Mirrico Seminar, Kazan, September 2011Paul Wood and Anna Vatsurina

Outline

Learnings from an incident Review Risk, Hazard and Exposure Exposure issues Examples of how Dow Microbial Control, controls exposure to

biocides Packaging Labelling Safe Removal Transport Lab Safety Storage

Dosing Suggestions Conclusions

Everyone Learns from an Incident

Biocides are not dangerous when handled correctly

Chemical Handling: Level of Risk

• Hazard Type or Consequence of Exposure

Corrosive = will cause burns (contact may not be detected immediately)

Toxic = a poison

Respiratory irritant = like household bleach or ammonia

Skin sensitizers = cause “skin allergy”

• Exposure Potential or Likelihood of Event

How much product ?

Probability of an exposure ?

Two factors to determine the risk when handling a chemical

Hazard x Exposure Potential = Risk

Level of Risk

Priority in hazard management reduces the exposure potential

Hazard = HIGH LOW LOW

Hazard = HIGH HIGH HIGH

SafeEthanol =x

UnsafeEthanol =x

There are many routes to exposure

Exposure Potential

Inhalation Skin Ingestion

How do we come into contact with a chemical ?

Types of Workplace Exposure

Gloves left lying on the floor

Water collecting on top of a drum

Contaminated cleaning cloth left in a bin

Opening, moving, connecting / disconnecting,

emptying apparently “Empty” drums

Containers used for hazardous materials without

labels

Cleaning / repair of contaminated installations

Door handles / Doors opened by someone wearing

gloves

Exposure to biocide residues

Types of Workplace Exposure

Spills from damaged packaging, or pipe work

Dosing from drums, or pails manually

Decanting from drums, or pails into smaller vessels

Using samples

Collecting samples from the production process Taking samples for Quality Control of raw materials

Samples shipped to customers

Handling samples in the lab.

Exposure to liquid biocides

Exposure Control

Perform a hazard- and safety analysis of the intended task according to your internal rules ( EHS review )

Follow the recommendations on MSDS* and Labels

Installations and tools you intend to use for the planned task

PPE (Personal Protective Equipment): type and control intervals

Appropriate ventilation of the working place / area

Safety installations: Safety Showers / Eye rinsing stations

Industrial Hygiene / Cleanliness and Housekeeping

Working Instruction

Spill-/Leakage Handling

Emergency Procedures

Training !!!

If there is the potential for exposure

Biocide Packaging

Containers Have to be UN approved

3H1/Y1.4/150/** GB/3380

Stringent testing

Drop tested

Are fitted with tamper evident

seals for security reasons

Are palletised to prevent damage

The number of drums are limited

on a pallet to prevent overhang

and restrict weight

Packaging ergonomics

Packaging has to be designed to be safe

On Site Signs & Labelling

Signs placed around the workplace inform

operators on which and when personal

protective equipment should be worn in

specific areas

In addition use educational posters as part

of an on-going safety education program

Product labelling is one source of information but there are others…

Personal Protective Equipment ( PPE )

• Helmet

• Goggles• Suit• Gloves

• Rubber Overshoes

Burns caused by not wearing gloves

Burns caused by improper removal of gloves

To avoid mishandling and accidents

Always ensure samples are clearly labelled

Warning symbols are visible

Store products in clearly labelled cabinets

To prevent exposure during use

Handle biocides in a fume cupboard

Make sure lab technicians wear the correct protective clothing:

Gloves

Goggles

Ensure the area where biocides are handled is kept clean

Lab Safety

Warehouse Storage

Store biocides safely

• To maximise the safety of people Training Keep pedestrians separate from product Safety barriers around offices Special bins for hazardous waste Ventilate warehouse

• To prevent blind corners, or falling containers Restrict pallet height

To avoid mishandling

Use painted areas

Good lighting

Suggestions

Be proactive

Review the MSDS and label warnings

Do a safety review of the job

Have a written procedure and follow it

Evaluate and inspect the equipment to be used

Inspect your Personal Protective Equipment

Have the spill deactivation kit equipment and chemicals in place before an incident occurs!

18

Why use biocides ?

Essential To:

Maintain Efficient Heat Exchange Prevent Corrosion Prevent Plugging of Orifices Prevent Potential Health Concerns Maintain Aesthetic Appearance

19

Why use biocides ?

Microbes can be:

algae if light reaches the collection basin

aerobic bacteria

anaerobic bacteria (SRB’s)

Moulds and yeast

20

Bio-films

Microbes can attach to surfaces and produce slime

impairs the heat transfer

induces microbial corrosion (MIC)

clogs filters, screens, casings and nozzles

potentially harbours Legionella pneumophila

Biofouling Control – Biofilm Issue

A biofilm is a layer of slime that is produced by microbes after they attach to a surface Biofilms serve to protect the microbial community that is

underneath it Corrosion and H2S production result from the growth of microbes

within a biofilm Removing biofilm is more difficult than preventing the formation of a

biofilm

Stage 1Conditioning

Layer

Stage 2Bacterial

Attachment

Stage 3Slime Formation (EPS Production)

