ATEX Rotary Piston Pump for Biodiesel Transfer

Renewable Fuels

Renewable fuels are more common every year and rightly so as studies show they release up to 80% less carbon dioxide (CO2) emissions than conventional petroleum-based fuel. After the introduction of new energy policies in Europe demanding the usage of more clean energy and lower carbon fuels, biofuels have become one of the most popular renewable energy sources, with biodiesel being perhaps the most common type.

Biodiesel is made from vegetable oil or animal fats, producing fuel from vegetable oil is not something new, in fact the original diesel engine invented by Rudolf Diesel in the 1980s in ran on vegetable oil. To produce biodiesel from vegetable oil, the oil is mixed and agitated with a specific volume of alcohol and a catalyst that is added to accelerate the chemical reaction of the two components. The end result of this process is a combination of biodiesel and glycerine also called glycerol, which being heavier lays at the bottom of the container, the glycerine is then removed and a cleansing process takes place to ensure the quality of the biodiesel.

Customer's ATEX Requirements and Points to Consider

Our customer, a UK based biodiesel plant that makes high quality biodiesel out of canola oil required a biodiesel transfer pump to handle the oil after being filtered, this is a critical step in the production process and therefore the equipment used has to be extremely reliable as well as having low maintenance requirements in order to keep downtime to a minimum also. Although the fluid is not flammable, the equipment supplied must be ATEX (explosion proof) as it is installed in a declared non-safe zone 2 hazardous area within the plant. The main challenge on this application was to supply a pump they can use in the future once the plant upgrade is complete, as the current location where the pump is being installed is only temporary. The flow rate requirement on the future location will not change, however the discharge pressure will, the customer only requires the pump to overcome a head of 10 metres to start with, however our pressure drop calculations indicated that once the equipment is relocated, the total head will be 42 metres, this included a 15% margin precaution.

Our North Ridge NR-RPP Rotary Piston Pump Selection

Being a volumetric positive displacement pump type, our NR-RPP Rotary Piston Pump range is the best solution for this application, these pumps can maintain an almost exact capacity throughout a wide range of different pressure values. The unit supplied, our 1 inch NRRPPAX3-EX2HP is capable of producing 60 l/min at 1 bar and 57 l/min at 4.2 bar, taking into account the increased power consumption when pumping at the higher pressure value, we supplied the pump with a 1.5kW ATEX EExd II C T5 - 3 phase motor.

The North Ridge NR-RPP positive displacement pump range is an ideal solution for fuel and oil transfer applications, they have fantastic self-priming capabilities, the largest 6” models have a max. capacity of 64 m³/h (1066 l/min) and pressures up to 12 bar (120m). These are quite often used for fuel dispensing applications alongside a filling nozzle and pressure relief valve.

Some of the main benefits of the North Ridge NR-RPP range are:

•        ATEX Certified Upon Request

•        High Efficiency Even with Highly Viscous Fluids

•        Temperatures Up to 300 °C

•        High Self-priming Capabilities

•        Capable of Handling Viscosities Up to 200,000 cSt

•        Reversible – Clockwise and Anticlockwise 

Specific details of the pump supplied to our customer are as follows: