Consultancy Case Studies

Over the last two decades, in his career as an academic, Simon Judd has provided international water and wastewater consultancy services to a range of clients based across Europe, North and South America, the Middle East and the Far East.

Simon’s work has covered the full range of water and wastewater treatment technology design and operation, including, among other topics: 

  • optioneering for site-specific water and wastewater treatment scenarios 
  • acquisition and provision of supporting information for plant design and operation 
  • trouble-shooting and problem-solving issues relating to existing plants and 
  • ‘sanity checking’ proposed and installed plant designs. 

Examples of recent work include:

  • Technology selection and pilot-scale demonstration, potable water

    Client: UK water utility
    Duration: 43 days

    This job, with a wide-ranging scope and extending over a three-year period, began with a survey of technologies applicable to small-scale surface water treatment for potable water supply. Of particular concern was suppression of chlorinated organic byproduct formation along with reduction of the risk of microbial contamination, and cryptosporidium oocysts in particular. Part of the study entailed a review of membrane integrity test methods and patterns of behaviour in historical oocyst detection. 

    Another major part of the work was a review of pilot/full-scale demonstration of membrane technologies for THM formation abatement with reference to: (a) the rejection of natural organic matter and its discrete constituents (b) the reactivity of the residual organic matter with reference to THM formation, and (c) the membrane hydraulic performance in terms of the sustainable permeability. The work is to culminate in a practical demonstration-scale study of the short-listed candidate NF technologies.

    This work informed a paper, published in ‘Separation and Purification Technology’, on the THM formation propensity of residual natural organic matter in ultrafiltration permeate streams, data being taken from 35 regional UF plants challenged with surface water (Sutherland et al, 2015).

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  • Commercial technology appraisal, ballast water treatment

    Client: UK-based marine engineering, technical and business services organisation
    Duration: 24 days

    A change in international marine legislation prompted the client to fund a comprehensive review of commercially-available and developing technologies for the treatment of ballast water. The review entailed one-to-one interviews with global technology providers (from the Far East to North America) to ascertain the status of their technology, with particular reference to the approval process, along with an assessment of their likely efficacy in meeting the required treated water quality. The outcomes were published in a document published by the client in 2007 (‘Ballast water treatment technology: current status’) and updated in 2012 (Ballast water treatment technologies and current system availability).

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  • Optioneering, industrial wastewater treatment and reuse

    Client: UK-based consumer goods supplier
    Duration: 10 days

    This job entailed identifying the most practical and low-cost option for managing a newly-generated industrial effluent at a site in the north west of England. The effluent was being treated using a DAF plant, the performance and running costs of which were appraised as part of the remit. The scope included an assessment and costing of short-term options for aerobic treatment of both the raw and DAF-treated effluent for sewer discharge vs. tankering based on information provided by the client and available data on biological treatment plant costs. The primary output was a cost analysis spreadsheet evaluating the cost benefit of the preferred option, and specifically the value provided by the dewatering of the waste sludge prior to disposal.

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  • Wastewater treatment technology evaluation, produced water

    Client: Gulf-based oil company
    Duration: 12 days

    The assessment of offshore produced water treatment installations was carried out for a client based in the Arabian Gulf. The job demanded the performance of the technologies to be benchmarked against that reported for other installations, primarily in the grey literature and conference presentations. The work culminated in the publication of a review of the treatment performance and footprint of PW treatment technologies, with the focus being on tertiary treatment by filtration for reinjection (PWRI), published in ‘Separation and Purification Technology’ (Judd et al, 2014).

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  • Troubleshooting, municipal wastewater treatment by MBRs

    Client: UK water consultancy
    Duration: 3 days

    This job entailed the assessment of the design and O&M details to try and overcome a challenge imposed by severe permeability decline following a CIP (clean-in-place) at a small (~2,000 m3/d capacity) plant in Scotland. Two site visits and a number of communications with the client revealed that the recirculation rate through the membrane tank was too low for one of the plants, causing concentration polarisation problems, coupled with a strong clogging and ragging tendency. The ragging challenge was met by installing a rudimentary screen on the RAS. A second smaller plant (~400 m3/d capacity) was subject to severe fluctuations in water quality, demanding equalisation.

    The cause of ragging generally was subsequently identified in a separate research project, the outcomes of which were published in the ‘Journal of Membrane Science’ (Stefanski et al, 2011). This paper was the first research paper published which analysed and quantified ragging in MBRs, as well identifying the root cause.

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  • Troubleshooting, municipal wastewater treatment by MBRs

    Client: Gulf-based properties and facilities development company
    Duration: 9 days

    This job involved assessment of the design and O&M data of a large (>50,000 m3/d capacity) MBR plant in the UAE for which the CIP was failing to recover the permeability. Clogging was evident at this site, and an examination of permeability trends at other MBRs in the region revealed that they were subject to the same problem. Through benchmarking against other sites subject to the same general climatic conditions, it was demonstrated to the client that the design fluxes were overly ambitious and that additional membrane area was needed.

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  • Design parameter identification, municipal wastewater treatment by MBRs

    Client: Swedish consultancy
    Duration: 3 days

    For this job, the basic design parameters for a large municipal MBR (>250,000 m3/d capacity) were required given very strict spatial limitations and a cold climate. It was demonstrated, through determination of net packing densities (taking account of both the in-module packing density and the spacing between the cassettes in the tank) that the options were limited to an HF iMBR (hollow fibre immersed MBR) technology, with appropriate O&M conditions identified from comparable existing large municipal WwTPs.

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  • Feasibility assessment, refinery effluent treatment by MBRs

    Client: International environmental engineering company
    Duration: 3 days

    This job entailed identifying existing MBRs used for petrochemical effluent treatment (~40,000 m3/d capacity), along with their reported design and O&M. Evidence was provided to demonstrate the feasibility of the technology for the application envisaged, specifically with reference to the feed water quality. Performance data (COD removal and sustainable net flux) from other full-scale plants was acquired and collated to identify the most appropriate design and optimum O&M conditions. Specific comparable sites were identified for planned site visits.

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  • Technology assessment, municipal wastewater treatment by MBRs

    Client: Gulf-based municipal wastewater utility
    Duration: 7 days

    This job entailed a review of the design criteria and proposed operation and maintenance protocols for a large municipal wastewater treatment installation in Oman. The work included an assessment of the likely integrity of the membranes, which had been stored for an extended period of time prior to their installation. It was concluded that the storage period and conditions were unlikely to impact significantly on membrane integrity. A four-day short course on MBRs tailored to the client’s needs and delivered to the operators, was provided as part of the job.

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  • Other market surveys and costings

    A number of market surveys and/or cost analyses have been conducted for various international clients based in North America and northern Europe, either planning or in the early stages of commercialising new MBR technologies or related products. These have tended to focus on an analysis of other comparable technologies for general or specific applications, as well as in two cases a review of the membrane material itself.

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