Frequently oil is produced while, simultaneously, large amounts of water are produced as well. Under these circumstances it is important to have compact and efficient deoiling equipment at one's disposal. After some remarks on otherde-oiling methods, the attention in this paper is focused on three separationtechniques: plate separation, centrifugation and the use of hydrocyclones. The working principles are described and subsequently typical data on separation efficiency, geometry of the separator section, separator volume and critical oil-droplet diameter are derived or given. Analysis of these data shows, that the ranking with respect to performance of the three separator types is: centrifuge, hydrocyclone, plate separator. In the last section of the paper attention is given to some recent developments concerning centrifugation and the use of hydrocyclones. P. 391

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The development of a compact oil-water separator is pursued through theoretical and experimental investigation of a number of separation techniques. Plate separation is an effective separation method for oil droplets with a diameter of about 50µm or larger, but ineffective for smaller droplets. Use of gasflotation or of oil coalescence in a porous medium as separation techniques leads to the removal of a part of the smaller oil droplets present in oily waters. To increase the separation efficiency each of the last two techniques will be combined withcentrifugal separation. A design of a separator based on such a combination is presented for both gas flotation and oil coalescence. INTRODUCTION De-oiling equipment at offshore oil-production platforms must preferably be light and compact, and the oil concentration of the discharged production water must be below the prescribed limit. In many cases these requirements are not met. This paper describes work on the improvementof de-oiling equipment with respect to size and efficiency. Three de-oiling techniques are studied:Plate separation. This is a suitable technique for the removal of oil droplets above a specific diameter. In practice this diameter is of the order of 50µm.Dissolved gas flotation and oil coalescence in a porous medium. With these two techniques also smaller oil droplets can be removed. PLATE SEPARATION A plate separator consists of a pack of parallel plates, through which oily water is led. To enhance the removal of the collected oil the separator is usually placed under an angle with the horizontal, and provided with corrugated platesl. The rise velocity of the oil droplets is determined by the density difference between oil and water and the friction force exerted on the rising oil droplet. It can be shown2 that this results in a stationary rise velocity:(Available In Full Paper) The use of a plate separator leads to complete removal of all oil droplets above a specific diameter, the critical oil-droplet diameter. The numerical value of this parameter depends on the dimensions of the plate separator and on the velocity of the oily water, and can be calculated as2 :(Available In Full Paper) In case the angle with the horizontal is larger than about 10 degrees, it is necessary to correct for the tilting of the separator by replacing H by H/cos ? in eq. (2). Experiments and results Experiments on plate separation were carried out in straight and in corrugated channels. A flow circuit for oily water with a maximum capacity of 5 m3/h was available for the experiments. We limit ourselves to the discussion of two typical experiments: one on the measurement of the velocity profile inside a corrugated channel and one on the experimental determination of a critical oil-droplet diameter. Fig. 1 gives a sketch of a corrugated separator channel with dimensions: length 1.50 m, width 0.50 m, height 0.020 m. At a wave-peak (A) and at a wave-trough (B) the velocity profile was measured along a vertical line, with a TNO-Delft laser-doppler anemometer.

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clinical interventions would likely improve peri-operative outcomes. Aim of the study was to identify and quantify morbidity and mortality associated with VC surgeries. These data would be taken forward, after implementation of the care bundle, as baseline for comparison as to the efficacy of the intervention. Literatures and guidelines review will be undertaken to assist with the construction of the care bundle. Methodology Patients who underwent curative surgery for VC from 2017-2018 at Belfast City Hospital were selected. Patients were followed up for 3 years postoperatively Results 43patients underwent major VC surgery. Data were available for27 patients. Average age was67.2 years. Mean body mass index28.2 kg/m2. All patients had squamous cell carcinoma except one with melanoma. All were stage 1a-II. All patients received pre-operative prophylactic antibiotics. 37% received post-operative antibiotics for3-15 day. All vulvar wounds were closed using2.0 vicryland3.0 monocryl except one patient had clips. Groin wounds were closed using clips in 50% of the cases. Sentinel lymph node was used in25.9%. Regarding drains;62.4% had drain which were removed within7 days. Urinary catheter was removed within7.3 days. Laxatives were used in29.6% postoperatively. Mean hospital stay was12.1 days. Rate of readmission 14.8%, wound dehiscence11.1%, hematoma3.7%, infected lymphocyte11.1% and cellulitis22.2%. VC recurrence was 11.1% and death within the follow-up period was 22.2%. None related to surgery. Conclusion Major VC surgeries are associated with high morbidity. Variety of strategies employed by clinicians regarding antibiotic therapy, wound closure, drains, urinary catheter and laxatives. Evidence-based, team agreed selection of uniform interventions as 'care bundle' would potentially lead to standardization of care and improvement in morbidity. We will present summary of evidence pertaining to creation of such a bundle and present our initial prospective results following its implementation.