Mobile Water Services help deliver EPC projects on time

Mobile Water Services help deliver EPC projects on time

Timely performance, cost saving, quality and safety are essential to all parties involved in a construction project. The construction process is however subject to many variables and unpredictable factors that could impact the successful delivery of a project. Mobile water services are a great option for EPC companies to ensure meeting their client’s water requirements safely and within the specified cost and timeframe.

The key success indicators of a construction project include its completion within the planned budget and schedule, and within the required quality, safety, and environmental limits. However, a project slipping over its planned schedule is a common problem for engineering, procurement and construction (EPC) companies. To the owner, any delay means loss of revenue through non-availability of production facilities. Delays can also cause higher overhead costs to the contractor due to a longer work period and additional workforce, as well as higher material costs.

When project costs or schedules exceed their planned targets, client satisfaction is impacted which can have effects on contractors and consultants in terms of relationships, mistrust, litigation, arbitration, cash-flow problems, and diminished support of the company’s stakeholders. Completing projects on time is not only an indicator of efficiency, but is also essential to a company’s financial health and reputation.

The construction process is subject to many variables and unpredictable factors, which come from many sources. EPC companies notably face a number of challenges for the supply of treated water for the commissioning and start-up of new facilities or even the continuous operation of existing assets during planned maintenance, and the late life management and decommissioning of a plant. These challenges range from water system flushing, condenser cleaning, pipework and tank hydro testing, and steam blows through to cold start-up of assets, risk mitigation on the late delivery and start-up of a permanent water treatment plant, and minimization of potential downtime during maintenance.

Commissioning on time and within budget

Provision of temporary water treatment is well established and Veolia Water Technologies’ Mobile Water Services are well placed to meet the requirements of EPC companies. Mobile water solutions are commonly used during the start-up phase of a new power facility for instance. They can support an increased demand for purified water for applications such as boiler cleans, pipework flushes and steam blowing — which remove construction debris, sand, mill scale, etc. — from critical systems, including air-cooled condensers or steam turbine lines. This ensures optimal equipment cleanliness, enabling efficient plant operation for daily power generation. Mobile water solutions can be brought on site to purify the water for this process and then removed when the water demand resumes to normal operating levels following the commissioning activities.

A mobile water treatment plant can also be used if there is a delay in the delivery and start-up of the permanent water treatment plant, which could hold up the project and incur financial penalties. The mobile water treatment plant can be provided to treat the raw water available and produce the desired quality and quantity for any commissioning needs. The mobile plant could also substitute the permanent one to allow the project to go into full-scale operations. This may mitigate any delays in meeting the client’s requirements.

Planned maintenance and turnarounds

EPC companies also need to plan for maintenance of their clients’ existing water systems. Mobile water services can be brought in to cover equipment servicing, ensuring that production or business processes can continue and avoiding costly downtime.

Scheduled turnarounds may involve a total suspension of operational activities. A turnaround that exceeds its timeline or budget can have serious financial consequences, so it is essential that an efficient, reliable water supply is available as needed. In these instances, mobile water services can be brought in to support all maintenance and cleaning activities. They can also bridge a gap for operators with a problematic plant until it can be replaced or repaired, or even to bridge a time period if there are variations in feed water supply or quality, as demonstrated by the experience of the service company of one of the world’s leading chemical groups.

The client provides production facilities and utilities for its customers in a chemical park. The individual plants in the park, usually supplied with demineralized water by the client, encountered problems with the raw water filtration which led to considerable operational issues. Our team of mobile water services quickly mobilized assets to produce 200 to 250 m3/h of treated demineralized water in accordance with VGB standards — a German guideline for feed water, boiler water and steam quality for power and industrial plants — in order to meet the treated water demands required for the chemical park’s customers without interruption for a period of three months. This short-term intervention offered a reliable and secure, 24/7 supply of deionized water in continuous operation.

Preventative maintenance and refurbishment of a permanent water treatment plant needs to be carried out more frequently without interrupting the production schedule. A temporary water treatment system may be deployed to either provide the full replacement or partial part of the various processes during this interim need. Typical applications include resin replacement, pressure vessel maintenance, control upgrades, reverse osmosis membrane cleaning or replacement, maintenance on chemical dosing equipment and work on waste treatment plants.

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Temporary and flexible water supply during decommissioning activities

There are numerous processes and stages to be completed during a decommissioning project while the water treatment plant is required to continue to provide treated water throughout the project, as all the stages are completed. The quantity of water required by the site may reduce; the feedwater may change due to other decommissioning activity, causing uncertainty for the process. On-site water treatment plants that have been designed for a certain throughput may not be able to effectively manage the varying flow rates or feed water changes and may also be expensive to maintain.

For planned decommissioning activity, Mobile Water Services provide a reliable, secure and flexible supply of treated water to support the project. It is also possible to use these systems in the case of unforeseen events.

A nuclear power station was being decommissioned in the UK, generation ceased, and the plant had to be defuelled. Originally, during nuclear power generation, the site consumed some 900 m3/d of demineralized water for steam raising and cooling but, once generation ceased, this reduced to about 26 m3/d. This meant that the on-site demineralization plant was larger than required and costly to maintain; our client wanted to decommission and de-man it but they still needed a supply of demineralized water.

We provided the demineralized water requirement at the site using a trailer-mounted mobile demineralization plant which provided ion exchange demineralization using similar technology to the station’s on-site plant but at a much reduced flow. Instead of in-situ regeneration, when the ion exchange resins became exhausted, the trailer was simply returned to our central regeneration and recycling service center. This meant that there was no requirement for chemicals or for effluent disposal which could have created health and safety issues and interfered with the defuelling work.

Our teams remotely monitored the trailer, which was changed every month. Our client calculated that this reduced the costs by 50% compared with operating the on-site plant and also allowed early removal of the redundant demineralization plant.

Awareness is key

Mobile water services can bring numerous benefits to EPC companies. It is important that this thinking is factored into commissioning, maintenance, and decommissioning plants, as it is not uncommon for these processes to demand more water than originally anticipated. As awareness grows, we can expect to see mobile water services being implemented more frequently, supporting planning and helping EPC companies to deliver projects on time and on budget while maintaining resilient and effective water treatment plants in the process.