P15
SUMMARY Optimum water treatment will help prolong the lifetime of pipes and critical components in the DH system. By desalination, deaeration and pH adjustment, the lifetime increases. Consider a business case where the lifetime of the pipes was increased from 50 to 70 years. The important measures to avoid corrosion are: • Reduce the conductivity in DH water by use of demineralized water and keep oxygen out of the system. Salts and oxygen are powerful catalysts for corrosion. • Avoid unnecessary use of chemicals. Chemically speaking, oxygen reacts faster with steel than oxygen binding agents. Chemicals also increase the conductivity, the risk of forming sludge and they act as nutrients for corrosive microbiological growth.
GRAPH 2: CORRELATION BETWEEN PH, CONDUCTIVITY AND SALTS
The above graph for one of the distribution networks clearly shows problems with raw water break-in. This clearly occurs in the period from April to the beginning of July 2019, where chloride, sulphate and conductivity increases while the pH value slightly decreases. After this period the leakage stopped, and the parameters returned to normal.
For further information please contact: Thomas Dalsgaard, td@silhorko.dk
NIRAS Energy Private as well as public investors prefer NIRAS’ international experience within district heating and biogas plants. This applies to both renovation of existing plants and establishment of new plants. We provide expert consulting through- out the entire process – from business plan and authority approvals to design and tender documents. We supervise the construction phase and during commissioning.
Expert consulting – all the way from idea to commissioning PURE ENERGY
www.niras.com
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