Stage 4Slime

Thickening

Stage 5Slime

Detachment

Examples of “Patchiness” in Bio-films on 316 Stainless Steel

23

Review of the active ingredients used in indistrial water cycles

24

Oxidisers

Cl2, HOCl, Br2, HoBr,

Chloramaines ; ClO2, H2O2 / Peracetic acid

Corrosive Very fast acting Effect is short-lived – no permanance Generate high levels of AoX ( adsorbable organic

halides )

1, 5-pentanedial

OO

H H

Glutaraldehyde

Quick kill (1-3 hours) under alkaline conditions (pH 7-9)

Broad spectrum efficacy Highly effective against SRB, biofilm, and Legionella Readily biodegradable at concentrations < 5-ppm Compatible with dispersants, surfactants and most

WT chemicals, including CMIT/MIT Compatible with halogens and other WT additives Does not contain or release formaldehyde Kills via cross-linking proteins in cell wall

Glutaraldehyde Features

Weak efficacy versus fungi and algae Stability with ammonia (NH3) and alkaline pH

De-activated by bisulphites Polymerises under alkaline and high temperature

conditions (haziness / yellowing) Evaporation (volatilization) potential increases with

temperature and /or aeration

Glutaraldehyde Limitations

DBNPA

2,2-dibromo-3-nitrilopropionamide

CC

C

N

BrBr

O

N

H

H

Registered ApplicationsCooling Water (Re-circulating / Once-through / Open / Closed)Retort Systems, PasteurizersReverse Osmosis MembranesAir Scrubbers and WashersPaper MillsAdditives/Mineral SlurriesEnhanced Oil RecoveryPublicly Owned Treatment Works

DBNPA Features

Extremely fast acting (15 - 60 min) Broad spectrum efficacy Highly effective against biofilm and Legionella Effective at low dose levels Easy to dose liquid Non-corrosive at in-use concentration Low environmental impact Short half-life at more alkaline pH’s Kills via reactions with sulphydryls and

disruption of respiration and metabolism

DBNPA Limitations

Liquid product shelf life is limited (6 months) Weak versus fungi and algae Low solubility in water Incompatible with strong nucleophiles and

reducing agents Not UV stable Occasionally referred to as an oxidizer

THPS

P

HOH2C

CH2OH

HOH2C

CH2OH

+SO4 2-

2

tetrakis(hydroxymethyl) phosphonium sulphate

Feature Benefit

Fast acting, broad spectrum Control of wide range of microorganisms

Active against SRB; Algae and Legionella

Useful for a wide range of industrial applications

Dissolves FeS Reduces FeS related problems such as fouling of equipment

Low dosages Cost effective

Favourable aquatic toxicity Very low impact on ecologyand minimal effect on environment

Degradation to inert components

Non-foaming Easy to use in high-flow systems

No organic solvents Safety in use; completely water miscible

THPS

THPS Limitations

Known to release formaldehyde rapidly (25% of total dose)

Cationic properties react with anionic inhibitors

Not compatible with oxidizing biocides

Unstable at high pH

Issues with use of THPS in high calcium waters

Registered Applications Recirculating Cooling Water (Open and Closed) Air Washers & Industrial Scrubbing Industrial Process Water Brewery Pasteurizers and Can Warmers Industrial Wastewater RO / UF Membranes (non-medical; non-potable) Pulp and Paper Slimicide Additive and Slurry Preservation

CMIT / MIT

CMIT / MIT Features

Broad-spectrum activity Provides control over bacteria, algae, and fungi with no performance gaps. Effective vs Legionella, SRB, and biofilm

Fast Acting Provides immediate control circa 10 minutes

Stable over a wide range of pH (<9) and temperature (<40° C)

Effective under conditions typically encountered in most processes

Clear, water soluble, liquid Fully water soluble at use levels and easy to dose

Broad chemical compatibility Compatible with most cooling water and papermill additives and biocides

Low use rates Cost effective

Biodegradable and does not generate AOX or formaldehyde

Environmentally friendly

Product Feature Customer Benefit

Poor stability above pH 9 and >40º C Poor stability with nucleophiles and reducing agents

(sulphides, sulphites, amines,) Perceived weakness versus SRB Slow killing Safe handling concerns / sensitization / burns New solid version will address safety issues

CMIT / MIT Limitations

Oxidizing DBNPA Glutaraldehyde THPS CMIT/MIT

Products Cl2/HOCl

BCDMHClO2

AM 7287Sump Buddy

UCARCIDE 24, 50 AQUCAR THPS 75

KATHON WT

Rate of kill Very very fast

Very fast Fast Fast Slow

Persistence No No Yes Yes Yes

Thermal resistance Excellent Medium Excellent Good Medium

pH range 4 - 7.5 Up to 8.5 Up to 9.5 Up to 9.5 2 to 9

Organisms A,B,F A, B, F biofilm ++

A, B, (F) biofilm +++

A, B B, F, Y, M

Biodegradability n.a. Fast (readily biodeg.)

Very fast (readily biodeg.)

Inherently biodegr.

Inherently biodegr.

FA release No No No Yes No

Comparison of Biocides for WT

Actives Used for Industrial Water Treatment and Paper

Biocide Cooling Water

Air Wash. RO / UF PaperSlimicide

Glutaraldehyde x x x x

DBNPA x x x x

CTAC x

CMIT/MIT x x x x

DCOIT x x

Spasibo