Abstract: The present invention relates to a coagulant composition comprising a coagulant and a carbon source compound, wherein the coagulant is selected from the group iron and aluminium salts, or any combination thereof. The carbon source includes methanol, ethanol or glycol. The present invention further relates to a method of treating wastewater, e.g. containing nitrogen and/or phosphate, including providing the coagulant composition to wastewater before, during and/or after a biological treatment step, and the use of the coagulant composition in wastewater treatment.

Abstract: The present invention relates to a coagulant composition comprising a coagulant and a carbon source compound, wherein the coagulant is selected from the group iron and aluminium salts, or any combination thereof. The carbon source includes methanol, ethanol or glycol. The present invention further relates to a method of treating wastewater, e.g. containing nitrogen and/or phosphate, including providing the coagulant composition to wastewater before, during and/or after a biological treatment step, and the use of the coagulant composition in wastewater treatment.

Abstract: The present invention relates to a process for purification of water, comprising addition of an alkalinity affecting material, which material is chosen from calcium, sodium and/or magnesium containing compounds, addition of a coagulant containing ferric salt in an amount of about 3.5-40 mg Fe3+/l water to be purified, and addition of hydrogen peroxide in an amount of about 0.2 to 15 mg/I water to be purified, wherein said water to be purified has an alkalinity of about 0.05-0.9 mmol/l and an amount of total organic carbon (TOC) of 5-25 mg/l, and said alkalinity affecting material is added before the coagulant and hydrogen peroxide.

Abstract: A fire protection system is provided including spray nozzles a pump unit, a control system with pressure-measuring mechanism, and piping for conducting extinguishing medium from the pump unit to the spray nozzles. The pump unit includes pump drives, each of which comprises a pump and an AC electric motor. The AC motor can be connected to an AC electricity network via a contactor device, in which pump unit the AC electric motors are controlled on the basis of the pressure measured in the piping. One of the electric motors is controlled by means of a frequency converter such that the motor steplessly adjusts pressure and the others are started up into the network as steplessly adjusting motors.

Abstract: Control method and control apparatus of the electric motors of a pump unit of a fire protection system, which fire protection system comprises spray nozzles (112), a pump unit, a control system with pressure-measuring means, and piping (105) for conducting extinguishing medium from the pump unit to the spray nozzles, which pump unit comprises pump drives, each of which comprises a pump (101) and an AC electric motor (102, 203a-203f) rotating it, which AC motor can be connected to an AC electricity network via a contactor device (206a-f), in which pump unit the AC electric motors are controlled on the basis of the pressure to be measured in the piping, and in which one of the electric motors (102, 203a-203f) at a time is controlled by means of a frequency converter (108, 204) such that the motor to be controlled with the frequency converter operates as a motor that under the control of the frequency converter steplessly adjusts pressure and the others are started up into the network as steplessly adjusting mot