeted environmental contaminants to acceptable levels.

Environmental remediation deals with the removal of pollution or contaminants from environmental media such as soil, groundwater, sediment, or surface water. Remedial action is generally subject to an array of regulatory requirements, and may also be based on assessments of human health and ecological risks where no legislative standards exist, or where standards are advisory.

In situ chemical oxidation

In situ chemical oxidation (ISCO), a form of advanced oxidation processes and advanced oxidation technology is an environmental remediation technique used for soil and/or groundwater remediation to reduce the concentrations of targeted environmental contaminants to acceptable levels. ISCO is accomplished by injecting or otherwise introducing strong chemical oxidizers directly into the contaminated medium (soil or groundwater) to destroy chemical contaminants in place. It can be used to remediate a variety of organic compounds, including some that are resistant to natural degradation.

Chemical oxidation is one half of a redox reaction, which results in the loss of electrons. One of the reactants in the reaction becomes oxidized, or loses electrons, while the other reactant becomes reduced, or gains electrons. In ISCO, oxidizing compounds, compounds that give electrons away to other compounds in a reaction, are used to change the contaminants into harmless compounds. The in situ in ISCO is just Latin for "in place", signifying that ISCO is a chemical oxidation reaction that occurs at the site of the contamination.

The remediation of certain organic substances such as chlorinated solvents (trichloroethene and tetrachloroethene), and gasoline-related compounds (benzene, toluene, ethylbenzene, MTBE, and xylenes) by ISCO is possible. Some other contaminants can be made less toxic through chemical oxidation.]
A wide range of groundwater contaminants react either moderately or highly with the ISCO method, and ISCO can also be used in a variety of different situations (e.g. unsaturated vs saturated ground, above ground or underground, etc.), so it is a popular method to use.

What is the chemical decontamination?

Decontamination (sometimes abbreviated as decon, dcon, or decontam) is the process of cleansing an object or substance to remove contaminants such as micro-organisms or hazardous materials, including chemicals, radioactive substances, and infectious diseases.

The purpose of decontamination is to prevent the spread of micro-organisms and other noxious contaminants that may threaten the health of human beings or animals, or damage the environment.
Decontamination is most commonly used in medical environments, including dentistry, surgery and veterinary science, in the process of food preparation, in environmental science, and in forensic science.

Chemical Decommissioning

Relocating, downsizing, or shutting down a laboratory can feel daunting. Years of experiments lead to an accumulation of chemicals that require appropriate handling and disposal and equipment that must be decontaminated and decommissioned. Workspaces must also be decontaminated prior to being vacated. Opting for decontamination and decommissioning service provider with the ability to design a custom plan based on your lab’s specific needs while adhering to health and safety requirements ensures a smooth transition.

Chemical disposal requires significant expertise and stringent documentation. Prior to packing and removal, a full chemical inventory must be completed, and all containers must be appropriately labeled according to safety data sheets. Proper labeling and packing are also critical for transport to a disposal facility or a new lab. It is important to know which chemicals can and cannot be shipped together and to comply with DOT and EPA regulations. Depending on the size of the lab, this may be extremely time consuming, and improperly labeled containers and unknown waste containers pose further challenges. Fortunately, numerous vendors employ well-trained staff capable of completing a full inventory, as well as chemists and technicians capable of identifying unknown waste.

Decommissioning and removing equipment pose unique challenges as well. Every institution will have a series of regulations pertaining to de-energizing, decontaminating, and removing equipment from laboratories. The type of work done in the lab will also determine which decontamination protocols are necessary. For some labs, unplugging and cleaning a device may be sufficient, while for those in which radiation is present, a much more rigorous protocol is required. Several service providers are able to address decontamination, certification, and packaging, ensuring the instrument can be safely removed and transported.

For labs moving to a new facility, these service providers also offer reliable shipping and tracking to ensure sophisticated equipment arrives at its final destination in working order. Alternatively, if an instrument is no longer needed, there are options for recycling and resale. Some services will pick up equipment, return it to a facility for debranding, and manage the sale of the item. For equipment that is not destined for resale, there are multiple recycling services that will accept unwanted equipment such as autoclaves, microplate readers, mills, ovens, glassware, microtomes, cryostats, etc., keeping additional waste out of landfills. Other organizations, such as Seeding Labs (Boston, MA), accept equipment donations for distribution to low- and middle-income countries.

Finally, the lab space itself must be decontaminated. Many labs have multiple areas with specific decontamination requirements, such as fume hoods, animal facilities, and cold rooms. Services that work with certified industrial hygienists and environmental health and safety consultants are best equipped to decontaminate lab space and provide the appropriate documentation.

Moving or closing a lab does not have to be a monumental task. Many service providers have highly trained staff capable of performing chemical identification and disposal as well as equipment decontamination and removal. Working with a decommissioning service keeps lab personnel safe from hazardous chemicals and contaminants and keeps old equipment out of landfills.