Environmental & Bio Engineering Lab

Waste water is drawn from a floor-standing feed tank (not supplied) by a DC motor-driven peristaltic pump. Rotational speed – and thus flow rate – is accurately set by a ten-turn potentiometer. The pump delivers the feed to the reactor vessel through a transparent lid. Air is supplied at a measured rate by a small compressor, and discharges into the base of the reactor via a spider-arm dispenser. This design prevents blockages and produces sufficient bubbling for stirring and reaction. The liquid level in the reactor is maintained at a constant value of five to ten liters, by an adjustable overflow device connected to the outer annular chamber of the vessel. Dissolved oxygen and pH probes and meters are included. The reactor lid contains a gas exit port, suitable for sampling the gases for subsequent analysis

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 days

Water is taken from the laboratory mains supply and is fed to the settling tank via a flow meter. For studies of sedimentation, slurry is prepared in a sump tank and pumped via a specially designed flow meter to join the fresh water stream just before entry to the settling tank. Well-mixed slurry of known concentration and flow enters the tank uniformly under the inlet weir. The sump tank is continually agitated by a flow sparging device to prevent settling of solids during an experiment. For hydraulic tracer and visualisation studies, an accurate dye injection system is provided. A known volume of dye solution is injected just before the entry to the settling tank.

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 days

The Filterability Apparatus utilizes a bed of granular material, which can be chosen by the investigator to suit their own purposes. The measurements taken with this apparatus enable a filterability number to be calculated, which has significance in deep-bed filter performance. For example, the effects of changing pre-treatment dosing can be evaluated before making changes on the operating plant. Solenoid valves enables the operator to select the direction of flow through the granular bed. At the base of the column is a sieve mesh to retain the granular media. Wastewater can either flow downward via gravity from the funnel into the column to demonstrate filterability or via a pump to demonstrate head loss characteristics using an electronic pressure sensor. 

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 days

The anaerobic digester comprises two five-liter upward-flow packed bed reactors with feed rate and temperature control facilities. This allows steady, continuous operation at up to seven liters per day over periods of several days. The reactors may be operated in series or parallel. A buffer vessel between the reactors permits discharge of excess flow from the first reactor when the second reactor is operated in series but at a lower flow rate. The flow rates to the vessels are set and controlled by calibrated peristaltic pumps. The temperature of each reactor is controlled by an electrical heater. The temperature distribution within each reactor is maintained to ±0.5°C. Reactor temperatures may be separately set at any desired value in the range ambient to 55°C. The gas off-take from each reactor is taken to a volumetrically calibrated collector vessel operating by water displacement. A constant head, liquid seal device ensures the gas pressure in the reactor is maintained at a constant value throughout the test run. The collected gas can be exhausted from the vessel and the volume refilled with water during a run without breaking the liquid seal. Liquid and gas sampling points are located at all strategic points around the reactors. Non-return valves and liquid seal syphon breaks are included in the process pipework to ensure each reactor operates at a constant volume without the ingress of air or the danger of accidental syphonic action. The equipment is mounted on a vacuum-formed plastic base with an integral drain channel to cope with spillages and wash down. 

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 days

The Aeration Unit comprises an open tank equipped with a propeller stirrer. Air is supplied via a compressed air line through a pressure regulator valve, and through a flow meter to a diffuser positioned within the tank. A variety of diffusers are included. The dissolved oxygen content of the water in the tank is measured by means of a dissolved oxygen probe, which includes direct reading of water temperature. Mounted on the base is the clear acrylic water tank. On the front of the tank is a depth scale and at the base a drainage tap. The digital stirrer control includes speed measurements, this is supported by a metal bar. Sparger tube, treble airstone and single airstone may be separately attached to the aerator tube. Variable-speed adjustment of the stirrer paddle provides different levels of turbulence in the tank.

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 Days

The equipment allows for the well-known ‘jar tests’ to be conducted on water samples requiring treatment to determine the correct coagulant dosage on a laboratory scale as a prelude to full-scale plant operation. Flocculation and coagulation are preliminary tests carried out prior to designing a water or waste water treatment plant. Jar tests are routinely used for the control of plant operations and they serve to indicate the optimum chemical dosages for removal of turbidity and colour, necessary pH adjustments and the supplemental use of activated carbon. Jar tests yield a wealth of evaluation of agglomeration rate as a function of energy input (paddle speed), settleability of the floc formed and the clarity of supernatant water (which might be related to the subsequent length of filter run).Coagulation and flocculation tests may be used, in conjunction with other tests, to study basic processes, eg the kinetics of reaction, filterability index and the removal of trace constituents from aqueous solutions.

• Production Capacity: 5-10 Piece
• Delivery Time: 30-40 days