D-Rainclean Pollution Control System from Hoofmark (UK) Ltd

Heavy metal waste water pollution originating from vehicles is becoming increasingly recognised as a source of contamination of ground water.

Hoofmark include a number of heavy metal pollution control products in the range which have been developed to remove or control pollution run off and the spread of hydrocarbons and some heavy metals.

The Problem Of Pollution Run Off From Vehicles

On heavily trafficked roads and adjacent parking areas, between 5 and 15 metres from the carriageway, heavy metal waste water reaches critical concentrations and heavy metal waste water regularly exceeds the threshold values for pollution run off.

Composition Of Heavy Metal Waste Water

Exhaust gas, abrasion dust, losses due to drips and corrosion are the most important sources of pollution run off in road traffic. In the combustion chamber of engines a large number (up to 150) of Polycyclic Aromatic Hydrocarbons (PAK) are formed into pollution run off which requires heavy metal pollution control.

Apart from ‘PAK’, monocyclic aromatics such as benzene, toluene, xylene and phenol are given off. Petrol engines emit around 3mg/km of benzene, petrol engines with a catalyst around 0.5mg/km. Over and above the exhaust gases, chromium, zinc, copper and nickel are given out, in total around 0.1-1 mg/km plus around 0.05 mg/km of cadmium.

Tyre abrasion alone is taken as 120 g per kilometre of road per 100 vehicles, per year. Along with difficult to break down organic compounds, zinc, cadmium, lead, copper, chromium and nickel are emitted. Due to abrasion of brake linings the heavy metals nickel, chromium, lead, zinc and particularly copper occur.

With road wear on asphalt roads, it is predominantly mononuclear and poly-nuclear aromatic hydrocarbons that have to be reckoned with, particularly ‘PAK’.

Corrosion on bodywork releases heavy metals dependant on the paint mix and steel alloy used. Hydrocarbons, lead, zinc, chromium and copper have been found in coolant along with mineral oil. All these factors require a method for treating heavy metal pollution such as the D-Rainclean pollution control system.

The Solution to Pollutant Run-off

The above contaminants are cleansed by the D-Rainclean pollution control system before reaching the ground water using petrol interceptors. Cleansing of pollution run off is achieved by filtration, adsorption and deposition, ion exchange, precipitation and biological breakdown. Soil contamination and pollution of water courses and groundwater is prevented by heavy metal pollution control.

Suitability as a Planting Site

It is not necessary to plant the D-Rainclean filtration channel. In the event that planting of the D-Rainclean filtration channel is required, the D-Rainclean filter media was developed to be very low in nutrients. The selected soil cover will nevertheless provide an adequate supply of nutrients.

D-Rainclean Filtration Channel

The construction of the D-Rainclean filtration channel in special plastic with a high load bearing capacity enables:

• fulfilment of the requirements of the ATV regulation A138
• space saving, easy and secure installation
• freedom of design for the surrounding areas
• ability to be traversed by cars
• protection from compaction of the filter media
• easy filling or replacing

Suggestion for Planting

If the D-Rainclean filtration channel is used as an open channel (i.e. without a cover) it can be planted e.g. to each compartment 2 pachysandra, or 2 mahonia and vinca minor, or 1 cotoneaster in varieties.

Application Examples

Car-park installation options enclosed or open top (also planted) with overflow into D-Raintank.

 

Frequently Asked Questions about D-Rainclean

See our FAQs page for questions about D-Rainclean.