Optimisation

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Optimiser processes seek to attain optimal operating conditions (for example :- lowest fuel usage, fastest delivery route etc.) whilst satisfying a set of rule based constraints (e.g. maximum and minimum pressures, number of compressors to be used, max / min compressor speeds, operating control bands, load sharing across sites etc.). Any requirement can effectively be optimised with energy usage and speed of throughput being the most frequently requested applications. The optimiser can consider any combination of influencing parameters such as equipment items, pipe characteristics, fluid properties, additives, setpoints and operating ranges such as tank levels.  The following are some of the more common optimisation processes provided :-

Pump / Compressor Optimisation can consider individual station configurations or complete pipeline / network configurations The user specifies the required output flowrates and the input pressure and defines whether units are available or not. The optimiser exhaustively searches every combination of pump / compressor and control valve settings whilst ensuring that it satisfies the predefined rules until the optimal operating scenario is established. The output from the optimiser is a ranked list of the most efficient pump / compressor and control valve setpoint configurations for each station.

Heater optimisation assists the operator in determining the most efficient configuration within a station or combination of stations on a pipeline or network. It is often incorporated into the pump / compressor optimisation so that an entire optimisation process can also consider the heaters. The heaters can be made to operate in series or in parallel to increase the flexibility of their operation.  

Pump in SumpSump Optimisation

The pump start / stop optimisation process is used within the water industry to optimise the pump start and stop levels within the sump. Pumps are frequently set to start and stop at the highest and lowest possible levels in the belief that minimising the number of pump starts and stops results in minimised power usage. In certain cases, extending the start and stop levels will improve efficiency of operation but allowing the water level to fall to its minimum level every time the pump starts means that the static head between the sump level and the discharge location is always maximised. The energy required is at its maximum when the water level in the sump is at its minimum. If the stop level is optimised, taking into account the inflow to the sump, and pump operating efficiency, energy usage levels can also be optimised. By connecting the optimiser to the load forcaster, future expected conditions can be taken into account further improving the efficiency of performance.


Throughput Optimisation

Optimise routes and valve states to determine the fastest delivery of product from one location on the pipeline network to another. The user specifies available valves and required flowrates and the optimiser will output a ranked list of valve settings that have been optimised against time.

Nominations and Storage Optimisation

Nominations and Storage Optimisation is usually adopted for gas pipelines although it can equally be applied to liquid pipelines. As part of the optimisation process, nominations are defined for supply and customer demand locations (variations in flow with time). The output from the optimiser will include time based variance in inventory within the pipeline and storage facilities in addition to optimised valve routings and capacity levels.