Energy Efficiency Best Practice Guideline for Pump & Pumping Systems

Pump and Pumping System is an Efficient Way to Reduce Energy Consumption

Pumps are used for a wide range of applications to transfer fluids through mechanical action. According to the basic operating principle, pumps can be classified as either dynamic pumps or positive displacement pumps. Dynamic pumps are further classified into centrifugal pumps and special-effect pumps. Positive displacement pumps are further classified into rotary pumps and reciprocating pumps. Centrifugal pumps account for the major share of electricity consumption in the industrial sector. Some of the centrifugal pumps used by the industry include:

1. mono-block pumps

2. end-suction pumps

3. split-case pumps

4. multistage pumps.

Different standards of pumps, not just for India but all over the world are available. In this article, we will see the latest Guidelines issued by EC regarding pump and pumping systems. This EC guideline can be applied in India for the country.

1. Management and control The industry shall undertake the following:

A. Operate pumps close to the best operating point as specified by the OEMs. It shall ensure optimum loading of the pumps.

B. Use pumps with the highest efficiency to meet the baseload when multiple pumps are in operation.

C. Install variable frequency drive (VFD) for fluctuating loads instead of throttling.

D. Use online monitoring for centralized large systems and periodical measurement for decentralized smaller pumps.

E. Use several smaller pumps in parallel operation in place of the single pump of higher capacity.

F. Manage and control the loading of pumps near the best operating point of the respective characteristic curve in case of multiple pumps in operation.

G. Manage the piping network of the pumping system and the control operating parameters, such as flow rate, pressure, and temperature to meet process requirements.

H. Replace worn-out pumps with energy-efficient pumps.

I. Maintain a minimum Net Positive Suction Head (NPSH) of pumps as prescribed by the manufacturer.

2. Measurement and recording

The industry shall measure and record the following:

A. Key operating parameters such as the total differential head, flow rate, and electricity consumption to evaluate the efficiency of pumps on monthly basis.

3. Maintenance and inspection

The industry shall undertake the following:

A. Check the condition of gland sealing on daily basis and undertake maintenance to avoid leakages.

B. Inspect the pump for vibration and noise levels every quarter.

C. Inspect and ensure proper tension of belts for belt-driven pumps.

D. Undertake periodical maintenance including overhauling of the pumps according to the instructions provided by the OEM.

E. Ensure dynamic balancing of pump assembly after each overhauling.

F. Calibrate instruments and gauges as per the recommendations of the suppliers to ensure reliability and maintain the accuracy of data.

4. Necessary measures when installing new facilities

The industry shall consider the following:

A. Install pumping network using seamless/ FRP pipes for minimum system resistance.

B. Use a booster for small loads requiring higher pressures.

C. Select correct capacity of the pump with energy-efficient systems, such as IE3 motor or permanent magnet synchronous motor, variable frequency drives (VFDs), etc., to avoid energy wastage.

D. Install suction valve of proper size as recommended by OEM.

Target components

The industry shall:

A. Ensure pump efficiency is close to the design values provided by the OEMs.

B. Replace rewound motors in pumps with IE3 motors.

The industry shall estimate pump efficiency using the following formula:

Pump Efficiency (%)= (Hydraulic power×100)/Shaft power

Hydraulic power (Pd)=Q × (hd–hs) × ρ × g / 1000

Pump shaft power (Ps) = Electricity consumption × Motor efficiency

where,

g=Acceleration due to gravity (m/s2)

hd=Discharge head (metre)

hs=Suction head (metre)

Q=Flow rate (m3/s)

P= Density of fluid (kg/m3)

Source= ENERGY CONSERVATION GUIDELINES FOR MSME SECTOR by BEE, MoP, India.