A comprehensive guide for chemical dosing systems.

OdourPro on 19 September 2017

Chemical dosing of waste water can reduce odours by up to 95%. OdourPro is the industry leader in Australia for odour management and control, with extensive experience in a variety of industries.

The aim of chemical dosing systems is to control the level of the primary odour culprit, H2S in the waste stream. With the right system, a 95% improvement is possible. Because H2S is corrosive, chemical dosing also prevents corrosion related failures. In addition, OdourPro systems ensure you remain compliant with Work Health Safety (WHS) regulations.

Chemical dosing systems can be applied in diverse industries, like:

  • Municipal Wastewater
  • Industrial Water Treatment and Processing
  • Food and Dairy Processing
  • Abattoirs and Tanneries
  • Meat and Livestock

There are different types of chemical dosing systems, each with their own advantages and disadvantages. OdourPro can help you navigate to the best solution for your needs.

Ferrous dosing

ferrous dosingFerrous dosing units use ferric or ferrous chloride as the dosing agent into the waste water stream. Biochemical reactions in the waste water produce sulphides, which will further react to form H2S gas causing odours unless an alternative reaction is initiated. Ferrous dosing causes the sulphides to bind with the dosing agent forming a precipitate in the waste stream. In this way H2S formation is inhibited and odours are reduced.

Ferrous dosing agents are classified as dangerous goods and must be handled according to Australian standard 3780. OdourPro systems are made of PE or uPVC and conform to Australian regulations. Our technical experts can assist with safe installation and operating practices.

Dosing pumps are linked to the waste water pumps so that the rates of dosing are proportional to the waste water flow. The injection point is located at the pump station wet well or the rising main.

Magnesium Hydroxide dosing

magnesium hydroxideMagnesium Hydroxide is used as a chemical dosing agent to raise the pH of the waste water to a level above 8. At this level of pH, the bacteria that drive the biochemical reactions to produce sulphides and then H2S are rendered inactive. In this way, odours are reduced by preventing the bacteria from producing odour forming compounds. Up to 80% reduction in odours can be achieved using Magnesium Hydroxide dosing.

An additional benefit of Magnesium Hydroxide is the effect it has on solids. Suspended solids are broken down and heavy metals removed from the solution. Sludge from waste streams treated with Magnesium Hydroxide can be disposed of directly to a landfill, thus saving on costs of sludge disposal.

Magnesium Hydroxide systems can plug up if not properly designed and maintained. OdourPro systems come with integrated stirrers in the tank and a dosing line flushing system to ensure continuous flow of dosing agent.

Calcium Nitrate dosing

calcium nitrateCalcium Nitrate is used as a chemical dosing agent to prevent odours because it offers an alternative source of oxygen to bacteria that break down organic waste. Using sulphates in the waste stream as a source of oxygen results in the formation of sulphides and then H2S, which causes odours. When the bacteria are offered nitrates as a source of oxygen instead, odours can be reduced by up to 90%.

Calcium Nitrate dosing agent must be injected as far upstream in the waste water as possible, to prevent bacteria from targeting the sulphates before the chemical dosing point. The wet well station is the most common injection point for Calcium Nitrate.

An advantage of Calcium Nitrate is that it is not classified as a dangerous substance and it is not as prone to plugging.

Micronutrient additives

micronutrient additivesMicronutrient additives promote the growth and reproduction of facultative bacteria. These bacteria can function with or without oxygen and aid the breakdown of organic material without the formation of odours. Using Micronutrient additives reduces both the biological oxygen demand and chemical oxygen demand of the waste water.

Micronutrient additives are often used in stored waste water applications. Some of these additives can be applied as a foam on the surface, which provides a molecular barrier to the emission of odours.

BioStreme products contain natural non-toxic and biodegradable blends of amino acids, essential oils, vitamins, minerals, purines, pyrimidines and complex organic extracts. They are environmentally friendly products that are effective for odour management and control.

Containerised dosing units

OdourPro provides containerised chemical storage and dosing units, which are fully bunded and comply with Australia’s dangerous good legislation. Ten foot containers offer storage up to 20,000 litres of product. Bunds are designed to contain 110% of the total chemical storage capacity.

Containerised dosing units are compatible with any OdourPro dosing skid and come fully equipped with a control panel, safety shower and eye wash fountain. The flexible configuration enables rapid deployment to site and quick relocation from one point to another.

Download: Containerised Dosing Spec Sheet

Case Studies

Some examples of clients have benefited from OdourPro’s chemical dosing expertise and odour management systems are as follows:

Additional resources

OdourPro has a vast selection of resources to inform and guide clients regarding the uses and benefits of chemical dosing systems for odour control:

Contact OdourPro for more information about chemical dosing for odour control

OdourPro has extensive experience in odour management. We treat the odour problem at its biological or chemical cause for a solution that is successful and sustainable. Our technical experts and proven solutions can help your business overcome the challenges of managing odours.

Call our expert team on 1800 510 704 today to arrange a consultation to help you resolve your odour control issues.