The Philippine Toxic and Hazardous Wastes Act places limits on the quantities of toxic substances that may be discharged into the sewerage system. Guidelines on hexavalent chromium (Cr6+) limits the discharge amount to just 0.50 mg/L. If an industry dumps hexavalent chromium in the form of potassium dichromate (K2Cr2O7), what is the maximum allowable concentration of hexavalent chromium in % by volume and moles per liter of sewage water? Molar Mass: Cr=52, K=39.1, O=16

The Philippine Toxic and Hazardous Wastes Act places limits on the quantities of toxic substances that may be discharged into the sewerage system. Guidelines on hexavalent chromium (Cr6+) limits the discharge amount to just 0.50 mg/L. If an industry dumps hexavalent chromium in the form of potassium dichromate (K2Cr2O7), what is the maximum allowable concentration of hexavalent chromium in % by volume and moles per liter of sewage water? Molar Mass: Cr=52, K=39.1, O=16

Solid Waste Engineering

3rd Edition

ISBN:9781305635203

Author:Worrell, William A.

Publisher:Worrell, William A.

Chapter8: Landfills

Section: Chapter Questions

Problem 8.5P

See similar textbooks

Similar questions

Your organization has been hired to provide a water treatment process or device toremove toxic Chromium 6 [Cr(VI)] from water emanating from an underground source.Your organization has developed a treatment process that removes most of the Cr(VI)from the water to a residual concentration of 0.05 mg/L which is an acceptable level inline with the World Health Organisation. The underground water flows at 40 m3/h andhas Cr(VI) concentration of 100mg/L. The effluent flow rate is 97% of the influent flowrate, and the remainder of the water is discharged as wastewater. Calculate theconcentration of Cr(VI) in wastewater.
An industrial waste with a flowrate of 110 L/min contains 40 mg/L of zinc. Calculate: 1.) the pH required to maintain a zinc concentration of 2.6 mg/L (EPA's industrial limit for discharge into a sanitary sewer), and 2.) the dose of hydrated lime (Ca(OH)2) required (g/min).
Problem 6. A new manufacturing facility is being located in your town. It plans to produce 2,000 m³/day of a wastewater that consists primarily of water and the chemical phenol dissolved in it at a concentration of 5 mg/L. Phenol has a chemical formula of C,H5OH. The company has asked the municipal wastewater treatment to consider treating this industrial waste. Your plant currently treats 30,000 m³/day with an average influent of 350 mg COD/L. a) Estimate the increase in COD loading (kg COD/day) if you accept the industrial waste discharge? b) Estimate the additional amount of oxygen (in kg O2/day) needed to oxidize the phenol at the treatment plant.
A light manufacturing facility produces 125,000 gallons per week of sanitary sewage and uncontaminated wash water which are discharged to a municipal sewer system. A small parts rinsing operation flushes about 12 ounces per week of trichloroethylene down the sink. Does the facility have to manage their wastewater as hazardous waste (see 40 CFR 261.3)?
The air pollution control equipment on a municipal waste incinerator includes a fabric filter particle collector (known as a baghouse). The baghouse contains 424 cloth bags arranged in parallel, that is 1/424 of the flow goes through each bag. The gas flow rate into and out of the baghouse is 47 m3/s, and the concentration of particles entering the baghouse is 15 g/m3. In normal operation, the baghouse particulate discharge meets the regulatory limit of 24 mg/m3. when all 424 bags are in place and the emissions comply with the regulatory requirements: a) Calculate the fraction of particulate matter removed. b) Calculate the efficiency of particulate removal.
5. Chlorination, ozonation, and UV radiation are three commonly used disinfection methods for wastewater treatment. Answer the following questions: a) List 1 advantage and 1 disadvantage for each method. b) Why CT is termed as “dose" in chlorination? Using equation to link the inactivation number to CT. c) Which method is preferred for wastewater disinfection and why?
3. A hard drive manufacturer uses Nickel to plate its disks and then polishes them, resulting in a concentration of 50 mg/l in their 50,000 gallons per day wastewater stream. Their industrial permit standard for Ni discharge into the sewer system and treatment plant is limited to 0.2 Ibs./day. What percentage of the mass of Nickel must the onsite treatment system remove to be in compliance with the discharge standard? Use the following formula to determine the daily Nickel loading of the manufacturing system: Loading (Ibs/day) = Conversion Factor (8. Flow(MGD)
The ABC Citizens Waste Water Treatment Plant uses ferric chloride. a) What is it used to remove from the wastewater?b) In which process is the ferric chloride added?
A metal plating industry produces effluent containing Cu2+, Fe2+, and Ni2+ at concentrations of 25, 25, and 35 mg/L, respectively. The wastewater flow rate averages 290 m3/d. An ion exchanger with a capacity of 3 meq/g is used to remove these metals before discharge of the waste to the sewer. The exchange capacity of the resin on a volumetric basis is 2.0 meq/L. What is the volume of the ion exchanger and the mass of resin in it to remove these ions if the resin is to be regenerated once per week?
Liquid alum is used as a coagulant and specific gravity of alum is 1.33. One gallon of alum weights 6.05 kg and contains 3.22 kg of dry alum. Determine;(a)The alumconcentration (b)What is the volume of liquid alum required in order to prepare a solution containing 20,000 mg/l of alum concentration with final volume of 100 mL? (c)The dosage concentration of 1 mL of stock solution in a 2000 mL Gator jarsample.
As the consultant for designing STP, you proposed to use a completely-mix activated sludge system to treat sewage from a population of 45,000 PE. The sewage enters a primary clarifier with a BOD of 300 mg/L and SS of 360 mg/L. The primary clarifier removes 30% BOD and 60% SS. The aeration tank maintains a biomass concentration of about 3400 mg/L with a food to biomass ratio of 0.3 kg BOD5 per kg MLSS per day. The effluent BOD from the aeration tank is 16 mg/L. From a pilot plant study, the Y and kd values are 0.5 kg/kg and 0.06 per day respectively. Assume theunderflow concentration from the secondary clarifier of 9700 mg/L. Based on the above information, determine: i. The concentration of BOD and SS in the effluent of the primary clarifier ii. The volume of aeration iii. The mean cell residence time (MCRT). iv. The daily amount of biomass to be wasted.
A local plant has a pancake type disinfection tank. Diameter is 15 m and height is 6 m. Flow of filtered water is 43 m3/min. To meet EPA regulation, plant should achieve 3 log inactivation of Giardia Cyst at pH 8 and 20 degree Celsius. Currently plant uses chlorine as primary disinfectant. (*Answers in whole number, No unit) Contact time? min CT value? mg-min/L Disinfectant concentration? mg/L