Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  • Users: JohnWeal
  • Content: Threads
  • Order by date
  1. JohnWeal

    Generator day tank elevation

    Good morning, What is the recommendation for the elevation of a day tank? We have a 3500 litre tank for each 2MW generator (5 in total) and feed is from 2 x 60,000 litre bulk diesel oil storage tanks. The bulk storage tanks are 80 metres away and approx 5m in elevation below the generator...
  2. JohnWeal

    100% RH through fans

    We have 4 fans vertically mounted pulling air from a plenum and delivering into a plant room throu louvres. Flow rate is 60,000m3/h per fan with only 3 fans running at any one time. Each the fans are long cased axial type with internal motor. The manufacturer states that the maximum RH for the...
  3. JohnWeal

    Exhaust Gas Heat Exchanger installation

    Good evening, An EGHEis to be installed in a power plant The total mass is 2000 kg. It is currently shown installed on directly into the building slab base floor. I stated that it should be installed on a plinth. (Or two plinths to be more precise - one under each of the two flat bottomed...
  4. JohnWeal

    Heating Sludge hot water circuits

    We have 2 sludge digesters on a Wastewater Treatment Plant each requiring 250kW in summer and 1050kW in winter to keep the sludge at 38 deg C. Heat energy is provided by 3 x CHP engines which have individual Pumps that take hot water from the main circuit. However, when a CHP out for...
  5. JohnWeal

    Screened sewage rising main

    Hello all, We have the following defined flows for sewage screened to 6mm (perforated plate) Daily average flows: 7000 m3/h Peak hourly to full treatment: 19,000 m3/h Minimum: 2100 m3/h The min / max velocities allowable by the client are 0.75 and 1.8 m/s respectively. Based on the max flow...
  6. JohnWeal

    overall heat transfer coefficient

    Hello For a stainless steel tube, 168mm OD and 2mm wall, carrying digested sludge at 36 deg C and the outer annulus carrying teated water at 70 deg C Counter-current flow and both flows are turbulant, is there a 'rule of thumb' practical overall heat transfer 'U' value used in calculations? I...
  7. JohnWeal

    Diverter or mixing valve

    Good evening We have a requirement to put water at 70 deg C into the annulus of a concentric tube in tube heat exchanger (construction is 2 streams of 7 tubes which are each 6m long) This is to heat digester sludge from 36 to 39 deg C. The calculated mass flow rate is 24 kg/s for the maximum...
  8. JohnWeal

    Standby boilers

    Hello All, We have 3 CHP engines that will provide heat energy to the hot water distribution circuit. As a backup energy input, we have to install 2 hot water Boilers (duty / standby operation when called to run) The boilers are each 2300 kW with burners that run on biogas and light fuel oil...
  9. JohnWeal

    100% saturated biogas pipeline velocity

    Hello, We have a centrifugal blower which is to raise the incline gas pressure from 17 mbar to 120 mbar for putting into a boiler. There is no process unit for removing moisture. (The client is taking all risks should this affect the burner/boiler or any other components) We do have condensate...
  10. JohnWeal

    Digester foaming

    Good Afternoon, The client specifications require the biogas offtake to be a minimum of 1.5m above the sludge liquor level. Has anyone on this forum experienced foam entering the offtake pipeline and if so, what are the consequences and remedial actions required? The offtake pipework is DN200...
  11. JohnWeal

    Biogas SIL rated Valve

    Good Afternoon, On a biogas pipeline where the biogas is saturated, is it acceptable to place the SIL rated slam shut valve before a condensate knock-out pot? Can the corrosive nature of the condensate cause the valve to malfunction? CH4 = 60%, CO2 = 37%, H2S = 400 ppm Pressure in pipeline is...
  12. JohnWeal

    Biogas velocity

    Good Evening All, Is there a recommendation in any standards for the velocity range for biogas in stainless Steel pipelines? If the moisture created during cooling is flowing in the same direction as the gas, the pipeline is laid with a 1 degree fall. If the condensate is draining back against...
  13. JohnWeal

    Anaerobic Digester Stainless Steel roof access

    Good afternoon We are having many questions asked by the client regarding digester roof access. The roof is stainless steel 316L and has 4mm sheets bolted from the underside of the radial roof beams. Therefore any components exposed to the gas are SS 316L. As the roof beams are not in contact...
  14. JohnWeal

    Carbon steel S275

    Good morning, We are specifying a fuel oil tank which is approx 7m long, 3m wide and 3m high. The tank will be located where the temperature is from minus 20 to plus 40 deg C. Due to the temperature, the actual grade of carbon steel i don’t think should be S275JR but instead S275J0. I would...
  15. JohnWeal

    Anaerobic Digester heat input

    Good morning, I am looking at sizing a heat exchanger for the heating requirements for an anaerobic Digester. The digester is a concrete tank with steel roof and is thermally insulated so that heat loss is limited to 1 degree C per day. The set point temperature is 36 deg C. The inside wall...
  16. JohnWeal

    Wastewater anaerobic digester design

    Good evening, We are currently designing two concrete digesters. Unfortunately due to height planning constraints, we have a design that has a height which is approx half the diameter. Diameter is 25m and height is 14m The decision has been made to only have a 3 degrees angle of the conical...
  17. JohnWeal

    Wastewater Grit Pumping

    Good Morning, We have a requirement to pump out grit from a sump which is 4.5m deep. The water level is controlled with a bottom water level of 0.6m and a top water level of 1.6m. There are two pumps in the wetwell which operate on a duty / standby basis. Adjacent to the wetwell is a 1m deep...
  18. JohnWeal

    Raw sewage pipeline materiL

    Good afternoon, Generally we use for most raw sewage buried pipelines ductile iron cement lined. A recent proposal has suggested glass reinforced epoxy. Has anyone had any experience they can share? Is it suitable for H2S, gritty wastewater, sludges and also perhaps vacuum conditions, thrust...
  19. JohnWeal

    Pumping downhill with a high point

    We have a 5km pipeline that is transferring sewage from an elevation 15m above the discharge. The pumping station is a sewer network pumping station with coarse screens. The discharge is the inlet screen chamber at the treatment plant. The reason we cannot gravity flow to the inlet works is that...
  20. JohnWeal

    Pumping municipal wastewater sludges

    Hi, Are there any simplified calculations for pumping wastewater sludges? We will be using progressive cavity pumps. I hear hat the once used TR185 is no longer reliable/accurate. Grateful if anyone can point me in the right direction.

Part and Inventory Search