EquipmentIn order to ensure effective protection of the equipment being treated by Aquaresult inhibitors, it is necessary to maintain design inhibitor concentration in the circulation loop, as well as to provide strict chemical dosing rate in the particular point of process route, for example, upstream of heat exchanging equipment. To execute this task metering stations are used. These stations comprise, as a rule, service tank with chemical, proportioning unit with piping and control and protection system of diverse complexity. The simplest option provides for manual control of proportioning unit with use of built-in functions for flow rate adjustment. The simplest flow rate adjustment method is change in length of piston stroke by means of mechanical appliances.
cranking mechanism to transform the rotary movement of the motor shaft
into reciprocating motion of the piston pushing out
metered compound via ball valves system. It was used widely
on chemical and power facilities in the last century
More sophisticated method — varying the speed of reciprocating motions made by the pump at metering. Combined solutions are also used. Modern pumps enable metering with account for varying back pressure, with feed time adjustment, which allows mitigating fluctuations of concentration at low delivery flow, when the chemical is supplied to the loop with portions at specific time intervals.
a wide range of flow rates and large number of functions. Environmentally friendly, reliable, simple in
control and adjustment, easy in repair and maintenance
Flow meter controlling the metering pump flow rate is added into the metering system to introduce corrections for water flow in the process cycle. The most preferable and convenient method for inhibitors proportioning control is the use of special controllers enabling automation of virtually the whole metering process. Depending on the software shell options the controller can sum up the flow rate values per several makeup lines without need for acquiring additional totalizers, process various types of signals from flow meters and sensors, perform automatic biocide treatment of the cycle on the basis of set schedule, bring standby pumps into operation automatically in case of the main pump failure, execute automatic switchover between the main and standby pumps to optimize remaining life of both pumps. Controller equipped with network interface or 3G, GSM module provides for remote control and monitoring of all parameters, as well as accidents and errors logging. Of course, the price of automated station is significantly higher of the simple pump with manual control, but, with regard to the processes with instable and frequently changing conditions, as well as when reliable, continuous keeping the concentration is required, the stations equipped with controllers and standby pumps significantly reduce the cost for operating personnal
Modern inhibitors metering station on the basis of microprocessor controller (to the left in the upper corner). Mounted in special container, equipped with service tanks of “IBC” type, digital metering pumps, stand for measuring the corrosion and monitoring the conductance and pH value of the medium being treated.