“Transparent, unbiased, professional advice”
TruSense was appointed by a prominent UK Water company to carry out feasibility studies and detailed process design for the upgrading and extensions to 4 activated sludge plants with a total capacity of 254,000 m3/d average dry weather flow. The upgrading and extensions were to cater for both growth until 2025 as well as compliance with a more stringent final effluent consent limits coming into effect in 2015 under the EU Fresh Water Fisheries Directive.

TruSense worked closely with the client offering the following services:

  • Wastewater analysis and characterization
  • Process option evaluation
  • Detailed process design for modifications to existing units and new extensions
  • Whole plant modelling to optimize process design and performance under various loading conditions and maintenance
  • Preparation of design reports
  • Client process design support and co-ordination with D & B contractors
Thorough assessment of existing capacity and optimisation of process design and operating parameters using advanced process modelling resulted in substantial overall capital and cost savings.

The Project was recognised by the client for business excellence and was a top 3 finalist at the Water Business Excellence Awards (2012) in the Sustainability/Carbon Impact Category.

We are involved in a number of projects that optimise existing treatment plants. Through a combination of process audits and application of mathematical modelling we have provided cost effective solutions to a wide range of problems for our clients. Some of our projects are as follows:
  • Assessment of existing treatment capacity for a combined trickling filler and activated sludge plant (15 000 pe) receiving a high industrial load from a confectionary factory.
  • Assessment of aeration capacity for an activated sludge plant (600 000 pe) with fine bubble diffused aeration. The plant had old diffusers and an assessment of the efficiency and capacity of the existing aeration system was required. Recommendations to supplement the aeration system using floating aerators in sections of the aerobic zone resulted in delaying complete refurbishment of the aeration system until the next capital investment cycle.
  • Optimisation of an Activated Sludge Plant (120 000 pe) failing to meet final effluent ammonia limit. Modelling resulted in recommendations on the operating sludge age, management of sludge liquors and change in aeration taper within the aerobic zone.
  • Optimisation of a chemical industrial pre-treatment plant (15 000 cubic metres per day) to ensure compliance with the discharge to sewer permit.
TruSense was appointed by the East Rand Water Care Company to perform a detailed and comprehensive assessment to confirm the true rated hydraulic and treatment capacities of 7 wastewater treatment plants. The treatment processes range from trickling filters to complex biological nutrient removal activated sludge plants with anaerobic and aerobic sludge digestion. The objective of the project was to determine the optimal capacity of the Works enabling ERWAT to efficiently plan for future capacity requirements.

Services offered included, collection and analysis of plant data, treatment and hydraulic capacity evaluation and optimization, preparation of engineering report and O&M manuals

Optimization and re-rating involved both physical plant audits of all treatment processes as well as application of mathematical modelling to optimize process design and performance. Apart from determination of optimal capacity of the existing works

  • Details of refurbishments required for the existing plant to achieve the re-rated capacity
  • Optimum operating and control parameters for the existing plant to achieve final effluent compliance
  • Operation and control strategies to minimize aeration energy and chemical consumption
  • Recommended optimal capacity of future extensions for the given design horizon as well as appropriate technologies to be considered
  • Maintenance scenarios and protocols under re-rated flows and loads
TruSense worked closely with ERWAT staff to ensure the following:
  • Recommended modernisation and future expansion technologies match ERWAT’s long term technology strategy taking into cognisance current industry trends towards energy neutral wastewater treatment plants
  • Operation, control and maintenance strategies for these plants were developed to match ERWAT’s overall wastewater treatment plant operation and maintenance strategies
TruSense Process Engineering was retained by a prominent UK Water Company to undertake a Sewage Treatment Works Cost Modelling project. The primary objective of the project was to understand current baseline sewage treatment whole life costs and how these could be reduced through further optimisation or with the installation of new technologies available on the market. These costs will then be compared to novel sewage treatment research and development (R&D) possibilities and the results will be used to informthe Asset Management Programme 6 (AMP6) investment to look at the most appropriate projects and also inform the business’ sewage treatment long term strategy.
Seven treatment works representative of the sizes and treatment technologies across the Water Company’s base were selected as case studies namely:
  • 3 No. trickling filters plants
  • 1 No. trickling filter and activated sludge
  • 2 No. activated sludge
  • 1 No. sequencing batch reactor
Services provided by TruSense included
  • Collection and analysis of site wastewater and process performance data
  • Baseline and optimised baseline process and cost modelling
  • New technologies process and cost analysis
  • Aggregated financial analysis
  • Preparation of project report
New technologies that are not currently applied within the company that were evaluated included traditional enhanced biological phosphorus removal (EBPR) activated sludge, external nitrification, pure MBBR and IFASas well as mainstream de-ammonification.