Pollution Detection Sensors, Alarms & PSUs

Introduction

Environmental Innovations work with the world's leading manufcatuers of sensors and transducers. We also have a ISO9001 certified manufacturing facility located in North East London where we both design an manufacture specialist sensors, transducers, alarms monitors and controllers using state-of-the-art thick film hybrid technology.

Thick film is a technology is an ideal media for use in the water industry due to its imense resistance to water and chemical attack. Unlike ordinary FR4 PCB technolgy it is able to withstand direct contact with substances from the extreme of contaminated water through to solvents such as petrol.

Within this manufacturing facility we are able to build complete control systems that integrate sensors of differing technologies and manufcaturers.

Further, we can build fully integrated systems that combine our pollution containment technology with sensors and telemetry.

PH Sensors

These are used to measure the acidity or alkalinity of liquids against the PH scale which ranges from 0 (acid) to 14

(strong alkaline or basic). The scale is not linear so a PH change from one level to

another is 10 times stronger or weaker than the previous. The PH scale is actually the concentration of Hydrogen free ions when compared to distilled (pure) water. So PH0 = 10,000,000 times whereas PH7 = 1 and PH14 = 1/10,000,000.

All of us are fairly familiar with measuring PH using litmus paper from our High School and University Days. This system uses the change of colour on chemically treated paper to give an indication of the PH level against a colour chart. However, this is not very practical for automatic monitoring hence electronic instruments have been developed that can measure PH giving an analogue or digital output, which can be compared against set limits to trigger alarms and to activate drain closure systems such as the Drainstopper^TMor Flapstopper^TM in the event of spills, etc.

The environment is very sensitive to PH changes. A stream will normally have a natural PH of somewhere between 6 and 8. Normal rain will lie between PH 5 and 6.5. However, fish reproduction is stopped below PH5 and fish will rapidly die below PH4. So spilling vinegar PH3, lemon juice PH2 or battery acid at PH1 can be catastrophic!

Turbidity Sensors:

Turbidity is the cloudiness or haziness of a fluid caused by individual particles and suspended solids in water that individually may are generally invisible to the naked eye but collectively form the haze.

The measurement of turbidity is a key test of water quality and its measure can be used as an early warning that something has entered the drainage system. Increased turbidity is often associated with heavy rain where soil / clay can be washed into the water, however it can be used to detect substances such as milk, suspended powders, mixtures, paints, etc that could be spilt and enter the drainage system.

Modern sensors are available to measure turbidity. Many of these look at the optical properties of the medium either looking for optical transmission or back scatter (reflection).

By deploying turbidity sensors up stream in a drainage system it is possible to close of the exit from a site using a Drainstopper^TMor Flapstopper^TM at the exit from the site.

Dissolved Oxygen:

The level of dissolved oxygen (DO) present in lakes and streams is commonly used as an indicator of water quality. Maintaining adequate concentrations of DO is vitally important for supporting fish, invertebrates and other aquatic life.

Companies that discharge nutrient rich substances can have a major impact on the DO level therefore the monitoring and control of discharges is critical. Similarly, spills of substances such as milk and liquid or powered foodstuffs can have a massive impact on the DO in a body of water.

An economic alternative to fitting motorised penstock valves is to use either the Drainstopper^TMor Flapstopper^TM in conjunction with a spilt produce detector such as a turbidity sensors in the plant and a DO monitor located strategically in the body of water.

Temperature Sensors:

Many processes discharge warm water into the environment, however if the amount of discharge increases and is not detected it can be fatal for the fish and other wildlife, plus damaging on the pocket of the business that is wasting energy.

A temperature rise to just 23-25C can be lethal to fish and in summer when the water is already warm a relatively small uncontrolled discharge can devastate a rivers ecosystem.

Simple temperature sensors can be suspended in outflows to measure the discharge temperature from a plant. However, research indicates that the temperature of the body of water should also be monitored and the flow regulated to both keep the temperature down and/or the dissolved oxygen level.

As with PH and Turbidity, the outflow can be controlled / regulated by using products such as the Drainstopper^TMand Flapstopper^TMwhich are very cost effective alternatives than motorised penstock valves.

EIL0027 Power Supply

The EIL0027 is a highly efficient and almost indestructible combined 13.6V dc linear power supply and battery charger that features a fully isolated output, optically isolated mains failure alarm and low battery monitor.

With output charge current automatically limited to 1A, the unit is ideal for float charging batteries of between 0.6Ahr to 24Ahr capacity or supplying either constant or pulsed loads.

Two versions of the power supply are available to cater for 230V or 110V mains supplies.

Technical Description

 

The EIL0027 utilises a high efficiency 30VA toroidal step down isolation transformer, bridge rectifier and smoothing capacitor to feed an integrated linear float charge regulator. The regulator output is fixed at 13.6V, the recommended float charge voltage for 12V lead acid technology batteries. In addition the regulator features overload current limiting and thermal protection making it virtually indestructible under most operating and fault conditions. Output noise is 40dB better than EMC limits compared to switch mode designs between 30MHz to 1GHz 40dB making the unit ideal for powering noise sensitive devices such as radio receivers and sensors.
The incoming mains supply is constantly monitored by a voltage comparator circuit with integrated delay timer and optically isolated open collector output. The delay timer provides a nominal 2-seconds delay to guard against the majority of false alarms generated by switching surges and short-term supply brownouts. Under normal conditions, i.e. mains healthy, the alarm output is energised to provide a failsafe circuit for connection into a normally closed alarm or telemetry loop circuit.

The battery monitor circuit is provided to warn against low battery conditions generally, once the mains has failed and the backup battery has been carrying the load for some time. As with the mains failure alarm the battery monitor alarm includes a nominal 2-second delay timer to cover load  switching surges etc.

Hanger Bracket (European Registered Design 4010363)

Unique to Environmental Innovation and what makes us market leaders in our field is our fully adjustable, counterweighted Hanger Bracket designed to support and retract underground transducers and sensors at depths ranging from 400mm to almost 3m below ground. 

Hanging from a "U" notched wall the bracket the Hanger Bracket is fully retractable from above ground eliminating the need to enter the drains to either install or retrieve a tranducer thus easing calibration and cleaning.

Available with a straight tail or cranked tail to permit the horizontal or vertical mounting of sensors etc. Manufactured from 8mm x 40mm galvanised mild steel.

 

How it Works: Now no need to enter confined spaces!

 

Sensor Interfacing for Automatic Spill Containment