Milford Haven STW - A Wastewater Case Study

Project Profile

Having completed the installation of escalator screens and screenings handling at Garnswlt STW working direct with DCWW and their South West Capital Delivery team, HUBER were asked to look at a similar type of project at Milford Haven STW. The main difference between the two sites was that the site at Milford Haven was a raised inlet works and located inside a building. This was from the outset of the project a challenge for all involved with the  space available being very limited and all the equipment supplied would have to be Ex rated.

The existing INKA step screens and Parkwood compactor were close to the end of their asset life. HUBER had previously carried out repairs on the inlet screens just 3 months prior to our visit and had warned that spares for both existing screens were getting more difficult to procure. Also, it was noted that the existing screens were struggling to cope with the first flush, which required the local operator to remove large volumes of screenings by hand into a receptacle and dispose into a skip on regular basis and thus becoming a major health and safety issue.

An initial site survey undertaken by Adrian Heneghan, HUBER’s Area Sales Manager, highlighted that this could not be done without some help from a local DCWW contractor. Whitland Engineering were the closest and came recommended by DCWW. Another site visit was made and between HUBER and Whitland, scopes of work were agreed and an order was placed on both companies by DCWW to proceed with the project.

Huber Technology Supplied

• 2 off EscaMax® 4000/652/6 Duty/Standby for 400l/s each
• 1 WAP/L BG4
• Local Control Panels
• Local Push Button Stations

Objective

The challenge of getting 2 new escalator screens and a WAP/L compactor into a confined space while keeping the site running was a major feat in itself. Phase 1 of the project was getting the HUBER control panels and push button stations delivered 2 weeks prior to the screens. This allowed Whitland Engineering time to get them into position and pre-cabled ready for the new equipment.

Phase 2, was for the mechanical installation. The site had upstream storage for 4-5 hours which allowed a reasonable time to remove the old Parkwood compactor and install the new WAP/L BG4 screenings handling unit into a temporary position so as not to hinder the installation of the screens.

Phase 3, with the WAP/L running, one of the INKA step screens was isolated and removed allowing the other to run and keep the plant operational. The new EscaMax® was then installed and cabled ready for commissioning.

Phase 4 involved removing the 2nd INKA step screen and installing the other EscaMax® unit. Again, once cabled the screen was then ready for commissioning immediately.

Solution

Throughout all the phases of the project execution, detailed planning and effective communication between Huber Technology, Whitland Engineering and the DCWW capital delivery team was essential. A collaborative approach and good working relationship between the 3 companies ensured that this challenging project was delivered on time and within budget.

David Alford – Contracts Engineer – Huber Technology:
“As always with projects having a large amount of site work we encountered a few challenging moments throughout the installation phase but by good communication and working closely with Whitland Engineering we were able to overcome these with a successful outcome and a satisfied customer.”

Mark James – Milford Haven Site Operator:
“Thanks to all involved in getting these screens in and running while keeping the site running. I can now spend more time looking after the rest of the site without having to watch the inlet screens and manually remove screenings. From a health and safety point of view, this is a bonus. The screens and screenings handling are all working really well.”