(a)
Interpretation:
The rate (SCF/h) at which the biogas produced in the digester should be calculated along with the total heating value (Btu/h) of the gas.
Concept introduction:
The total solid obtained is the product of amount of water that is converted to solid under water treatment process and the solid of the feed digester can be calculated as follows:
The total heating value is obtained as:
Total heating value for gas = Fuel flow rate × LHV
Where, LHV is lower heating value.
(b)
Interpretation:
The rate of heat transfer (Btu/h) between the hot water and the sludge should be calculated along with the volumetric flow rate (ft3/h) of the water passing through the heat exchanger.
Concept introduction:
The heat transfer between hot medium and the sludge is calculated as:
Here, h is the heat transfer coefficient and A is the sludge surface area while Tmedium and Tsludge are the temperature of hot water medium and the sludge respectively.
(c)
Interpretation:
The fraction of the digester gas that must be burned to heat the water from 160? to 180? should be obtained and it should be commented that what will happens to the other 20% of the heating value.
Concept introduction:
The biogas is burned in 80% efficient boiler, there is some amount of moisture content present in gas, so that some amount of heat is used to remove these moisture content.
The mass flow rate will be calculated from this formula:
Where m is the mass flow rate, Q is heat flow rate a, Cp is heat capacity and dT is change in temperature.
(d)
Interpretation:
If there is excess digester gas available after meeting the process-water heating demand, then the potential uses should be explained.
Concept introduction:
The boiler furnaces have the heavy application of digester gases which are consumed to heat the furnace. But, when the water-heating demand is filled, there remains the gases and energy consumed in heating the boiler and these sources of energy can be consumed in various other purposes.
Trending nowThis is a popular solution!
Chapter 9 Solutions
ELEM.PRINCIPLES OF CHEMICAL PROCESSES
- and the viscosity of the water is 1.24 × 104 Nsm 2. Answer: Slug flow 1. Determine the range of mean density of a mixture of air in a 50:50 oil-water liquid phase across a range of gas void fractions. The den- sity of oil is 900 kgm³, water is 1000 kgm³, and gas is 10 kgm³.arrow_forwardA chemical reaction takes place in a container of cross-sectional area 50.0 cm2. As a result of the reaction, a piston is pushed out through 15 cm against an external pressure of 121 kPa. Calculate the work done (in J) by the system.arrow_forwardExample 7.2 Steam is generated in a high pressure boiler containing tubes 2.5 m long and 12.5 mm internal diameter. The wall roughness is 0.005 mm. Water enters the tubes at a pressure of 55.05 bar and a temperature of 270°C, and the water flow rate through each tube is 500 kg/h. Each tube is heated uniformly at a rate of 50 kW. Calle (a) Estimate the pressure drop across each tube (neglecting end effects) using (i) the homogeneous flow model and (ii) the Martinelli-Nelson correlation. (b) How should the calculation be modified if the inlet temperature were 230°C at the same pressure?arrow_forward
- Please solve this question by simulation in aspen hysysarrow_forward(11.35. For a binary gas mixture described by Eqs. (3.37) and (11.58), prove that: 4812 Pу132 ✓ GE = 812 Py1 y2. ✓ SE dT HE-12 T L = = (812 - 7 1/8/123) d² 812 Pylyz C=-T Pylyz dT dT² See also Eq. (11.84), and note that 812 = 2B12 B11 - B22. perimental values of HE for binary liquid mixtures ofarrow_forwardplease provide me the solution with more details. because the previous solution is not cleararrow_forward
- Introduction to Chemical Engineering Thermodynami...Chemical EngineeringISBN:9781259696527Author:J.M. Smith Termodinamica en ingenieria quimica, Hendrick C Van Ness, Michael Abbott, Mark SwihartPublisher:McGraw-Hill EducationElementary Principles of Chemical Processes, Bind...Chemical EngineeringISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEYElements of Chemical Reaction Engineering (5th Ed...Chemical EngineeringISBN:9780133887518Author:H. Scott FoglerPublisher:Prentice Hall
- Industrial Plastics: Theory and ApplicationsChemical EngineeringISBN:9781285061238Author:Lokensgard, ErikPublisher:Delmar Cengage LearningUnit Operations of Chemical EngineeringChemical EngineeringISBN:9780072848236Author:Warren McCabe, Julian C. Smith, Peter HarriottPublisher:McGraw-Hill Companies, The