Bio Resource Treatment Framework at Kinneil Kerse

Procurement exercise for a supplier to de-water and treat liquid wastewater sludge with lime to produce a biosolid that meets an enhanced treated standard as defined in the Biosolids Assurance Scheme (BAS). Rates to include supply of an appropriately sized centrifuge, lime treatment and storage equipment, treating, conveying the sludge cake to a storage location agreed on site, and operators.

To de-water and treat liquid wastewater sludge with lime to produce a biosolid that meets an enhanced treated standard as defined in the Biosolids Assurance Scheme (BAS). Rates to include supply of an appropriately sized centrifuge, lime treatment and storage equipment, treating, conveying the sludge cake to a storage location agreed on site, and operators.

The cake storage bay shall be configurated by the supplier to meet their needs and be their responsibility. There are prefabricated “tombstones” that may be used, any additionally required material for creating the cake bay shall be provided by the supplier.

It is the supplier’s responsibility to ensure the placement of any materials to create the cake bay are positioned safely. The type of lime used in the process must not be liquid; any powdered or granulated lime is acceptable.

All equipment must be suitably sized to deal with daily production levels of indigenous and imported bioresource. The supplier will require an odour management plan and commit to adhere to this for the duration of the framework.

The odour management plan must satisfy all parties, namely Scottish Water, SEPA (Waste Management Licence) and the Local Authority (The Odour Code of Practice). All prices should include supply of documentation and data with respect to operational performance and relevant legislation, codes of practice and other relevant standards.

Full transparency of all activities performed by the supplier is expected. Daily communications with the local Scottish Water Operations team will be required, and a weekly meeting held.

Electrical, water and wastewater services will be made available within the sludge storage/treatment area for use in providing the required service. It is the supplier responsibility to confirm the available services are suitable.

Sludge from the onsite holding tanks will be a mixture of indigenous SAS from the onsite sequencing batch reactor (SBR) tanks and imported sludge from various satellite sites. The sludge holding tanks do not currently have mixing capabilities and the total make up of sludge will likely be a high ratio of SAS and potentially lower than ideal dry solids.

(Data can be provided on request). This should be taken into consideration when providing suitable equipment.

In addition to indigenous sludge there will be a requirement for cake import equipment able to treat up to an approximate additional 13,500 wet tonnes of imported cake per annum which is estimated to be between 20-24% dried solids. This is an estimate only using recent output figures following decommissioning of digesters at Stirling and Dalderse WWTW’s.

This figure may fluctuate. Any additional capacity for cake imports would be welcomed to provide contingency for import restrictions elsewhere in the network.

The supplied centrifuge should be capable of dealing with peaks in the sludge production. Equipment should be able to operate at approx. 40m3 per hour flow throughput through the supplied centrifuge and lime plant, of sludge whilst maintaining a solids capture rate of 97% +/- 2% in the return liquors.

Equipment breakdown should not impact the ability of the successful supplier to accept business as usual cake imports. Additional information: https://atamis-scottishwater.my.salesforce-sites.com/ProS...