Hardness Removal

Introduction: This guide describes Finnish practices for managing industrial wastewater and provides instructions for drawing up an industrial wastewater agreement. The purpose of this guide is to provide support for all those who are involved in decision-making concerning the conveying of industrial wastewater to sewers and the safe treatment of it at municipal wastewater treatment plants. The guide describes the industrial wastewater related legislation currently valid in Finland, information on different types of industrial waters, instructions for preparing an industrial wastewater agreement, formula of increased fee, monitoring of industrial wastewater and practical examples of functional solutions. The guide describes the various stages in drawing up an industrial wastewater agreement and matters that have to be taken into account in preparing such an agreement. The aim of this guide is to provide as many concrete examples and instructions as possible. However, when preparing an industrial wastewater agreement, it is always recommended to use case-specific discretion and take the local circumstances in account. The specific properties of industrial wastewater must be taken into account in the industrial wastewater agreement. The quality of wastewater conveyed to the sewers has impacts on the occupational safety of the employees of the water utility, the condition of the sewerage network and equipment of the treatment plant, the operation of the treatment process, the sludge quality and the state of the recipient water body. All these aspects must be taken into account in the agreement.