Application of distribution energy efficiency platform in reducing electrical energy consumption of municipal sewage plant

Abstract: Sewage treatment plants play a huge role in alleviating the increasingly serious problem of water pollution in cities. However, the high operating cost and electricity cost make the sewage treatment plant fail to obtain the expected benefits, which affects the effectiveness of sewage treatment. Therefore, it is necessary to reduce the operating energy consumption through effective energy-saving measures. Based on the practical experience, the author discusses some thoughts and understandings about the countermeasures to reduce the electrical energy consumption of sewage plants.

Key words: power supply and distribution system; Lighting system; Power monitoring; Power quality monitoring; Electrical fire monitoring

0 Introduction

At present, the increasingly tense situation of energy, which requires that the sewage treatment plant can use less energy to obtain greater benefits. Sewage treatment plant as the vanguard of energy conservation and emission reduction, but also energy-intensive enterprises, its operating costs and electricity bills have been high, therefore, how to save energy, reduce electrical energy consumption, improve economic efficiency, is the problem that urban sewage plants need to think about.

1 Energy saving and consumption reduction countermeasures for power supply and distribution system

1.1 Reasonable layout of substation

The substation should be set in the load center as much as possible, so as to reduce the distribution radius, reduce the cable cost and line loss, and also improve the stability and safety of the power supply.

1.2 The power supply and distribution series should be reduced

At present, the total power load of most sewage plants is 1000 ~ 10000kW, the power supply voltage is 10, 20 or 35kV, and the electrical equipment is 0.4, 6 or 10kV, so we should minimize the distribution series and reduce the loss of the power distribution link.

1.3 Reasonable selection of transformer capacity

Reasonable selection of transformer capacity and the number of units can make it run near the best economic load rate, and the number of transformers can be reasonably adjusted according to the nature of electricity consumption, reducing the waste of electrical energy caused by light load of transformers.

1.4 Improve the power factor of the power supply and distribution system

Increasing the power factor of the power supply and distribution system can reduce the reactive power loss of lines and transformers, so as to achieve energy saving. Due to the improvement of the power factor and the reduction of reactive power, the apparent power and load current required to supply the same load power are reduced, and the transformer capacity and line cross-section can be more reasonably selected, which can save energy and achieve the purpose of reducing investment. The power factor can be improved by:

① Use electrical equipment with high power factor when selecting equipment.

② The sewage plant where the electrical equipment is low-voltage equipment adopts the low-voltage centralized compensation method, which is conducive to management; However, for equipment with very low power factor, local compensation devices should be used for reasonable compensation, such as ultraviolet disinfection equipment, because the power factor is very low, it should be compensated in its control equipment, which can effectively reduce the reactive power loss of the line.

(3) For high-voltage motor equipment with a long power supply distance, a separate compensation device should be used for reactive power compensation.