Welcome to issue 32, this time we feature a very useful guide that looks at developing a toolkit for effective effluent management. We also continue with part 7 of our serialisation of the UK's primary Legionella control document "Legionnaires' disease: The control of legionella bacteria in water systems", with extracts dealing with preventing or controlling the risk from exposure to Legionella bacteria. We also feature a guide that takes a look at cleaning procedures in the food and drink sectors, in particular reducing the potential environmental impact and costs of cleaning, with particular respect to water use.

In this issue:

• Effluent Management - developing a tool kit for effective effluent management ... more >>
• Legionella Bacteria - HSE's approved code of practice L8, part 7 ... more >>
• Food and Drink Sector - reducing the environmental impact and costs of cleaning ... more >>

Developing a Toolkit for Effective Effluent Management

A recent study has determined the feasibility of developing a Toolkit for the selection of the best effluent management solutions for specialised organicchemicals manufacturers, especially those with ‘hard COD’ problems. Organic chemicals manufacturers generally have complex effluents for which determination of optimum treatment conditions is difficult. The proposed Toolkit would help companies to:

• rapidly characterise their effluent;
• consistently predict final effluent quality;
• determine the optimum-cost effluent management solution.

The following business benefits would result:

• competitive advantage through increasing the speed of response to new product enquiries;
• cost-effective compliance with statutory requirements;
• minimising costs of effluent treatment operations.

Background

Specialised organic chemicals companies produce 35 million m3/year of effluent, spending £55 million/year on treatment. The need to respond quickly to customer demand for products presents particular difficulties due to the complex and changing nature of the wastes. Together with increasing regulatory requirements, this has meant that companies have had to use end-of-pipe technologies that are readily available to treat particular components of the effluent. This may result in many companies having to:

• turn down potential new product opportunities;
• increase capital and operational costs to manage new effluents;
• replace treatment technologies every 2 - 3 years ... more >>

© Crown copyright

For your complimentary copy of this excellent guide please e-mail info@accepta.com quoting the full title of the document.

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Part 7 of the HSE's Approved Code of Practice "Legionnaires' disease: The control of legionella bacteria in water systems"

Preventing or controlling the risk from exposure to legionella bacteria

Approved Code of Practice and guidance

Guidance

55 - Once the risk has been identified and assessed, a written scheme should be prepared for preventing or controlling it. In particular, it should contain such information about the system as is necessary to control the risk from exposure.

56 - The primary objective should be to avoid conditions which permit legionella bacteria to proliferate and to avoid creating a spray or aerosol. It may be possible to prevent the risk of exposure by, for example, using dry cooling plant, adiabatic cooling systems or point-of-use heaters (with minimal or no storage). Where this is impractical, the risk may be controlled by minimising the release of droplets and by ensuring water conditions which prevent the proliferation of legionella bacteria. This might include engineering controls, cleaning protocols and other control strategies. Decisions should be made about the maintenance procedures and intervals, where relevant, on equipment used for carrying out the control measures. Legionella bacteria may be present in very low numbers in many water systems but careful control will prevent them from multiplying.

57 - In general, proliferation of legionella bacteria may be prevented by:

(a) avoiding water temperatures between 20°C and 45°C – water temperature is a particularly important factor in controlling the risks;

(b) avoiding water stagnation, which may encourage the growth of biofilm;

(c) avoiding the use of materials in the system that can harbour or provide nutrients for bacteria and other organisms;

(d) keeping the system clean to avoid the build-up of sediments which may harbour bacteria (and also provide a nutrient source for them);

(e) the use of a suitable water treatment programme where it is appropriate and safe to do so; and

(f) ensuring that the system operates safely and correctly and is well maintained.

58 - The scheme should give details on how to use and carry out the various control measures and water treatment regimes including:

(a) the physical treatment programme – for example, the use of temperature control for hot and cold water systems;

(b) the chemical treatment programme, including a description of the manufacturer’s data on effectiveness, the concentrations and contact time required;

(c) health and safety information for storage, handling, use and disposal of chemicals;

(d) system control parameters (together with allowable tolerances); physical, chemical and biological parameters, together with measurement methods and sampling locations, test frequencies and procedures for maintaining consistency;

(e) remedial measures to be taken in case the control limits are exceeded, including lines of communication; and

(f) cleaning and disinfection procedures.

59 - The scheme should also describe the correct operation of the water system plant including:

(a) commissioning and recommissioning procedures;

(b) shutdown procedures;

(c) checks of warning systems and diagnostic systems in case of the system malfunctions;

(d) maintenance requirements and frequencies; and

(e) operating cycles – including when the system plant is in use or idle.

60 - Detailed guidance on how to effectively prevent or control exposure can be found in Part 2.

more next time ... >>

Extracted with permission from "Approved Code of Practice (ACoP) and Guidance "Legionnaires' disease: The control of Legionella bacteria in water systems" (L8)" © Crown copyright

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Food and Drink Sector: Cleaning

Introduction

This Reference Note has been written to help those who wish to explore reducing the potential environmental impact and costs of cleaning, with particular respect to water use. It specifically does not give advice on how to clean or on specific hygiene standards.

Information

Background

Cleaning is vital to ensure food safety. However, there are many ways that companies can make cleaning more efficient and cost-effective, and less damaging to the environment, without compromising food safety.

As much as 70% of the water used and effluent produced by a food and drinks site is linked to cleaning, and the costs of water supply and disposal are increasing. Excessive use of water for cleaning brings many additional costs, such as those of labour, downtime, lost materials, treatment chemicals and energy for heating and pumping.

While it is the responsibility of companies to ensure that hygiene standards are met, the Environmental Technology Best Practice Programme has provided guidance on how to study, and improve, the effectiveness of water use for cleaning.

Cost Implications

Costs of cleaning will obviously vary from site to site, and between different product lines. It is important, though, to remember that costs are incurred in a number of ways, and that potential savings can be realised from diverse aspects of activity such as energy, chemicals, water and labour. By saving water on some manually controlled and wasteful practices, Programme guidance suggests that up to 98% of water may be saved ... more >>

© Crown copyright

For your complimentary copy of this excellent guide please e-mail info@accepta.com quoting the full title of the document.

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