Bring Up to Shape

Uzbekistan depends heavily on artificial irrigation. One of the central economic sectors in Uzbekistan and essential for 90% of its agricultural production, it is the main source of income, especially in the rural areas and municipalities. Given the sector’s importance, the government introduced two programs in order to significantly improve national agricultural productivity and sustainability, and thus raising overall living standards in rural areas. The goal is to modernize the irrigation and drainage systems to achieve higher productivity together with better environmental protection.

These plans include the country's largest pump irrigation system, Amu Bukhara. This plant supplies water to the Uzbek provinces of Bukhara and Navoi. The network was built in 1965 on the right bank of the Amu Darya River. It provides water for the irrigation of about 250,000 hectares of land, cities, local industries, and more than 1.7 million people.

However, after more than 50 years of continuous service, its major and minor channels are in desperate need of modernization. Irrigation efficiency is only 40% and thus represents a significant risk to agricultural production and the regional economy. Furthermore, the obsolete and energy-inefficient pump stations not only require large amounts of electricity, they also represent a large environmental impact, emitting some 758,000 to 935,000 tons of CO2 emissions annually.

The government, together with the support of the Asian Development Bank (ADB), is implementing a comprehensive overhaul and modernization program of the system. This includes the construction of a new pumping station as well as the modernization and refurbishment of four existing stations.

In the case of the Amu Bukhara project the Chinese infrastructure company Hebei Construction Group is acting as the Engineering, Procurement, Construction (EPC) contractor. With strictly defined awarding criteria, ANDRITZ was awarded the contract for the delivery of the core components. Accordingly, ANDRITZ is supplying a total of 16 custom-tailored pumps, including their respective spare parts, for two pumping stations.

The pumps for the two stations of Amu Bukhara are highly technical and whose development and production meet the detailed project-specific requirements. For the Kizil Tepa station, 10 tailor-made vertical volute pumps are being produced – each with an efficiency of up to 90%. They reach a head of up to 75 m and a flow rate of up to 440,000 m3 per hour.

For the second station, Kuyu Mazar, six customized vertical line shaft pumps with similarly excellent efficiencies are planned. They reach a head of up to 24 m and a flow rate of up to 414,000 m3 per hour.

These hydraulic machines are also designed to take into account the increasingly variable characteristics of the river. Equipped with a hydraulically adjustable mechanism to vary the impeller’s angles by up to 15°, it is possible to respond reliably and promptly to changes in head and flow rate even during pump operations.

Additionally, by varying the impeller diameter and the trailing edge, an exact adaptation to achieve the desired operating points can be made and efficiency can be optimized. This mechanism demonstrates clear advantages where significant changes in the flow rate occur and is characterized by a long life with no requirement for any electronic components.

Alongside the design and delivery of the pumps and spare parts, installation and commissioning will be supervised by ANDRITZ personnel. Completion of the entire project is scheduled for June 2020.

Great hopes are being pinned on the success of this major infrastructure project. Harnessing sufficient water reserves for reliable irrigation of agricultural land is expected to bring about sustainable changes in terms of much-needed better living conditions for future generations in these Uzbek provinces.

Author: Vera Muellner